why don't sailboats have wheelhouses/cabins?

[thaikarl]

i'm new to sailing. i've been crew on my friends 50' ketch that has a wheelhouse built over the cockpit. it sure is nice to get out of the wind and rain and sun! we can open the doors and get in and out to the deck quite easily, and the sides of the wheelhouse open up to handle sheets for jibs and access to job winches. but, i notice that most keel sailboats have canvas dodgers. some of them are quite elaborate. but they look rather "tacked-on" and the plastic windows are hardly as clear as glass.

why don't sailboats have built-in wheelhouses or cabins? i'm sure they would be a liability in a typhoon, but not many of them are EVER going to be in that kind of weather.

http://picasaweb.google.com/thaikarl/MikesBoat?feat=directlink

[TeddyDiver]

There are quite a few actually. Cruising catamarans have, most mono's considered as "motorsailors" have kind of a wheelhouse. Puristic or traditional view of a sailboat doesn't look them good becouse they are considered more as a handicap than an asset.

[sloopjb]

I thought it was "to get to the other tide"

[PAR]

Anything sticking up through the deck is a hindrance to sailing performance. Some things you just have to live with, others not so much. If the parameters of the design suggest relaxing at a berth, dock or hook as the major priority, then the boat can have a huge set of deck structures. On the other hand, if the boat is expected to move well by wind propulsion alone, you need to optimize it's abilities with as clean a boat as possible, so deck structures are minimized.

[Hägar]

Here in the North many have a wheelhouse. But of course with the restrictions PAR mentioned.

[Brent Swain]

Anything sticking up through the deck is a hindrance to sailing performance. Some things you just have to live with, others not so much. If the parameters of the design suggest relaxing at a berth, dock or hook as the major priority, then the boat can have a huge set of deck structures. On the other hand, if the boat is expected to move well by wind propulsion alone, you need to optimize it's abilities with as clean a boat as possible, so deck structures are minimized.


I've often seen far more windage in a crew sitting in an open cockpit than one would get with a small wheelhouse. Their centre of gravity may also be lower in a low wheelhouse. The extra stowage for heavy gear under the wheelhouse floor more than compensates for the weight of the wheelhouse. The buoyancy in the wheelhouse drasticaly improves the boats ultimate stability.
Almost all of my boats have a small wheelhouse.
Why aren't they more common. It is, I believe, the left over cultural residue of that 300 year old form of mental illness called "puritanism" , defined as the terrible , nagging fear that someone , somewhere , just might be having a good time.
As I point out in my book, leaving the helmsman as exposed to the elements as an open cockpit only steering position does, is simply bad seamanship.
Would you buy a pickup truck which can only be steered from the open box?
One can drive a car for long hours and be only marginaly tired, but a couple of hours in an open cockpit in bad weather can leave one exhuasted, a dangerous situation when it come to decision making. There is no reason that sailing a boat should be any less comfortable that driving a car , or a pickup truck; from the proper steering position.
Outside only steering positions are a throwback to the days when people went to sea against their will. Even latter day clipper ships provided some protection for the helmsman..
Many people have been severely injured or washed out to sea from an open cockpit. I've never heard of anyone being washed out of a wheelhouse.
Injuries of someone in a wheelhouse are extremely rare.
Dodgers? Comparing a dodger to a wheelhouse is like comparing a hotel room to a lean to. Dodgers are the low end of the learning curve. Their owners ,as they get older and wiser, slowly graduate to a solid dodger, then to a wheelhouse, wishing they had jumped to the logical conclusion in step one.
My wheelhouses are of welded steel construction, so strength is a non issue.
I believe it is possible to build wheelhouses out of any modern material which are strong enough to make structural failure extremely unlikely, far less likely than loss of life or injury due to lack of a wheelhouse. Just skip the picture windows, which you wouldn't have anyway, without the wheelhouse.
I love cruising year round in BC, with the wheelhouse making time of year irrelevant. I love to stick my head out in a driving snow storm , wearing only a T shirt , to wave at the lucky guy in the half million dollar "Trendy" boat , who is freezing his ass off in an open cockpit.
If I convert him to the wisdom of a wheelhouse , I will save him a lot of misery, and possibly save his life.
Boats of my design ,which have been built without the wheelhouse I design in them are called " The Hypothermia Version"
Brent

[bntii]

Even dodgers can make sailing here on the Chesapeake unbearably hot.

A wheel house- forget it.

[PAR]

Brent, I don't know what kind of crew activities you have in open cockpits that rival the windage of a wheelhouse, but maybe next time you can tell the to sit down. So how exactly is the lump in the bilge going to offset the extra windage of a wheelhouse? Extra stability, please. If you're in conditions where you're grateful because the wheelhouse offers some extra stability, then you'll likely not have a wheelhouse when the time comes. I know, I've been there and watched them shear their mounting bolts and shift sideways with boards seas.

