Do trawlers roll a lot?

[Delfin]

OK - to summarize - It appears the general consensus (with exceptions) is the a well designed hard chined planing hull is more stable at rest than a soft chined displacement hull. Also - in average-good conditions, the same planing hull has less roll traveling at speed than a displacement hull traveling at 6-8 knots.
The reverse is true when the weather turns really ugly and the planing hull must slow to displacement speed. In this situation, a well designed displacement hull is much better equipped to ride out the storm, whereas the planing hull operator should read the changing weather and use its speed to get to safe water.
Have I got this right?

Yes.

 

[Nomad Willy]

Art,
Where did you get the impression Willards were made of wood? Nary a one. They are all plastic like your Tolly. And what on earth is a "Twatler"? That's right Art you can call your mighty fine Tollycraft cruiser whatever you wish but if you don't like cruisers why do you have one. If I were you I'd probably lean toward being proud of what my boat is. By the way there WAS a Tollycraft that tried a little bit to be a trawler. An earlier plywood boat that had her wheelhouse way fwd. There was one in LaConner some time ago. I really liked that boat (38' I think) but your "boat" is much better looking. But if you have a picture of one of those Trawlycraft cruisers I'd like another look.

Auscan, Deflin and Art,
So if I read Chapman's enough I could round the Horn w my 26' 1966 plywood Sabrecraft light cruiser. I disagree. I think, generally speaking that full disp boats are more or much more seaworthy than planing boats. Planing boats MUST be light and light is at a big disadvantage in really big stuff. The shape of planing boats at both ends is either not good or bad for being on big waves. A light structure is light and a planing boat needs flat surfaces to plane well and flat surfaces are weak. And a boat using it's speed to run for shelter is showing all the world it's seaworthyness is in question. A seaworthy boat will have a relatively rounded hull shape and greater weight with it's greater strength.

 

[Art]

"Also - in average-good conditions, the same planing hull has less roll traveling at speed than a displacement hull traveling at 6-8 knots."

The problem is All boats roll , the shape of the hull will determine weather the boat is a bard bucket.

Roll which is soft (tho perhaps further ) when it checks and reverses direction is the easiest to live with.

A box bottom or hard chines is great at the slip , but underway the corners stop the roll much harder with a sharp quick motion.

BARF, BARF, BARF,

A really skinney hard chined boat might do this less , but few are that skinny.

YRMV

Fred

Guess it’s because I like the feel of the sharp, responsive hard chine planning hull’s immediate return actions to my piloting commands while I Capt a boat (especially a good design well powered twin screw craft)... while in ocean waves, confused inlet waters or inland water ways from huge wakes or stormy winds. And, cause I was blessed with real good equilibrium tween my ears so the word Barf never has come to mind or fruition during any boating circumstance. I’ve piloted D hull boats; at or below hull speed I found their roll a PITA for any ongoing duration as well as making it more difficult to stay on heading in some sea conditions. Now don’t get me wrong... D, SD/SP, and P hull designs all have their high and low points for working with water conditions... and D’s surely offer the most economical capabilities... in the long run. However, I prefer the overall feel of hard chine bottom twin screw boats with rounded transom, slicing prow, and substantial upper hull flare that can be cruised quite economically at hull speed with one screw operating at a time... yet provide opportunity to fire up her twins and plane out for smoother ride and more mileage covered, with potential to run for minutes or hours at near WOT - - > to move like hell and get out of the way whenever necessary. Our Tolly gets approx 2.75 to 3 nmpg doing 6 to 6.5 knots on one screw (7.53 k is calced hull speed)... 2 nmpg on twins at hull speed... 1 nmpg at 16 k to 17 k twin screw plane... and, OMG – NO nmpg at 20 to 21 knots; WOT 22 to 23 k. All these figures are +/- depending on how loaded our Tolly may be.

