When Powerboats made sense

[John Bell]

Tad, would you say most powerboats today are designed from the inside out? Meaning for a given length and beam, the house designers try to maximise what's inside without much regard to how practical or attractive the outside looks. Since the most volume efficient shape is a sphere, designers these days seem to start with a sphere and stretch out a point bit on one end and a flatter bit on the other with the middle all round and pudgy in the middle.

Come to think of it, that could describe me: pointy-headed, flat footed, and soft and round in the middle... Maybe I am the target market after all!

[Kaa]

Keep in mind that today's powerboats are designed to spend most of their time motionless and when they do move, they're likely to be on a plane where the advantages of being long and slender... are not as pronounced :-)

Kaa

[TDSoren]

I love my 1967 grand banks classic. two 98 hp lehmans pushing me at a solid 8kts burning 3 gph combined. boat displaces 24,000lbs dry.

fuelmis still affordable if you're not trying to push a 42' glass condo at 15-20kts.

Tom

[Nicholas Scheuer]

The 1957 40-ft Sea Skiff you show in post #40 "is relatively well known"? First of all it is styled nothing like the two boats you show in post #55. I have seen a fair number of CC's similar to to '47 and '52 you show in #55.

[skaraborgcraft]

Uhh, that would be 550 hp total. They didn't make gas V8's at 550 hp each in 1959.

My mistake in reading the brochure,thought that sounded a little over the top. So twin engines sucking over 50 gallons an hour is far more acceptable.......

[John Bell]

Jim Wynne's CC Corvette model.. almost 40 built, and that is extremely rare for CC. Google Jim Wynne, in powerboat circles he is pretty well known.

+1. That's nice.

[tpelle]

I love those express cruisers such as the top two in post #56! I keep looking at the Rabl "Puffin", and think that would be the ideal boat for fooling around on the big river near my home.

I am amazed that these old express cruisers seemed to do OK on a 2-stroke outboard of 25 or 30 hp (or even less), but a similar-sized boat from today, made all curvy out of frozen snot, need 90 hp +.

[Figment]

I am amazed that these old express cruisers seemed to do OK on a 2-stroke outboard of 25 or 30 hp (or even less), but a similar-sized boat from today, made all curvy out of frozen snot, need 90 hp +.

It's a problem of perception and resale value.
I recently had to replace the motor on my boat. It had a 225 on it, but I just KNOW it would be absolutely fine with 200 and would probably be ok with 175hp. Thankfully, a friend made me think of resale value, and when I did a bit of homework it became obvious that the 200 would make the boat difficult to sell, and the 175 would basically be like writing "needs new motor" at the beginning of the listing. As my horizon on this boat is probably less than 5 years, I had to spring for another 225.

Why? I really don't know. Powerboats make no sense.

[chas]

"Generally speaking, as you get older, dealing with a large sailboat could be physically daunting, even impossible. That's when the single screw diesel trawler comes in handy "

Hey Hey...Watchit! Who are you callin' old. I'm planning on trading her for a sailboat...later. / Jim

[TR]

Its just a shame that everything that makes this such a fantastic looking and balanced craft, cant be reproduced much smaller without completely spoiling the style.........challenge for someone.

Scaling a particular "look" up or down is fraught with problems. People don't scale, that's the biggest problem. Big boats can be majestic, and while small boats have their charms, they are rarely majestic....so there's that major loss up front.

I did take a couple of pokes at the "Little Cassiar" concept......in the first the house is too high, in the second the windshield is not right (too modern perhaps).

[TR]

Tad, would you say most powerboats today are designed from the inside out? Meaning for a given length and beam, the house designers try to maximise what's inside without much regard to how practical or attractive the outside looks. Since the most volume efficient shape is a sphere, designers these days seem to start with a sphere and stretch out a point bit on one end and a flatter bit on the other with the middle all round and pudgy in the middle.

First off I would be a fool to characterize all designers with some blanket generalization......Every designer is different and has a different approach to his or her work. One of the real world problems I see is that much of production design is done by teams of industrial design graduates with little practical experience and tons of sales pressure. The sales guys all want to offer more features than the competition offers.....and no one says "NO!...STOP". It's very hard to turn things around and say we are going to give you less.......Hinckley did it with the original Picnic Boat. I distinctly remember the owner of the company telling me it did not matter that there was only 5'10" headroom in the foc'sl, just "make it pretty".....that proved to be a good decision. But all they can do now is pump the boat up, each model change they make it heavier, higher, wider, put in more powerful engines, and increase the cost.........