Simply put, people who need wheelhouses on their sailing yachts, don't want sailing yachts. The vast majority of folks that want sailing yachts, actually want to get to windward.

Wheelhouses are typical of inclement weather cruisers. Those that putter around in northern latitudes and have cabin heaters billowing clouds of smoke. Unless you have the ability to crank up A/C while underway or on the hook, a wheelhouse in temperate climates is a cooker, that drives all but Satan himself out into the cockpit.

It's true as you get older the less you enjoy a healthy slosh to windward, preferring to lounge in a wheelhouse with a cup of coffee and the latest copy of SAIL magazine. I'm fairly convinced this isn't cruising. I can look at pretty post cards of distant shores, sip coffee in the comfort of my family room and get the same effect with a lot less effort.

In the end, some need wheelhouses, but in smaller sizes have to sacrifice quite a bit to have one. In mid size yachts it's a bit of a contrivance, though if cleverly designed can be handy, though still eating substantially into the performance envelope. In larger yachts you might as well have one. They are nice if the boat can wear one without seriously detracting from performance, which is why we try to convince the wind to propel us in the first place, other wise we'd have a poweryacht.

[TeddyDiver]

It's easy to condem wheelhouses in Florida, but anyone sailing more than avarage preciate it's advantages in the north.. Sometimes it's a necessity if you want to sail at all..

[TollyWally]

Nothing better than a snug wheelhouse, a well burning stove, and a hot mug of your favorite choice in northern climes..

[PAR]

I don't think it's location as much as vessel size. The factors are simply windage and comfort. Small and mid size yachts pay a windage penalty and also usually can't afford the climate control necessary, inside the wheelhouse.

I grew up on the eastern shore of the Chesapeake, where the summers got hot and sticky and the winters wet, cold with occasional snow. Sure, for a few months out of the year it was nice enough to head out, enclosed in a boat mounted sweat box, but summers would drive you out into the fresh air and winters would require a pot belly.

As you get older, it's not the ability you lack, but the willingness to tolerate less comfortable environments. This is where climate control comes in and you need a fairly big boat to carry this off, without excessive windage or strain on system capacities.

[bntii]

I might be worth noting that in these parts cockpit enclosures are common for vessels used off season. These are fully convertible canvas structures comprised of joined dodgers and biminis with removable side curtains. If well designed and constructed, they are wind and rainproof. Stripped of the sides and having the dodger folded down there remains the only thing really essential for survival around here- a bimini and FULL flow of air through the cockpit.
They seem a reasonable solutions for sailing in the couple of months in these parts that require their protection. I am with Par on this one- if the vessel is large enough have both... I sailed a beautiful Alden motor sailor for a time which had a enclosed midships house in addition to a aft helm. Perfect- the best of both worlds. It suited the 63' hull fine.

Different horses for different courses eh Brent? We don't all live in the pacific northwest..

[Brent Swain]

There is less windage in my wheelhouse than there is in three people sitting in the cockpit. Their centre of gravity is lower, and closer to amidships when they are in the wheelhouse.
With all my haches open , in hot weather , it is cooler in the wheelhouse than it is in the cockpit , or on deck, and the UV is near zero. The chances of my welded , small wheelhouse ever being ripped off is far closer to zero that that of any trunk cabin on a plastic boat.
Without the space under my wheelhouse floor, heavier gear would be stowed much higher, offsetting any weight savings lack of a wheelhouse would offer. Then there is the bad seamanship of leaving the helmsman exposed to weather , hypothermia and the threat of being hit by waves and injured or washed overboard.
In areas where pirates could be a threat, I can sit in my wheelhouse and see if anyone is on deck, and take out his testicles with my speargun, thru a port or vent , without having to stick my head out first.
Brent

[bntii]

Do you have a picture of the house you are describing by chance Brent?

Thanks much

[Brent Swain]

Brent, I don't know what kind of crew activities you have in open cockpits that rival the windage of a wheelhouse, but maybe next time you can tell the to sit down. So how exactly is the lump in the bilge going to offset the extra windage of a wheelhouse? Extra stability, please. If you're in conditions where you're grateful because the wheelhouse offers some extra stability, then you'll likely not have a wheelhouse when the time comes. I know, I've been there and watched them shear their mounting bolts and shift sideways with boards seas.

Simply put, people who need wheelhouses on their sailing yachts, don't want sailing yachts. The vast majority of folks that want sailing yachts, actually want to get to windward.

Wheelhouses are typical of inclement weather cruisers. Those that putter around in northern latitudes and have cabin heaters billowing clouds of smoke. Unless you have the ability to crank up A/C while underway or on the hook, a wheelhouse in temperate climates is a cooker, that drives all but Satan himself out into the cockpit.

It's true as you get older the less you enjoy a healthy slosh to windward, preferring to lounge in a wheelhouse with a cup of coffee and the latest copy of SAIL magazine. I'm fairly convinced this isn't cruising. I can look at pretty post cards of distant shores, sip coffee in the comfort of my family room and get the same effect with a lot less effort.

