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J. Dillon
12-20-1999, 09:21 AM
In noticing the cruise ships I see on TV adds. I cannot help think how ugly they are for my taste but more important they look unsafe and top heavy. Their goal seems to be to pack as much tourists in a given space. Open decks seems to have disappeared in this quest. Passengers are hermeticaly sealed inside in an unreal world afloat, insulated from the elements. Gone are the beautiful sheers the ss United States, Normandie or the Queens had. These floating cattle cars seem incapable of going from one ocean to another in safety. Naval architects enlighten me please, are they safe in heavy weather like the N. Atlantic in mid Jan. or only in a calm Caribbean ?? For me they certainly are not beautiful but that is only my taste.

Ian McColgin
12-20-1999, 10:06 AM
And you see the same lamentable tendencies in the tupperware-ginpalace-tunatowerterrors, with saran wrap windows and airconditioning . . .

TomRobb
12-20-1999, 11:44 AM
Agree they're butt-ugly. You'd think the the Captain would want to wear a mask lest anyone he knows recognize him. The QEII still looks like a real ship and you can still cross the N.Atlantic on her - a nice way to get to England and back if you have the time.

Scott D. Rosen
12-20-1999, 12:25 PM
They sure are ugly as hell.

Just guessing here, but I think they use electronics and mechanics to make up for poor design. Their satellite nav, weather and communications systems can keep them away from bad weather (or so they think). While their computerized stabilizing systems hide the fact that they are "top-heavy," have too much windage and would otherwise roll like a bathtub. The passengers don't know the difference and probably wouldn't care. I would even think that the passengers are the happiest when they see and feel the elements the least.

Ian McColgin
12-20-1999, 01:08 PM
But remember a couple summers ago when one of those cruisamatics slapped the dirt at Nantucket Shoals because no one noticed that the GPS/auto pilot interface had an error message up from Bermuda or where ever, and no one was looking out the window on a lovely clear night with every navigation aid in plain sight, and no one noticed the depth sounder record line getting closer and closer and closer . . .

Or on a smaller scale, that murderous buffoon who roared on auto pilot through the fog at Pollack Rip and sliced a charter fish boat in half, killing one of the guests.

'Course even nice looking vessels screw up - Wasn't it QEII that boomed down Buzzard's Bay ignoring the well understood phenomenon of shallow water squat and the fact that widely spaced soundings don't mean that there are no little speed bumps on the bottom.

We all make errors - not for nothing that I'm the life Commadore of the Kedgers' Club - and we sometimes make truely bonehead errors, but at least we're not piloting floating monstrocities that have the causes of destruction built into their very design.

Scott D. Rosen
12-20-1999, 01:37 PM
Good point Ian. I have no one but myself to blame for every one of my boneheaded moves. Generally speaking, the designer and builder did their jobs just fine. It's the skipper who has the occassional lapses.

BrianCunningham
12-20-1999, 05:54 PM
First I agree, they kinda look like Willy Nelson's tour bus. http://media4.hypernet.com/~dick/ubb/smile.gif

They are shaped squarish so they can fit bigger boats into docks.

They are actually 'power stabalized' meaning they have fins underneath they change directions to fight any movement.

Whay I'd like to know is what happens when the power goes out?

But there is hope check this one out
http://www.all-inclusives.com/windstar/images/shippic1.jpg

http://www.all-inclusives.com/windstar/windstar.htm

NormMessinger
12-20-1999, 07:01 PM
Oh, I donno, Brian. There is something not quite right about her. Maybe its the sails.

--Norm

Bob Cleek
12-20-1999, 10:49 PM
Only the good boats survive. Take a look at the old books and magazines from years and years ago... we don't have any franchise on ugly. In my opinion, some of Giles' reverse sheer racers and LFH's "lifeboat" whale decked designs are better left forgotten! LOL

J. Dillon
12-21-1999, 09:02 AM
Brian,
I doubt very much if that Wind Star vessel really sails. If she does 4kts with a beam wind in force 5 I'd be surprised, and then pointing up???? Those sails are up as a form of decorations for passengers to oggle at.

Scott D. Rosen
12-21-1999, 10:11 AM
Is that a square-rigger with roller-furling staysails? Eek Gad! Who designs those things and why?

TomRobb
12-22-1999, 08:36 AM
I thought that WindStar sank in one of last summer's hurricanes. It looks to be a sailing ship about as much as my pickup truck is a Mclaren F1 race car

J. Dillon
12-22-1999, 10:09 AM
Tom,
That might have been the the "Fantome" she sunk in hurricane "Mitch" 98. She was owned by the Windjammer cruises operated by Mike Burke. The New Yorker magazine has an interesting article concerning the incident in their Oct.11 99 issue. The "Fantome" looked very much like the "Windstar"

htom
12-22-1999, 10:18 AM
I -think- it's a four-masted schooner with transparent (what's the generic term for "mainsail"?) sails on white battens, from looking at the drawings on their site.

The designer's name isn't visible anywhere; perhaps he's had second thoughts. (I refuse to believe that a "she" could draw something so ugly.)

Fore, main, mizzen, and ... spanker?

Don Braymer
12-23-1999, 04:57 PM
Isn't there a scene in the movie Fantasia where hippos put on tu-tus and try to be ballerinas?

Some of these "let's be hip and put sails on the cruiseliner" schemes make me wonder...

Sail boats is sail boats and power boats is power boats, and when you mix the two together it can be a pretty awfull thing, but when take a horse designed to be a horse and try to make it into a part time bird by tapeing on some wings...

Let's just say Merry Christmas and wish them luck if they run out of diesel, and then the wind starts really blowing.

DonB

Dent Harrison
12-27-1999, 08:48 AM
To respond to the Dillon's original post, yes the cruise ships, though ugly as sin, are indeed very safe. The safety rules set by Lloyds and others for intact and damage stability, seakeeping, etc are very strict, much more so than for freight-carrying vessels. While they do look top-heavy, it is more illusion than reality. The superstructures are typically aluminum, and with several hundred tonnes of machinery well low down, not to mention perhaps a 1000 tonnes of bunkered fuel and lots of ballast, they are very stable. After a military ship, I would prefer to be on a passenger ship in rough weather over a freighter.

Indeed the sheer height of the superstructure demands that roll and stability are very finely tuned otherwise there would be too much sloshing in that swimming pool 100ft above the waterline!! To add to passenger comfort, active stabilizers in the form of flume tanks or wing stabilizers are added, but the ships must be inherently stable without these devices. They also must meet severe collision standards for flooding control, and have the most strict standards for fire and smoke control and evacuation.

These ships are also very fast for their size, usually 25kts or better, with typically 50- to 100MW installed power, of which 30- to 60MW would be for propulsion. These ships also use some of the most innovative drive systems available today from Schottel, an electric azimuthing podded drive which eliminates all shafting and gearboxes increasing efficiency by some 10%.

Usually the passenger vessels run amok more because of poor crew standards, which is common everywhere. It doesn't matter what type of ship it is or how well designed we make them, but if it is flagged in Panama or Liberia, owned by someone else, and crewed by yet another national crew, maintenance and good seamanship are bound to suffer.

Dent...

TomRobb
12-27-1999, 09:19 AM
Dent, Dent, Dent. You had to go and spoil it. Decent whipping boys are so hard to find. Ok, so they're marvels of modern engineering. They're still ugly. I get the impression that the less they look like a proper ship the more the cattle... er, paying customers like them. The bread and circuses thing? SWMBO, God bless her, for instance loves them. She wants pastel sunsets, soft breezes, shopping, head to toe - 7x24 - service and entertainment, and don't bother her with the real ocean.