My mindset has always been to work from the outside in......create a good looking boat and then fit whatever fits into it....but of course I usually have something (in the way of an interior) in mind before I sketch the first line. Larger boats are worse, you really must be thinking about the various levels and required heights while you're working on the exterior. Open boats are simple...just make it pretty.......

[rbgarr]

The 1957 40 foot Sea Skiff always impressed me.

A childhood friend's family bought one of those when they came out and I remember (even though I was only five) spending the fifty hours cruising around with them as they broke in the engines. Then when they opened her up for the first time, boy were we thrilled! Us two boys were sitting up on the very bow with our legs hanging over the rail, leaning forward with the bow pulpit against our chests as the bow rose up and we started flying. What a rush that was. King of the world indeed!

Here's a '59 for sale now: http://www.yachtworld.com/boats/1959.../United-States

[tomtoledo]

Wow you solved my mystery boat photo!
I saw one of these in Michigan last summer and loved the lines. It didn't have a "Sea Skiff" name plate on it and the lines are so different from most Chris Craft cruisers.
This one was in great shape.

[rbgarr]

That one in your photo is the one for sale in the link. Yours for whatever you can negotiate below $35K. Hint: if it REALLY is in good shape (surveyed by a competent), start with an offer less than half and make one more bid after they scoff at your first. Let them know the second is your last and final offer. You may be thought 'unreasonable' and 'ungentlemanly' but that route has worked for me several times.

[skaraborgcraft]

That particular boat would be about 30 gallons an hour at WOT. Sea Skiffs were quite efficient on plane, because of their shape, and their light weight.

Really? 30 gallons an hour would equate to around 300hp. where did the other 250hp go? Did you mean to suggest 30g/hr at cruising speed and not w.o.t? I have no idea how well or easy these hulls were driven, only that in comparison to some,they would still be seen as fat,overweight and overpowered and not at all efficient. But im not going to compare apples with oranges,as you already say they are light and have an efficient shape. Whats the displacement of one of those?

[TR]

Finally here's the smaller boat I mentioned in post #50......

While not specifically a wooden boat she is of a type and arrangement that has been done in wood a lot. I just happen to have some hard data on this one. She is a lightly loaded semi-displacement hull very similar to a traditional Maine Lobsterboat, before they started inflating the beam. Designed in 1955 by Nick Potter the Dyer 29 is still available new built by the original manufacturer, there are over 400 of them out floating around today.

The Dyer 28 is 28'6" overall, 26' LWL, beam 9'5", draft 2'6", and displacement is 6700 pounds. With a single 160HP Perkins diesel and 1.5:1 reduction she will burn 2.7 gph at 11 knots (1600 RPM), 3.8 gph at 13.5 knots, and 5 gph at 15 knots (3 mpg!)......Maximum speed with this power is 18.3 knots at 8.4 gph and just over 2mpg.



Today this boat could be built at 5000 pounds with 4 cylinder turbocharged Yanmar (half the weight of the Perkins) and achieve even better efficency. But with the used market flooded with existing boats there is little incentive.

[skaraborgcraft]

The Dyer has nice lines,but even with a diesel its a bit of a gas hog! More money to be made in Mega-Yachts, apparently that market is still bouyant,but as you say,Tad, with so many smaller used boats on the market,you would want to have something unique or very specific to have a new boat built today. Not sure when things will turn around either.....
Maybe a VikingX in glued lap would be a boat for these times?

[rbgarr]

I saw a photo of a thirty foot lapstrake cruiser similar to the Chris Craft Express 40 shown above. it was built in the late fifties locally by Hodgdon and was powered by two fifty HP Johnson outboards. The photo shows her moving along nicely, too.

I'll try to scan and post.

[Paul Pless]

I don't have the displacement numbers on the 40 foot sea skiff, but it weighed 14,000 pounds.

Displacement and weight should be the same.

[skaraborgcraft]

I don't have the displacement numbers on the 40 foot sea skiff, but it weighed 14,000 pounds, and drew a total of 33 inches, but the hull itself probably draws about 1/2 that.

