1. Engine placement, some thoughts are well explained here:
http://www.liveantares.com/7Questions.htm#propulsion however one that remains is what about fumes, engine odors and noise from midship placement?

TC:

When ex-marine mechanics wax nostalgic, their reveries are of the walk-in engine rooms they could amble around in, patting the warm flanks of heavy horsepower. Competing nightmares of contortion and claustrophobia return them to the reality of small boat engine installations. If by chance one of these lads finds himself responsible for new designs, altruism may lead him to favour the next generation of marine mechanics with something closer to the former rather than latter experience.  I suppose I was predisposed to put the engines where I could get at them.

The compartments ahead of the engines were intentionally kept open to provide a place to stand, almost walk-in engine rooms.

These days, engine placement seems to be subject to of a number of priorities related more to marketing and inexpensive installation than to practicality. In the case of the Antares 44, the goal of creating an ocean cruising vessel for individual owners trumped any compromises (ed. there is that word again) related to charter vessel sales. This required that propulsion efficiency, accessibility and robust installation were the watchwords, hence the most practical engine installation we could work out.  We also wanted the props in the most effective location; low down and ahead of the rudders, with shaft exit at the keel/fairbody juncture and minimal shaft angle.

Though the possibility of fumes and odours should not be discounted, the modern diesel engines we deal with are not prone to leaks of any sort.  The presumption is that the engine spaces in small boats will be contiguous with the accommodations regardless of the boat style and manufacturers construct accordingly, there is zero tolerance for fuel, exhaust or crankcase fume leakage.  This was not historically the case and some older diesels were famously dirty.  Fuel line fittings could be subject to seepage and the standards and technologies associated with the ancillary equipment were variable.  These days if your engine’s presence is revealed by an odour, there is something that needs your attention.  The nice thing about the central engine placement; you actually know if something is wrong (sniff?) and can get at it to remedy the situation.

Any time the engine is running, it is ingesting a substantial amount of air which makes the engine space a mildly negative pressure zone.  Even with adequate intake ventilation this will always be the case.  As a result, some small amount of air is always drawn into the engine spaces from the accommodations; fumes or heated air thus being burned and sent out the exhaust pipe along with any drifting cat hair etc.  The Antares 44 is equipped with oversized exhaust blowers in the engine space ventilation ducts that may be turned on when the engines are stopped. The heat of the engines will thus be dissipated without warming the accommodations.  Any odours associated with the engine or bilges are also exhausted while fresh air is drawn in, again partly from the accommodations.

Noise will be unavoidable regardless of where the engines are located.  The perception is subjective but less is always appreciated so acoustic insulation is always in order.  If serious attention is given to that installation, it is quite effective as evidenced by modern gen set enclosures.  The central engine location with shaft drive and its associated propeller noise will theoretically be inherently more acoustically problematic than tail mounted saildrives for example, but the speculative lower sound levels do not justify the associated disadvantages in our estimation.

2. Piracy, and this goes for most catamaran designs, one common form of piracy (maybe more burglary) is boarding ships (common on monhulls through their dingy), not really an issue here but… As nice as the swimming stairs are, it does kind of seem as putting the red carpet out.

TC

Designing for the unlikely contingency of piracy at the sacrifice of ready and safe daily access to the water and docks would be tantamount to shooting yourself in the foot (both feet for a catamaran) so that someone couldn’t steal your shoes.

Maybe a grander answer to piracy is to address the social/geographic motivations for the undertaking rather than initiate a new class of porcupine cruising yachts. If this is too liberal an answer, you could try sprinkling carpet tacks over the deck at night to discourage the native population from setting their un-shod and unwelcome feeties on board, (idea stolen from Joshua Slocum). Just don’t forget to sweep them up before rushing on deck in response to the anchor drag alarm.

Joshua Slocum

3. On the topic of burglary, when I leave my home I lock my house down. Most designs seem to have a complete trust in humankind and just leave everything wide open. What about leaving my ship (house) for a 3 weeks hike? Does it come down to asking others to babysit it?

TC

The boater’s pride may be served by an enhanced demonstration that he is one of the ‘haves’, but presumably he must then accept some ancillary attention from the ‘have-nots’?

I believe for many years the general boat building practice has been to provide deck hatches and doors with the means to prevent outside access. Those who choose to leave everything wide open are perhaps satisfying their own sensibilities. In any case, most marinas deploy some kind of defensive perimeter against the unwashed masses, the gated community is thus made ubiquitous.

Friendly Mauritius Marina - Ambiguously directed measures may give one the sense of having already been caught embezzling?

I concede that I may be an idealist and naïve, but I like to think that the purpose of travelling is to have some interaction with the local geography (human and physical). Displaying a notion of security that is overtly offensive doesn’t seem very constructive to that end.

Avoiding ostentatious displays offers some security

Some kind of local babysitting for your cream puff will most likely be available for the duration of your three week hike.

Locals extorting a "watch your yacht?" ad hoc security service

I think engaging with the local enterprising kids offering ‘protection’ may be rewarding, at least the disparity between the haves and have-nots could thus be somewhat alleviated after three weeks of payments.

Seriously though folks, here is some firsthand experience with related stuff;

4. Another question that begs after reading how harsh you can be on other designers is what do you admire in other designs, is there anything you would do different design wise now with the Antares 44 or do you already incorporate those lessons?

Rather than ‘harsh on other designers’ I would suggest that the criticism has been applied to resultant product, which is an amalgam of marketing, purchaser indiscretion, building practice, costs, etc., the results of which may be equally dismaying to the designated designer as they are to you or me.

The unfortunate truth is that you only learn from your mistakes. When something goes well, it is a non-issue; a miss being a miss. Mistakes however dismay and plague one at night, preventing sound sleep (reveries of walk-in engine rooms). I have made a disproportionate number of mistakes in various fields of endeavour, so I know whereof I speak.

Appreciating the mistakes more than the successes leads to a level of self-criticism that hopefully translates into more rigorous design work. The same level of criticism is unavoidable when looking at the work of others though this may appear as being ‘harsh’.

There seems to be a remarkable degree of reverence for dumbass design in all products, I don’t confine my disappointment to boats.

I guess there is a usable shower in the basement

I hope that by writing (possibly amusing) critiques I will generate a more critical eye in the prospective boat owner, regardless of what he acquires.

To the very limited extent that the design for a rationalized product may be considered an ‘artistic’ statement, intentionally emulating the efforts of others would be anathema. However, though sensitivity to line and form could possibly be a genetic disposition, the exposure to example is a certainty, and in this regard I may be fairly regarded as a copyist.

Surviving half of famous 19th century catamaran

Whatever is ‘good’ and ‘attractive’, though subjective, will hopefully be automatically manifest in whatever I come up with. Everything is built on what has come before.

The 44 design is over ten years old yet still enjoys an increasing level of acceptance. The rationale that went in to the design still stands. The peculiarly limited number and scope of the readily identifiable initial shortcomings were rectified a long time ago.  There are some non-critical things I would possibly do differently today, not because they are mistakes to be corrected but rather because the underlying parameters have perhaps shifted, (do you like black more than white? or vice versa?). The changes would very likely meet with rejection equal to their acceptance so the wisdom is suspect. There have been changes over the years but primarily with equipment and hardware. The owner of hull #1 wouldn’t lose his way in the dark on hull #41.

5. Basically relates to 4 but do you incorporate feedback such as the modifications made by the Seaman’s Elixer crew in new builds? The cockpit does seem to evolve.

Customisation by individual owners seldom translates into a generally accepted ‘improvement’.  I like the idea of ‘ownership’ however and think that you should experiment (fool around) with your boat if you enjoy that sort of thing. When something proves out, is widely accepted as attractive, and may be adopted by the builder without undue liability, it may well show up in the new boat specs.

The cockpit in fact has not changed in any significant way other than the additions to the helm seat arrangement and the quality of the upholstery.  The evolution has been primarily from the utilitarian and toward the comfortable.  This reflects the general perception of what is desirable in a boat that will also act as a home.

Most design feedback is subjective and frequently countered by a non-apparent engineering rationale or an opposing opinion; but marketing is the craft of responding successfully to feedback in general and I think Antares does that rather well.

6. With regards to the cockpit, for your next build did you consider creating a little curve in the instrument panel above the compass in order to be able to move the bottom left and right instruments below the compass. Sort of like how it is done in cars. This would make the already awesome looking helm station even more aesthetic.

The flat real estate at the 44’s helm station is more expensive than Monte Carlo’s at $47,500.00 sq./M!

Cheap

Valuable

The ever changing nature of the electrical and electronic equipment that occupies the helm real estate precludes any curvaceous landscaping.  The cockpit mouldings were designed back in 2000 to accommodate any likely advancement on the prevailing displays.  Almost immediately Raymarine, Furuno. Et.al. taxed the situation with new product (‘bigger and better’).  It was fortunate that we were able to shift the engine instruments and other pedestrian stuff up onto the (flat) bulkhead without much trouble.

FRP boats tend to be around for a long time and designing automotive type sculpted dashboards is very short sighted.  The powerboat market seems to accept this readily enough and that perhaps betrays some design criteria that’s shallower than we are obliged to consider.  The general sailboat market is severely limited in display mounting by the ubiquitous pedestal and contingent cockpit obstruction.

We were fortunate to have the means, provided by the nature of the boat, to take advantage of the developments in electronic navigation displays as they have come along.

I understand your idea of raising the compass into a ‘bubble’ on the deckhouse top edge but this is a structural zone of some substance and thickness (1”+).  In practical terms, such a change would entail a larger lump than you would expect and require a modification to the major deck mould.  That cost added to the cost of re-tooling the panel would seriously handicap any cost/benefit analysis.  Additionally, I have intentionally avoided any obstructions to the lines of visibility for the seated helmsman.  This consideration also precluded top mounting a compass in the same space envelope.

It is always tempting to perhaps cheat the helm console spaces with some fancy geometry, but I won’t do it.

We must continue to rely on the helmsperson to provide the curves.

TC

Is this really protecting the participants identity?

Some editing & paraphrasing has been done to protect the participants from accusations of being dumbass, pedantic and more boring than customary.

The pictures are added for the relief you will deserve if you are obsessed enough to read all this stuff.

Q: Stig

Has the following question been covered somewhere in the blog? I don’t recall, but it’s been a while since I read the first one.

Question: “Does running one engine whilst under sail really save fuel?” I suspect not, but maybe there are exceptional circumstances when it can. To me, the proposition “for” goes something like this:-

When motoring under sail, you can switch off one engine, and still maintain at least 75% of your boat speed.

I would imagine that running one engine would tend to turn the boat, so it would have to be balanced by turning the rudder (which slows the boat), or trimming the sails in such a way to counter the turn (which I suspect would produce a lower forward force from the sails). If only one engine is running, does it tend to burn more fuel than it would if the second engine was running?

Certainly the reduced speed when running one engine means a longer trip, which means more fuel will have to be burnt in that engine anyway. The only circumstance which gives me some pause for reflection, is in very light airs where the engine is helping to create apparent wind, and the windward hull engine is the one being run. But this is a tenuous proposition in itself, so not a robust cruising strategy, and certainly not legal in the racing arena.

Putting all this together, I suspect that “only running one engine to save fuel” is one of those layperson yachtie myths, but would appreciate your comment, or blog if you deem the issue worthy.

A: TC

Jeez Stig, I was reluctant to support a blog in the first place on the grounds that I didn’t want to generate a lot of backwash that I would have to try and answer rationally (tough).

Your subject seems like just the sort of thing to get any number of theorists going around and around in a spiral of acrimony. As long as we keep your topic to ourselves however, I should be safe, but you have to promise.  (owch, ed. you’re hurting my arm!)

I think your question, “Does running one engine whilst under sail really save fuel?” is accidentally kind of catawampus; you will save the most fuel by not running the engine at all.  Maybe we should re-phrase and ask two questions;

1) Can I motor along more fuel efficiently with the sails helping? 

2) If so, should I use one engine or two?

One of the factors pertaining to either question is, ‘When do you want to get to your destination?’  

In a non-planing (displacement hull) vessel you can always save fuel, regardless of how many engines you use to burn it, just by slowing down. In the displacement speed regime, power is used primarily to make waves, a smaller wake equates with less power consumption.

Dolphins in your wake take advantage of your squandered fuel to get to their destination.

When you slow down, it takes longer to get there so you have to run longer but the rate of consumption goes down to your advantage in terms of fuel/mile.  To discuss the relative merits of various sail +power combinations, I suppose it is therefore rigorous to think in terms of some consistent speed to be achieved by using the various combinations?

Let’s try addressing the question 2  first;

The concept of running only one engine when two are an option is not confined to sailboats; I had to address it for the power cat fleet we built as well.  The sails just add another dimension.

When full power/speed is not required, the hypothetical advantage of running one of two possible engines is that; engines are less efficient when run at less than full power.  Running one at closer to its full capacity is possibly more efficient than running two at partial power.  Also, the parasitic loads associated with turning the engines and shafts are halved.  It’s these efficiency factors that motivate the discussion normally, creating a theoretical advantage over throttling back two engines.

In practice, the theoretical advantage is severely tempered in a twin engine power vessel by the necessity of dragging the one dead set of running gear, and having to apply excessive rudder to hold a course.  But we may suppose your sailing cat could run peg leg more advantageously since the idle prop will feather and create minimal drag.

Sailing Cat!

Without some very accurate fuel consumption metering, (rather impractical on engines at this size) it would be impossible to confirm the actual fuel saving at any given circumstance.  To complicate things, the engines are propped to work the vessel up to speed together so a single engine trying to get the boat up to speed will be over-propped (like running in too high a gear with your car), but as long as you back down a few hundred rpm from the max rpm achieved on one engine, you won’t overload it.  The power level and its associated fuel consumption will vary according to the prevailing sea and wind conditions.

It looks reasonable to presume that you can indeed run measurably more efficiently on one engine rather than two in the low propulsion power demand conditions you reflected on in your question, but the degree of advantage will be unpredictable due to the many variables.   (Hey, less noise, that’s a given anyway.)

To address question 1 : (do I win anything?)

Introducing the sailing under power aspect makes for a whole new spoiler in the equation, hmm.

I like the augmentation of the apparent wind thing, and as long as the sails are not back-winded, they may be presumed to be contributing something, though perhaps in some conditions not enough to overcome their own drag.  An analogy could perhaps be made with the aircraft wing which contributes its lift while the engines create the necessary forward motion and resultant wind over the wing to provide the lift.

Catamaran plane motor sailing on one engine

You could never motor sail effectively in a dead calm as the apparent wind would always be dead on the nose but at some points of sail in the presence of wind at sufficient strengths you could expect to motor sail effectively.