In the end, some need wheelhouses, but in smaller sizes have to sacrifice quite a bit to have one. In mid size yachts it's a bit of a contrivance, though if cleverly designed can be handy, though still eating substantially into the performance envelope. In larger yachts you might as well have one. They are nice if the boat can wear one without seriously detracting from performance, which is why we try to convince the wind to propel us in the first place, other wise we'd have a poweryacht.


I guess we could also do it your way, stand on a bouncing dock in driving rain and a full gale, looking at pretty pictures, while tearing up $100 bills. Same effect. Sounds like fun!
I prefer to do my macho in the ring. Cruising is about pleasure, and there is little pleasure for us non misery seekers from sitting in an open cockpit in bad weather , or being forced to stay ashore , waiting for those few days a year when one can be comfortable in an open cockpit.
Your misery seeking masochism has turned far to many people off cruising , especially women, yet misery seekers still can't understand why so many women have been turned off cruising for life. Duhh!!!
My wheelhouses are 10 to 14 inches above the top of the trunk cabin, offering little windage. I'll post pictures when the opportunity arises.
I always get a laugh out of people who avoid wheelhouses over windage issues, then put a dodger up that is never taken down, and put lee cloths all around the cockpit. With a good, compact wheelhouse, these become redundant , with a huge reduction in windage
Brent

[souljour2000]

I think there were simply some strong opinions made here...and largely valid points from both sides..it's too bad this thread got so froggy...

[tom28571]

Perhaps if your sailing is mostly cruising for long distances (not day sailing), a permanent protected enclosure is a welcome thing to have. I know that doing a winter delivery in cold and wet weather in an open cockpit is the pits (pun intended). On the other hand when I sail on a boat in decent weather with even a bimini such that I can't see all of the sails, that is the pits also. that is the point of sailing. Otherwise I'd rather be on a powerboat. Some like to be out in the elements and some don't. Some actually like to be on a monohull that heels in the wind and some like the palatial ballroom of a covered and level catamaran.

Arguments with those that are committed to either are useless. For daysails, even in bad weather, I'd rather be out there. Maybe that is because it feels so good after we get warm and dry when its over:D

[Brent Swain]

Thats why I like to keep a wheelhouse low enough to see over while sitting in the cockpit. Gives me both options ,for any kind of weather.
Brent

[tom28571]

Thats why I like to keep a wheelhouse low enough to see over while sitting in the cockpit. Gives me both options ,for any kind of weather.
Brent

How does that work? Do you have dual steering stations? How big does a boat have to be to make that practical?

[Brent Swain]

Outside, I steer with the tiller . Inside, I steer with a jog stick or auto helm ,hooked up to the trim tab on the trailing edge of the rudder. That makes throwing the rudder hard over in a following sea a one finger operation . A six year old could steer from inside in a big quartering sea.
It's practical in any sized boat, even my 26 footer.
The Argus transport planes are totally controlled by trimtabs.
Brent

[jalmberg]

i'm new to sailing. i've been crew on my friends 50' ketch that has a wheelhouse built over the cockpit. it sure is nice to get out of the wind and rain and sun! we can open the doors and get in and out to the deck quite easily, and the sides of the wheelhouse open up to handle sheets for jibs and access to job winches. but, i notice that most keel sailboats have canvas dodgers. some of them are quite elaborate. but they look rather "tacked-on" and the plastic windows are hardly as clear as glass.

why don't sailboats have built-in wheelhouses or cabins? i'm sure they would be a liability in a typhoon, but not many of them are EVER going to be in that kind of weather.

http://picasaweb.google.com/thaikarl/MikesBoat?feat=directlink

Simple. You can't see the sails if you're under a roof. Even dodgers drive me crazy for that reason. Or are you talking about motoring?

-- John

[Omeron]

Brent, i am intrigued by your statement that the buoyancy in the wheelhouse drastically improves the boats ultimate stability. For the wheelhouse's buoyancy to contribute anything to the stability it must be immersed in water, meaning simply, the boat has inverted! and possibly sinking. A few degrees before that happens,the mass of wheelhouse is actually helping the hull roll further.
In a moment like that i would be rather out on an open deck, than the likelyhood of getting trapped in a wheelhouse.

[apex1]

Brent, i am intrigued by your statement that the buoyancy in the wheelhouse drastically improves the boats ultimate stability.

Nevertheless its true!

[ancient kayaker]

This is one of those "horses for courses" thread where nobody wins or is converted, but interesting nevertheless. Having tried to put a small sail on a kayak, I can vouch for the windage effect of the crew, in some circumstances anyway, even sitting down!

[Crag Cay]

Nevertheless its true!
The large tall deckhouse is how the RNLI boats generate their AVS of virtually 180 degrees.

The Moody 45DS also includes deckhouse volume in their ultimate stability calculations, but there does seem to be a variation in the way the access door onto the aft deck has been executed in the above examples, especially as both are deemed to ultimately do the same function.