My 36 foot CC weighs 16000 pounds, batten fastened plank mahogany, twin small block chevrolets. It develops 370 horsepower total, and WOT is 28 mph. In my mileage test it uses about 27 gph at full throttle.

Interesting figures. If 1 gallon of gas equates to 10hp/hr, then your boat at WOT seems to be using 270hp, and 50hp each engine in gearbox and transmission losses is a lot. I only question the numbers because they appear not to tally. If you can stomach burning even 27gall/hr then fine......but still does not make "sense" to burn that amount of fuel,though i realise you may actually spend little time at WOT. Cheers

[dbstra]

Interesting figures. If 1 gallon of gas equates to 10hp/hr, then your boat at WOT seems to be using 270hp, and 50hp each engine in gearbox and transmission losses is a lot...

I believe Peter is referring to Imperial gallons, then his engines would be using approximately 325 HP ...

[skaraborgcraft]

I believe Peter is referring to Imperial gallons, then his engines would be using approximately 325 HP ...

OK, i agree that the different measure is more in line with a variable formula, and that piston engines are not the most efficient at converting fuel to HP,so those losses sound about right. Its still a gas hog though.....

[Breakaway]

Displacement and weight should be the same.

Not trying to be didactic, but displacement is usually the weight of the boat plus half tanks and a normal compliment of gear and crew.

Kevin

[John Bell]

Not trying to be pedantic, but displacement is usually the weight of the boat plus half tanks and a normal compliment of gear and crew.

Kevin

Fixed it for you.

JB "The Pedant"

[Breakaway]

Fixed it for you.

JB "The Pedant"

Didactic: inclined to teach or lecture others too much: a boring, didactic speaker.

Pedantic: overly concerned with minute details or formalisms, especially in teaching.



JB...we need a word that combines the two. Where's Donn?

Kevin

[TR]

Its still a gas hog though.....

That really does not matter. The reason these boats (gas hogs as you call them) are successful is they are rarely used. Average hours under way per year in the US (for pleasure boats) is something like less than 20. Thus per year the fuel cost is almost nothing compared to maintenance, insurance, and moorage. Buyers want speed, it gives you boasting rights and creates the illusion of going some place, it's expensive but if you rarely do it, whatever........

[Tom Lathrop]

[QUOTE=TR;3490973
My mindset has always been to work from the outside in......create a good looking boat and then fit whatever fits into it....but of course I usually have something (in the way of an interior) in mind before I sketch the first line. Larger boats are worse, you really must be thinking about the various levels and required heights while you're working on the exterior. Open boats are simple...just make it pretty.......[/QUOTE]

That would always be nice but often not practical. Whether a boat can be designed from inside-out or outside-in depends on the requirements it must meet. A runabout or sport boat can almost always be done outside in with aesthetics in the forefront. A large and expensive boat can usually be done the same way. The exception, and this covers many if not most boats, is when the required parameters place severe constrictions on the design freedom. An example would be a cruiser for X people and Y max length, certain accomodations, headroom, weight, cost, power, etc., etc. In these cases you have to start with the fixed parameters and then draw the aesthetics as best you can around the box.

Some very nice boats have been done within such limits though. Unfortunately most of today's ugly barges also fit this description and usually result from the overemphasis on one or more demands.

[Breakaway]

Here is one of my favorite outside the box CC designs.

Had one. Terrible--almost treacherous-- in a following sea. Too bow heavy. Had the center console version also. That boat was glitch free ( for a boat)

Kevin

[skaraborgcraft]

Peter, i dont why you assume that im thinking twin screw petrol driven launches should be economical. The title of this thread should give you a clue. It makes absolutely no sense to me that people run boats with this kind of consumption, but as you pointed out,you can afford to fill your tanks and use the boat. Specific fuel consumption is worked from engine horsepower as far as im aware. Whatever, enjoy your boat...i will stick with my Batic Sea Chaser and its excessive 5 gallons/hr . Point is and was, you still have cheap fuel,and have little regard to being economical with it. Cheers

[Peter Malcolm Jardine]

No cheers about it. You degraded one persons boating experience in favour of your own. You think your boat makes sense, which is fine. A lot of people would disagree, but since you are the sole expert on this thread, I will bow out.