 So, in simplistic terms;

• If you just want to get somewhere most fuel efficiently, you would sail.
• If you want to get there faster, the course is amenable, and you are willing to spend some fuel, use an engine and sail.
• If you want to get there even faster use two engines and sail?
• If the course is not amenable to sailing effectively, don’t use the sails.

I don’t really fathom the idea; “When motoring under sail, you can switch off one engine, and still maintain at least 75% of your boat speed.”  The ‘speed’ obtained will be the result of the total propulsive effort (sails + engines) overcoming the resistance and the real numbers are highly dependent on the boat, its engines, props, speed regime, wind speed, point of sail, etc.  Declaring a particular percentage seems to me to be rather bold.

Ted
P.S. There’s no way we are publishing this confusing stuff.

Q: Stig

The great thing about ignorance is; you don’t know what you don’t know, so you can proceed in blissful ignorance

I think I follow your explanations, so if I find myself so disposed, I will carefully start to experiment on this issue. If I learn anything useful from my experimentations I’ll let you know (but don’t hold your breath).

On a related issue, one last question (I promise).
My boat is fitted with a feathering prop rather than a folding prop model. I imagine the feathering props are more robust and responsive in fwd./aft evolutions, whereas the folding props are better with significantly reduced drag? Am I correct in my speculations? Could you put a figure on greater drag reduction of the folding prop? (is there a case for changing)

A: TC

Be not concerned, I never undervalue ignorance and cultivate a personal style in this regard, always “seeking my bliss” at every opportunity.

The Maxprops you have probably generate about the least prop drag you could achieve when they are feathered. The blade shape is compromised however in order to be “flat” and slice through the water when feathered.  Racers love them.  Also, they have killer reverse power in comparison with props that have blades maximized for forward thrust efficiency at the expense of reverse, (most other props).   This makes them well loved in the harbour.

3 Blade Maxprop

The folding props we are using now were developed by Volvo and, as the investment would have been substantial, I have to presume they examined all the options and came up with their best effort. These props fold into a kind of shriveled flower configuration that looks like a turbulence magnet, but apparently it isn’t so. They seem to work well, are serviced by Volvo’s worldwide network, and are much simpler mechanically.

Volvo Props

But, there is a more decisive reason to consider the option depending on the kind of boating you imagine yourself doing.  Unlike the flat blades of feathering props, the folding prop blades may be constructed with the curvaceous twisted blade surfaces that are critical for maximum efficiency under power.

Plan of Blade

The twist is necessary to make the blade surface conform to change in attack angles associated with the desired pitch at different points on the diameter is not possible with a flat blade.

The measurable power (fuel) efficiency advantage of a folder style blade may be more important to you than a minor increase in drag.

If you spend a lot of time motoring (or motor sailing) and have a fuel budget or range target, you may opt for a more efficient powering prop over a more efficient sailing prop.

Lately, fuel consciousness has been forefront in the minds of our new owners so we felt that the ‘standard’ prop offering would be the folder.  They are noticeably less effective in reverse than the feathering props however so if you are used to the Maxprops and are known to be a menace in the harbour, take your time, keep the fenders available, and cultivate the old manoeuvring skills.

There are a number of prop performance comparison exercises published on the web (eg. Segeln magazine 2008), but the science may be tough to apply to a particular boat and circumstance.   There is a surprising variety of designs on offer, arguments will abound, (No, I don’t want to know!).

I wouldn’t switch out the Maxprops unless they become worn out or damaged. They are still a preferred item from a pure sailing standpoint and have survived very well in the market, (I installed them on racing boats when they were a novelty, early 1980’s?), presumably for good reasons.

Q: Stig

Remember that discussion we had about the value of running one engine versus two, and I speculated that there might be a benefit in light airs going to windward in running one engine? Guess what, I’ve met a fellow sailor of a Nautitech 40, (which has the same engines as my Antares), who is convinced that running the leeward engine works. He has played around measuring fuel consumption, (he’s careful with money, and he’s German). He’s attached his fuel lines to bottles with volume marks on them.  

Anyway, the most surprising thing he discovered was that the fuel consumption of the engines at idle and 2,000rpm was the same. And this was measured over a 4hr run period. Even as I write this, I am questioning it, so I’ll have to interrogate him further on his methodology. But the implication is clear, there is a fuel overhead in running an engine, even if it’s not doing any useful work. So in the light air sailing to windward scenario, the engine would work to initially generate speed, but once the sails started to power up, the engine would be less pressed, and burn less fuel (ie, same revs, but less torque). Or something along this line of thought. The benefit would appear to only be in this narrow window of light air and low rev’s. He routinely will start the leeward engine when struggling to do 3kts, and claims significant speed improvement at 2,000rpm, with little apparent turning effect, so minimal additional drag from helm correction, and miserly fuel consumption. Certainly a lot less that if he was running the windward engine at the same time. Fuel for thought.

A: TC

There’s nothing wrong with the theory.  It’s all simply explained by relativity.

A.E. explains his unified motor sailing theory

The prop load will be reduced (along with the fuel consumption) by whatever contribution the sails make. At any time, the engine rpm will however have to be sufficient that the engine will contribute to the sailing speed or the prop will drag start to drag (heavily). Getting the same fuel consumption at idle would be expected if the engine speed isn’t high enough to give the prop some bite, it’s just going along for the ride.

As the vessel speeds up, the engine will have to speed up to contribute power, eventually reaching its governed max rpm and at some boat speed beyond, there will be no more contribution and the prop will drag from there on up as it will be spinning below the rpm required to produce thrust. (We’d be really cooking along by then!)

The prop pitch is the factor that prevails here; it is configured to match the engine’s maximum power capability to the prop load at a specific boat speed, such load being dependent on the relative velocity of the prop race. The pitch would have to be excessive for normal conditions if it were to be matched to possible high sail + engine vessel speeds.

This sounds more complicated than it is – an analogy; you can push a car up to running speed but not beyond, your contribution will become negative (feet dragging) once the engine starts and pulls it along faster than you can run. Your pushing contribution will diminish as the speed gets up to that point.  If your legs were longer, well…

Q: Stig

 20 knot motor sailing?  I’m up for it, as soon as you can spec me an adjustable pitch propeller that I can progressively wind up as the wind cranks,  unless you have a more cunning plan in mind?

A: TC

The variable pitch prop spec herein provided;

Huh, H.M.S. ‘Dwarf’? Maybe they built seven of them?

And…

Just one of several Cunning Plans available on the Internet

When you add in the issues of relative wind and points of sail, I think you need a bigger blackboard. It’s time for an empirical study.

Q: Stig

Today I had a light and variable sail to windward so I applied the single engine + sails methodology and I tried the one engine strategy.  I had my light bulb moment as soon as I tacked.

I have always assumed (the motherhood of most cockups) that you should run the leeward engine, (I guess a sailor’s natural instinct to favor anything that tends to help you get to windward); however I found that the windward engine balanced better.

What I believe is happening, is that as the wind drops and the engine starts to really make a difference, the apparent wind moves forward and the boat wants to round up. With the windward engine powered up however, the boat’s tendency is to turn away from the wind, which is exactly what is required. With this setup, I noticed that the autopilot did a lot less work as everything stayed in balance much better, which presumably would translate into faster and more efficient running.

At one point of sailing, with the windward engine at 1,600 rpm, I managed to sail faster than the true wind of 5knts. Normally when solely motoring we have both 29HP Yanmars at 2,000 – 2,400 rpm for 5 – 6.5 knts.

My conclusions on the subject are:-

1. Always use windward engine.
2. Effective true wind range is 3 – 10 knts – Obviously it works in higher wind and engine revs, but why burn the fuel when you don’t need to.
3. Effective true wind angle is 60 – 140 degrees – So it’s not a great tacking to windward strategy, more for a straight line track. Particularly in really light stuff, just motor straight to windward if that’s where you want to go.
4. Effective engine rpm range 1,500 – 1,800 – Match rpm to wind speed and angle. In light stuff it is easy to over rev, and be headed by the apparent wind. Above 1,800 rpm, the wind is usually strong enough to just sail.

A: TC

A very useful real world trial!

I think it is interesting to note that the engine rpm necessary to make a contribution is lower than what one might intuitively expect, (1,600 rpm motor sailing vs. 2,000 rpm when purely powering), to achieve 5 knots.

The prop pitch/rpm always has to create a theoretical tailrace speed greater than the boat speed in order to make thrust (and burn fuel).  The degree of speed difference will diminish as the vessel speed increases but apparently there is still sufficient surplus at 1,600rpm to contribute thrust while  at 5 knots.  Presumably the engine is working a lot harder when both engines are at 2,000rpm without the sails helping.

You have to love it when imaginings (theory) seems to play out in the real world.

Q: Stig

I spoke to my German friend again.

His engine test was 4hrs at idle, 4hrs at 2,000 rpm, but in neutral sitting in the harbor. Nothing to do with sailing as such! Still he claims identical fuel consumption. He can’t explain it, but would love to hear from someone who could.

A: TC

Love is in the air.  We can leave props and sails out of this one.

This apparent paradox of fuel consumption is related to a story I was told starring the great Rudolph Diesel himself as protagonist.  (Most certainly it is apocryphal since the invention of direct fuel injection post-dated him by about ten years.)

Nevertheless, here is the story;

A Riddle

The prototype diesel engine was banging away nicely with Rudy manually controlling a rack and pinion/plunger arrangement to precisely meter the amount of fuel delivered by a fuel injector for each combustion event. He thought it would be nice if he could let go of the rack at some low fuel rate position and let the engine idle on its own, so he devised an adjustable stop mechanism to hold it at an ‘idle’ point with the appropriate setting.

The engine was revved up and allowed to drop to idle speed at which point Rudy set his adjustment stop, correctly presuming that one perfect idle size drop of fuel would be consistently delivered per injection shot. He then revved up again and returned the rack against the stop, expecting the engine to slow back down to idle.

However, instead of slowing down it continued to speed up, took off and blew apart. Huh?

While he was in the hospital, Rudy gave the riddle some serious thought.

Isn’t this connecting rod supposed to be straight?

Rudy Considers the Riddle:

With a non-governor equipped gas engine, the throttle butterfly plate (#5 below) modulates the supply of a combustible fuel air mixture and at some throttle plate minimal position, the engine has to work to draw in whatever it gets to burn and it is starved of the means to run any faster (throttled).

It is still possible to over-rev the engine by holding the throttle plate open at no load but for many applications (like cars) you can sense the load and react accordingly, directly modulating the power output. Nicely, the arrangement will provide consistent idle speeds at a particular throttle plate position. Also, even if the throttle plate gets stuck in some unfortunate position, (too open for the applied load) and the engine over-revs, you can always cut off the electric spark ignition.  In any case with this arrangement, the operator directly controls the power output; the engine speed modulates according to the load.

The (modern) diesel engine has no throttle butterfly so it is free to ingest as much air as it wants, power being modulated purely by the injection of metered fuel. The ignition is initiated by the heat of compression so there is no need for spark ignition.

When Rudy set his idle stop he was presuming that the fuel injection rack would have the same function as the gas engine throttle stop, reasonably enough, but there is no restriction to the available air, and the rack controls only the fuel injected per combustion event.

This means that at 500 rpm idle, Rudy was injecting 500 drops of fuel per combustion even at a specific rack setting (lets presume his idle stop position) which equates to 500 drops/min at this speed. When he goosed the engine up to 1,000 rpm and quickly returned the rack to the previously established idle stop position, (500 drops/combustion event), he inadvertently continued to deliver 1,000 drops/min which corresponds to the engine rpm. So the engine had twice as much fuel as it did at the established idle speed, giving it no inclination to slow down in the absence of a corresponding power load. In fact his engine would have needed the rack set to virtually the ‘no fuel’ position in order to slow down. Eureka!

Rudy got out of intensive care and returned to the drawing board.

Rudy Fixes the Problem

No human could be expected to constantly stand by the fuel rack and modulate it by hand at idle and various loads so a self-governing arrangement would have to be used in the fuel injection system. Governors were common enough for steam engines and self-regulating gas engines so that was not too tough.

With the typical mechanical governor, you ask for a specific engine speed by tensioning a spring which fights against a set of centrifugal flyweights spinning in concert with the engine rpm. When the spring wins, the fuel rack moves towards the full fuel position, when the flyweights win, the fuel rack moves toward the no fuel position.

Confusing Yanmar Governor Diagram

For a specific spring tension (your direct input), the flyweights and spring come to an agreement, balancing the fuel injected to the power load. You have no direct control over the fuel rack position which could be anywhere at a specific rpm depending on the load.  But you do have control of the engine rpm within a prescribed range.

To prevent you from over-speeding the engine, there is a limit to how much spring tension you can apply, and to establish a fixed idle speed there is a minimum spring tension setting. The ultimate power possible is dictated by a maximum fuel rack setting which is calibrated to agree with the combustion air aspiration limits and physical capabilities of the engine.

Unlike the throttle control that modulates the power output directly, the manual control of a diesel requests the governor to run the engine at a particular rpm, and it modulates the power required to attain that speed.

This type of governing is used in all the small marine propulsion diesels which, due to their size, are not yet available with electronic fuel injection.  The more obvious on board example of diesel engine governor control is the gen set engine which always runs at 1800rpm to create 60Hz ac power, regardless of the applied load, the fuel rate automatically modulating appropriately.  Common gas engine governor applications we are all familiar with are typically lawn mowers and tractors with settable speed levers.

The mystery part that falls out on the floor when you take your lawn mower engine apart; the governor flyweight assembly.

So, back to the answer you would love to hear (any time now); your friend was really measuring his engine’s ‘rolling resistance’ more than anything. His governor was delivering only enough fuel to keep the engine spinning at various speeds and the fuel/min difference would be low in the absence of an rpm dependent load, like a propeller. His alternator electrical output may have been equally satisfied at idle or higher rpm depending on state of charge etc. Presumably, the aspiration loads (intake exhaust of combustion air) plus water and oil pumping loads would increase with higher rpm but the vagaries of the system efficiency may make them of little consequence.  Coasting is just that.

If he had had a gas engine, your friend would have observed the same apparent fuel consumption paradox but he would have only had to crack the throttle a very small amount to keep the engine to revved up under no load.  The action of moving the diesel throttle levers significantly forward would not have confused the issue.

Our intuition incorrectly associates the throttle lever motion directly with fuel consumption, our sensibilities being informed by the interaction with automotive (throttled) engines.

Your friend was just blowing a lot of hot air around, but like that other German fellow Rudolph Diesel, he will figure it out eventually.

Are you more or less confused now?

Stig:

Bloody marvelous, you never cease to amaze.  (ed. keep this in!)

Despite being on the edge of comprehension for most of the email, I believe I got it.

I’ll forward it to my German friend, although it may have to wait until a face-to-face meeting in a week or two, for me to badly explain it to him.

TC:

Well, that’s all she wrote, you made it to the end.  We wish ‘Stig’ every success in his motor sailing, and explaining.