TomRobb
12-27-1999, 09:31 AM
Oh BTW, what's an "electric azimuthing podded drive?" Sort of an enormous electric I/O? Or one of those weird tugboat cuisenart drives?

Scott D. Rosen
12-27-1999, 10:44 AM
Don't believe everything you read. Be critical. Weigh all facts carefully, in relation to the deepfelt prejudices and romantic misconceptions that you know in your heart of hearts to be true. Trust your prejudices--They've gotten you this far in life, they'll get you through this too. You know the truth: No boat that's that ugly can be any good. It's just plain common sense.

If Dent told you the moon was made of blue cheese, would you believe him?

[This message has been edited by Scott D. Rosen (edited 12-27-1999).]

TomRobb
12-27-1999, 11:34 AM
Well, he IS an engineer. I'm lucky I can even spell engineer. And I don't even own a striped hat. Yes it is a struggle to cling to common sense when all evidence is to the contrary, but I've succeded before so why not now. Or, perhaps tall & slabsided w/ grossly exagerated sharky bows and Roger RamJet styling will be the new esthetic paradigm. Here's our chance to be ahead of the curve for a change. I've always dreamed of a boat w/ a glass elevator and a pool. When I think of the Las Vegas dancing girls I could almost swoon. It is true, beyond dreams of mathematical certainty, that my boat needs dancing girls.

Dent Harrison
12-27-1999, 01:11 PM
Gentlemen, I never said that I liked how they look. I agree entirely that these floating hotels, except for a pointed bow, have very little resemblence to the grand queens of the seas of old. The only cruise ship that I have seen launched in the last 6 years that even starts to come close, at several miles viewing distance, is the ORIANA. She was built as a slender, fast, open passage maker.

In the office we are constantly pushing the nav archs to make the ship designs, no matter what the purpose, even an antarctic icebreaker, look proper and give the impression of strength, stability, and confidence. But if the height and proportions of a cruise ship are troubling, so too must be aircraft carriers. The cruise ships have very little weight up top, after all, cabins and joiner work are very low density stuff compared with the machinery and piping well below. Yet seeing is believing. These ships have lasted for decades, and fewer sink than planes fall out of the sky, so there must be something fundamentally correct, aesthetics aside.

As for azimuthing drives, I just completed a 6 month preliminary layout on a 200m ship with these things, they do have many advantages. You essentially have very large electric outboards, but with the motor submerged and directed connected to twin propellers, one fore and one aft rotating in the same direction. There is no gearbox, and the whole thing pivots about the vertical axis to give you full thrust in any direction. I think you can see them at www.schottel.de (http://www.schottel.de) is their website. They are best suited for ships with a very high electrical power load like a cruise ship, or the ship we were working on. They are expensive compared with conventional shafting, but the flexibilty in layout, and efficiency of 6,600V drive works out well over a 30 year life.

Cheers, Dent...

Dent Harrison
12-27-1999, 01:18 PM
Further to my last post, for thems that are interested, at the www.schottel.de (http://www.schottel.de) website, go to Products and Services, then the Siemens-Schottel Propulsor (SSP). To give a sense of scale, there is a little outline of a person on the top of the casing, the other round things up there are hydraulic steering motors, blowers, and slip-ring affairs. Again, only for thems what are interested. I don't work for Schottel and make no endorsements as to their products.
Dent...

J. Dillon
12-27-1999, 01:53 PM
Dent,
Thanks for adding to our pool of knowledge. I do appreciate that you urge your colleagues to come up with something more pleasing to look at (for reference see Scott's recent post with pix).

Now when it comes to Aircraft Carriers they are beautiful ( Can beauty be in the eye of the beholder?) I helped maintain one for three years, dabbing on many coats of paint. By the way is flexability built into those new floating hotels ? I remember in heavy weather with the aircraft off the ship, seeing her flex when viewed from aft looking fwd. on the hanger deck.

TomRobb
12-27-1999, 02:24 PM
Not to argue the point. I don't doubt a German engineer's estimate of efficiency. I had thought that converting from heat energy in the fuel to mechanical energy turning a generator to electrical energy and back to mechanical energy at the props involved losses at each conversion. How do they manage to get more efficiency rather than less? Just curious. If that works should I get a honda camp generator and a trolling motor for my batteau? And Oh yes, for the guys she manages to bring home in one piece, carriers are drop dead gorgeous. I guess it's an emotional thing.

BrianCunningham
12-27-1999, 05:30 PM
Yup Windstar's actually do work

They are totally run by a computer and work in conjuction with the engines. In other words it's a motorsailor.

BTW they built it
1) to save fuel, and
2) because people were complaining about "ugly cruise ships"
http://media4.hypernet.com/~dick/ubb/smile.gif http://media4.hypernet.com/~dick/ubb/smile.gif http://media4.hypernet.com/~dick/ubb/smile.gif

Dent Harrison
12-27-1999, 06:51 PM
The following only applies to large ships and not the wonderful wooden yachts this forum is devoted to. In general, the efficiency of the power train of an electric drive is lower than a simple mechanical engine/gearbox/CP prop. However, the azimuthing thruster gains its efficiency in the "quasi-propulsive co-efficient" and makes up for the electrical losses, and then some.

Essentially you lose about 35- to 45% of your power in the propeller and the propeller/hull interaction. This is compared to the 3- to 6% losses in the geartrain or electrical system. So a relatively small gain in the qpc means large gains at the engine. With a podded propulsor, the propeller "sees" free water without the interference generated by the hull in a single prop installation, or by the shafts and bosings in a twin shaft. In addition, you have the freedom to align the axis of the propeller with the flow under the stern of the ship by angling the shaftline upwards aft by a few degrees. With conventional shafting, the best you can get is horizontal if you have sufficient draft and depth to accomodate the gearbox and engines getting into the double bottom. Lastly, you don't have the drag and losses associated with the rudder.

Since cruise ships for example spend a large portion of their time manoeuvring in and out of port, the ability of applying full thrust in any direction is a real benefit to ship operations. The flexiblity of layout is also very beneficial in order to provide separation and redundancy, and divide up engine compartments fore and aft in the case of a military ship which cannot be done with conventional shafting. It is not a panacea solution, but where high manoeuvrability and large underway domestic electrical loads are required, an all-electric drive is a competative and economic alternative. Many of these new cruise ships are fitted with either Schottel's or ABB's podded propulsors for these reasons.

The hull form for using an azimuthing thruster must be developed from the outset, it is not something which can be retrofitted. The long term savings from the lack of a gear box, long shaft lines and complex cp prop system, and the overall increased efficiency usually pay back the added initial cost to ship owners. It is not for every application, but it is nice to use where warranted.

Thought you might be interested.
Cheers, Dent...

Bob Cleek
12-28-1999, 01:29 AM
Okay, here's one for the propulsion engineer in you, Dent. Do you think there will be any cross-over applications in the small boat marine context for the emerging electric motor technology they are developing for automobiles? They are talking about those hybrid power plants with a tiny turbo generator that charges a superconductor battery... claim they go forever on a thimbleful of kerosene and produce zero emissions, very light and compact. SOUNDS just like the ticket for a yacht, especially given the reliability and flexibility of installing an electric motor as opposed to a traditional powerplant. (See, guys, I'm not THAT hidebound!)

redjim777
12-28-1999, 10:06 AM
You have to remember that the owners only concern is cost & profit per head (I did 2 yrs as a cost analyst for a hotel.). Once launched they would probably jump through hoops to avoid any additional capital expense and do everything in the world to keep maintenance costs low. In other words everything plastic and easily replaceable and no real workmanship put into her. They probably put a pointy end on her so that the passangers can say "bow", "stern" and learn all of the other neat words.