[skaraborgcraft]

As far as im aware there are no rules on this forum about not voicing an opinion. My personal opinion about fuel consumption and what i think is excessive,is just that,an opinion, feel free to ignore or comment as you see fit. I dont ever recall saying i was an expert on anything, this forum is a good place to come and expand knowledge, and maybe share too. To each their own,i personally dont give a fig if you run a boat with triple 1200hp supercharged gas engines, my only point was the fuel consumption is excessive, which does not make sense TO ME! Its not my problem if my opinion bothers you, just as it doesnt bother me when a canoeist thinks i should give up my 5gall/hr gas hog and get a paddle,if we all thought the same it would be a very boring world. If it ever comes a time that this forum does not allow anyone to have an opinion,right or wrong, and a chance to voice it, i will be the first to bow out. I dont want Tads thread to degenerate into something that belongs in the bilge,so in the interest of "gas hog harmony" i shall leave you gentlemen to discuss without my alleged "degrading" of your chosen style of boating. Cheers

[Breakaway]

Whenever fuel consumption comes up, most boaters key on GPH. But without referencing that against a boat speed, its almost meaningless. A plaming powerboat with 250-hp engine might burn 10-gph at cruise RPM. That cruise speed might be 20 kts, yeilding ECONOMY of 2 nmpg. A boat burning 5 GPH and making 10 kts burns half the fuel--but still nets the same economy 2 nmpg.

Cost you the same to get from A to B in either boat.

Kevin

[TR]

Whenever fuel consumption comes up, most boaters key on GPH. But without referencing that against a boat speed, its almost meaningless. A plaming powerboat with 250-hp engine might burn 10-gph at cruise RPM. That cruise speed might be 20 kts, yeilding ECONOMY of 2 nmpg. A boat burning 5 GPH and making 10 kts burns half the fuel--but still nets the same economy 2 nmpg.

Cost you the same to get from A to B in either boat.

Kevin

That sounds reasonable Kevin but does it hold up in real life? Comparison of apples and apples is hard but in general I believe you will pay something extra for going faster. Most buyers find the extra cost worthwhile, the "it's the destination" crowd, vs the "it's the journey" people who appreciate the lower cost per hour under way.

To compare the Dyer 29 above with a current model Chris Craft 28' Launch. I'll use the CC only because I found they have some excellent performance data sheets on their website, well done CC.

The Dyer is 26' on the waterline, weighs approximately 6700 pounds, and has 160 installed HP.
The CC launch is 23' on the waterline, weights (test) 8300 pounds, and has 440 installed HP.

At 10.9 knots the Dyer gets 4.04 Nmpg.
At 23.24 knots the CC gets 2.65 Nmpg

So for a 25 mile trip the Dyer burns 6.18 usg while the CC burns 9.43 usg, we currently pay about $1.30 per liter so cost for the Dyer is $30.42 vs the CC at $46.40.

Some of this difference is in the hull forms being optimized for particular speed regimes, but not all of it. Travel time saved will cost something. The Dyer and the Chris Craft have similar amenities, taking less with you is another way to save fuel while increasing speed. Longer, lighter hulls are a possibility, but moorage logistics generally rule that out.

[Paul Pless]

So Tad, did the large Laurent Giles motoryachts ever make sense to you? They happen to be among my favourite 'lottery boats'. . .



70'
24 tons

Twin 225 HP Sabres

Engines at revs per minute shown consume in litres per hour per engine

Both @ 2000 at 11.5 kts or one at 9.7 kts consumes 22.5
Both @ 1900 at 10.5 kts or one at 9.4 kts consumes 20.0
Both @ 1800 at 9.5 kts 0r one at 8.4 kts consumes 17.5
Both @ 1600 at 8.0 kts 0r one at 7.7 kts consumes 12.5
Both @ 1400 at 7.6 kts 0r one at 7.2 kts consumes 8.0

Cruising at 10.5 knots on both engines, consumption figures from Perkins show 2000 revs consuming 45 litres per hour which would give a 466 mile range, at 9.4 knots on one engine at 1900 rpm consumption goes down to 20 litres per hour and range doubled to 940 miles.

On a recent trial, one engine at 1400 rpm achieving 7 + knots consumed approx 8 litres per hour and a range therefore of 1,750 miles.


She's currently listed @ 375,000 pounds. . .

[Breakaway]

Nice boat, Paul!