[jalmberg]

The large tall deckhouse is how the RNLI boats generate their AVS of virtually 180 degrees.

The Moody 45DS also includes deckhouse volume in their ultimate stability calculations, but there does seem to be a variation in the way the access door onto the aft deck has been executed in the above examples, especially as both are deemed to ultimately do the same function.

Sorry, but you couldn't give me one of those Moodys... check out this video:

http://www.youtube.com/watch?v=0yUaQ0sxpTI

The boat needs 2 wheels because the only way to see where you're going is to lean overboard. Totally absurd... It's a power boat with an auxiliary sail.

-- John

[Luckless]

Simple. You can't see the sails if you're under a roof. Even dodgers drive me crazy for that reason. Or are you talking about motoring?

-- John

Skylights?

[jalmberg]

Skylights?

I think a previous poster got it right... the word 'sailing' means different things to different people, so there are at least two different conversations going on here.

I actually think Brent's low-profile 'deck houses' are totally reasonable compared to that summer cottage on the deck of the Moody.

-- John

[MikeJohns]

This is interesting as I have added low profile pilothouses to vessels before and the stability change is not always so obvious.

Interestingly counter-intuitively a flooding cockpit can actually boost the righting moment over part of the GZ curve (although not inverted) it depends on how the vessel trims longitudinally and sometimes a flooding cockpit actually keeps the more bouyant aft sections in play.

But the GZ curves are very misleading, the propensity of a small vessel to invert in a violent knockdown depends more on the reserve area under the GZ curve past 90 degrees and very little on the curve from 0 to 90. In this regard even a small pilothouse can be quite beneficial.
If the Pilothouse remains intact and the doors are shut it has a significant effect from around 70 degrees heel to 180, but damaged stability goes down ( think of it full of water) . For most of us immersing the sides of the house is enough to save the boat in the first instance.

[capt vimes]

in my opinion it is definitely not a mistake to have a shelterted place from where you still can steer your yacht - within limitations of course...
especially if you are taking this ship on an extended cruise....
i have been too often standing at the helm during night in snow, rain and thunderstorms where i only had to keep the course - one could do from a sheltered place as well...

if the wind- and seaconditions are stable i would very much prefer a small pilothouse from where i can control the course and check the instruments and be well out of the weather...

but one thing must be made clear as well:
if the conditions are bad, the only place to be is the helm in an open cockpit..

why?
one need to be able to see what the sails are doing and where and how the seas are coming from, react quickly and have the lines of your sails at hand and this is something absolutely impossible to do from a pilot- or wheelhouse!

my next yacht will definitely have a pilothouse and the possibility to steer from there, but my place will be most of the time in the open because you cannot sail a yacht from an enclosed place - get the ship in stable conditions from A to B even under sails... that you can do from the pilothouse, but this is nothing i refer to as 'sailing'...

some designs i have put on my list....
http://www.german-yachtbau.de/German-Series/german-48-series/german48PH/german48PH_Risse.html
http://www.atlanticyachts.nl/nieuwjacht.php?color=0C795A&newyacht=Atlantic%2048hk
http://www.stadtdesign.com/images/products/429_int.jpg

[gonzo]

I don't understand how putting a wheelhouse-extra weight- over seated people lowers the center of gravity. If the crew caused more windage, race boats would all have wheelhouses. There are no restrictions in the rules about it. Actually it is the opposite, openings have restrictions for ocean racing.

[Eric Sponberg]

I'm with Brent and the original poster here. Pilot houses or wheel houses are really nice to have on an ocean voyaging sailboat, or any boat that goes out in either really hot or really cold weather. When you are day-sailing or just putzing around, planning to be back to shore soon (like, within a couple of days or a week) you do nicely without. But for offshore voyaging, pilot houses are VERY desirable (he said, speaking from thousands of miles of experience WITHOUT a pilot house.) I wrote an article for SAIL magazine on just this topic back in March, 1981--my very first SAIL article, actually, I have it around here somewhere. It covers basically all the points about comfort, weight, CG, that have already been pointed out so far in this thread.

My Globetrotters all sport pilot houses with inside steering. I have found that below about 40' Loa, it is really hard to make a pilot house work, particularly if you also want an aft cabin as well. Although, I have seen some nice arrangements in a Vancouver 32 and an Islander 36. My Globetrotter 45 has a nice split pilot house where the back end is open to the cockpit, and the forward end has the inside helm and nav station. Going up in boat size from here really opens up the possibilities. On my current design, a Globetrotter 66, we have the main saloon, the galley, and the nav station with inside helm in the pilot house, which actually is more like a sort of high deck house. Longer boat length allows more length and width in the pilot house.

Count me in on the yes side on this one.