Many Thanks to ‘Stig’ for generously revealing his mixed bag of thoughts, reasonings, and confusions; typical of those from which we all suffer but normally guard against sharing.  The subject matter is especially convoluted and we never would have gone there but for him.

There is no better way to straighten out your own thinking than trying to explain a rationale to someone else.  This quickly reveals the mushy spots in your own concepts.

Me; working out the relationships between motors, sails, props, governors, fuel.

The steering committee prepares to vote

The following discourse is actually about steering systems for your catamaran so you hopefully won’t need to travel in the economy classes.

This old print of a Fijian charter boat illustrates the ubiquitous vessel steering problem; how to see where you are going at the front end while steering from the ass end, (note this ship is moving away from us despite the pointy bits).

The two lads manning the 20’steering oar can’t see around the deckhouse, so a lad in the bows is calling directions which are being relayed back through the fellow on the coachroof.  A third lad at the steering station appears to be disputing whether to push or pull on the oar.  I can’t readily explain the point of sail or the tell-tales, but everyone looks quite jolly in any case and satisfied with the performance, two lads apparently fishing more coconut wine from the port hold.

To alleviate the typical steering /communication problems, there has always been some considerable incentive to engineer remote steering arrangements whereby the guy at the helm can actually see where he is going.  (The recent regression in this matter exhibited by some modern catamaran designs might possibly be attributed to some genetically transmitted ancestral nostalgia.)

The practice of using a tiller to steer with didn’t disappear with the 16^th century as suggested by the diagram above, though the whipstaff has become a relative rarity, at least in its boating connotation.

If your vessel is really too small for one anyway, you can just do away with the deckhouse.  You can then sit with a tiller in hand, see where you are going, and take what’s coming to you, (wind, spray, sleet etc.) It’s perhaps not as robust as it looks; despite the apparent simplicity there is a lot of stuff here to consider.  Each hinged joint in the tiller and rudder assembly is subject to potentially very high twist loading, you have to concede the space for the sweep of both tillers and the exposed tie bar, plus there is no apparent provision here for the times you may want to let go for a few minutes.  (The apparent disagreement between the rudder angles is a little hard to explain.)

Also in the above catamaran example, there is little apparent improvement in the above helmsman’s seating comfort over the yacht practice of 1500 years ago;

The protection and comfort of the helmsman make a major contribution to the safety of the vessel, another motivation for remote steering systems.

Ropes, Cables and Chains

Moving ahead to the 17^th century plus, we see the advent of rope and pulley systems and the birth of a new nautical decor theme, the ships wheel.

The helm of the rope system will look something like this, at least in principle…

or this.  The common sailboat pedestals now use chains and cables rather than ropes and pulleys, but they are still a hybrid of figure ‘H’ in the ‘Progress’ diagram above.

Figure ‘F’ illustrated in the diagram would have a lot of slop in it as it doesn’t take into account the arc of the tiller; when the ropes are snug amidships, they will slack off as the tiller traverses.  As will this more modern experiment…

You wouldn’t think of driving your car away from the curb without 100% steering confidence but boaters seem to be less fussy.  The bronze rudder, rudder port and tiller are up for the job, the tiller extension and cup hooks for the turning blocks are not.  There are no rudder stops.  Even a small boat can run over someone in the water, to say nothing of the embarrassment of pranging the dock.  Hopefully this installation was revisited before the sea trials.

To keep the ropes, cables or chains tight throughout the arc of tiller travel, you have to use a quadrant rather than a straight tiller to keep the geometry consistent.  These come in a variety of forms;

This otherwise Herculean installation does not appear to have a top bearing for the very long rudder stock.  As a result, the steering load and cable tension are imposed as bend stress in the stock and exaggerated side loading in the rudder port bearing.  Again no stops are in evidence.  The installation looks much more robust than it actually is; despite the use of a nice vintage sprocket quadrant.

The cable quadrant in this case is actually a complete ‘wheel’, the cables wrapping around aft.  This stock has a top bearing.  The two stubby things with rubber hose over them are the stops provided by the quadrant manufacturer.  It was left up to the builder to give them something to bear against, nothing is in evidence however.  Notice the weight of the rudder assembly is borne by the aluminum quadrant bearing on the bronze stuffing box which in turn is held up by the hose, all in a nice mildew farm/corrosion encouraging environment.  Steering gear never seems to get much respect, as long it sort of works, though its integrity is of prime concern to a cruising vessel owner.

Cable systems provide lots of concerns regarding installation, wear and maintenance.  Note the example in the upper left uses conduits to guide the cables rather than sheaves, permitting some artistic routing.  The owner of the hand with the cloth running along the cable is searching for ‘meat hooks’, broken cable strands that indicate imminent cable failure.  Have some Band-Aids handy.  It is interesting to note that the cable securing methods and general hardware quality commonly used for yacht steering gear would never be acceptable for even the vessel’s least critical standing or running rigging.  Maybe that’s because you can’t usually see the steering gear.

Chains and sprockets aren’t too bad for it, but cable and sheave arrangements have considerable frictional losses, especially with tight cables.  Flexible conduit cables rely on the integrity of the plastic liners to minimise friction, demanding the fewest possible wide radius bends.

The above diagrams are of monohull installations, designed to turn one rudder.  The simplest way to control a second remote rudder is by means of a tie bar between a tiller arm on the controlled rudder stock and a tiller arm on the ‘slave’ rudder stock.  In practice this can be rather tough to accommodate in a catamaran.  The ideal placement of the rudders fore and aft should dictate the position of the stocks and tiller arms. Practical limits on the vertical positioning will be dictated by the shape of the hull and bridge deck stern sections.  Expedient arrangements to fit a tie bar internally can compromise both the steering system and the shape of the vessel, so the

tie bar may sometimes be found outside, exiting one hull and entering the other.  This arrangement inevitably results in the exposure of the rest of the steering gear and the aft compartment to the full effects of the environment as the hull openings can never be made watertight.

Tie bars and end fittings can be easily acquired in marine grade materials and configurations but this may not always be done.

The assembly on the top is an automotive adaptation with a tapered pin mount, (potentially very hard to deal with without a cutting torch if the taper releases before the nut comes off, or the builder has neglected to correctly taper the hole in the tiller arm in the first place).   The industrial style on the bottom may be acquired in stainless steel and permits the use of a through bolt attachment (nice to have).

This one is a lightweight hardened anodized aluminum joint with a replaceable Delrin ball mount that insulates the components against galvanic corrosion.  Though possibly an aircraft technology derivative, it seems to be ideal for our kind of marine application.

The tiller arms and quadrants need to be of sound construction with solid connection to their rudder stocks. There are lots of manufactured castings in aluminum that do the job well with minimal weight but they are not always used.

Massey Ferguson sugar cane weeder

In the above example, the anorexic rudder stock has been reduced still more dramatically by grinding a square end on it.  The stock’s diameter and its other structural properties should rightly be subject to calculations that take into account the speed of the vessel, size of the rudder, rudder balance, bearing spacing and presence or not of a heel support bearing (open rudder or skeg arrangement).   This installation doesn’t look to me like it would measure up?  Even if the top of the stock doesn’t twist off, the tiller arrangement puts all of the steering force into one of the bolts.  Peculiarly the imaginative stainless steel welded fabrication would cost more than a real marine cast tiller arm, bit of a mystery here on several counts.  It is usually easier and cheaper to just do it right in the first place.

Hollow stocks have the advantage over solid ones by saving weight.  The extra material entailed by increasing the diameter is more than offset by the removal of the core material which has a minimal contribution to the torsional strength.

This example of a custom tiller arm rightly relies on clamping pressure to make its connection with the stock.  Locating keys or pins are always secondary to the transmission of the load and if these do come into play, the proper clamping force has failed.   It looks like this cat’s steering system design occurred rather late in the design process.  Though the stock, bearing and custom tiller arm look rather elegant, the motivator appears to be a push-pull cable system; incongruous and not so nice.

This is the same vessel’s push-pull cable anchor which is expected to take the full steering load, it certainly doesn’t look like any kind of a match for the stock and tiller capabilities.

In any case, the push-pull steering hardware is derived from the outboard motor and stern drive market which has different requirements for integrity than what we expect for an offshore cruising boat.

The only incentive in trying to adapt it to a cruising catamaran would be initial cost constraints.  It’s hard to see how that can be justified.

This is reportedly an installation in a 49’ cat.  There must have been no residual cash left over by the time someone remembered its steering system.  Do any of the cable components look like a sea going propositions?  I guess the little pin sticking up is a rudder stop.

Nutty Steering Gear prize goes to this cat with two helms connected via push-pull cable systems to track and car arrangement connected to rudder quadrants via cables and pulleys.  Wow, avoided installing a tie rod though…

Perhaps you are wondering why I keep mentioning rudder stops?

Peculiarly, the greatest loads on the rudder, stock and steering gear are experienced when going astern.

As long as you are going forward, the flow over a rudder with a stock positioned well toward its leading edge tries to push the rudder to the amidships position where it may trail with no significant load.  This makes for a kind of ‘fail safe’ condition.  When going astern however, the flow tries to twist the rudder around backward and the force may easily exceed the normal forces necessary to steer the vessel.  Strong rudder stops placed to limit the swing to about 35⁰ are necessary to prevent the reverse flow from damaging the rudders and steering gear by forcing them beyond their physical limits.  Even if the steering gear was free to swing 360⁰, surprisingly strong and rapid rudder pressure when going astern can easily overwhelm the helmsman and even cause injury, to say nothing of the loss of vessel control.  Rudder stops designed to take the load will at least limit the forces to be dealt with.

In the absence of rudder stops a cable/chain steering system may reach its mechanical limits by crunching a chain-to-cable splice into a helm sprocket for example.  This kind of repetitive mishap will soon do damage to the components.

Hydraulic Steering Systems

Hydraulic systems have offered a ‘new’ alternative for connections between the helm and the rudder.  This is a sheet stolen from Kobelt Manufacturing that explains the principles;

You may easily add additional helm pumps for multiple steering stations and an autopilot pump to the circuit.  They are very versatile.

Hydraulic steering systems can easily have great power and integrity and readily scale up for large size installations,

but in the pleasure boat scale of things, the components and piping deal with very low flow rates and high sensitivity.  This means that the quality of the components must be very good despite the small size and cost limitations of a competitive market.

This example is in a 49’ aluminum vessel installation using stainless fittings and hose connections.  The bypass valve permits emergency steering by tiller.  The cast bronze ram construction is certainly not the weakest link, but it is bolted to aluminum with no insulators apparent.  Mixing copper based alloys with aluminum is not at all good for galvanic corrosion and should be kept in mind when selecting fittings and installation methods.

This is a 53’ cat installation using industrial plated steel hose connection fittings and an aluminum bodied ram.  The ball end fitting looks particularly unhappy, the hoses and fittings are past their best before date.  (Sometimes a picture itself seems to smell of mildew and bad bilge water.)  Industrial hydraulic hoses commonly have fine braided steel reinforcement under the rubber cover to hold the required pressure.  Exposure at the end fittings or perforations of the cover can rust away that reinforcement wire, something else to watch for in the marine environment.

For a sailboat, hydraulic steering has one drawback that needs to be recognized.  With the exception of a few oddballs;

all of the current boat helm pumps are rotary in design and displace a determined volume of fluid per turn either direction, which is a critical match to the ram used in order to establish the desired mechanical advantage (turns lock to lock).

This particular model has adjustable displacement for more or less turns/mechanical advantage.

There is always some leakage by the pumping elements.  This leakage is very low by industrial standards but so is the flow in the boat system and inevitably there can be no such thing as a ‘master spoke’ in the helm wheel.  The wheel will gradually creep under load as you are steering against some rudder pressure.  This means you need to rely on a rudder angle indicator rather than a master spoke to tell you the rudder position.   The small rod in the rust installation shown above will be there to operate an electronic sender unit for an indicator or autopilot feedback.

In a catamaran installation it is possible to connect a separate ram to each tiller and eliminate the tie bar, which may solve an awkward installation situation.   This requires that the two rams be connected in series, the oil from one discharging into the other, rather than parallel, both receiving fluid directly from the helm pump.  This arrangement compels the two rams to move synchronously, keeping the two rudder angles in agreement.  The minor leakage past the ram seals will gradually allow the alignment to wander a little so a valve is provided to make corrections every so often.

The bane of all hydraulic steering systems is the entrainment of air pockets in places where you would expect fluid.  The air is compressible whereas the fluid is not.  This makes for spongy response and skips or outright ineffectual pump action.   To get the air out of the system it is necessary to vent it out at a few spots where it would otherwise be trapped.  Rather than circulate, steering fluid just moves back and forth so ‘bleed’ fittings are usually required at the ram ends.  Series ram arrangements as shown in the above diagram may be particularly tricky to fill and bleed.

Long tube runs with small internal diameter and restrictive fittings add up to a lot of frictional losses in hydraulic systems, especially when quick response is called for and flow rates peak.  The drag may be quite noticeable when spinning the wheel over.

Every extra fitting is a potential leak point.  The piping is unsecured and subject to mechanical damage.  Regardless of what a manufacturer may advise, in practice copper tubing will immediately turn green and fuzzy in a salt environment and have a very short lifespan.  The brass fittings are apparently screwed into the aluminum valve blocks, electrolysis will shortly turn the aluminum to white powder.  With the widespread availability of direct drive electric motor/pump equipment, many having integrated valve bodies, why would you use such a hokey belt driven arrangement?  (It does look pretty when new.)  There are several manufacturers of complete engineered systems with competitive pricing.

If a hydraulic steering system is well engineered and installed, free of air entrainment and leaks, it will work indefinitely and it offers a good deal of versatility and scant wear of the components.

The Autopilot

For cruising boats an autopilot has become an essential option.  The autopilot cares not for your wheel and is best installed as close to the business end of the steering gear as practical.  This may allow it to remain effective even if there is some disability in the mechanical connections to the wheel, thereby making it a possible emergency steering option.

These after the fact arrangements or under-pedestal chain and sprocket drive motors rely on the cable and pulley system to transmit the steering effort.  The ‘dumb’ autopilot can apply taxing forces to the steering gear that you would not sensibly do if you had the wheel yourself, you may soon discover the weakest link.    (Do you think this guy’s wheel nut is actually only on by one thread?)

Autopilot motors are often installed as a structural afterthought though their power capacity generally exceeds that of a manual helmsman.  The anchoring and connections need to be at least as strong as any other component of the steering gear.  This example uses a chain and sprocket on a common shaft with the manual helm.  The motor power is transmitted through the chains, turnbuckles, cables, sheaves and quadrant entirely in common with the manual steering gear.

Autopilot actuators are commonly available for direct attachment to a tiller arm.  I think that is a better option if you can swing it.  In this way, the power transmission doesn’t rely on the integrity of all the helm related hardware.