Using 32’ water line length; for a thumbnail of annual miles traveled/fuel cost comparisons:

Single screw D hull averages 3.5 to 4 nmpg operated at its hull’s cruise speed of approx 7.5 knots. Twin screw P hull averages 2 to 2.25 nmpg when intelligently operated at its various cruse speeds (let’s say an average of 10 knots). Boats are each operated 300 hours per year. Therefore: D hull travels approx 2,250 miles / P hull travels approx 3,000 miles - - > Figured on the best fuel mileage calcs – D hull uses 750 gals per year / P hull uses 1,333 gals per year - - > that means (at avg fuel cost of $4.50) that D hull costs $3,375 in fuel / P hull costs $5,999 in fuel - - > difference is $2,624 annual dollars – divided by 52 weeks = $50 per week extra fuel cost to own and enjoy the capabilities of a planing hull. Most boat owners can handle that. Also to look at this difference is in another light - - > if instead of the 3,000 mile travel figure used in these calcs for P hull, we reduced P hull to the miles traveled at 2,250 miles of the D hull (notably less hours for P hull to go same distance), and took the 750 mile reduction x 2.25 nmpg at $4.50 per gal cost then P hull annual fuel cost is reduced by $1,350. In that light it means P hull added annual fuel cost over D hull was only $1,274 which = $25 more cost per week to fuel a P hull in comparison to a D hull – I’ll gladly spend that $25 per week to get there quicker, experience better ride, and spend more time on the hook/dock-berth/mooring with a Planing Hull!


YRMV!!! Art :lol:

 

[mahal]

Am I correct in thinking that if you want a serious passagemaker you buy a boat with a displacement hull and if you want a boat for just cruising around locally you pick any hull type that turns you on?

There has to be a very good reason why passagemakers like Deltas, Nordhavns, Watsons and others have FD hulls.

 

[Art]

Art,
Where did you get the impression Willards were made of wood? Nary a one. They are all plastic like your Tolly. And what on earth is a "Twatler"? That's right Art you can call your mighty fine Tollycraft cruiser whatever you wish but if you don't like cruisers why do you have one. If I were you I'd probably lean toward being proud of what my boat is. By the way there WAS a Tollycraft that tried a little bit to be a trawler. An earlier plywood boat that had her wheelhouse way fwd. There was one in LaConner some time ago. I really liked that boat (38' I think) but your "boat" is much better looking. But if you have a picture of one of those Trawlycraft cruisers I'd like another look.

Auscan, Deflin and Art,
So if I read Chapman's enough I could round the Horn w my 26' 1966 plywood Sabrecraft light cruiser. I disagree. I think, generally speaking that full disp boats are more or much more seaworthy than planing boats. Planing boats MUST be light and light is at a big disadvantage in really big stuff. The shape of planing boats at both ends is either not good or bad for being on big waves. A light structure is light and a planing boat needs flat surfaces to plane well and flat surfaces are weak. And a boat using it's speed to run for shelter is showing all the world it's seaworthyness is in question. A seaworthy boat will have a relatively rounded hull shape and greater weight with it's greater strength.

Eric - to your items bolded above:

Don't remember saying Willards are wood?? Matter o' fact I did not know their build-out materials so I would not have conjectured - I think?

I have clear close-up pict of Tolly you mention, but can’t get it to downsize to attach here... PM me your email and I’ll send you the pict. Also visit http://www.tolly-classified.com/class3.html for more descriptions of many models Tollycraft. Punch up the 1977 and 1978 pages off that page to see the 37’ so called Trawler and 37’ so called Long Range Cruiser, respectively. That model was discontinued from lack sales of due to lack of interest by Captains as well as general boat owners.

Our low center of gravity Tolly 34' weighs 17,000 lbs dry and approx 21,000 fully loaded - you feel that's light?? Well... maybe you feel that way because Tolly does not need 1,000's of extra pounds ballast in order for it to perform!

Although you have a nice D hull boat – May I suggest getting a nice P hull next time. Live life!!! Well designed P hull boating is fun too!