Eric

[Chuck Losness]

Count me in on the yes vote here too. A friend has a Shannon pilot house 38 and I helped him deliver it from La Paz to San Francisco. It was great. Never had to put on foul weather gear, never got wet and rarely had to even get out of my slippers. In hot weather we just opened the windows in the pilothouse and closed them when it was cold. But the best part was that you had a comfortable chair/seat facing forward to sit and keep track of where you were going instead of looking where you have been as is the case in you typical sailboat when you are hiding behind your typical dodger. They don't call them a dodger without good reason. I sure wish my Gulfstar 37 had a comfortable wheelhouse. I also wish my gulfstar had a cat ketch rig for ease of sailing but that's probably not possible. I might talk to eric about it one of these days.

[TollyWally]

I fished a Skookum 54, which is a motorsailing boat first designed for an aborted Midway tuna fishery in the late 70's. While the Midway thing didn't pan out they are splendid boats in their own way. Skookum didn't quite get sailboat rigging I don't think but these were solid boats built of fine materials. Ended up being splendid boats for pirate halibut fishing in the middle of the Gulf of Alaska before it went IFQ. (Not us LOL)

[Brent Swain]

I don't understand how putting a wheelhouse-extra weight- over seated people lowers the center of gravity. If the crew caused more windage, race boats would all have wheelhouses. There are no restrictions in the rules about it. Actually it is the opposite, openings have restrictions for ocean racing.


People seated in a low wheelhouse are seated lower than the same people seated in a cockpit. The extra stowage of gear below a wheelhouse floor more than offets the weight of the wheelhouse.
Calculate the number of square ft of windage on a crew in an open cockpit, then calculate the windage on a 12 inch high wheelhouse. Simple math. Excuses for the lack of wheelhouses on sailboats are based on myth, which have gone unchallenged for too long, and wont stand up to open debate.
In a knockdown , if you are in a wheelhouse you stay in the boat, in an open cockpit you are overboard.I know where I'd rather be.
When was the last time you heard of anyone being washed out of a wheelhouse, or suffering hypothermia in one? In open cockpits it is common.
Racing masochists, in rough water, are up to their necks in cold water , being jacuzzied along the decks, while cruisers are warm and dry in their comfortable wheelhouses. So why would anyone take racing as the guide for intelligent cruising?

[ancient kayaker]

i'm new to sailing. i've been crew on my friends 50' ketch that has a wheelhouse built over the cockpit. it sure is nice to get out of the wind and rain and sun! ... why don't sailboats have built-in wheelhouses or cabins? i'm sure they would be a liability in a typhoon, but not many of them are EVER going to be in that kind of weather.

Makes sense to me, but maybe just not practical on every sailboat.

I don't understand how putting a wheelhouse-extra weight- over seated people lowers the center of gravity ...

Neither do I. I assumed what was meant was, the buoyancy of the wheelhouse assisted self-righting after a knock-down and tended to discourage a total capsize.

People seated in a low wheelhouse are seated lower than the same people seated in a cockpit . The extra stowage of gear below a wheelhouse floor more than offets the weight of the wheelhouse.
Calculate the number of square ft of windage on a crew in an open cockpit, then calculate the windage on a 12 inch high wheelhouse. Simple math. Excuses for the lack of wheelhouses on sailboats are based on myth, which have gone unchallenged for too long, and wont stand up to open debate ...

Hm... a crew of N is going to have less windage than a wheelhouse capable of housing all of them, even if N = 1. If a boat's design allowed crew to function in a wheelhouse only 12" high the a cockpit could be deep enough that only the crew’s heads would be exposed to the wind and only if all of them were looking. If there are many crew on deck in a storm they are working on more than the helm.

However, while I reject your math, I vote for the wheelhouse-equipped boat! I don’t think a wheelhouse needs to be justified by this kind of argument, it is safer and more comfortable.

Racing boats would have them if they went faster with them; can’t argue with that kind of math ...

[Brent Swain]

Racing boats used to have bendy masts because that was the only kind that would work. Then the Kiwis showed up with a stiff mast and kicked everbody's ass.
There was a time when big mains and tiny fore triangles wass the only thing that would work. Then it was tiny mains and big headsails , then it went back the other way. So much for the infallibility of racers logic.

[gonzo]

I can't see how people are going to be seated lower because you build a house over them. They are at the same height, where the cockpit seats would be, but with a structure over them. Ergo, the center of gravity is higher. As for the heavy stuff accumulated under the sole, it would be there anyway. Whether it is desirable or not is a different question, but the claims of lower center of gravity don't make sense. As for the floatation to help on a knockdown, that only works if it is a waterproof wheelhouse. Many are open and would be a hindrance when they flood for the boat to right itself.

[mdcf]

Racing boats used to have bendy masts because that was the only kind that would work. Then the Kiwis showed up with a stiff mast and kicked everbody's ass.
There was a time when big mains and tiny fore triangles wass the only thing that would work. Then it was tiny mains and big headsails , then it went back the other way. So much for the infallibility of racers logic.