This example is a self-contained hydraulic unit with integrated ram, pump and motor.  It looks like the mount bracket is pretty solid and the installation is neat and serviceable.  The tiller and rod ball end look to have suffered some corrosion.

This example of a hydraulic autopilot actuator and its pump has an electronic rudder position feedback unit apparently attached with hose clamps.  You have to imagine that you may be reliant on this kind of stuff in the middle of the ocean, in bad seas, at night, and select your gear accordingly.  It doesn’t have to be large, clumsy or heavy to work well.

Hydraulic rams will have some resistance even with the valves set to bypass fluid directly from one end to the other.  This means that some manual steering resistance or damping will be felt.  To alleviate the general tendency of hydraulic steering systems to drag, very thin hydraulic fluids in common with aircraft control systems are generally used rather than the heavier industrial oils.

I like to see engineering ‘elegance’ in the steering equipment and its installation, (minimal exposed junk and connections).   If you are going to use electrical power anyway, the hydraulic actuator seems like a roundabout way of doing things.  Developments with straight electric linear actuators with increased power and clutch features makes the look pretty attractive.

These are two examples of electric direct drive actuators.  The one on the top is rotary in nature and requires a drag link to connect it to a tiller arm, the black thing being an electronic follow up unit.  The one on the bottom is configured to drive a tiller arm directly.

This is another electric linear actuator (above) that comes with a neat video of the guts in motion -http://www.youtube.com/watch?v=mYN3IQdaV_Q&feature=player_embedded

Shaft and Gear Steering System

By now you are wondering what happened to the direct geared steering system illustrated in figure ‘G’ of the Progress diagram way back at the beginning.  I thought it should be a case of the best saved for the last.

Up until about the middle of the 20^th century, geared systems were the norm, even for small boats, but the systems fell out of general use as they were heavy and had practical installation limitations.  Developments in CAD CAM manufacturing efficiencies and the realization that both cable and hydraulic systems were perhaps rather precious for certain applications rejuvenated the idea that you could configure a shaft and gear system that would be affordable and of acceptable weight and versatility.  Though not apparently cost competitive at initial purchase, vessels with expectations beyond the boat show dock may consider such a system, comprised of standardised components.

Specific to the sailing catamaran installation problems, the geographical separation of the rudder and helm positions may be more expediently dealt with than by cable and pulley and the positive direct drive has none of the losses associated with hydraulics.  The maintenance may be confined to periodic inspections of the sealed grease filled gear boxes and fittings.  No chains, cables, hoses, tubes or associated fittings required.

The installation of shaft and gear box systems however doesn’t lend itself as easily to ‘after the fact’ installation.  The geometry of and clearance for components, gearboxes, torque tubes and drag links needs to be planned out before you get there.

At least one manufacturer offers extruded anodized aluminum componentry, allowing for some on-site assembly of items that may require adjustments to fit.  This also can save a lot of weight and reduces costs considerably.

This is an anonymous (Antares??) design for a catamaran application that illustrates some of the features possible with gearbox and shaft equipment as well as some general installation considerations.

1)      The tie bar function is assumed by the two drag links connecting the primary gearbox to the tillers.  This permits the tie bar to be discontinuous and less demanding in regard to straight line realestate.  It also permits either rudder to continue in use if its mate is damaged and disconnected.

2)      The swing angles of the main gearbox arm are greater than those of the tiller arms.  The resultant geometry produces more effective steering effort as the rudder angles increase, thereby proportionately reducing the load felt at the helm.

3)      The transmission system is very efficient with minimal frictional and minimal lost motion.

4)      The autopilot motor is directly mounted to the final motivator in the system and enjoys all the mechanical advantage of the proportional geometry.

5)      All of the components including the autopilot motor and tiller arms may come from one manufacturer.

6)      As long as you have ‘a plan’ the space occupied by the components is minimal.

7)      The actual steering loads are taken by the primary gearbox which must be solidly mounted.

8)      The rudder stops are integrated with the box itself precluding the need for separate structures by the builder.

9)      Regardless of the system type, tie bars or drag links may be subject to either side loads (someone standing on them), or extraordinary buckling loads (backing down on rocks with a rudder hitting first).  They are usually quite long and to help keep them straight in such circumstances, it may be expedient to have some kind of guides to limit their sideways displacement under compression.

10)   By providing a bail on the emergency tiller (required by ISO standard) you can rig the old string and pulley steering if you really have to.

Steering equipment gets no attention at boat shows, it is hidden away in stuffy compartments and not glamorous.  There is little incentive for a builder to do anything beyond what is barely essential, like shiny pedestals and wheels, additional expense is not in your face and readily appreciated.   Autopilots are commonly installed to order after the fact by sub-contractors with no factory participation in the engineering or quality control.  It remains for the boat purchaser to look at what he is getting, new or used.  Regardless of the style of equipment used, the quality of the hardware and its installation will be critical to the safety of the boat sooner or later.

All of the above illustrations have been taken from actual boats, most of them built by big name builders.  Unlike the purchase of a car, you can’t take the steering gear integrity for granted when considering a cruising boat, especially a catamaran with its particular steering gear design issues.

If you have read this far, you deserve some amusement.  Here are some irrelevant images.

For larger vessels a mechanical assist is often useful, sometimes essential.

Otherwise you may need more guests to help steer than you really wanted to provision for.

Once the crew’s personal steering effort possibilities have been exhausted, you may need to adopt some form of power steering,

the style of which depends on the prevailing power source and the acceptable weight limits.

One of these two was a spare.

This is the installation plan for the above hardware.  Either of the two steam engines could engage the geared quadrant.  Notice ropes and steam capstans just aft to steer with if all else failed.  Presumably the capstans also had bars so the crew could do the work the old fashioned way if necessary.  The assistant deck engineer and plumber are the first to hear if the steering gear crunches just outside their cabin door, that tells you something about the prevailing confidence in mechanical systems. (Note also that the 3^rd class passengers had ‘TV’(?) and a piano to distract them from the noise of the hardware just aft.)

By the way, yes this is the Titanic class vessel arrangement; evidently the ability to remotely steer in itself does not obviate the necessity to look where you are going.

We owe a debt of gratitude to those pioneers of the String and Pulley Steering System who risked their lives in flights of discovery, well before all the relevant theory was fully understood.  From these early experiments a method of yacht steering would evolve that endured right through to the latter half of the 20^th century and beyond.  In this archival photo record, the confident participants display none of the misgivings evident in the faces of the anxious bystanders.  Perhaps all the control interface issues we take for granted today were yet to be discovered, but the inspirational ‘2 in 1’ motto suggests that the dawn of the catamaran concept lay just over the horizon.

TC

We have these guys at American Retro Furniture to thank for their winning submission to the “Most Informative Diner Booth Photo” award!

Most Informative Diner Booth Photo

This is a very good illustration of some issues that the designer of your catamaran cockpit or saloon (marine) needs to consider, really.

1. Note the floor tiles.  Judging by the size of the deck shoes, I would say they are 12” standard tiles and by extrapolation, the seating for five occupies a floor space about 7’ (2.1m.) square.  That is a lot of territory in any boat.
2. The five at the table are a nice mix, but nobody looks like an ex college football hero (XXL) and it would be squeeze to seat anyone else.
3. The far corner is rounded out to give #5 a comfortable back rest and the two entry positions are rounded to allow the late comers to face the company.
4. The table edge overhangs the front of the seat by a few inches (40-50cm.), which is necessary to keep you from slopping soup on your shoes.  The table space is still only big enough for a round of cupcakes and coffee; the family plate will not get an airing.
5. Two of our demonstrators have been kind enough to sit on the bias, thereby swinging one leg each out into the void.  Everyone else is respecting the personal space of his neighbours by tucking his/her legs back under the seat front, (only possible if the seat risers are angled back).  At some point soon, someone will break the protocol and stretch out.  We hope they are sufficiently civilized to take turns, or are very familiar with each other.
6. The seat backs are not vertical and the seat bases are not horizontal.  Both have some built in angle.  These are comfy people.  The seating angles are appropriate for dining, playing cards or earnest discussions over a chart for example, to discuss where the diner should have kept to starboard.
7. The two peripheral guests are outsiders. Unless the lads on the end of the settee are obliging, this is social seating for a company of five, seven is a crowd.  Although there is seating for the extras, they are not well provided for socially.
8. Three of the five are captives; they should have gone pee before we left.  The consolation is, they will be obliged with service without being told to “Get up and get it yourself.”   If the diner hits an iceberg, they will be last to the lifeboats however.
9. In the event that too many liquids have been consumed and her friends have all left, could one of the girls keel over on a seat without falling on the floor?  It doesn’t look like it, something like trying to sleep on a plane by annexing the vacant seat next to you.

This is a good design within the parameters of its mandate; everyone is rightly proud and happily seated for a hamburger, fries and a Coke.  If you are looking for an efficient use of the floor space in your restaurant, and you like red, I would call this outfit. (Actually they also do other colours.)

But is this arrangement appropriate for your boat?  It may be if you have no other choice but we are talking catamarans (I am anyway) and by the time you are into the 40’+ range, maybe you can do better.  What will you look for?

There is usually one primary interior and one exterior ‘living’ space on a cruising boat.  Under various circumstances we would like those spaces to provide seating for dining, seating for lounging, working convenience for various necessary tasks (like taking apart the outboard motor), entertaining, and loafing.  We also would like those spaces to be pleasing to the eye and representative of our good taste (subjective).  Because we expect at some point to be ‘at sea’, the furnishings should have no rib fracturing projections or brow splitting edges.  If you reach out to grab some support ‘in the lurch’, something should be there to grasp and it shouldn’t come away in your hand.

How about this seating layout, does it work?

Setting aside the multitude of other design abuses represented (read rest of the blog entries), and the deceptive nature of the representation itself how would you critique the settee arrangements?

An upright, (non-lounging) minimally upholstered seat and seat back require a depth envelope of about 2’ (60cm) in width, (measure the seat you are sitting on).  By scaling the seat depictions, this cartoon represents a vessel probably about 61’(18.6m) in length and 31’(9.4m) in beam, lots of accommodation space to work with.

The average ass requires a seat envelope about 20” (50cm.) wide, (measure yours), and some elbow room in tropical climes, (where we are going), so you should allow about 24” (60cm) per person of ‘bench space’.

From this analysis, this vessel will seat eight souls at table in the cockpit (the corners are useless) and another five across from them with TV trays.  The two groups are about 4’(1.20m) apart (TV tray + passage space).   That’s a full thirteen bums to provision for.

Of the eight at table, two are free to get up and fetch food and drinks or take a pee.  If either of the middle two seated on the outboard side need to pee, at least three others have to winkle out from behind the table first, just to let them out, hopefully before they have wet their pants and the upholstery.  Of course any of the five seated on the port side are free to escape from behind their TV trays at any time and get to the head(s) first.

The good news is, once most of the guests have swum back to their own boats to continue drinking their own spirits, at least two very tall or maybe six very short non-swimmers can pass out on the 10’(3m) long seats and still be there for breakfast.

The inside settee/table arrangement appears to be a rotated version of the cockpit, (with some funny little scallops on the end seats?)  This setup however trumps the cockpit for lack of access with only one person free to serve etc.  The outboard end of the settee delivers onto the hull companion stairs apparently, (watch your step).   I suppose some kind of lottery is required to decide who enters the sausage machine first.

It wasn’t immediately apparent to me what the two purple blobs were in the port forward area of the saloon.  I thought at first they must be sinks for a galley to feed the multitude (minimum twenty-one at last count, plus cooks and servers).  The blobs however scale at about five feet across so I have decided that they would be too big for sinks, even under the circumstances, and could therefore represent chairs of some kind?, the best view apparently being that of the table antics.  If this is seating, there must be a sizeable galley elsewhere, but that isn’t pertinent to a discussion of seating.

The acres of dark orange appear to flat surfaces forming the deckhead over the hull accommodations.  The yellow is presumably the saloon floor, with about 12’(3.6m) of unobstructed tumble and roll run in either direction and 6’(2m) of distance between handholds or hip support;  over 100’²(10m²) of open floor space, in a boat no less.  The seating arrangement doesn’t contribute much to the security of moving around the saloon in a seaway.  Good for dancing maybe.

Party on!

Seating for 10 with table for 2

This is a common difficulty with artistic settee arrangements.  Sometimes it is unavoidable but be aware of the compromise.

Don't forget resale value when choosing upholstery

Sooner or later your boat will be out there; unique statements of your good taste may suffer a long spell of distain before just recognition as ‘retro’.  Maybe ‘classic’ style should be your preference in a boat as the lifespan is apparently indefinite.

The refrigerator liner look

Sometimes pulling a fiberglass interior liner out of its mould cheaply and easily trumps everything else, hence the refrigerator liner look, (the light doesn’t stay on when the door is closed).  Fiberglass liners tend to lock in design errors (mould expense) indefinitely.  How many ‘builder’s regrets’ can you spot in the picture above?   The upholsterers are often left to deal with the mess, creative lads that they are.

Sometimes it is a committee effort. Get the seasickness over with as soon as possible.

If you are going to adopt lounging (slouching) seat geometry, you need to think about putting your feet up etc.  You can’t eat and sleep in the same seating, just try pulling your living room chair up to your dining table.

Not your grandmother's dining room table

The table may be reduced in size to improve access but where does the ‘portable’ table space go?  It either folds (a geometric puzzle and shape constraint), or it must be removable (a stowage problem).   You know what a production it is to add leaves to Grandma’s dining room table, we would hope for something simpler on board.  Note again the interior liner moulding, this time a little less obvious.  Nice 80’s quality upholstery though, matching throw cushions (remember; go ‘classic’).

A perhaps too 'classic' upholstery theme

The liberal use of life rings in the décor may suggest a lack of confidence in the vessel, and the anchor motif may have financial connotations.  From this perspective, it looks like the table maybe a little wide when folded out?  Kinda homey though, ain’t it?  Well blow me down!

A new definition for the term 'legless'

New definition for the term ‘legless’.  Huh?  What gives here?  A séance lounge in hand finished endangered tropical hardwood and rich Corinthian leather.  ‘All for one and one for all’, sealed with a communal crossing of the shins.  Dumbassarrangement  unless you are singlehanding perhaps.

As comfy as a picnic bench

Whoa, forgot the seat backs!  That’s about as comfy as any picnic bench can be.  The foot room is occupied by a refrigerator so maybe it’s all for show anyway.  The ‘nav’ station appears to be the home for the French fryer, maybe the galley is a little small?  I guess the tongue of the settee is where you lounge while using the radios, chart plotter etc.  Don’t suggest a portable stool, please, especially with no foot well.  You can always provide lots of throw cushions and floral displays to hide any shortcomings, always pick bright colours.  Is it just me, or has ‘buttoned and tufted’ upholstery had its heyday (1950’s hot rods and basement bars)?