 

[Art]

Am I correct in thinking that if you want a serious passagemaker you buy a boat with a displacement hull and if you want a boat for just cruising around locally you pick any hull type that turns you on?

There has to be a very good reason why passagemakers like Deltas, Nordhavns, Watsons and others have FD hulls.

Mahal - Economy for long distance big/long/heavy passage makers... it seems a D hull can't be beat! Unless, the owner has bottomless pockets that is... then economy is not even in their range of care! Regarding overall sea worthiness of a fine designed, well built craft, the jury is "always" out on P or D hulls. It depends on a Captain's preference. Also, after a certain length the only wise design is D hull, i.e. longer they are greater their hull speed is! - Art

 

[Delfin]

Am I correct in thinking that if you want a serious passagemaker you buy a boat with a displacement hull and if you want a boat for just cruising around locally you pick any hull type that turns you on?

There has to be a very good reason why passagemakers like Deltas, Nordhavns, Watsons and others have FD hulls.

That would be the way I would look at it. One factor is that a full displacement hull has the center of gravity very low compared to a planing or semi displacement hull. This takes on some importance when the waves get to, oh, 30 footers.

Another factor is that whatever kind of stabilization you have, it will be more effective on a tender full displacement hull than a stiff semi displacement or planing hull, also a factor to consider on two week long passages. Tenderness translates to a greater tendency to roll without stabilization, but less force required to correct roll with stabilization.

If your cruising grounds are all behind islands, or only involve short hops in the blue, then a stiffer hull may give more pleasure than an unstabilized full displacement hull. If stabilized, however, my preference is always the fd hull simply because the motion through the water (wherever that water is) will always be more comfortable that the alternatives.

 

[Marin]

That's right Marin.
We're all (most at least) heavy cruisers and that's what they (trawlers) were called before someone came up w the silly idea of calling ice cream boats trawlers.

As I've related before, American Marine never used the term "trawler" to describe their Grand Banks line of boats. In their ads and literature they simply referred to them as "diesel cruisers.". Which is what I call all boats of this type. The faster planing or semi-planing boats like Tollycrafts, Uniflites, and any other boat with the set back, raked-windowed main cabin I call a "cabin cruiser" which was the original name of this type of production boat back in the 1950s or whenever.

As to stabilizers I agree with Psneeld's basic premise that for most coastal cruising they probably aren't needed unless one is particularly bothered by rolling motion. We've never felt the need for stabilizers even though a GB has the quick snap-back roll typical of this type of hull.

 

[jeffnick]

My trawler was a roller. My small outboards got tossed terribly in any kind of wake. Now I'm running a 28' tri-hull houseboat that only goes up and down...very little roll or pitch. Is it 'seaworthy'? Probably not, and I don't intend to find out. I have no plans for offshore passages or open water runs... My point is that if you want a looper type boat, you can have one that will not rough you up from a wake or chop and if you need to wait out the weather, and you will, you'll be doing it on a relatively stable platform.

This is a track from an overnight on the hook on Lake Powell. NOAA reported winds over 30. For us it was a peaceful night.

Pic of tri-hull on trailer.

 

[Moonstruck]

Gosh, next thing you know Eric will be saying that I don't have a trawler!!

Yes, trawler style boats as any unstabilized boat will roll at displacement speeds or at rest. Dynamic stability is a very real thing. If you don't believe it, come ride with me at planing speeds. Then slow down to displacement speeds. My deep V in a beam sea will roll like a round bottomed boat.

You will get used to the characteristics of your boat, and drive it for the best comfort in different situations. Just don't tempt fate. Be reasonable and take precautions.

 

[Baggiolini]

Spent last weekend at Capitola, a slightly protected anchorage in Central California. I was super happy with my $130 investment in Rocker Stoppers, the orange plastic cones. Five on each side with a 6lb weight on the bottom. It would have been a rough weekend without them.