It appeared in the last vendee globe that a significant proportion of the boats had something coming close to a wheel house. Of course it would never be called that :)

[capt vimes]

It appeared in the last vendee globe that a significant proportion of the boats had something coming close to a wheel house. Of course it would never be called that :)

you mean the nav-station/pantry/saloon/berth/head&showers thingy of them? :D

[TeddyDiver]

After all it boils down on your preferences - like sailing suits :D

[ancient kayaker]

is the character on the boat mooning us?



afterthought - or worse ...

[masalai]

Cant enlarge the image to check - posting thumbnails as thumbnails should be forbidden:!:

[TeddyDiver]

You absolutely right.. silly me, what was I thinking :D

[TeddyDiver]

And that takes us back to basics... Sailboats shouldn't have only a wheelhouse. They should have a can in the wheelhouse :cool:

[Brent Swain]

Unlike cockpits, wheelhouses don't have to be self draining , so seating in them can be much lower.

[Chickadee]

Here's a video to illustrate the problem...

http://www.youtube.com/watch?v=iA2f17anxjk

Go to 2:35 don't you feel better now ?

Boat size is really the problem here I believe M. Sponberg is right. Below 12-15m the thing is too proeminent for correct upwind performance

[ancient kayaker]

too much sail pressing the forefoot down = wet ride ...

[gonzo]

Wheel houses that are not self bailing have to be closed even in moderately rough weather. In the tropics or summer that can be unbearable unless you have A/C. That means running a generator nonstop

[MikeJohns]

Wheel houses that are not self bailing have to be closed even in moderately rough weather. In the tropics or summer that can be unbearable unless you have A/C. That means running a generator nonstop

IMO it makes no difference whether the companionway decends into the salon or into a wheelhouse, so the normal rules apply depending on the vessel and how you assess the risk.

To windward the fwd windows will be closed but you'd usually leave the companionway door/drop boards open until the conditions get really severe. Even then with dorades and blowers you can still ensure copious quantities of fresh air.
Aft cockpits are more prone to being pooped then mid and even then only when running. Heavy double enders seem to be more prone to this so it's going to depend very much on the situation.


But who wants to sail in the tropics :)

[TollyWally]

Are we still having this debate? I think it's horses for courses. I had a very nice outing here in northern climes this weekend. The stove was burning merrily and the coffee was hot. Had the door slid open to bleed off a little heat during the warmer part of the day, it was nice to slide it closed as the sun set. I've paid my dues in atrocious weather in my youth. I prefer heat and some enclosure vs wool and raingear, but that's just me. I wouldn't impose my values on those with a more rugged and robust outlook, nor would I join them willingly. :)

[Guillermo]

The large tall deckhouse is how the RNLI boats generate their AVS of virtually 180 degrees.

The Moody 45DS also includes deckhouse volume in their ultimate stability calculations, but there does seem to be a variation in the way the access door onto the aft deck has been executed in the above examples, especially as both are deemed to ultimately do the same function.
Crag,
As per the Moody 45DS stability curve it seems the designer has considered the deck saloon as a watertight volume to calculate the KN curves.
Do you know if those sliding doors comply with ISO 12216:2002? I would be amazed if they can be considered as watertightness degree 1 and strong enough to resist an inversion.
Nauticats manufacturer told me some of their models cannot be A categorized because of the sliding doors at the sides of the wheelhouse (too low flooding point then).

Cheers.

[TeddyDiver]

Do you know if those sliding doors comply with ISO 12216:2002? I would be amazed if they can be considered as watertightness degree 1 and strong enough to resist an inversion.
But aren't they only temporary immersed
"3.20.1
degree of watertightness 1
protection against effects of continuous immersion in water
3.20.2
degree of watertightness 2
protection against effects of temporary immersion in water"

so degree 2 should be enough for self rightening vessels? And the following..
-Design pressure 70 kPa on decks (ie hatches), 18kPa on cabin sides (sliding side doors) and 12kPa backside of the cabin (companionways)
-Determination of degree of watertightness (ie waterjet test)

and further.. the standard doesn't describe test for watertightness class 1 so how it could be verified??

[Guillermo]

Thanks Teddy.
Yes, perhaps degree 2 may be considered for a selfrighting boat.
But I have serious doubts about that big and seemingly weak sliding door being able to resist a full inversion. Anyother has more info about this?

Have you found a manufacturer of watertight sliding doors for recreational boats, Teddy? We went on this issue some time ago at the STIX and the Seaworthiness threads

[TeddyDiver]

Have you found a manufacturer of watertight sliding doors for recreational boats
None so far..

[AlexMorozov]

Hi, no watertight sliding door, but the pilothouse available.
49156

[Guillermo]

Hi Alex!
I do not understand what you do mean by: "no watertight sliding door, but the pilothouse available". Could you please clarify?

Do you now of any manufacturer for watertight sliding doors to degree 1 or 2 for the recreational market?