It's my opinion that the really beautiful ships were the four mast sailing ships.

You know, when I was in the military I did'nt appreciate all of the nice long walks they took us on, now looking back, I realized that I saw alot of the country from a perspective that I otherwise would have missed. I think the same holds true for crossing any body of water in a sailing ship rather than a cruise ship.

Oh yeah, I have to work now, Happy New Year!

TomRobb
12-28-1999, 12:32 PM
Thank you very much, Dent. It is, truely, facenating. The pix looked like nothing so much as an enormous trolling motor on steroids. Do they use them on tugs for the manouverability? There's an old guy near here who runs a decked canoe/kayak with a trolling motor. There are what, three or four horse ones now? He looks to be the picture of serenity tooling about the lake in his effortless quiet little boat. Ought we begin to look at designing our boats w/ these motors in mind? Something like Bob Cleek's near perpetual motion machine.

Dent Harrison
12-28-1999, 08:15 PM
I read the SAE's "Automotive Engineering" each month and haven't really seen anything yet that jumps out as being cross cultural, except for the global consensus that buses and automobiles are moving in the electric direction. We will benefit when the energy density of storage batteries tops lead acid, still the leader by a wide margin, and can put more storage capacity on board for the same weight/volume.

For me, I think that the move away from fixed shafting in the commercial world will eventually make it to the pleasure market, water jets have, so why not these. For example, instead of a fixed shaft keyholed into the aft end of the keel/rudder, a small retractable, electrically driven "L-drive" in its own well would really help both sailing and powering efficiency. When retracted, it is enclosed with a small door (not watertight) to reduce sailing drag to near zero. Deployed for powering, you can take advantage of putting the largest, beefiest, most efficient prop with a nozzle if you desire to really slow down the rpms and make all your gains in efficiency at the propeller end. This can be achieved because you are not worried about sailing drag anymore. Then instead of a 300hp prop and engine rig, perhaps a 150hp set up will get you the same speed with all the savings acrued. The electric motor is nothing to be worried about, you could get yourself a simple DC motor and run straight from the battery bank. Then your genset only has to charge the batteries and can run at constant speed, rather than cycling while powering. Personnally I would go with an AC system but that is just me. The DC motors and controllers are commercially available for use in electric cars, forklifts, and the like. But it does mean that there are no shaft seals, no alignment problems, no couplings to watch and maintain, and you can put both the propeller and engine where ever you please, optimizing the location for both independently. Essentially you do have a big trolling motor going up and down. Probably not a new idea, but new technologies can make execution much better than in the past.

As for coming technology that is realistically usable (unlike fuel cells, etc) I would watch for Sterling Cycle engines, and micro gas turbines. Why? They are continous combustion machines with much higher efficiencies, and almost no vibration! The micro gas turbines have been developed by United Technologies (if I remember correctly) and are in the 40- to 150kW range. They run at 100,000rpm driving a simple generator. Essentially they look like a truck turbo-charger. But they are quiet, efficient, and are being tested and readied for the home market for electrical generation from natural gas. It is just as easy to operate them from Diesel or Kerosene. The same goes for sterling engines.

What ever the case, I think the future is going electric. I read the publication "Professional Boat Builder" and I think there is some real concerns about the ability of yards to design and execute proper electrical set ups. Once you move away from 12- or 24Vdc the possibilities are enormous. Even running a battery pack on board at 120Vdc (in series rather than in parallel) reduces losses and the size of motors and generators considerably at no real increase in cost. This allows the use of solid-state inverters which are light and inexpensive to provide pure sine-wave AC power for all domestic loads which is no more complex to wire than your house. The real advantage of going electric, properly done, is the lack of maintenance requirements for years or decades.

Anyway, just some thoughts. Happy New Year to all! Cheers, Dent...

Ed Harrow
12-28-1999, 09:37 PM
Dent, fascinating, thanks for the education.

Bob C, how'd you manage to pass up "podded propulsor" and "azimuthing drive". I'm really pretty disappointed. :)

Oh, Dent, I was recently taken to task for using Sterling as oppossed to Stirling. If recollection serves the guy's name was Stirling, but I've not managed to get off of my duff to confirm it. What's your take?

[This message has been edited by Ed Harrow (edited 12-28-1999).]

Bob Cleek
12-28-1999, 09:43 PM
Did I miss something?.... Ah, Altzheimers... all the new friends you meet...

TomRobb
12-29-1999, 08:46 AM
Dent, I've seen what you mean about the efficiency of gas turbines vs piston engines. At the telephone co. we had 2 huge railroad engine type diesel engines, each larger than my old Dodge van, in the basement of our local central office for emergency backup power. (4 @ 10,000 subscriber exchanges) About 10 or 12 years ago they were replaced by a pair of gas turbines about the size of an old nail keg or a peck basket. In our situation we needed to buss very large currents all over the building. Wire losses w/ dc over any distance forces the use of copper busses the size of Structural steel I-beams. Is that why you prefer AC? And for vessels running at hull speed or less is a nozzel around the prop the trick setup?

Ian McColgin
12-29-1999, 02:46 PM
Ed, maybe Dent can get it for sure, but I think Stirling makes incredible model engins and the sterling engin is some kind of a bit beyond experimental giz, but I don't know its operating principles.

Dent Harrison
12-29-1999, 02:48 PM
I stand corrected, Stirling it is according to my old thermo text. The gas turbines have a much better power/weight ratio than diesel engines, which is why, with the exception of a few german WWII planes, diesels have not really made it into commercial aviation. In commercial sizes (5- to 50MW), they have a small penalty in efficiency compared to diesel engines at full load, but the new micro turbines better the standard diesel in the power ranges we are interested in. As for nozzles, that is more a question for nav arch types, but generally they are limited to usage below 15kts, so if this is below your hull speed, it is worth looking into.

The telephone bus work is probably 48Vdc and yes, the currents can be huge, but since this is the operating voltage, everything is geared towards it. With AC, you fundamentally have the ability to change your voltage levels with ease via transformers which you cannot do with DC, therefore you can tailor the voltage to appropriate load. For example, on one ship I recently completed, the generation voltage was 3.3kV, which was used for all large consumers as is including the podded propulsors, bow thrusters, and some huge pumps to actively heal the ship in ice. This meant that the cabling losses were minimized running all over the ship. We then stepped down to 600V for general service, and then down again to 240 and 120V for domestic loads, and finally 24Vdc for emergency. This is typical of an electric ship setup. In general ships, the ship service generators are usually just 600- or 440V and large loads like bow thrusters either have their own direct drive diesel or very large cabling to handle the current. After all, 1,000kW of bow thruster needs about 1500A at 600V, or just 300A at 3.3kV. Which would you rather have?

Interestingly, one ship design we were working on was a competitor of an existing research ship which was conventionally arranged with a total of 11 V-12 engines totalling some 132 cylinders. Icebreaking and trolling for weeks brought many complaints from the crew and scientists that the ship was extremely noisy-no kidding! In our design, I was able to replace all that with just 4, 8-cyl in-line gensets for complete propulsion and ship service load. We reduced the installed power by 10% and increased speed and range by about 20%. Our maintenance costs obviously will be cosiderably lower, while our redundacy is higher than the existing ship, but the first cost is higher which naturally meets with resistance. It all depends on the owner's time frame and foresight I guess.

Cheers, Dent...

Paul Frederiksen
12-29-1999, 09:25 PM
If I remember from my Army days, the M1 Abrams tank runs on a turbine. It produced about 1500 hp and was not much bigger than a shoe box. BUT, the transmission necessary to reduce the high rpm down to something useable was about the size of a VW bug. I saw one once pulling up a hill in heavy mud. It was moving at a walking pace when suddenly the 16 lugs holding the drive sprocket sheared off. These lugs were at least 1 1/2 inches dia. Very impressive power.