"I canna get the dilithium crystals under control Captain Kirk! We're exceeding waaaarp niiiiine!

Hey, sometimes you need a funny camera lens to fit everything in, but there comes a point when some perceptual deception creeps in perhaps?  Are the moulded deckhead refrigerator liner bumps really not straight lines?  This boat has dinette seating for eight, with demonstrated dining for four, provided you use short cutlery.  Watch the size of the place mats you pick up at Wallmart.  Rounded corners may be better.

An anonymous design

OK, this seating is accessible from either end.  The nav seat can also be swivelled into play.  Everyone can see out.  The table ends fold up and the whole assembly slides 14”(36cm) out from the corner to make space between the table edge and the seat front, which is what you need when the table lowers manually or electrically to coffee table height.  That’s as close as you can get to eating your cake and halving it too, (OK not so funny).   Most importantly, the TV is opposite the settee corner.  Don’t worry, that’s not the galley, it’s just an optional bar sink with washer/dryer in the corner.

Another anonymous design

Whatever shapes are adopted for the exterior of a vessel, they have to be harmonious with the underlying cabin design objectives.  A charter boat company may find it expedient to demand that a design provide banquet facilities in a cockpit area, knowing that sacrifices in the sleeping quarters below are of little consequence.  A little more balanced approach may be appropriate for your own personal boat, (illustrated above).  This particular design is known to have had 56 people on board at least once.  The foolish designer failed to provide sufficient seating, inside or outside.

Now that you are fully equipped to criticize catamaran seating plans, you can do your own Google ‘catamaran saloon’ image search and see all the rest of the stuff on offer, nothing is perfect but you can at least try, a little?

Now, the most asked question; “Why can’t I have a reclining chair on my boat?”

You can, you just need a space envelope about 7’(2.1m) x 2-1/2’(75cm) dedicated to no other essential purpose.  But,unless you are prepared to share, you probably need two chairs in fact.  Together they will occupy about the same space as the eight seat dinette you tore out to make room.

Once again, upholstery colour matters - amongst other things

If expense is no object...a better statement. A little harsh on the arm rest edges maybe. "It's the back tooth on the top."

Isn’t it nice to just enjoy your light and agile shallow draft catamaran while the rocks and sand visibly race by below the surface?  You have to wonder then if your boat is as light as it can practically be.  Is all that ‘essential’ stuff insisted upon for every possible contingency really necessary?

Scenic boating with the bottom in view

It could weigh your boat down unnecessarily.

Vessel approaches shore to embark early catamaran yacht design class

I think ‘agility’ should be a marine performance term, with agile, nimble, sprightly, lively; all being desirable descriptors.

Agility may get you off a lee shore, or help you manoeuvre smartly in tight circumstances.

Agility may be hindered by an excess of weight but, you know what they say…

 “You can’t have too much anchor chain!”

Chicken ship owner prepares to stow ground tackle selected for any contingency

“You can’t have too much auxiliary power!”

Early promotion for fireproof auto racing garments

“You can’t have too much watermaker capacity!”

OK, see, it's got pontoons, you can tow it along behind

“You can’t have too much fuel capacity!”

Hey you need fuel? Ok, I can get more fuel

“You can’t be too fashion conscious!”

Man with last year’s ‘kayak pants’ covets this year’s ‘float shoes’.

“You can’t have too much hot water!”

Vetus introduces tandem water heater designed for the serious cruiser

‘You can’t have too many batteries!”

“After I get done with the forward bank, I start on the aft.”

“You can’t have too many solar panels!”

“New solar powered electric hybrid catamaran (two he-hulls) donkey prod

“You can’t have too much gen set capacity!”

Honestly, does this set make my boyfriend’s boat look small?

“You can’t have too much entertainment equipment!”

Weight of early sub-woofer sinks entire French marina, life carries on.

“You can’t have too many navigation aid devices!”

Apparently missed 1 and 2? Note; careful boaters always attach a mooring line.

“You can’t have too many hulls!.”

A misconceived multihull concept runs aground. (Eight hulls!)

“You can’t have too many engine room accessories!”

Inflatable engine room ‘dolls’ give confidence to modern cruising vessel owner

“You can’t have too many engine gauges!”

Prototype Antares 44 helm panel, starboard engine bank

“You can’t have too many wheels!”

French charter cat experiments with visibility from multiple helm positions (12?)

“You can’t have too much accessory design advice!”

Design notes for the Antares MKII

“You can’t be too careful when confronted with clever equipment marketing!”

Hypnotic ad recently devised for unscrupulous marketing campaign

The equipment salesmen hardly have to work anymore.  Though their sales pitches may be tempered by at least some vestigial ethical sensibility, they will be conservative in contrast to internet opinion.

This latter source of endorsement is overwhelmingly motivated by (perhaps innocent) bragging.  This is a natural and acceptable aspect of the yachting mentality but a very subjective and unreliable source for advice.  The fellow who has just been sold an excess of something that he realizes too late he will be obliged to transport around everywhere he goes, is hardly likely to say, “That was dumb.” The first thing he’ll do is try to sell someone else on the idea, get safety in numbers.

Tubby offers provisioning advice on the internet.

Alvin is obviously the builder of Tubby’s boat

Remember, “You can’t have too much fun with her!”

Note; Resale value may be adversely affected by ‘statement’ hull colours and graphics!

And don’t forget,

“You can’t have too many ducks!”

Note: Melody always gets her ducks in a row

Ted,

Curious of your thoughts on this.  It came from one of the forum editors, his comments to me about ‘improvements’ to the 44i.

“Lots of alternator capacity to fast charge batteries, or a much better step … an engine mounted DC generator coupled with the Yanmar engine. In Europe it’s becoming popular to do that, it should be popular here soon. Yanmar has a product KMG65E that is a few inches wide and sits between the engine and the transmission, generating either 3 or 6KW.  This is far superior to charging your batteries while on the hook slowly with a typical alternator/diesel combination, or charging from a separate A/C generator with its own fuel and maintenance issues”

This is the Yanmar engine in questions: http://www.yanmarmarine.com/theme/yanmar/uploadedFiles/Yanmar-GENSET-KMG65E-E.pdf

Huh?

I am astounded at how easy it is to get others to do your marketing work for you.

The commentary above;  ”..a much better step..“, “..becoming popular..“, “..far superior..“, “charging…slowly..??”, is all unsupported by anything more substantial than pure enthusiasm from a very shallow brochure.  A non-appreciation for the technical, operational and efficiency implications involved should never stop you from standing on your hind legs and declaiming some opportune shortcoming to be rectified.  Here we go again.

Apparently developed for the sizeable European charter market, the ‘new’ Yanmar technology referred to above applies only to a few of their engine models and at present it produces 230v 50Hz power.  This alone makes it a non-starter for North American based vessels.  But wait, there is more, (did you doubt it?)

This idea has been ‘pioneered’ by Steyr who have had it around for several years as an integrated DC power system. They recently souped it up for the hybrid craze and made the output more versatile, offering DC or AC output for either side of the Atlantic.

The Steyr and Yanmar offerings place an electrical generating element between the engine and the transmission of a propulsion engine.  Heavy things are already spinning around at the back of the engine and the space envelope (especially the diameter) is mostly already conceded.  At a time when demand for on-board electrical power is over the top, it looks like a better idea than trying to drag even more DC power from belt driven alternators at the limits of their engineering or trying to fit a separate gen set in small vessels.

There is some engineering elegance to this idea and apart from some torsional vibration issues that must have required some serious head scratching, it appears to be a simple idea, quite a nice approach to take.

More Hybrid Hype
In their suggested hybrid application, the Steyr arrangement maintains the propulsion engine directly in the driveline and allows the ‘generator’ winding to reverse function and act as a motor to drive the transmission on occasion.  (This requires the added complication of a clutch in the drivetrain to disconnect the engine from the windings and transmission.)  Once the batteries are flat, the engine can take over and get you out of harm’s way with some real power.  This system provides an interval of (5 knots) running – expensively, inefficiently, but quietly, electrically.  As a penalty, you are compelled to take a whole lot of weighty, complex, costly stuff along for the ride wherever you go the rest of the time and accept the liability of an additional clutch function in the driveline.  I suppose if you boated a lot on backwaters this could add up. Their claim to be “emission free” and “green” apply exclusively to the intervals of electric propulsion, the rest of the time you are making restitution for that luxury plus the inherent inefficiencies – a selective definition of “green”. Nice looking brochure though.  As ‘hybrid’ ideas go, it is probably the nearest thing to a semi-defendable approach.

The Yanmar offering doesn’t go there at all, wisely I think.

Some issues and implications;
The generation of a particular AC frequency (e.g. 60Hz, 50Hz) is most readily accomplished by spinning a generator rotor at a fixed speed, typically a multiple of 1800rpm for 60Hz and 1500rpm for 50Hz, something like a record player that plays exclusively 45′s, 78′s, or 33′s.  This means that a propulsion engine that is also expected to generate AC power on the side has to run at a constant speed, so modulating the propulsion thrust and direction have to be accomplished by a complicated transmission system, e.g. hydraulic, electric, variable pitch props etc.

Ships with extraordinary auxiliary loads that rival or exceed the propulsion demands or require very versatile drivelines (e.g. icebreakers, cruise ships, dredges) will sometimes adopt such a system along with all the attendant complications and expense, this is nothing new but it has scant justification for a cruising pleasure boat.

To get around this constant engine speed requirement, Steyr and now Yanmar let the propulsion engine and generator rotor turn at normally varying speeds and take whatever messy power comes out and send it to an electronic black box, something like an inverter, to reconfigure it, clean it up, and deliver it as constant voltage, steady frequency, AC power.  The current available remains proportional to the rotation speed of the engine and windings.  The black box is subject to all the liabilities and inefficiencies of electronics, especially those asked to handle relatively high currents.  Two large cooling fans on the Yanmar ‘Power Box’ take away excessive heat (fuel burned).

The primary generating guts of the system fundamentally resemble an oversized alternator similar to the belt driven one at the front of the engine.  The difference is, the belt driven alternator puts out 12VDC power which has no frequency issue and is therefore insensitive to rotational speeds and requires minimal electronic control equipment.

Typical direct drive alternator plus belt driven model

You don’t get something for nothing.  Propulsion engines and their propellers are matched to push a particular vessel at a particular speed with a reserve for arduous conditions.  If you have to reckon on diverting engine power to generate electricity, the prop needs to be compromised to use less power with an accompanying alteration to performance expectations.  In the absence of variable pitch capability, the prop has to be sized to absorb the engine power minus the generating power.  You could arrange to do either/or but you then have to accept a compromise to the availability of power for both functions simultaneously at least to some degree.

Never trim nose hair while using compass!

The notion that running an engine at less than its full load is ‘highly inefficient’ is frequently exaggerated and theoretical rationalizations would often pay a dollar to save a nickel in the real world.  The diesel engine has a governor by necessity that only delivers enough fuel to maintain a given rpm.  This means that the fuel used is always strictly proportional to the load, they cannot run ‘rich’.  The working load includes the parasitical stuff like oil pumps and water pumps plus the friction and heat loss, which will be larger for a larger engine.  If the working load is proportional to the engine’s power capacity, the combustion physics (temperatures and pressures) are idealized for the design and the best fuel efficiencies are achieved.  If the working load is relatively pathetic, the combustion physics will not be realized and some fuel/work done inefficiencies will be apparent.  So, running a dedicated 12hp diesel gen set engine with a 6kW load would burn significantly less fuel than would a 55hp (as in the Yanmar) or greater diesel propulsion engine running in neutral doing the same thing, especially as the transmission guts will be idly spinning as well and generating some heat. A 6kW gen set actually spends the majority of its time running at much reduced load so the proposition is even less attractive.  The need to generate electrical power at amounts relatively low in relation to the propulsion power is the reason we use a relatively small gen set engine, this has to be kept in mind.

Keeping installed horse power proportional to the task...

The functions of propulsion and power generation are too diverse in load to happily co-exist with a common engine power source.  You could power your car with your lawnmower engine or your lawnmower with your V8 car engine, but should you?

Generating variable electrical power, sending it to a black box inverter and sending it from there to a battery charger in order to make 12VDC for the batteries involves heavy inefficiencies and liabilities.  This makes the enthusiastic but misconceived idea presented at the top of using DC power from Yanmar’s equipment rather peculiar (Their own marketing concentrates on running AC hair dryers, coffee machines and the like, but does it mention battery charging?? unfortunately).

Current standard issue belt driven DC alternators are putting out up to 115amp (Volvo). They will do the battery charging job directly and automatically in any case if the engine is running.  This makes the battery charging advantage as suggested a non-starter, the function is already in place.  The concept of integrated high capacity DC generating capability, (Steyr’s initial offering), by perhaps making a belt driven DC alternator unnecessary is an elegant concept, but it is hard to match the serviceability of the relatively cheap and ubiquitous automotive alternator.

Typical alternator repair franchise, found worldwide

When space is available, placing a small gen set in an extremity of the vessel and/or in a dedicated sound enclosure has to be more pleasant to live with than running a propulsion engine.  Both mechanical and exhaust sound, heat, and vibration generation are all proportional to size of the engine and it is virtually impossible to fully sound enclose a propulsion engine with its attendant driveline.

The charter business that motivated Yanmar’s investment (apparent from their glossy brochure), works on different principles than the yacht owner would apply.  I have worked with both parties.  The ability to offer AC power without resorting to a costly and sensitive inverter/battery or a gen set installation is highly attractive and in the circumstance that the operators are not expected to have any comprehension of or responsibility for the equipment, a considerable compromise to functionality is quite acceptable.  The charterer walks away from the boat after having enjoyed a week of blow dried hair.

Famous yachtsman/record producer Phil Spector after successful yacht charter

I have always liked the idea of using the flywheel space/weight to generate power. The Steyr arrangement caught my attention initially and I noted with interest the recent offering from Yanmar.  This concept is however only a part of a much more comprehensive puzzle.  I can make a case for any kind of mechanical arrangement but I expect all of the puzzle pieces make a complete picture.  The new Yanmar and Steyr technology doesn’t quite fit any picture I am currently working on but maybe it will some other time.

The reconciliation of a lot of complication is what we would all like to see.  Taken in isolation, all of the ‘new’ ideas sound marvelous, especially with a cool marketing spin.  Unfortunately we are faced with two or even three voltage electrical systems, escalating expectations of luxury, equipment adapted by necessity from other larger domestic and automotive markets, world-wide service and supply issues, the necessity to keep systems within the operational capabilities of average citizens, the imperative to push the boat reliably through wind and wave, and all this while minimising the investment risks for both the yard and the owners.  If a system doesn’t work well and comprehensively, we are all in the soup.

As soon as I see a responsible way to ditch a lot of hardware, you will be first on my list to get a sales pitch.