That sounds reasonable Kevin but does it hold up in real life? Comparison of apples and apples is hard but in general I believe you will pay something extra for going faster. Most buyers find the extra cost worthwhile, the "it's the destination" crowd, vs the "it's the journey" people who appreciate the lower cost per hour under way.

To compare the Dyer 29 above with a current model Chris Craft 28' Launch. I'll use the CC only because I found they have some excellent performance data sheets on their website, well done CC.

The Dyer is 26' on the waterline, weighs approximately 6700 pounds, and has 160 installed HP.
The CC launch is 23' on the waterline, weights (test) 8300 pounds, and has 440 installed HP.

At 10.9 knots the Dyer gets 4.04 Nmpg.
At 23.24 knots the CC gets 2.65 Nmpg

So for a 25 mile trip the Dyer burns 6.18 usg while the CC burns 9.43 usg, we currently pay about $1.30 per liter so cost for the Dyer is $30.42 vs the CC at $46.40.

Some of this difference is in the hull forms being optimized for particular speed regimes, but not all of it. Travel time saved will cost something. The Dyer and the Chris Craft have similar amenities, taking less with you is another way to save fuel while increasing speed. Longer, lighter hulls are a possibility, but moorage logistics generally rule that out.

Agreed on all, Tad. Especially the apples to apples with boats.

Now here's some other twists, just to consider in the name of lively discourse:

1. The Chris has twins, so there is redundancy--and additional engine maintenance--that the Dyer lacks--another cost/benefit to consider

2. AT 7 kts the Chris nets 5.65 nmpg, so if you want to go slow, you can and very efficiently ( all things being equal )

3. There is no benefit to running the Chris at 10 kts. NMPG is almost the same as at 23 kts.

Kevin

ETA: "maintenance"

[TR]

Paul,

Woodpecker, built in 1948, is a tough one. If one wanted a boat that will take you anywhere (coastwise not ocean crossing) while pretty much ignoring the weather, this would be it. Her exterior look is terrific and I really like the real mast and boom to handle a proper small boat. But her arrangement is wildly eccentric and left over from the previous century. A almost endless series of cubby-holes, each on a different level with separate deck access reminding you of a rabbit warren. It's completely different than the first boat in this thread. Originally Woodpecker had no seats on her bridge, the (professional hand) helmsman stood at the wheel while the owner observed the world from his private deck cabin below and forward of the pilot house.

Freelander, the 1959 development of Woodpecker, was the same length (70' LOA) with 2" more beam and triple 100HP Perkins engines. She would do 10 knots on one engine, 12 knots on two, and 13.65 on three........The triple configuration was chosen in this case because a lot of low speed canal use was foreseen.

[Lew Barrett]

Paul,
It's completely different than the first boat in this thread........

Which returns us to the first boat on this thread! I just adore that simple, clean Monk design. But people need to understand that inside, Monks are fairly plain and old fashioned, at least as originally built. Usually they have easy egress and entrance to the living areas from outside: you don't bang your head or have to squeeze through tiny doors, the inner passageways are usually ample (on a boat of this size) and the accommodations basic but comfortable. Not a lot of queen or king berths, and just as many heads as the boat really needed. Maybe two on a boat above fifty feet. A lot was up to the builder, but that's the general story on boats of his style above fifty feet.

I bet that the bottom profile is identical to Rita's. Nicely efficient a knot or two below hull speed. It's about Monk so I figured I needed to join in! Another excuse to post my tired old pictures and revel in what once was!


Twenty years earlier, same sheer line, same basic hull shape and layout as Patricia V. 3.6 GPH at just under 9 knots
as re-powerd, but a bit thirstier with the gas mills.



Sure, she looks a bit more like a fifties Chris than Rita does, but styles change. Beneath the skin, they are very close cousins. No tumblehome, not quite as "deco'd out" but really.......


Patricia V probably looks identical to this out of the water, minus the varnish and (superior!) choice of colors!

A very enduring design in my opinion.

[JimD]

Sunrise New York was in Maple Bay yesterday http://www.flickr.com/photos/1255929...ream/lightbox/

[pcford]

http://www.flickr.com/photos/25409219@N02/4547279834/

Syrene...Two Gardner 6L3s, 81 ft. cruising 9+ at 850 rpm. 4 gallons per hour.