Oh, and they are real nice to stand behind on a frozen early morning out in the bush (if you can stand the smell).

Phil Bolger and Friends
12-29-1999, 10:03 PM
- A plain Schottle SRP (5-digit cost)will give you 'clean water' if you mate it to a clean hull.
- So will much lighter units for 40HP and a minor 4-digit expense.
- For a few $$$$ more the twin-prop STP will give you clean water and less prop load.
On the scale of boats ever discussed in WOODENBOAT the following is worth considering:
- Any long-legged outdrive will offer 'quite' clean water to the prop - all depending on hulls. If designed into the boat from the first sketch it will lift clear of the water for sailing and much more importantly for just sitting at rest. And you can untangled potwarp while remaining dry and safe - depending on design - or change damaged props at sea...
- Any long-legged outdrive will minimize corrosion/electrolysis to the barest minimum.
- And perhaps most importantly it reduces the holes in the boat by one big one.
Which forces the next point:
- eliminate ALL throughhulls/forget about 'fascinating' sea-chests fo all the obvious reasons. Solutions abound to manage traditionally 'wet/salty'-valved mechanical concerns. Our 51' Oak on oak RESOLUTION is now stuck with just the shaft throughhull as modifying that end of the boat would induce cascading consequences. But now on the eve of another New England winter with likely power-outages, she'll make power sitting high and dry on land in our front-yard running fir as long as you have clean fuel, turning any generating device you want to couple to that 90HP diesel. Even M.Bray might feel compelled to consider her construction traditional enough, 7000+ still shiny silicon-bronce screws, coppersheathing, and all. But just propulsion-technically she's already far away from perpetuated conventions about the 'proper wooden boat'. Still low-tech, even a 22 year old wooden live-aboard can be bumped to a lower grief level of ownership.
Last point: E-power in boats is old news, despite periodic 'rediscoveries' of the subject matter - similar to the 'sea-sled' evergreen... True the SCHOTTEL/SIEMENS technology is a serious step forward, but in the 'pleasure-craft' or even smaller scale working craft up to 100'fishing-vessels many more obvious/doable/cost-effective/ utility-enhancing 'refinements' are possible/ necessary(!) without major budgets to just plan the 'systems'- never mind buying them.
Much talk about electric boats focusses on drive rather than storage and finally/firstly(?!) power-generation. Major mags gloss over the very core that make for any electric motion ie. generation and storage of power. Often there is too much 'perpetual motion' flavors pervading the reporting on E-power and a pseudo green giddiness in some quarters that is embarrasing. Whether it is plain lead and acid or massive electric forces to which at least crew will be exposed to, many ugly questions of production, use, and disposal are merrily ignored. Every year another fabulous 'E-drive'forbthe pleasure-boater hits the PR presses and off we go... SCHOTTEL/SIEMENS yes - electric drives on your favority ALDEN typically unrealistic - until furthjer notice. And don't hold your breath. Pulse-width-modulation etc. are true advantages but we're barely making it past the breakwater yet.
Opinionated Summation:
1. You can put any E-drive into any boat, pile in the battery Ahs, an you're still stuck with an nation-wide AC grid of 110V at typically 15-30Amps with 50 findable... Your foot-per-day bill will vastly exceed that for kW transmitted at very leasurely rate.
2. On WOODENBOAT-scale boats/vessels diesel-electric drives have just about no purpose in an age of cheap engines, good transmissions (typical big-ship reason for diesel-electric), and many ways to put the power efficiently into the water.
3. As long as traditional 'hang-ups' dictate significant cost and often endless grief from deeply conservative hull-shapes, underwater-'hole'-happy systems design, one-season utility, and other purposefully and often client-demanded designed-in degradations of potentially useful proposals, serious concerns over relative versus actual efficiencies and inefficiencies of drive systems are academically fun and very relevant in big-ship design, but on the 'end consumer level' of rather limited relevance.
We've designed and lived with a small electric boat for 4 seasons. And we've been waiting for a long time for either 'better batteries' or the fuel-cell 'for everyone'. It'll take a while yet...

TomRobb
12-31-1999, 09:33 PM
I'm tempted to quote Jack Benny,"Well!"
Probably not much to say now except that what the big guys on the block are up to is always interesting. The intreguing thing about electric, for me, is the quiet. Imagined efficiencies, or the lack of them, are irrelevant. If I wanted to travel efficiently I'd ride a bike of take an airliner depending on the distances involved. The boats are for fun. I'm not likely to earn a living w/ one. aerospike hypersonic aircraft engines or ion drive space craft are interesting too. I doubt I'll ever get any firsthand experience w/ one of those either. Since this the dawn of a new millenium, (spare me your 2000/2001 calender arguements) and predictions are all the rage, it seems safe to suppose that as automobiles drift toward electric or hybred electric propulsion, even pleasure craft will follow as-and-if the nuts & bolts become cheaper and more reliable. Someday. It's an interesting mental toy in the mean time.

Bob Cleek
01-01-2000, 02:22 PM
Is this THE PHIL BOLGER? And, if so, just who are your friends? LOL... Great comment. Certainly mirrors all the conventional wisdom I've been able to scare up on the subject. I sure agree, the fewer through hulls, the better!

Welcome aboard! (He he he... I just KNEW your boat wasn't plywood!)

Phil Bolger and Friends
01-02-2000, 08:32 PM
RESOLUTION was designed during an anti-plywood period...! Mistake from all- traditional construction were predictable, costly, and would put her at risk during a holing. Oak-on-oak, with mahagony well above waterline and eastern cedar for decks and bulkhead reflected 'proper thinking' re wooden boat canon. But the deck leaked spoiling many a good book (no plans though...), rotted of course..., and the bulkheads have opened up to a degree that only caulking the old fashioned way would keep engine room truly separate from cabins and forepeak from stateroom. Thus even with stern and bow-compartments undamaged in a collision, she'll likely 'weep' through the pretty strip-built bulkheads as anybody could have predicted. Since '92 she has had ply/glass/epoxy over a rebuilt cedar deck and some flex-schmutz in the bulkhead cracks. Remember the story when on a well-performing sizable strip-built boat, crew kept hearing 'gunshots' somewhere aboard while making a passage offshore, only to discover in the next port that the planking had swelled and thus pushed itself away from bulkheads, now free to move with the sea... Worked fine for many years after initial shock wore off. The 'gunshots' were bent frames parting in tension!
Plywood is preferable in many boat-building projects, where preoccupation with intricate shapes are practically irrelevant for performance, such shapes very costly to assemble, comparatively fragile from limited thickness, and definetely vulnerable with all those seams - if you can find decent lumber anyway. Example: A 38+'x9'x18"/22" 5000 NM range powerboat for two in which 2" bottom and 1" side thickness offers pretty good survivability, thermal qualities, dusty bilge, and unsinkability - currently built largely singlehandedly in Florida. Started last summer and will be out of the path of the third hurricane to hit the same spot by next summer... Of 650+ designs done here so far, probably about half were compound shapes in just about all materials - usually wood though. The other half is plate-material based and is much more likely to get built, and worked longer and more successfully for the initial investment. There is a place for elaborate shapes, but in the majority of cases NOT going for the high-bucks softer shapes is the reason the project can actually get realized!! Dreaming is fine, building and cruising for less is better. Too many people don't think they can have performance on the water because of limited budget. Not necessarily so. And unlike what many folks seem to think, during a successful passage, the simpler, stouter, more affordable ply for instance get hardly noticed from the cockpit... If some distant brass-buttoned dock committee of reactionary persuasion issues a verdict as to the 'proper wooden boat' perhaps one should stay offshore from them. Dogma does not add to the budget. Those 'committees' of 'good taste' used to be called the 'rocking chair fleet'.