[AlexMorozov]

I suppose that sliding door can not be watertight at all.
The picture of my new concept boat (with pilothouse).

[Doug Lord]

Guillermo, found this: http://www.pointeng.co.uk/marinedivision.asp


From the site:

Watertight sliding doors
Sliding watertight doors for pneumatic or electrical operation are approved by the MCA for Large Commercial, Sailing and Motor Vessels up to 80m load line length and will withstand a 4 metre column of water from both sides. A60 class fire rated and non-rated doors are available. Please call us to discuss your requirements.

[Dryfeet]

Give me protection from the wind and spray anytime all the while I'm enjoying a great view! Good for the Admiral too!

[TeddyDiver]

Sliding watertight doors for pneumatic or electrical operation are approved by the MCA for Large Commercial, Sailing and Motor Vessels up to 80m load line length and will withstand a 4 metre column of water from both sides.[/COLOR][/I]
Unfortunately they are a way over any accepptable weight limit in a recreational boat.. Superyachts might be ok with it..
I'm sure it's possible, anyway for class 2, to make light cabin side doors. Maybe there's not demand enought by the commercial manufacturers..

[Guillermo]

Guillermo, found this: http://www.pointeng.co.uk/marinedivision.asp


From the site:

Watertight sliding doors
Sliding watertight doors for pneumatic or electrical operation are approved by the MCA for Large Commercial, Sailing and Motor Vessels up to 80m load line length and will withstand a 4 metre column of water from both sides. A60 class fire rated and non-rated doors are available. Please call us to discuss your requirements.
Thanks Doug.
There are several other sliding door manufacturers for that kind of boats, too massive to be mounted in a forty footer! As far as I know, for the recreational market there are not even category 2 sliding doors, otherwise the Nauticats would not have the problem they have with the side cabin sliding doors not being accepted as of enough watertightness, obliging them to consider the sill of such doors as the downflooding point.

That's why I'm amazed about Moody 45DS's stability curve. If that door does not comply with watertightness and structural requirements, the deck saloon cannot be considered as a watertight space for stability (KN) calculations, and to market the boat with that curve stating selfrightness would be incorrect.

I have written Moody asking them about this and I'm awaiting an answer. If my doubts are not well founded and they provide a satisfactory explanation, at least I will learn who is the manufacturer of such watertight doors for the recreational market ;)

Dryfeeet:
Do you own a Moody 45DS?

[TeddyDiver]

That's why I'm amazed about Moody 45DS's stability curve. If that door does not comply with watertightness and structural requirements, the deck saloon cannot be considered as a watertight space for stability (KN) calculations, and to market the boat with that curve stating selfrightness would be incorrect.
By the picture looks like the slide door openind only back to cockpit. That way it's possible to have maybe 120deg downflooding angle? and so any watertightness isn't mandatory to A category. In that case does it have sills high enough or is the cockpit open down to sole? However if that's the case it's an accident waiting to happen IMO

ps. I believe it should anyway meet the design pressure 12kPa?

[Doug Lord]

Unfortunately they are a way over any accepptable weight limit in a recreational boat.. Superyachts might be ok with it..
I'm sure it's possible, anyway for class 2, to make light cabin side doors. Maybe there's not demand enought by the commercial manufacturers..
==================
It looked to me like they would have the capability of doing special projects which might include lightweight doors. I just googled "watertight sliding doors" and didn't have time to go thru all of them but I did read about several in detail. This one appeared to have potential.....I wonder how they might respond to a request for a light weight door? Might be feasible in production quantities?
==========
Just found this:

"Podszuck manufacture a complete range of doors, complete with control systems, hardware and equipment. Products include marine fire rated doors, joiner doors, hinged and sliding doors and A60 watertight doors. Doors are manufactured from ; metal and composite lightweight materials. All products meet IMO/SOLAS FTP Code. An ISO 9001 certified company."
http://www.podszuck-gmbh.de/myCMS/index.php

They were listed under Allied Marine Services-Prouducts here: http://www.shipequip.com/products.html

[Guillermo]

By the picture looks like the slide door openind only back to cockpit. That way it's possible to have maybe 120deg downflooding angle? and so any watertightness isn't mandatory to A category. In that case does it have sills high enough or is the cockpit open down to sole? However if that's the case it's an accident waiting to happen IMO

ps. I believe it should anyway meet the design pressure 12kPa?
I do not have the rules now here with me, so cannot check if downflooding over 120º requires no watertightness for A category over that. If you say it, it must be so.

But I'm not wandering if the boat is a Category A one or not. What I'm questioning is the fact of including the deck saloon volumes within the watertight zone to calculate the KN curves. That cannot be done if not all appliances are fully watertight and structurally inversion resistant, as for any other vessel, in my opinion.

Let's say the sliding door is 3,5 x 1,8 mts sized, as it looks like.
Applying a 12 kP pressure all over it, we get a total force of: 3,5 x 1,80 x 12 = 75 kN = 7,65 tonnes-force

Am I right? I doubt that door will resist that force.