Meanwhile, let’s keep our ducks in a row.

TC

Melody considers her marine electrical equipment options

Answer: There is one mast and standing rigging configuration (height & geometry) available for the Antares that was initially engineered by Selden Spar and has been used successfully since inception. Some options in sail handling have been added to accommodate different owners cruising preferences.

When the design was first being developed, a stability study was undertaken to establish some parameters to apply. The company always had a very close relationship with its customers and the prevailing philosophy demanded that the new boat could be handed over with confidence to its trusting owners.

The sailplan / stability design exercise pre-dated the establishment of any benchmarks such as the ISO Standards now offered for offshore Category A vessels so we used experience with the company’s other existing designs and charted the sailplan/hull parameters/wind speeds to establish a threshold that we knew would be safe and forgiving to the maximum degree that could be practical. This was, in effect, full size model testing.

A hypothetical sailplan was frankly ‘eyeballed’ to start with, (my task being to adjust the drawing while the sailplan ‘committee’ leaned over my shoulder). This provided some sail areas and centres of effort to consider. The large sail areas caused some chin massaging but they were deemed to be acceptable, just. The stability numbers were checked against the chart we had developed, an exercise that engendered a lot of ‘ultimate case’ imagination, speculation and debate. Of course the potential for the drive power of the sailplan continually tugged things toward the adventurous side of the equation. Things were adjusted a little but at foundation, the ‘eyeballed’ rig stood, a testament to my colleagues sensibilities.

It wasn’t until this exercise had been run through that the height of the mast truck off the water was measured and fortuitously found to be acceptable for transiting the ICW. I suppose that if it had been with a foot or so we would have reduced it, but this just wasn’t necessary. There was certainly no compromise, the sailplan as it still stands was considered to be adventurous enough.

The standard mast carries a luff track for a fully battened mainsail. The boom is provided with extensive internal hardware and tackle for two ‘single line’ reefing systems. In common with all modern catamarans in its size range, the boom is fairly high above the deckhouse. Several years ago we developed of an optional MainTamer boom which consists of a set of light weight laminate ‘wings’ attached to the standard boom that in effect provide a platform to contain the mainsail folds so they don’t tumble about. The sail itself remains the same fully battened high roach cut and hidden away inside the MainTamer is the standard Selden single line reefing boom. If you were to break the MaintTamer in some remote location, the boom may still do its job and be readily serviced.

The optional ‘new’ element for Antares is the Selden in-mast furling system which primarily involves the mast extrusion itself. The external hardware, appearance and dimensions of the spar are essentially the same. The boom extrusion is in common with both configurations but the internal provisions for single line slab reefing are absent. The mainsail has been designed by North Sails specifically for the Antares and is well within the maximum capacity of the mast system. By necessity, sail battens in a furling main must be parallel to the mast rather than the boom, as is the case for the slab reefing sail. Although full length vertical battens could support a roach similar to that of the standard mainsail, practical issues preclude such awkward stuff on an ocean cruising vessel, (imagine a raising/lowering exercise with 40′+ battens to handle). The North Sails design therefore accepts the relatively limited roach that may be supported on a series of short vertical battens. This is a compromise to the total mainsail area of approximately 30%.

For many years, the Antares was not offered with a furling main option, despite the considerable interest expressed by customers. There were two primary reasons for this; the prototypical nature of the gear on offer and the compromise to the mainsail area. Recently, both of these reservations have undergone some re-thinking.

For over ten years, Selden spar and rigging engineering has been incorporated closely with our own production engineering, forming a kind of mutual investment structure. Over the years we discussed the furling main issue periodically and it was with some satisfaction that the announcement was made that Selden was ready to offer the equipment. This was critical to us as our boats are dispersed all over the world at any given time and the knowledge that the Selden network may be available for assistance to owners as well as ourselves is an essential. Simply put, we (and our customers) needed Selden level support for any venture into furling mainsails. We now have it.

The move to produce our boats in Argentina led to the development of a working relationship with North Sails Argentina. This provided access to some fresh and considered opinion from the world class sail loft.  Turns out the perceived loss of push from the reduced roach may not be all that significant a factor for our cruising boat; in a set with large headsails the proportionate effect of the main is significantly reduced along with the compromise due to a reduced roach, the limited crew and sail trimming effort likely to be available very much reduces the potential for a maximized performance main, and the relative ease of furling means the sail will actually be used a lot more.

This last point is probably the most significant and is echoed by Selden experience. Faced with the necessity to remove its cover, release the gaskets, go through the hoisting process with a possibility of shortly having to drop or reef sail and reverse the process, owners are justifiably reluctant to use the main much of the time, especially when it involves excursions out into inclement conditions. The furling main with its electric deployment from the helm gets used a whole lot more. This means the contribution of the sail over a period of cruising is much greater, isn’t that really ’performance’?

In ideal conditions you may lose a little speed and that may be significant to your style of sailing. There is no meaningful way to quantify that loss as it will depend on the sails set, wind conditions, point of sailing, your motivation, etc.

Regardless of the theory which will be debated back and forth endlessly from different perspectives and by any number of us ‘experts’, the fact remains that the recent Antares boats equipped with furling mains delighted their owners, (despite our skepticism and reluctance). Acknowledging that they can’t instantly try different sail styles in succession they however report no apparent loss of perceived ‘performance’. I believe this is all that can be asked for, so we gracefully concede the field and say, “The furling main is a viable option for many if not most owners.”

Putting yourself in an owners shoes, and the rest of his foul weather gear, and perhaps letting go of some things that you considered ‘de rigueur’, is the only tenable evaluation exercise. The definition of ‘performance’ for a cruising boat may acknowledge racing sail parameters but needs to encompass and be weighted toward the compete voyage experience.

The full roach, slab reefing, fully battened mainsail system is there for owners who can enjoy the advantage of it. The reduced roach furling main is there for a more practical approach. Which configuration will arrive at the next port first is debatable.

TC

Answer: Your question is one that occurs to everyone at various times in the design process, ‘What is the weakest link, and can I plan for it to save the day?’ It only seems to work for electrical systems, in the form of fuses. Tangible things tend to store up a lot of energy in the process of reaching the overloaded state, releasing a lot of backlash when failure occurs, and broken stuff on board is usually broken for good.

Designing something to fail at a particular threshold flies against another pillar of engineering practice; the margin of safety. Most engineered items on the boat are 2 to 3 times as strong as the theoretical calculations suggest that they need to be. This is contrary to race design practice; ‘If it doesn’t break, it’s over engineered.’ Working equipment, including cruising gear, has to be built with forgiveness of;

• miscalculation or incorrect identification of the true loads,
• equipment degradation over time,
• inadvertent extraordinary loads,
• misuse or accident.

The possible dropping of a tall and heavy mast and rig with consequent structural damage and encumbrance of the vessel’s seaworthiness as it bashes away alongside or underneath represents a real threat. This likely scenario would not balance well against the unlikely capsize scenario. (Once again, what margin of error should be applied to deciding a breakaway strength?)

There have been attempts to invent sheet release mechanisms that I believe you may find discussed at the Amateur Yacht Research Society (AYRS). The absence of such gear from the gadget loving market (which is not entirely stupid) indicates the level of success/acceptance achieved. This type of gear always has consequences that may be as bad or worse than the one targeted and I believe that is the fundamental impediment. You can burden any function with sufficient devices to ensure its ultimate safety, it doesn’t work anymore and just becomes part of the landscape.

With the exception of monohull sailboats with external ballast keels, virtually every other thing that has ever been identified as a boat or ship has been subject to capsize without any expectation of recovery. For some reason catamaran cruising boats take particular criticism that would be equally applicable to fully rigged clipper ships, or even cruise ships. (Best stay on shore I expect.)

The primary reason (among many) to adopt a stable cruising catamaran design is the absence of several tons of essential lead ballast that tries, from the day the sailing monohull is launched, to drag it to the bottom. Sailing monohulls spend most of their time in a semi-capsized condition; they persist in cruising application primarily due to love of tradition and entrenched misconceptions. The threat to personal wellbeing in every regard that this vessel configuration engenders would not be endured in any other application. Capsized monohull sailboats are inevitably dismasted in any case by the exercise with consequent structural damage and loss of integrity. Perhaps they should be equipped with breakaway keels so the wreckage might float, and you can have something to hang on to? Bobbing around safely and indestructibly appears to be an attribute exclusive to the ducks.

Please do not equate the marginal stability of the sport catamaran (of any size) with an appropriate cruising design. The misapplication of race design rationale, though attractive to marketing, is counterproductive and possibly dangerous to cruising. I believe that is the real underlying issue in regard to ultimate survivability for vessel and crew. At the other end of the scale, having worked on self-righting rescue lifeboat design, I know that giving top priority to survivability in ultimately bad conditions will result in a bizarre vessel that is otherwise a burden to own and operate, and still there are no guarantees.

To go back to your question, one would like to see the shrouds and all running rigging miraculously and safely part, just as the weather hull cleared the water, leaving the spars etc. free to make a clean exit to leeward, but in practical terms this is impossible. The loss of the spar would be a very dangerous and messy event with ongoing ramifications.

Despite the action photography we strive for that captures our cruising cat cutting through the waves at just the right moment, the impression of ‘flying a hull’ is just that, an impression. You are very unlikely to get a cruising weight catamaran hull to lift like a beach cat. If it does, you are pressing the envelope rather severely, but hey, take a picture for us!

We believe that the vessel should do its best to take care of its crew, regardless of their level of experience and are confident that the vessel we offer demonstrates the best effort and rationale to achieve that.

Good question though, wouldn’t it be nice? How about explosive chainplate bolts? No wait I didn’t mean it!

TC

Catamaran design school commencement

You really ought to get the steps right.  We have personally witnessed three incidents of would-be boaters falling down the stairs of various creampuffs, not underway but at the boat show docks.   Maybe their attention was diverted by the prevailing glitz.

It isn’t that difficult to figure out what should be done.  Staircase design standards are well documented and if you are not sure, you can go out and measure a few.

But designing good step ergonomics often results in a major conflict with a vessel’s rocketship visuals, step lines being generally transverse and not suggestive of speed.

Sometimes the proliferation of lines constitutes a design challenge

The catamaran with its multiple accommodation deck heights is a challenge.  The relationship between riser height and the tread width, in combination with the step overhang needs to fall within a set of parameters that are derived from human anatomy.  The variations in that anatomy are quite significant; the step up ability of a woman of small stature varying significantly from that of her ex-football player husband of 6’4”.  These people however represent the potential boat owners the designer should serve.   The alternative…

Forcing the owner to fit the boat design

Continuing with the funhouse theme, remember the moving stairs and slanted floors? Does this remind you of your monohull boating experience?

The diagram above illustrates some of the issues pertinent to designing domestic staircases to avoid homeowner tumbling syndrome.   Your household staircase doesn’t tilt and heave and get slippery as you may expect your boat’s to do but there are no published standards for pleasure boats.

Humanscale

Obviously some compromises need to be made to avoid having your catamaran yacht resemble a tour boat but where should you draw the line.

Marine companions and stairways often have to be closer to ladders but this application is not without recognized correct design parameters.   We all owe a debt to Neils Diffrient , an ergonomic researcher who systematically researched all aspects of human interaction with the physical surroundings.  His work, (unfortunately currently out of print) has been used for the responsible design of everything we sit on or at, climb on or through, push buttons on, view, etc.  When something isn’t comfortable, convenient, within visual range or easy to reach you may be sure that N.D.’s works are not in the hands of the designer, or perhaps he just doesn’t care to know.

To the left is a lift from part of Neils Diffrient’s Humanscale study of the ways in which we may transit changes in elevation.  The reproduction is unfortunately poor but the little chart in the lower right relates the parameters appropriate for different people and establishes workable averages.  This is thorough work, if you follow it, your catamaran steps will work.

Probably a dumbass idea all around

Making a stairway ergonomically correct does not preclude a tasteful and romantic vision.

The Antares 44 companion stair leading down from the saloon to the owner's suite, as the designer envisions it

When you go on board a catamaran, have a look at the deck height transitions and traffic patterns first.  Don’t consider the transom steps in isolation, they are the way on and off the vessel whether it is at the dock or on a mooring.

consider arriving on the dock with an armload of groceries and trying to board an arrangement like this one. (the ability to do the splits is always appreciated on the dock.)

You will often see vessels with giant height transom steps all the way up to sheer height.  The designer has been faced with limitations as to the stair run envelope, (eg. saildrives below, aesthetics, quarter mounted helms, etc.) and has decided to sacrifice good ergonomics.

If the traffic pattern has been thought out and the relative deck heights configured appropriately, the stair requirements will be naturally minimized.

The parameters for landings, tread dimensions, foot stops etc. that apply to safe shoreside stair design shouldn’t be ignored for the sake of cleverness or imagined ‘design statements’.  We make necessary concessions for small vessel design but the standards for ship passageways and stairs are more stringent than those for commercial buildings, for obviously sound reasons.

Unhappy compromise

But are you willing to set aside good ergonomics and thereby risk injury on board your own vessel, just to satisfy a designer’s notion of ‘style’?

Sometimes everything is just plain wrong

Cool (the requisite ice pack, I mean)

As a catamaran builder you need to be stair conscious, it goes with the territory, well usually…

varying step heights

Varying the step heights within a set is recognized as a certain way to confuse the motor reflexes, (yours, not the engine’s).  Ideally, neither the riser height nor the tread width should vary more than 3/8” from step to step.   Maybe this case is an optical illusion?  Having a glazed hatch in the landing area and a port in the kick zone is unfortunate.

You don’t need a tape measure at the boat show; your brain is already well aware of your anatomical comfort zones.  If you walk all over a potential dreamboat, from water level to the highest deck surface, inside and out, and remain unconscious of having traversed the multiple transitions in altitude, the designer had you in mind.  But if you stopped to ponder a possible safe descent, search out a missing handhold, lift a knee up to your chin, tripped, stumbled, climbed, clambered or ducked your head too late, you are being had.

Keep in mind you may have to get to every corner of the vessel, even the masthead, in the dark, cold and wet with the decks and stairs moving around, just like those in the funhouse you remember.

Do you want your boat to represent your adventure or the designer’s?

designer steps

Questionable deck and stair arrangements are not confined to the fanciful magazine ad computer renderings or one-off boat projects.  They are frequently incorporated into many big name production vessels.

Just watch your step.

TC

The overabundance of opinion and baloney proliferating on the web makes me reluctant to participate in the melee but some limited commentary may assist our customers in assessing the true relevance to their own cruising catamaran experience.

The really notable part of this story is the level of its exposure.  If it concerned one of the numerous keelboats that get knocked down and sunk by its ballast in a matter of minutes, it would be the same old story and we would never hear of it (even if anyone lived to tell).   The proportional loss of life in the multihull fleet must be miniscule compared to the level of reportage.  In this case no lives were lost and the tale is freely told.