Phil Bolger and Friends
01-02-2000, 08:49 PM
PS. Rent a current Cadillac limo and enjoy the quiet - with exhaust pipe and muffler right under your seat. Dry-exhausted... Combustion-engines are only as loud as you allow them to be. And if you stay away from more saltwater in the boat from 'waterlift' muffler concoctions she'll be quiet even when she's frozen in January and the wet exhaust system is hard. Compare certain shielded 4-stroke outboard with a ruined ring-gear from restarting while it already runs - couldn't hear it - to the 'merry' pitter-patter of little and big feet, plus bear-cans etc. while you're waiting for that charge to slowly feed your batteries. The circular reasoning behind the 'diesel-electric' drive to feed the batteries 'at sea' then closes the circle if proposed as 'a way out'. A smooth gasoline engine, oversized and then de-tuned with a lame camshaft etc., properly marinized of course (ignition and alt.)with a sweet sounding ('72 Chrysler Imperial) glorified MIDAS muffler well-wrapped etc. will purr at very low 4-digit rpm and likely be drowned out by bow-wave, gulls, jet-skis etc. 'Smooth' and quiet is possible now - off-the-shelf, affordable, and with as much range as you can design the boat around.

Phil Bolger and Friends
01-02-2000, 08:52 PM
PS. Rent a current Cadillac limo and enjoy the quiet - with exhaust pipe and muffler right under your seat. Dry-exhausted... Combustion-engines are only as loud as you allow them to be. And if you stay away from more saltwater in the boat from 'waterlift' muffler concoctions she'll be quiet even when she's frozen in January and the wet exhaust system is hard. Compare certain shielded 4-stroke outboard with a ruined ring-gear from restarting while it already runs - couldn't hear it - to the 'merry' pitter-patter of little and big feet, plus bear-cans etc. while you're waiting for that charge to slowly feed your batteries. The circular reasoning behind the 'diesel-electric' drive to feed the batteries 'at sea' then closes the circle if proposed as 'a way out'. A smooth gasoline engine, oversized and then de-tuned with a lame camshaft etc., properly marinized of course (ignition and alt.)with a sweet sounding ('72 Chrysler Imperial) glorified MIDAS muffler well-wrapped etc. will purr at very low 4-digit rpm and likely be drowned out by bow-wave, gulls, jet-skis etc. 'Smooth' and quiet is possible now - off-the-shelf, affordable, and with as much range as you can design the boat around.

TomRobb
01-03-2000, 07:54 AM
It's great to see P.C.B. here. I hope this won't be the last. It would be REALLY interesting to hear from the Friend(s). Imagine the stories she could tell.... In the meantime I feel like Job after God told him to shut up and know his place..."Were you there when I created Leviathan for the sport of it?" I shall be content to keep still in the face of authority. How 'bout you Bob?

[This message has been edited by TomRobb (edited 01-03-2000).]

Scott D. Rosen
01-03-2000, 11:00 AM
Yeah, Bob. What was that you were saying about plywood? Now you have a chance to pick on someone your own size (or bigger). LOL

Scott D. Rosen
01-03-2000, 11:05 AM
Re: dry exhaust. Some months ago, someone in Northern climes posted a question about how to keep his engine running through the winter. As I recall, he didn't want to use dry exhaust because of the problems created by the heat generated by the exhaust piping. I've seen lots of workboats with dry exhaust and some larger cruising yachts too. Obviously it works. Are there any tricks to installing a dry exhaust? Any problems or things to be especially concerned about?

Bob Cleek
01-03-2000, 01:03 PM
Well, as I've said here before, and nobody ever seems to remember, I've owned something like FIVE plywood boats! One, a 25 foot gaff ketch, a dory, and the rest small sailing dinks. I don't disagree with Phil's comments at all, if you are looking for the ends he mentions. I would say, however, that an even faster way to get out on the water, if that's your primary goal, is to buy a used boat and rebuilt it to suit.

Having spent many years held hostage by an old GrayMarine 4-112, I can attest that there is nothing like a heavy gasoline engine that never has to get up to more than about half of its potential to reach hull speed... being enthralled with what a lighter mill might do to raise my aft waterline (the boat was designed for no engine, after all... and my expanding waistline in the cockpit didn't help much either) I was anxious for an excuse to repower with one of those little diesels, but the GrayMarine just would not die! I finally grabbed an "offer I couldn't refuse" on a three cylinder fresh water cooled Westerbeke GAS engine and boy, am I glad I did. The fastenings are still in the boat, and the fillings are still in my teeth.

My "anti-playwood" posture has become something of a fun joke in here, but really, my primary criticism is aimed at trying to make plywood serve as planking for small boats designed to be built carvel. I don't think it is easier, cheaper, or better... and I'll keep saying that no matter how wrong anybody proves me! And, don't get me started on why you shouldn't bother thinking about building that ocean cruiser out of glassed CDX! LOL

Certainly, for shapes intended for plane sheathing, plywood may be the material of choice. Traditional plank is no more appropriate on a boat designed for ply construction than vice versa.

If you want to get out on the water fast, if you don't want to take the time to build traditionally, if you want a light boat and if you want to use techniques which don't require a lot of arcane geometry and woodworking skills, plywood is definitely the way to go. (It also makes good sense if you are making your living selling boat plans and there's nothing wrong with that!)You will, however, have to accept the fact that no matter how good a job you do, you will in the end have a plywood boat. If that's okay with you, definitely go for it! If you want a boat that is going to place in the Port Townsend Festival in the next hundred years or so, you will probably have to build a traditional one.

Art Read
01-03-2000, 02:09 PM
Re: The sailing abilities of "Windstar".... I read an article by her skipper recently, (I think it was in Latts & Atts"?) He wrote of sailing her into an anchorage at Jost Van Dyke without her engines. Came in on a close reach @ about 10 knots, disabled the sail trim computer, (and shut off all the warning klaxons!) rounded up about a quarter mile shy of the mark, rolled up his headsails, manually overrode the computer to backwind the rest and let go just as she started making sternway. He swears that when he re-engaged the computer, it went "Hmmmph!" as it brought the sails back amidships.... When he rang up the engineroom and ordered "Finished with engines..." the chief replied, "Finished??? You never even started!" (He does go on to say that all the passengers who'd come on deck to see the anchorage probably never realised he did anything "unusual"....)

J. Dillon
01-03-2000, 02:46 PM
I'm sure a good skipper when he knows his vessel can do that even with a "Windstar."
Art, did the article say how far from the beach he dropped his hook ? That anchorage from what I remember is sure pretty crowded.

Scott D. Rosen
01-03-2000, 03:56 PM
Sailtrim Computer?! Just call me a dinosaur. I'm a lifelong rag-bagger, but it somehow seems better to me to be cruising under power with your hand on the wheel and an ear to the engine, then to "sail" with an autopilot and a sailtrim computer. For that matter, why not install an electric drive, with batteries charged by a wind turbine and solar cell combo? That way you can cruise under power but still tell all your friends that you rely on the whims of nature for your propulsion.

J. Dillon
01-03-2000, 04:16 PM
Scott, You're right this "gadgetry" has gone too far. Reminds me of the time I went to a boat show in NYC. One of the exhibitors was demonstrating the virtues of his fighting chair. It seems his product reeled the fish in for you when it sensed a definite strike. All you had to do was boat the fish, but they were working on that one too.