Made the run from Orcas to Victoria for BC Day/Reunion of the Forestry Vessels. Return Monday was pleasant; trip over on Friday was the best ever. Perfect, stunning weather. I have some photos and videos which I shall post in due course.

[Lew Barrett]

Sunrise New York was in Maple Bay yesterday http://www.flickr.com/photos/1255929...ream/lightbox/

Wanna see what she looks like inside? Thought you'd never ask!


First. let's see her from the outside! 46 foot Dawn.

[Lew Barrett]

Hi Pat!

[pcford]

Hi Pat!

Hey Lew,
Recovering from three weeks of sanding, painting and varnishing. Syrene was fine on the Victoria. No sweeter sound than the Gardner sisters!

I have some video and photos which I which I will cut...

[Lew Barrett]

Hey Lew,
Recovering from three weeks of sanding, painting and varnishing. Syrene was fine on the Victoria. No sweeter sound than the Gardner sisters!

I have some video and photos which I which I will cut...

That's why we like 'em. The old boats, that is or vessels built with the same sort of goals in mind. I envy you your time on the water, but will get my own at the beginning of sptember. See you in Victoria. I'll be on Katie Ford.

[pcford]

That's why we like 'em. The old boats, that is or vessels built with the same sort of goals in mind. I envy you your time on the water, but will get my own at the beginning of sptember. See you in Victoria. I'll be on Katie Ford.

I think it's fair to say that it is not certain if Syrene will go to the show...probably likely but a hard decision has not been made.

[JimD]

Wanna see what she looks like inside? Thought you'd never ask!

Thanks for that, Lew. My brother and I were at Maple Bay Marina just taking an afternoon stroll and there she was. I told him if I could have any classic wooden motor yacht of any style from any time period this would be the one.

[Lew Barrett]

Thanks for that, Lew. My brother and I were at Maple Bay Marina just taking an afternoon stroll and there she was. I told him if I could have any classic wooden motor yacht of any style from any time period this would be the one.

Nice boat, with a lot of history. I won't go into all of it but will tell you she was raised from Lake Union about 20-25 or so years ago, and has been cared for by a succession of loving owners since. The latest are Russ and Dee Dee Chernoff of Vancouver (who have had her for maybe 15 years now), who in turn received her in pristine condition after a great deal of love and money had been invested. I agree; she's a sweetie!

It's funny, my (exterior) shot was taken in Brentwood Bay, but you'd swear it was the same slip as the one yours was taken in.

[Nicholas Scheuer]

Thanks for taking us back to some lovely pics of exceptional powerboats, Lew!

[skaraborgcraft]

Is that compass just for show or does it get used for navigation? I would be interested to know how the variation is effected when that radar gets fired up! Cracking boat.

Tad....Syrene...twin 6 pot gardners.....you know it makes sense!

[Lew Barrett]

Is that compass just for show or does it get used for navigation? I would be interested to know how the variation is effected when that radar gets fired up! Cracking boat.

I can't say how they navigate, but if they use it anything like the way I used mine.......
(see below)



......it is probably used to help steer a straight course in open water or for confirmation of the electronics' information. Understand, these boats are coastal cruisers, frequently used by folks who have considerable local knowledge, have "been there before" and are generally not far from shore or much out of sight of land. The challenges in such conditions come from fog and dark of night. When we got to someplace where we'd never been before, we were calling on it all; the GPS, the radar, the charts and the guide books. This area is strewn with coastline, hundreds of islands, inlets, channels and the like. Once you are fully instrumented, you (I) tend to use the electronics first and the rest for confirmation. Not the other way around. Like a pilot flying in cloud, one learns to trust the instruments.

Yes, it's a pretty binnacle! How they use it I don't know, but I used my compass a lot less after getting the radar and chart plotter. Thing is, I do know how. I think that's important. But the electronics really made it a different game for me. You don't see "my" instruments because they were all mounted overhead. I liked the cleaner look of the dash that way, and my instruments are later vintage than Sunrise New York's, so I could do that without a lot of interference. I never noticed much difference in the compass' performance after installation of radar, but after re-powering it needed to be re-swung. Badly!

[JimD]

And if I were shopping for a new design it would probably be one of Tad's, such as...





Of course at the moment that's too big an if to contemplate but you never know when a suitcase full of money is going to fall out of the sky.