More opinions?

[TeddyDiver]

Now have to correct a bit.
Supersructures are consideres as area III (not II as I recalled earlier), and the "parts of Area III protected from the direct impact of sea or slamming waves" like rear areas of the superstucture as area IV. Both in areas II and IV watertightness degree 3 is enough. However the 12 kPa design pressure still stands..

[Dryfeet]

Thanks Doug.

Dryfeeet:
Do you own a Moody 45DS?

No. It's a MaineCat 41.

http://www.mecat.com

[Guillermo]

Just a couple of images to exemplify the very different size and type between the Nauticat 38 side doors (which prevents this boat to reach category A), and the Moody 45DS rear decksaloon door.

I even doubt if the windows of the Moody 45DS wheelhouse qualify for A category....

Could it be the volumes considered in the stability calculations and providing that outstanding stability curve are just the ones of the coachroof only? (asuming it forms a watertight volume)

Moody has not answered my questions about this issue. Anybody out there owning one of these boats who could be of help....?

[BATAAN]

Being an old traditional type of guy and having cruised both Mexico, the Marquesas and the Pacific NW I'd like to weigh in on the P/H question.
All the discussion about efficiency, windage and drag gets vague. Bottom line is everything above the waterline is drag, which is one of several reasons traditional sailing vessels generally have low freeboard, not much cabin and no pilot house. They sail much better that way and in the old days with no engine that was life or death, economically anyway.
A good, strong P/H is not cheap to build. Neither is a Bimini/Dodger combo. I have a good friend who is the local "dodger queen" and builds 10-15 a year, and they are expensive, temporary and pretty necessary here in the Pac NW, so she has job security.
A yacht, with its entirely different design needs, has an engine, usually powerful, and crew that are possibly a little softer around the middle than your old time working sailor. The crew is used to couches and roofs, A/C and heating, so of course pilothouses of various sizes and designs come into the equation, especially if the boat is away from the dock more than a few hours.
On this SPRAY type yawl, the P/H is very small and just big enough for the watchstander who can see most of the horizon from inside. I have personally seen green water out the windows when the boat landed on her side at the bottom of a breaking wave off the Oregon coast and was very glad they were small and laminated glass as they were well underwater at the time.
A P/H, unless very strong with small windows, is subject to destruction in a broach, knockdown or breaking wave, opening the vessel to flooding.
Years ago, when working on the 1840s whaling ship CHARLES MORGAN at Mystic Seaport, the absolute ignorance of most of the public about sailing ships was really brought home to me by how many guests asked why "the steering wheel is at the back and you can't see where you're going?".... I would try to explain that seeing the sails is essential, watching for traffic lights isn't as you have a lookout for that. The same applies to pilot houses and biminis. If you must be an inside sailor due to local conditions, keep it very small and strong and put a window in the roof and you will have a wonderful time.
If your sailing is dockside, or summer afternoons, a glass-enclosed condominium on deck makes perfect sense to keep your guests comfortable as you'll probably be motoring to windward with the sail covers on anyway.

[Guillermo]

Here the answer from Hanse Yachts:

"Betreff: RE: Hanseyachts Website Contact

The stability curve for the M45DS is rather impressive. We questioned this in detail with Dixon Yacht Design when the model was first created and the data was submitted for CE approval.

The superstructure/deckhouse volume is included in the stability calculation, this is in accordance with the CE guidelines. As with a more conventional superstructure this calculation assumes that the cabin does not flood significantly during a knock down. In order to achieve this the hatches and doors need to be sufficiently weather tight to prevent a sudden inflow of water. This is the case with the patio door, which is more closely sealed than a conventional sliding hatch garage.

Dixon Yacht Design also calculated that the opening part of the door itself does not immerse until almost complete inversion, so the risk of partial flooding is further reduced. The enormous self righting force also means that the yacht will come upright in a much shorter time period than a conventional type.

To pre-empt a further question:

The superstructure windows and door are all constructed for Moody by a specialist marine supplier from toughened glass. The glass strength/thickness significantly exceeds the structural requirements.

Best regards"


Well, I am amazed to learn that big sliding door is able to resist a 12 kP/m2 pressure all over it, as required by the ISO 12216. As said this may mean a total load of about 7+ tonnes over it.

Even accepting what is said about the watertightness of the deck saloon windows and sliding door, I cannot less than feel quite worried about the structural resistance of the whole of the thing to resist a full knockdown caused by the impact of a wave.

[TeddyDiver]

Well, I am amazed to learn that big sliding door is able to resist a 12 kP/m2 pressure all over it, as required by the ISO 12216. As said this may mean a total load of about 7+ tonnes over it.
Thanks Guillermo of interesting info. And thanks to Hanse yachts too. They don't state excactly the amount of strength achieved. The designer may have had their own calculations (of the forces involved) and they maybe have this way gone around the general 12kPa/m2 pressure requirement??