Dent Harrison
01-03-2000, 08:38 PM
Appologies for the lack of continuity in this thread, but I was talking with an old friend today from MAN B&W who reminded me that the QEII is also diesel-electric. She was repowered some time ago (15 years I think if memory serves) and has quantity 9, 14,450hp diesel gensets (from MAN of course)totally some 130,000hp intalled power. Drive is through two convential CP props powered by constant speed electric motors. Her cruise speed is 28.5kts with a top speed of 32.5kts and carries about 5,000tonnes of bunkered fuel. For a civilian ship that is about 980ft long, that is impressive!

By the way, some may have the opinion that I am a techno-junkie. Just the opposite, my goal is always to meet the criteria presented with absolutely the least technology in the simplest arrangement. The fewer moving parts, the fewer repairs, and the few breakdowns. But my job requires that I keep abrest of the latest developments, which I am happy to share as information with you all.

Anywho, again, appologies for the interuption... :)

Dent...

TomRobb
01-04-2000, 09:33 AM
A while back, on the Travel channel or maybe the Food one perhaps, they did a tour of QEII. The engine room, which sadly got less air time than the kitchens, was most impresive. Rather like the machinery spaces of the Krell in the 50's classic si-fi movie "Forbidden Planet." Bob has a point. Substituting ply for cedar plank on a design intended for rivited clinker may not be kosher, but what about one of Ian Oghtred's pretty glued-lap skifs? He designed them that way.... His football - his rules? And P.C.B.'s idea of a saltwater I/O w/ no underwater thru hulls (air cooled engine?)might make for more peaceful sleep. Especially if you could somehow hide the thing.

BrianCunningham
01-04-2000, 04:49 PM
How about this cruiser?

The biggest cruising catamaran ever built

http://admirals.com/doucefrance/plan.jpg

http://admirals.com/doucefrance/

tmaccabe
01-04-2000, 06:27 PM
Hey, is that Kevin Costner?

BrianCunningham
01-04-2000, 06:58 PM
**** you have good vision!

steve sparhawk
01-05-2000, 03:29 PM
HURRAH, Phil! I knew I hadn't been reading your stuff in vain. Technological understanding is great and even better when it is mixed with common sense. Thanks for your most generous contribution.

Being a tinkerer, I am always looking for a quirkier adaption of a simple method to a complex problem. We tend to escalate almost anything we touch and before we know it we have a giant monster of a solution which is more of a burden than the initial problem. The more I discover the complex propulsion systems that are dreamed up, the more I want to make sure I have a good set of oars stowed somewhere.

Art Read
01-05-2000, 04:45 PM
Couldn't get page two to load... Sorry folks!

Don Z.
01-06-2000, 03:33 PM
And speaking of Electric drives, saw this from Reuters:


U.S. Navy plans ``electric drive'' warship

WASHINGTON, Jan 6 (Reuters) - The U.S. Navy on Thursday announced plans to
use revolutionary ``electric drive'' in its new class of 32 DD-21 destroyers,
which could begin joining the fleet in a decade at an estimated overall cost
of $25 billion.

The stealthy new warships would still use a diesel or turbine engine. But it
would both propel the DD-21 and generate electric power, unlike current
warships which have bulky separate engines for movement and electricity....

Scott D. Rosen
01-06-2000, 05:14 PM
For $25 Billion, they ought to be able to make those ships fly.

Chris Lasdauskas
01-09-2001, 07:44 AM
Hey Ian McColgin -
I know everyone was excited about cruiseships and podded drives, but you let this comment from Bob Cleek slip right past you http://media4.hypernet.com/~dick/ubb/smile.gif
"we don't have any franchise on ugly. In my opinion, some of Giles' reverse sheer racers and LFH's "lifeboat" whale decked designs are better left forgotten! LOL"

I know he said 'some' but he _might_ be referring to the Marco Polo ... http://media4.hypernet.com/~dick/ubb/smile.gif

Chris

Alan D. Hyde
01-09-2001, 09:16 AM
This is a great thread, with many contributions which I have thoroughly enjoyed.

In 1994, before her last major refit, I had a tour of the engine room on the QE2, looking over the MAN diesels and taking photos, and then spending an hour or so on her bridge. Originally built with turbines, she is now diesel-electric.

The difference between the QE2 and most of the recent cruise ships of which I have been aware (and it sounds like I may be behind here, from what Dent says)is SPEED.

The QE2 is the last of the ocean greyhounds.
The Norway (former France) has been de-powered to save money, and may not make even 20 knots. The QE2 will do perhaps somewhere around 40 (they won't say).

There was a book a few years ago on seaworthiness, which called it "the forgotten factor." In the context of modern liners, the forgotten factor with respect to seaworthiness itself is speed.

When my oldest daughter was crossing to Southampton on the QE2 late in 1994, they used their speed to get out of the path of a hurricane; a slow vessel would have had to stick around and take it.

Are the negative consequences of the drive for economy (and profitability) which were resulting in slow vessels, perhaps being
blunted by new technologies which permit both speed and economy? This is the impression I get from reading some of your comments, Dent.

Or are these innovative approaches an exception to the rule, found on a relatively few vessels among the fleet as a whole?

Performance attributes aside, many of these newer vessels are certainly ugly to my eye. QE2 is a beauty who has aged gracefully, however.

Alan

P.S. Somehow I didn't see Dent's remarks (01/03) on the QE2 above. Dent, she's not strictly a civilian vessel; the Royal Navy has rights to her when needed (remember the Falklands War) and helps to subsidize her.

Last I knew, the speed figure you quoted was an admitted speed, but there was something in the language they used which led me to believe that she might in fact go quite a bit faster.

(The reason I took the tour, by the way, was that I was going to do an article for the USPS "Ensign" magazine, focusing on the seaworthiness of the QE2. When this article was about done, she ran aground, and it didn't seem like a good time to print it. Problems with her refit followed, and the article never was completed or run.)

[This message has been edited by Alan D. Hyde (edited 01-09-2001).]

Ian McColgin
01-09-2001, 09:47 AM
Yeah. Some folk think the old swaybacked mule has a nice shear line . . .

Some think "de gustibus non disputandam est" but I think aesthetic and other values are the most fun to argue about.

When I taught philosophy one of my favorite in class surprises was to set a milk bottle and a fine vase on the lecturn and tell the class to spend the next 12 minutes writing about them . . .

The Marco Polo is not in the Bounty class for beauty but she has other virtues. Grana has that huge cabin trunk from the foremast aft which really spoils her look - so much so that my firends are really struck at how pretty she is in my rebuilding plan that is essentially a flush deck to the forward end of the present cockpit and a pilot house from there back. Actually makes her prettier than how LFH designed her. And once I have a high roach on all three sails, even the stumpy rig will look pretty good. But she's not a boat that wears ornament well - no turned and varnished taffrails.

My own boat aesthetic breakthough came as I got to know how incredibly fast and seaworth the little old Cutless was. 22' of reverse shear, reverse transome, hard bilges, fin keel - everything I'd been raised to despise but she's il pipistrello fuori di inferno.

And, of course, reading Bolger's book will either open your mind or drive you to drink - no middle ground.

Some people are aestheticly limited. They like their women only long legged and blond, or their men only narrow hipped and lantern jawed, or their boats only mahogoney bright baby bootleggers or their horses only dishfaced arabians or whatever . . . And some of us are so open minded that we're downright promiscuous.

I value wholesome, healthy and strong most of the time but even I've had fun with some styrofoam, tyvek, and an anorexic with a nose ring . . .

None the less, Bayliners should be sunk on sight.