The Story of S/V Anna
Setting
The Event
Immediate Aftermath
Rescue
Post Rescue
Final Thoughts
The Rescue Video
My Thoughts – Comments by Ted Clements

Here is The Story in its entirety as received with some formatting adjustments;

The Loss of the S/V Anna,

Atlantic 57 Sailing Catamaran

Designed by Chris White.

On July 31 – August 1, 2010, Anna was lost in a sudden violent storm between Tonga and Niue, and Glen and I were rescued 17 hours later by a freighter.

Personnel

Glen McConchie, 46, Kiwi.
Kelly Wright, 58, Yank.

Setting

On Saturday, July 31, 2010, about 10 a.m. Tongan time, Glen and I escorted John, our third crewman who was returning to the US, to a guestroom in Pangai on the island of Lifuka in the Ha’apai chain of islands in Tonga, then returned to Anna and hauled the anchor and set sail for Niue, about 250 nm away to the ENE. The winds were from the E and the SE so that we had to beat into them and tack a few times. The winds were fairly constant, ranging from about 12 to about 20 knots, and the skies were almost totally overcast, although there were moments of sunshine. The winds had been stronger, in the 20s, for several days prior and the seas were quite lumpy so that we put the first reef in the main but used the full jib. We also used the lee daggerboard. These conditions prevailed for over 24 hours.

The Event

The following day was Sunday Tongan time, but because we crossed the International Date Line and our destination was Niue, we changed our ship’s time (as displayed on our main clock and all the navigation instruments) at noon to reflect Niue time, so that Sunday became Saturday, again July 31st.

With a crew of two, even if off watch one tends to remain in the pilothouse unless sleeping and be readily available to assist, and such was the case that afternoon, as I had the noon to 1800 (6 p.m.) watch with Glen right there at my side in the pilothouse. Sometime after noon we were on a starboard tack and were finally able to achieve a good layline to Niue so that we would no longer have to tack, and things seemed to be going our way. The skies were still cloudy but some time after 1400 we noticed that a portion of the cloud cover to the East was especially dark. I turned on the radar at the 12-nm range and it showed rain clouds almost all around with rain clouds to our NE, E, SE, and NW, but the radar displayed no apparent difference or special intensity in the dark cloud. Nevertheless we were somewhat wary of the dark cloud and paid extra attention to our monitoring of the weather. The barometer had dropped only from 1000 mb to 998 mb over the last few hours, which was no cause for alarm, and I hoped that the dark cloud held intense rain that would wash the boat and knock down the seas so that we could shake out the reef in the main and speed up.

Suddenly just after 1500, while observing the anemometer (wind speed and direction indicator), which was displaying apparent and not true wind since we were beating, I noticed that the wind was backing to the S so that rather than beating into the wind, suddenly we were on a beam reach. I began turning the autopilot so that we would remain heading up. Then the wind speed jumped from 18 knots to 25, then to 30, then to 35 in the blink of an eye, both Glen and I yelled “let’s reef” and we bounded out into the cockpit. When I saw the anemometer in the cockpit a couple of seconds later, the wind speed showed 45 knots, so I moved to the autopilot and again tried to head the boat up into the wind, while Glen tried to reef the jib. The wind was ferocious, however, and Glen could not control the jib outhaul line so that it started flapping wildly. I was afraid we would rip the sail (which I did last year because of my own operator error) and so shouted at him, “What are you doing?”, then reached over and closed the jammer cleat that prevented more line from getting loose. Realizing finally that the wind was overpowering us to a perilous extent, I next moved towards the mainsheet to release it, but in a flash we were up in the air, flying a hull as if we were on a Hobie Cat, and I lost my balance and started tumbling to port. We hung at that position — roughly 45 deg. — for a second then over we went. I used the S word. Loudly.

Later Glen said that the highest wind speed he thinks he saw (he is not entirely certain) was 62 knots, and that was some moments before we were blown over so the wind speed was likely much higher.

Immediate Aftermath

I found myself in the water underneath Anna somewhere. I had fallen out on what started out as the lee side of the boat but which, when inverted, became the windward side. I remember struggling, seeing various things swirling around me — blue, white, dark, metal — and I hoped I would not get entangled and swam underwater to get out from underneath the boat as best I could. I surfaced on the windward side and swam to the stern of the boat, thinking to myself, “better play this one right”, but was not panicky and was surprisingly clear-headed, thinking that I should have released the mainsheet and other should-ofs. I quickly climbed aboard Anna’s inverted wingdeck that bridges the two hulls. In my memory the sun was shining and there was no wind, the seas calm, but that must be erroneous and perhaps it was just a sense of relief of not being swept away coupled with the relative protection afforded me being between the two hulls.

My first concern was Glen. I was standing or kneeling on the inverted wingdeck and looked around for him but could not see him and worried that he could not hold his breath that long. I moved over to a hull and started pounding on it, yelling “Glen! Glen!” Momentarily I heard an answering series of knocks, and I felt mega-relieved and a surge of confidence swept over me. In each hull of Anna there is an emergency escape hatch, which is basically a window under the steps that lead from the pilothouse down into the hulls. Soon Glen’s shiny head appeared in the emergency escape hatch of the starboard hull, now to port, and we gave each other the thumbs up sign. Although he could not hear me, I somehow made it clear that he needed to activate the EPIRB (Emergency Position-Indicating Radio Beacon) to notify authorities of our emergency, and he nodded assent and disappeared from view. Later he came back and tried to break open the hatch with a hammer and then a fire extinguisher, but was unsuccessful. (I may have the timing wrong: it could be that he tried to break the hatch first before moving off to activate the EPIRB.)

Whereas I had fallen out of the cockpit when Anna capsized, Glen had remained in it, probably holding on to railings around the binnacle. He found himself in an air pocket and simply turned around and with some effort and patience fighting the surging waves, was able to time opening the door just right and re-enter the pilothouse where there also was a pocket of air, although it was quickly diminishing.

Ultimately I saw that it was unlikely that I would get back inside Anna without having to swim underwater and to enter via an open door or hatch or port. I did not want to do that, so I looked around and tried to determine how best to shelter myself. I remember it being bright and sunny and quite comfortable, but again I doubt my memory. Soon I came to realize that there was another venue for my survival besides trying to remain on the inverted deck or getting inside of one of the hulls, and that was our RIB (rigid inflatable boat) dinghy that was floating right there at the stern of Anna. I suppose it was there when I first climbed on but I do not remember it as I was focused on locating Glen, but when I finally noticed it I immediately recognized the dinghy as my salvation. We had parked the dinghy on our aft deck, as was our normal practice, during the passage from Tonga and it was still attached to the dinghy davits. Evidently on capsize she popped up and self-righted for when I first saw her she was floating right side up.

I moved to the dinghy and got in her and began securing her with additional lines to Anna, which I knew would not sink. Ultimately I tied four extra lines from the dinghy to Anna around a stern rail, the rudder, and the saildrive, and then tied a line around my waist and secured it to the dinghy to prevent me from being swept away. Seas washed over me, filling the dinghy, and for a time I stayed busy bailing but soon determined that bailing out the dinghy was a useless waste of my energy, that water came in much faster than I could keep it out, and that the dinghy, being an inflatable, had enough positive buoyancy to stay afloat even if full of water. Luckily we had anticipated that the dinghy might someday be swept away or its outboard not start, so we had loaded some emergency supplies in her small anchor locker, and I now had them to rely on. In the anchor locker I found, besides the dinghy anchor and about 50 feet of anchor line, a floppy hat to keep the sun off, some tools for working on the outboard, a liter of water, a knife, and — most importantly — a handheld VHF radio. Except for the floppy hat I left everything in the locker and shut it tightly for I was concerned that the waves that were battering me would wash something away. I intended to preserve everything as long as possible because I had no idea how many days we would await rescue.

On the floor of the dinghy we had also put several items, like a fishing net, a plastic container full of salted-down cut-bait for fishing, a bucket with a sturdy line, other spare lines, and — most importantly — the awning we used on the aft deck. It was that awning that prevented me from perhaps suffering hypothermia that night, as all I had on was a pair of shorts and undies underneath, and waves were constantly washing over me, chilling me in the strong breezes that relentlessly buffeted me.
For several hours I was not sure that Glen had successfully turned on the EPIRB and regretted us not practicing with it. Finally, though, darkness fell and I could see the flashing light of the EPRIB through one of the escape hatches, and felt relieved to know that someone somewhere had been alerted that we were in a emergency.

Riding in the dinghy was very uncomfortable. I compare it to being in a thousand fender benders, because the dinghy was ceaselessly slamming into one of the hulls and bouncing on top of the wingdeck, then would float free only to fetch up with a violent jerk on one of the lines. Moreover, waves were constantly swamping me, ripping the awning out off my hand while I used the other hand to hold on. I counted for awhile and the most I was getting at one stage was about 12 seconds of peace before the next shock. The shocks were so violent that the 15-hp Yamaha outboard broke off its swivel and fell into the depths of the ocean, I suppose due to metal fatigue. It was absolutely the most miserable time I have ever spent, and if I had been forced to suffer another day of that I don’t know if I would have been strong enough to take it. I intended to try something different when dawn came, although I did not know exactly what. I tried every position imaginable and ultimately discovered that sitting on the anchor locker and hunkering down with the awning draped over me was the best position since it allowed me to sit as high as possible in the foot or so of water that sloshed around inside the dinghy. As I write it has been a week since we were rescued and I am still stiff and bruised.

Glen did not have it much easier inside. Fumes from the starting batteries wafted through the hulls where air resided, and Anna was getting knocked around herself a great deal and there was broken glass and dangerous items like our galley cutlery floating and washing about. He suffered the worst wound, a nasty gash right on top of his bald head. And while at night I had some light from the moon and stars and could see everything quite clearly, Glen was in total darkness except for the EPIRB’s strobe every three seconds.

Anna has a survival pod in each bow that stayed dry, and it was in one of those that Glen spent most of the time. He too was planning for the next and subsequent days. Although the pilothouse was filled with water, Glen ventured from hull to hull during daylight, tying a line between the hulls so he would have something he could pull on as he moved between the hulls. The boat being upside down was disorienting to him, he said, and it took him several attempts before it became clear to him that what had been starboard was now port, and vice versa, and to locate the EPIRB so he could flip the switch and activate it.

I am sure had we not been rescued in such a timely fashion Glen and I would have improved our living conditions on subsequent days for we had ample food and water in the hulls.

Rescue

At midnight — about nine hours after the capsize — I heard an engine. I opened the awning I had wrapped around me and looked around and saw strange lights in the air just a few hundred feet high moving away from us. I hurried to open the dinghy’s anchor locker and fetch the VHF, and I turned it on and start jabbering to the aircraft crew that they were to the North of us, that they had missed us, and please come back. “Anna, this is Kiwi Rescue Aircraft 4, and do not worry, because we have an excellent fix on your position and know exactly where you are.” I knew we were saved then, but felt no great sense of relief.

It was an Orion aircraft, not a helicopter which I had been expecting, and I was a little let down because I realized that this aircraft was not capable of performing a rescue itself but could only locate us, so that rescue was some time off yet. Sure enough, on asking about rescue I was informed that a freighter had been diverted and would arrive the next morning.

The aircraft came by every hour thereafter and checked on us, and I talked to them via the handheld radio. Occasionally they set off green flares which they had told me earlier was a sign they wanted to talk, but they could have saved the flares because I was eager to talk and called them as soon as they appeared on the scene.

The night passed incredibly quickly, I suppose because it was such an active time with constant recovery from waves and jolts and because once I knew I was going to be rescued I was no longer worried about it. I used deep breathing I learned in yoga to fool myself into feeling warm, telling myself that the deep breath was going from my lungs to my midriff and hips and that the breath was bringing warm air to those parts of my body. For a couple of hours before dawn the seas relented, and whether it was a dream or hallucination, for a moment I thought I was sitting in a dry dinghy with boxes of dark chocolate lined up symmetrically on either side of me. I never once took a sip of the liter of potable water that I had in the dinghy, preferring to save it in the event our rescue was prolonged, but early I did nibble on some of the cut-bait to test whether or not it made me sick, but it was so salty I spit it out and determined to worry about food later.

Dawn came, the seas started building again and knocking me around, and the Kiwi Rescue Aircraft appeared, this time with a different crew whose English was much more difficult for me to understand. I was informed that Glen would have to make it out of the hull on his own, and that he and I would have to swim to the freighter where the crew would be waiting with lines and lifebuoys. I had not been in visual contact with Glen yet that morning so I had to leave the dinghy and make my way to the emergency escape hatch where I had last seen him. I was still tied to the dinghy so I knew that I would be alright, but the waves knocked me down and swept me away and I instinctively grabbed onto a steering cable with one hand in a vain attempt to stay near the hatch. I had the grapnel anchor in my other hand and beat like hell on the escape hatch for a few seconds, then would be swept away and grab a cable and water would wash over me, then I would make my way back and hammer away again, and then I would be swept away again and I would grab hold of the stainless steel cable that bit into my hands and the force of the waves would push me underwater and twist me around so that holding on the cable proved impossible. I thought I might drown at one point so I made my way back to the dinghy to recover and wait, hoping that Glen had heard my occasional hammering. Because he did not appear, I resolved to try again, only this time not hold the steering cables, but just beat on the hatch as I was passing by, not fighting the waves but riding with them and do the best I could. I did that for a few minutes and soon Glen reappeared and I quickly returned to the dinghy and from there, in a very demonstrative sign language, communicated to him that in twenty minutes the freighter would be in position and that he — Glen — would have to get out the hull on his own.

I waited patiently wondering just how Glen would evacuate the boat and begin to worry when I did not see him after several minutes. But Glen was just taking his time, trying to assure that he would not be entangled in any of the rigging. His best means of escape was to use the deck hatch of the sail locker which served as his survival pod, but the deck hatch was no longer on top of the hull but was instead on the bottom, in the water. Glen wisely tied a line to an empty jerry can and pushed that out first so he would have something to grab if necessary to prevent him from being swept away. That popped up and I started calling his name and soon he appeared with a mask and snorkel and his dive knife strapped to his leg, ready to cut through any entangling lines. He made his way to the stern of the boat, I still in the dinghy tied to one hull, he holding onto the other hull, and soon he was able to climb onto the hull and hold on to the upside-down rudder. We chatted a bit.

The freighter was moving close so that we were drifting down on them and the crew was shouting at us and showing us the lines and buoys and the net and ladder we ultimately would have to climb. When the freighter was a hundred feet or so away, I stood up, ripped off the floppy hat and flung it into the water, then told Glen, “here I go, good buddy”, and dove into the sea and began swimming. As I approached a crewman tossed me a line, then another dropped me a life buoy, and they started dragging me aft towards the net and ladder that was set up near the superstructure in the rear quarter of the ship. On reaching it I had to wait until a wave picked me up and set me high enough to get a foot on the ladder, then climbed aboard, maybe 15-20 feet, with some difficulty where a crewman wrapped a blanket around me and another held on to me in case I would collapse.