BrianCunningham
01-09-2001, 11:13 AM
I was watching Speedvision ( cable TV ) the other day. It had a piece on a one of the new sailing cruising ships. The type where the passengers are encourage to go aloft.

at the end of the article the owner made the comment that they are preparing to construct another as a fully rigged ship.

It will be nice to see another square rigger out there. http://media4.hypernet.com/~dick/ubb/biggrin.gif

Chris Lasdauskas
01-09-2001, 09:37 PM
Ian, Ian, Ian.... wash your mouth out ! http://media4.hypernet.com/~dick/ubb/smile.gif

Grana don't listen too him, he's been associating with the aesthetically challenged too long!

I think the Marco Polo design is one of the most beautiful ever - and they aren't 'stubby' masts they are 'purposeful', and 'practical' and beautifully in proportion with the rest of the design.

http://albums.photopoint.com/j/View?u=1442723&a=10824637&p=37597478

http://albums.photopoint.com/j/View?u=1442723&a=10824637&p=37597480

See!

http://media4.hypernet.com/~dick/ubb/smile.gif
Chris

[This message has been edited by Chris Lasdauskas (edited 01-09-2001).]

Ian McColgin
01-10-2001, 08:49 AM
Grana always forgives me 'cause she knows my love, though wayward, is true.

But if you glance at the pix in the sailing in cyberspace bit (last seen around July 4) you'll see why I'm gonna take a chainsaw to the trunk cabin.

I keep the lines as a pin-up in my office.

Anyway, I much admire the pix of the MP sans turtles and get a real kick out of the main staysail.

Ross Faneuf
01-10-2001, 11:56 AM
Re electric drive; what goes around comes around. The US navy used turbine/electric drive in several classes of WW1 vintage battleships; as I recall, a number of the ships smashed up at Pearl Harbor still had turbine/electric drive. This was because the early days of turbine propulsion featured low-speed direct drive turbines (at a significant cost in efficiency). There was lots of fooling around trying to slow turbines down and figure out ways to get that power into the water using higher rpm. The revolutionary 'Turbinia' of 1897, which was Parsons' thumb-your-nose at the Royal Navy and a demo of the potential of turbines, was direct drive with 3 props on each of two shafts. The turbine/electric drive allowed for high speed turbines and low speed electric motors; there may have also been a single reduction gear.

This problem was eventually solved by the development of the double reduction gear in a configuration which neatly dealt with torque problems, while still transmitting up to 30K hp efficiently with a gear reduction ratio of about 100:1. This didn't happen overnight, thus all the foolery with electric drive. The Brits went with low speed turbines turning at relatively high speed.

The reciprocating steam engine era resulted in a standard max shaft rpm of 100 rpm. The Brits went up into the 300s on large vessels with low speed turbines. This number was also typical of WW2 smaller high-speed vessels like destroyers, but reduction gears brought the number back down to 100 for large vessels, where it remains (roughly) to this day; and is also typical of large diesel engined vessels. Different, obviously, for high performance or stealthy vessels, but that's a different kettle of fish.

Art Read
01-10-2001, 12:03 PM
Ian... Years ago, on the Cape, I used to see a boat that "somewhat" resembled a Marco Polo. Not sure if it was, but the rig was certainly similar. She was called ROLL-N-GO and was owned by a High School principal, I believe. Ever heard of her?

Ian McColgin
01-10-2001, 12:24 PM
Yes. Named after the song line.
She was damaged in Hurricane Bob, lovingly rebuilt next to the Orleans town dump. Sadly, her savior died recently and she's for sale in CT or RI.

Roll & Go is the most faithful to LFH's design I've seen, including turtles, no inside route from coach house forward, and enging forward of the main mast in a glorious enginstateroom. She has a shaft out the front of the engin going to a truck differential and half axel going up through the deck to a gypsey and capstan head. If the anchor's snagged, just pull the bottom up to the boat! She is strip planked. Good boat for the right person. I think Cannel Paine & Paige have her listed.

[This message has been edited by Ian McColgin (edited 01-10-2001).]

Alan D. Hyde
01-10-2001, 01:21 PM
Ian-------

What's a "turtle" in the context above?

(One of the many things I don't know.)

BTW I've always liked the MP design. Was "White Seal" a modified MP?

Regards,

Alan

Ian McColgin
01-10-2001, 01:47 PM
The turtle is a kind of arched or blistered deck at bow and stern as you see in some old time lifeboats. It enabled some headroom in the fo'c's'l and the place in the stern we won't grace with the term "aft stateroom" when we can call it the "afterberth." Neither Grana nor the boat pix above have the turtles. They do give the boat a very purposful look but don't really add seaworthiness that I can see.

I don't know White Seal.

The MP is a heeler - life at 45 degrees! And she's not real weatherly, but she's be boat you want the going gets rough. We spent a gutsey day once beating from Boston to the Cape Cod Canal against sustained 50kt winds - Couldn't sail closer than 60 degrees, tacking through 120, but despite the steep short seas we were comfortable traveling under jib, staysail, & dbl reefed fore at a through water speed of almost 7. Making our rate of advance really only a bit over 3.

Off the wind she can scream. We did Hyannis to Highland Light abeam on a beam reach - again short sail - and the D/T gave us better than 11Kt.

The lack of windward ability kills us in the one race per year we enter - It's distressing to see her little sib - a Rozanante - bound past us upwind.

Alan D. Hyde
01-10-2001, 02:11 PM
Thanks, Ian.

The camber or crown in decks is supposed to add to deck strength, and thus lessen the chance of damage by breaking waves, as well as adding to headroom.

I have what's his name's (Gerry's?) book on White Seal at home. I'll see if I can find it tonight. Interesting story, as I recall, but I haven't read it for 30 years, so I am a little unsure of much of the detail.

Alan

Chris Lasdauskas
01-11-2001, 08:27 AM
Ian,
I don't know that either picture was taken in a race (though the flying one certainly looks like it), but 'ile ola' has been used extensively in ocean racing - often in the Melbourne to Hobart which runs at the same time as the Sydney to Hobart and is considered by many to be a tougher race. Eg it has a lee shore most of the way, a couple of years ago only one boat managed to finish!

As for the 'turtles' LFH liked the extra storage they gave, true, but compared them to a lifeboat and thought they might protect the helmsman from pooping. I like them, as I said before - purposeful. Sure they reduce the room for bikini clad babes to lounge on - but in the conditions MP was intended to cope with - 'extreme seaworthiness' - I think the babes would be the last thing on my mind http://media4.hypernet.com/~dick/ubb/smile.gif

Now this particular boat is for sale (was 155,000 South Pacific Pesos, now down to 120,000 or offers), if I had the readies I'd seriously consider buying her and adding the turtledecks...

As you said Ian, differnt tastes http://media4.hypernet.com/~dick/ubb/smile.gif

Alan D. Hyde
01-11-2001, 09:25 AM
Ian-------

I owe you and Grana an apology.

It was Gerry Trobridge's 'White Seal' that I was thinking of yesterday.

She was (or is) a 36' Hanna 'Carol' ketch constructed by Trobridge after WWII and circumnavigated. He was a steelworker, and built her of steel based on his own altered plans (vetted by Hanna). She weighs 30,000 pounds.

Steve Doherty bought her from Trobridge in 1968, and was sailing her into the early 70's, but what's become of her since then, I don't know. (Tom Colvin was somewhat involved with her, and has surveyed her at least once.)

At any rate, Seven Seas Press put out a book on 'White Seal'in the early 70's (by Trobridge and Doherty) and the photo on the cover looked a little like one of the MP photos above, so that's what triggered my memory.

Many think Hanna's designs tubby and inelegant in comparison to LFH's efforts,but this little book ("Conversations with a World Voyager") does make interesting reading.

Fair winds,

Alan

[This message has been edited by Alan D. Hyde (edited 01-11-2001).]

ishmael
01-11-2001, 10:12 AM
Wouldn't a turtle deck add reserve bouancy and make the boat better able to recover from a severe knock down?

Ian McColgin
01-11-2001, 11:05 AM
Yeah, in theory.

But the Marco Polo is about impossible to knock down.

Heel to 45 in a heartbeat. At that point, there's a couple inches of rail left. I've never managed to get water over the gunnel.

Her shape integrates several features that are often seperated. She's incredibly skinny - 10'beam on a 53' waterline - but relativly shallow draft - 5'6" to 6' depending on loading which is why the snug rig, so she's not like the 'plank on edge' cutters from over where Ian the Right lives, which are very deep and really use their keels to stay upright. They are also fairly low freeboard. Grana's freeboard is pretty heafty and once she heels over those high topsides start giving her lots of form stability. That added to the effective sail area reduction caused by heeling puts an upper limit on what the wind alone can do.

Now to the waves. Most boats with lots of form stability are beamy and hard bilged. They float upright. They can carry tall high stress rigs since they have lots of bouyant beam to augment whatever keel they may have. But this also means that the boat is more affected by tilted water. Like you're sailing in a beam sea, she'll snap roll your brains out. Grana does not roll very much since she doesn't have the beam for the sea to affect.

I think about the only way you could really put her over is if you were caught beam on in a very large breaking sea. It might also be possible for you to broach in a huge breaking sea, but the hull shape discourages broaching so long as you keep your wind under control. That is, she likes a broad reach and hates a dead run. But a dead run before huge seas is dangerous in any fore&aft rigged boat anyway. Everyone else will be upside down before Grana.

Being skinny, she creates very little wake, further reducing trouble in a following sea. Much as I love Capt Pete's designs, one theory of the loss of Integrity is that she was charging off too fast and her large wake added to an overtaking wave, causing the wave to break, forcing the broaching gybe, etc.

Hanna's designs drag a lot more water around with them than a Marco Polo. On the plus side, they are capacious, very easy motion, and can pretty easily be kept to an adequately slow speed running off before a dangerous storm.

I'd not say that one or the other is superior for all sailors in all seas.

Will
01-11-2001, 12:32 PM
Talk of QEII's seaworthyness reminds me of a crossing I made in her in the fall"71" . I was an exchnge student heading for a year in England . I got to experience the joys of travel on a real ocean liner ; then we ran into a huge gale two days out from New York .

First they emptied the swimming pool and packed away the bathing beuties . This is the cruiseline equivilent of striking down the topmasts . The ship began to roll , stabalizers and all , and attendence at the lavish meals began to dwindle .

Over a period of several days the seas built to huge proportions ; well organized , immensly long crests running with the wind . Smaller wave forms were either dwarfed or smashed flat by the wind , I can't remember . The gigantic swells I will always remember . I was a little quezzy , but since childhood I'd experienced far worse sickness and discomfort rounding Point Judith in rough weather , so I could still appreciate what was going on . I even played a game of pingpong at the hieght of the storm . We struggled to keep our footing as the ball twisted its way thru impossible trajectories .

Not all the cabin accessories were stormproof , tho the ship was in no trouble . Some of the large furniture in the main saloon began rolling over . There was a pair of heavy swinging doors made of plexiglass that couldn't be fixed shut and so swung back and forth with the rolling of the boat . On the second day one of these suddenly exploded into small pebbles of plastic .

There was a bar overlooking the empty pool and the foredeck . I was there watching the storm with a small group that had not been driven to their cabins . Occassionally we would let out a communal "OH!" as the QEII took green water over her bow , and "AHH!" as she lifted and a 50 lb. particle of water from the collision thudded against the heavy plex windows .

The crossing took a day longer than planned and we were driven into Le Hauve rather than going straight to South Hampton . This is the biggest storm at sea I'll ever experience and I was safe and dry the whole time . I'll bet the modern bloatoliners stay out of the North Atlantic in fall and winter .

[This message has been edited by Will (edited 01-11-2001).]

erster
11-28-2009, 07:36 AM
With the most recent discussions on this subject, I thought that MMD and other designers may enjoy a trip back in time.

Susanne@PB&F
11-28-2009, 08:03 AM
True, Erster,
I do like our contributions in particular... And still true about 10 years later. And affects wooden fishing-boat design as well...

Lucky Luke
11-30-2009, 01:36 AM
Clever "bump", Mike.

Ten years later (do you all feel like ten years older, actually? Me: no!;)), and with all the miracles that have been expected during this decade, besides the increasing "green" fashion (I recently had to put solar panels on a project with 16,000 hp for propulsion and three 250 KVA gensets, recently.....to "look green" :p), what has really changed? Do we have "miracle" pods, accumulators, motors, solar panels or wind turbines, inverters, fuel cells, or wouldn't it still be sails and diesels that have the lion's share????

Is there, today, ONE other direction that looks realistically promising, would it be only for a few passionate ecologists?

Maybe, actually: I was recently asked my opinion about....a trireme!!!....could perhaps make use of some Guantanamo's.... :rolleyes:

Candyfloss
11-30-2009, 03:21 AM
Thanks for dredging that up Erster. Most interesting.

erster
11-30-2009, 07:12 AM
Clever "bump", Mike.

Ten years later (do you all feel like ten years older, actually? Me: no!;)), and with all the miracles that have been expected during this decade, besides the increasing "green" fashion (I recently had to put solar panels on a project with 16,000 hp for propulsion and three 250 KVA gensets, recently.....to "look green" :p), what has really changed? Do we have "miracle" pods, accumulators, motors, solar panels or wind turbines, inverters, fuel cells, or wouldn't it still be sails and diesels that have the lion's share????

Is there, today, ONE other direction that looks realistically promising, would it be only for a few passionate ecologists?

Maybe, actually: I was recently asked my opinion about....a trireme!!!....could perhaps make use of some Guantanamo's.... :rolleyes:

Old, boy how time flys. But one thing is for sure in the most recent exchanges, true death defying acts exists if you boat in hostile conditions in the wrong hull, or according to another yacht designer. ;) I think that there was some issues discussed in another thread recently. You do realize that in some parts of the world, working hulls experience conditions that some of you folks only read about in the National Geographic.




For that environment steel seems more survivable. An integrated design to live on healthily, survive 4-seasons aboard, is arare animal in the current market-place, but has been done. Studying up on what typically is conventional wisdom will not go far to get to a serious proposal and execution. Too many guild-related conventions that stand in the way. Doability, survival, ability to go coastal around ice and or over/through ice won't be found in any text-book. But such designs have been done. But not in traditional or modern wood construction. And should not be with a straight face. You might want to come back... Yes we've touched Amundsen's Gyoa (?) etc. etc. but this project you can use pleny of wood - but not on the hull or spars...

James McMullen
11-30-2009, 09:54 AM
Oooooo. . . . .a TKO by erster! What's the german for "hoist on her own petard"?

Susanne@PB&F
12-01-2009, 10:44 AM
McMullen - despite ever-broadening interests - would not know that one !

Team McMullen & Erster are behind on their Berlitz etc. studies, since they keep getting stuck for winters on end trying to fish and and do other work first next to and then promptly inside pack-ice.

Locals are debating how many more times the two should get bailed out because their (self-certificated) design- and building-prowess compells them to go fishing in hard water...

Good thing is that in this Sinking-Ship-Project, Erster has the keen eye for lines and veneer-matching, while McMullen's much advertised repair-skills will have him mix up a slurry of something (?!) in no time to force that ice into structural submission when the inevitable happens.