Glen stayed on Anna longer than I and was nearly smashed between the freighter and Anna, and pulled a leg up just in time to suffer only a small cut, but no broken bones. Glen waited for a wave that swept him up and clambered aboard the freighter just behind me. Whereas I shook the hands of the crew, Glen embraced them in a spasm of joy and relief.

I was rescued with only the shorts and underwear I had on. Glen came aboard with shorts and undies, but also the scuba knife strapped on his leg and, at the last minute, he picked up the floppy hat I had been wearing and had tossed into the sea as I dove into the water, and which had drifted right up to the ladder.

The crew filmed the rescue and Glen will upload it to YouTube, but the insurance and salvage people have our only copy at the moment.

Post-Rescue
The ten-person crew on the freighter, Forum Pacific, was comprised of a Fijian master, Tonga 1st mate, Fijian 2nd mate, Fijian boatswain, and the rest were from Sri Lanka. They were not only competent in rescuing us but wonderful people, too. They gave us clothes, tended to our wounds, fed us well, staged a kava drinking party for us, and were at our beck and call as if we were on a cruise ship. The 2nd mate, a youngish fellow, even gave us $560 out of his own pocket and said we did not have to repay him!

The Forum Pacific is 87 meters long, displaces about 30,000 tons, and runs a circuit from Auckland to Tonga to Niue to the Cook Islands then back to Auckland, largely delivering aviation fuel in large canisters, vehicles and containers. Lucky for us they were in route between Tonga and Niue at the time of our capsize and did not have to divert far out of the way to rescue us. There was some delay, though, and the people of Niue were eagerly awaiting the ship when she arrived, especially because there was a toilet paper shortage on the island.

The Forum Pacific previously sailed in the Indian Ocean and was captured by Somali pirates and the crew held for ransom for six months. Only one of the present crew, the Sri Lankan electrician, had been held hostage. He said, except for the initial attack with RPGs, the Somalis were nice. The ransom paid he said was $1.8 million.

On arrival at Niue the New Zealand High Commission took over and began processing Glen and contacted the US Embassy to start getting me a replacement passport. I emailed my insurance agency and arranged for a wire transfer of funds. We were sort of local celebrities and had to repeat this story umpteen times to all the yachties.

Niue has only one flight per week, and it is to and from Auckland, and we were able to get tickets and returned to NZ after about five days. Glen flew on to Christchurch on the South Island to visit family while I have been busy here in Auckland with the US Consulate General, insurance, and a potential salvager, who coincidentally owns the Forum Pacific.

Final Thoughts
Glen and I were unlucky that such an intense wind hit us, but on the other had were very fortunate that things fell into place for a quick rescue. Having the EPIRB that sent out our GPS position was key to that, as was the competency of New Zealand’s Rescue Coordination Committee who sent an aircraft to find us 1400 nm away! Lucky were we too that the Forum Pacific was nearby and that she had a competent crew. And we were also lucky we had not secured the dinghy to the aft deck as we sometimes do for a long passage, but had instead just set her down on her chocks which allowed her to float out and provide me with shelter.

The EPIRB incidentally continued to transmit for four days. Anna moved at a leisurely half knot to the NW, and is still afloat awaiting salvage.

I never thought I was going to die. As soon as I hit the water after the capsize I obviously realized that my chances for an early departure were suddenly greatly increased and that I must focus on surviving, but I never for a second felt the fear of death. Some of that comes from many disaster experiences (set out below), and the knowledge that catamarans do not sink. A couple of days after rescue, though, about four in the morning as I lay in bed in Niue, I thought how damn close Glen and I had come, and chills swept over me.

People here in NZ are telling us that Anna is the largest cruising (that is, non-racing) catamaran ever to capsize.
I have now had the following disaster experiences at sea:

• Was on a catamaran that sunk to deck level due to a maintenance oversight in False Bay, South Africa, 2001, and was rescued by the SA Navy.
• Was on a catamaran (the same as above) that was breaking up and the hulls separating from the bridgedeck, on a voyage planned to be from South Africa to Portugal, about 2007, and we barely made it into port in Namibia.
• Was alone on a motorcat in Labrador that lost both engines and was floating among icebergs and was rescued by local fishermen.
• Was on a catamaran that lost both headstays.
• Was on a catamaran that ripped its jib.
• Was knocked overboard by the boom in an accidental jibe.
• Was on a catamaran that had a trampoline track torn away.
• Was on a catamaran that had three stanchions knocked over when deploying a sea anchor.
• Was on a catamaran that lost its hydraulic steering.
• Was on a catamaran that lost its cable steering.
• Was on a catamaran on which a radial drive (quadrant) came loose from the rudder post.
• And now, was on the largest known cruising catamaran to capsize, saved by NZ rescue aircraft and a passing freighter.

I don’t blame anyone who is reluctant to go sailing with me.

Finally, I often tend to be cynical and fear that people are getting worse, more violent and criminal and selfish, but this experience has given me new faith in my fellow human being. Except for one know-it-all yachtie from California, we found everyone empathetic and generous.

See the video of the rescue;  

This is actually serious subject matter but you wouldn’t be able to read it all without some relief, hence the illustrations, forgive me.

My thoughts, here goes;

1  ) “Chris White” shows up prominently in the title and every commentary I have seen.  This smells of fallen celebrity syndrome.  The fellow has been idolized up until now, his name an automatic endorsement for a vessel, whether it’s appropriate for its owner or not.  Subtly singling him out for a bashing may satisfy some chicken-inspired pecking hierarchy instinct but it is not really appropriate and rather sneaky.  The vessel is what it is, an intentionally (expensively) very lightweight, heavily canvassed, performance first vessel that also has some cruising amenities.

Chris White’s unfortunate commentary on his own website declaring the vessel’s suitability for management single handed or by a cruising couple appears to be the only egg on his face I can see.  See Chris White on the Atlantic 57 at http://www.chriswhitedesigns.com/atlantic_cats/a57/

His qualifier suggesting that a typical couple can easily learn to safely do the necessary sailing procedures properly and in sequence on these vessels is a dodge as far as I am concerned.  But, if you are a potential buyer who chooses to believe that, you probably won’t listen to anyone anyway so he may as well say whatever he wants to.

Emphasizing sailing speed before all other considerations appeals to the imagination of many buyers.  There is considerable pressure to emulate racing vessel performance in cruising designs and terrific marketing pressure to go oversize (higher builder’s margins).

Note the catamaran eggs

The consequent marketing coercion to think that bigger and faster translates to safer, more comfortable and easier to live with, or just plain better, goes largely unchallenged.  I would like to think that some reconsideration of the rationale delivered to potential and trusting owners would be engendered by this incident.

The two guys that survived this story were apparently fit and experienced but lost everything in a matter of seconds.  Are you an expert offshore sailor with impeccable weather judgement? Is your wife?  Is anyone?  I don’t imagine for a moment I would be generally better at things than the protagonists.  There is always a human element.

What risks are you prepared to take?  How close to the edge do you like to live?  How long are you willing to (or can you) endure hardships and high levels of vigilance?

Select your craft accordingly.  If, having done your homework, you decide on a Chris White Atlantic 57 and it capsizes who’s to blame?   It looked nice and provided the thrills.

Chris White says this 57 is a 55 with 2’ added at the bow so presumably both vessels have the same beam but the 57 can carry more sail with the crossbeam moved ahead.  Having undertaken similar design studies myself, I would speculate that the extra two feet consist of a refinement of the cutwaters with fairing into the original 55’ lines?  This alteration would do very little to increase bow buoyancy while adding a structural weight burden.  There is also usually a proportional loss of expanding volume above the waterline to resist planting the bows.  The resultant sharper bows look consistent with ultimate performance boat trends and have an automatic visual appeal but at some cost to seaworthiness.

Although some stability threshold was perhaps crossed, the factors contributing to the capsize incident should rightly be attributed to the combination of vessel, crew, and expectations. Chris White can only be blamed for giving people what they think they want and careless marketing has reinforced the idea that what he wants for himself is good for everyone.

It is anticipated that boats like Hydroptere will eventually capsize; no surprise and even some satisfaction that the envelope was pressed, but when the Atlantic 57 turns over while a number of like designs are marketed as a cruising couple’s package, with a fawning and gushing marine press approving of every extreme, what are people thinking?  What did they expect?  Thanks to the Atlantic 57 incident, the boundaries of the cruising safety envelope have been demonstrated, fortunately with no loss of life.

Hydroptere - right side up

Hydroptere - Upside down

We need to recognize that Chris White unabashedly operates at an extreme end of the market spectrum and hold appropriate expectations for his vessels.

I am never going to get written up as a designer of cutting edge performance vessels (I hope) but we continue to believe that a cruising vessel should be able to take care of itself to the greatest practical degree as you never know what may occur.  There are no guarantees but we are obliged to work toward that end, non-thrilling as it may be, and hope for quiet success.

2 ) The non-openable escape hatches are a real alarm bell in this story, everything else has shaken out predictably.   It would be interesting to know what hatch design the Atlantic 57 had installed.  The air pockets that form in the hulls (and keep the floating “altitude” reasonable) may have put the hatches under enough pressure to hold them shut, but only if they opened inward which seems rather unlikely. Bashing them with a hammer, a fire extinguisher and a grappling hook?  Huh? Some kind of a mystery.

Outside view of typical approved hatch

I have heard from a mole in the cat cruising fraternity that often the escape hatch openings get glassed over to solve leaking hatch issues.  That is demonstrative of a bizarre sense of values.  The Antares 44 design uses costly Goiot hatches configured for the job and approved by the ISO for the offshore application.  They open from both sides and have a self-releasing locking bar if inverted.  I have not heard that they have any endemic leaking issues.  I hope the hatch cost is money well spent, but only as insurance.  (Though it is very enjoyable to open them when anchored in a pleasant spot.)

As an aside;

The placement of the escape hatches is something to consider as the higher they are in the hull when upright the lower they are when inverted.  This could help with maintaining the air pockets.  The survivor of the 1995 Catana loss in the Med (follow link: http://www.timesonline.co.uk/tol/news/uk/article7111417.ece?token=null&offset=0&page=1) reported a lot of “blowing” going on when the vessel was inverted and the outrush of air that occurred when the hatch was opened settled the vessel deeper in just minutes.  Our hatches lead out onto the bridge deck and are about as high (upright) as they can be.  I tried to make them as practical as possible, considering the physics and the ergonomics.  I don’t think they should be dismissed as just some annoying CE approval requirement and largely ignored as a design element.  We should all do the best we can and encourage their regular inspection and maintenance.

The video of the Atlantic57 rescue illustrates the issues rather too well.  The vessel is floating down by the stern to a degree that puts the hatches periodically awash.  I would presume that figuring the hydrostatics for inverted and uncontrollably flooded compartments would be a futile exercise so without a test, we can only hope for a better situation.  A vessel like the Antares 44 has transom locker compartments unoccupied by saildrives etc. that we might anticipate would help hold her ass up in similar circumstances, but I don’t know for sure and would rather not find out.

In order to maintain the hull air pockets, it would be a reasonable procedure to try to close the bilge pump discharge and sink drain sea cocks if possible to keep compartments from venting and consequently flooding.

3 ) The difficulties inherent in swimming around the inverted 57’ vessel sound a little understated in the account. We have equipped boats with padeyes on the bridge deck which are probably a good idea if you think you may be testing the envelope but rigging some temporary jacklines to pass under the bridge deck when offshore might be more practical and you could configure them to accord with the specifics of your particular vessel and your inverted swimming imagination.  It sounds like the Atlantic 57 has exposed steering cables under the bridge deck, a configuration I don’t know the details of.  They seem to have had an unexpected second function in the play of events.

4 ) The fellow inside reported his disorientation with the vessel interior upside down.  I find this interesting as it seems to be surprisingly difficult to conceive of the complicated interior spaces upside down.  I can cheat by inverting the view of the computer model but perhaps as an owner all one can do is perform handstands to pass the long hours of a solitary watch.

5 ) The dinghy must have been very lightly secured to bob along right way up after the vessel inverted, hard to figure the dynamics of that one and I wouldn’t want to rely on it happening again.  We encourage owners to tie the rigid inflatable securely to the davit structures to prevent the swaying and bouncing which can generate high dynamic loads.  I have no doubt our dinghies would keep company with the vessel; another interesting exercise of the imagination.

6 ) The rescue video is frightening for reasons outside the inverted cat issues.  I wonder why the lads didn’t just get in the dinghy and make their way over to the rescue ship?  The first man’s choosing to dive in and swim for it in rough seas with no buoyancy aid of any kind appears to have been a rash decision.  The second fellow came so close to being mashed between the rescue ship and the inverted cat’s rudder while the two vessels ground against each other that I would say that was his moment of greatest danger.  The ship was there and made the rescue, all credit to them, but what a finale to a series of near misses with tragedy.

7 ) Kelly Wright provides a list of his unfortunate experiences at sea.  I noticed how prominently steering gear failures figure therein.  It gratifies me that we use shaft and gearbox steering and would not likely make cause to grace his list.  On the down side; we don’t use any steering cables inside or outside the vessel however so they will never be there as substitute lifelines.

8 ) The claim to fame that “The Atlantic 57 is the largest cruising catamaran to have capsized” assumes that it may indisputably be categorized as a cruising boat.   The Atlantic 57 has amply demonstrated that it is not a cruising vessel for the vast majority of owners and certainly none that I have had contact with.  At this size, it looks like you really need crew.  Would they be cruising too or just working the passage?

9 ) Mr. McConchie and Mr. Wright should be recognized as having done a remarkable job of dealing with very challenging circumstances.  Anyone inclined to second guess their decisions ought to remember the adage, “There but for the grace of god go I”.  The presence of mind exhibited, especially by Glen on the inside, is an example of levelheadedness that we may all hope to exhibit should such circumstances occur in our own experience.

How many times have we identified with the surge of despair reported by the survivors huddled in a liferaft as they watch their monohull sailboat slip beneath the waves, dragged inexorably down by its ballast keel; the tiny liferaft with all its limitations becoming the sole patch of survival territory in a sea stretching to the horizon in all directions.  It is interesting to note the nature of the discourse when multihull sailors contemplate similar disastrous circumstances, a discussion of challenges, procedures and possibilities to adapt and make do with the floating platforms loaded with potential resources.  As one owner recently commented, “If there is an inch of boat showing, I’m staying with it.” All vessels may be overcome by disastrous events but how encouraging it must be for survivors of cat inversions to have a platform of hope beneath them, how much better still when the escape hatches actually open.

TC