 

[sunchaser]

So this thread has degenerated into those few of us who enjoy and use(stabilized and/or ballasted) rough water designed trawlers fending off those in the majority who enjoy calmer waters designed vessels. I've owned 3 Searays if that counts for anything.

 

[Art]

Gosh, next thing you know Eric will be saying that I don't have a trawler!!

Don - Let's call yours a Super Charged Trawler!! Mine is a medium charged one... Yea, that the ticket! lmao! - Art :lol:

 

[Art]

So this thread has degenerated into those few of us who enjoy and use(stabilized and/or ballasted) rough water designed trawlers fending off those in the majority who enjoy calmer waters designed vessels. I've owned 3 Searays if that counts for anything.

Sun -Counts for fun, understanding and your post # 1598!

 

[Nomad Willy]

Don wrote:

"Gosh, next thing you know Eric will be saying that I don't have a trawler!!"

No Don because you don't talk about halving a trawler.
And when/if you do it's so subtle I don't notice it.
Your Sabre is not a trawler but it's more of a trawler than Art's Tolly. John Baker's Mainship isn't a trawler either (it's an express cruiser) nor are a lot of other boats on the forum. But this is just my opinion. And all the opinions here are quite different. To me a Fathom 40 (sold as a trawler (I believe)) isn't a trawler and many of the recent "trawlers that look like a trawler above the WL but aren't below like a Camano Troll and a Ranger Tug. Most or even all of these owners think or want to think they have trawlers. Trawlers have a problem in that they have attached to their image a macho masculine old salt image that is very real. Art dosn't like it when I say he dosn't have a trawler because I've attacked his vanity, boating guruness and masculinity. And they are obviously very important to him as he hangs on to his image so tenaciously it's hard to believe.
But that's just my opinion and if it's going to be a problem perhaps we should have a series of polls and determine a democratic group definition of TRAWLER ........ No we'd probably fight over the results. I've made my point and after halving the opportunity to express myself (something I like to do) I'll not criticize Art again for claiming he has a trawler.

 

[psneeld]

I think many ought to spend more time at the railwaiys looking instead of dreaming...a lot of full displacement trawlers, clammers, netters, longliners...etc...etc have hard chines and other than being a bit fuller amidships, they look a lot like many of the boats many of us own. Many of us real boat owners see in our REAL LIFE performance curves that at slower speeds MOST hull shapes perform very closely...planing, semi and full displacement when all run in the displacement mode.

 

[Art]

Art dosn't like it when I say he dosn't have a trawler because I've attacked his vanity, boating guruness and masculinity. And they are obviously very important to him as he hangs on to his image so tenaciously it's hard to believe.

I've made my point and after halving the opportunity to express myself (something I like to do) I'll not criticize Art again for claiming he has a trawler.

Eric worry not - I really don't care what my boat "type" may be called... it is you who cares what you feel different boats may/should/could be called. In the pleasure craft arena, in my opinion, a boat is a boat is a boat! Growing up in New England, nearly always aboard or around boats and boat yards... as well as commercial fishing trawlers in 50's/60's,70's... I always thought it strange when the word trawler became affixed to pleasure craft. Enjoy your trawler... I'll enjoy my Tollycraft boat! Cheers, Art

 

[Budds Outlet]

If I go slow enough and put a bunch of weight in the bilge can I call my Sea
Ray a trawler? I carry a Zodiac on the swim step. What else should I do to get the respect due a real trawler captain.

And further, do I understand it correctly that even after I buy one of those big Tollycraft that I won't be accepted as a trawler captain? Oh the humanity!

 

[CPseudonym]

What else should I do to get the respect due a real trawler captain.

I have this vision in my head of your boat with a mast and small stabilizing sail on it

 

[Art]

Ain't words and the perceived/intended meanings thereof FUN!!! :lol:

 

[Marin]

There has to be a very good reason why passagemakers like Deltas, Nordhavns, Watsons and others have FD hulls.

Well designed displacement hulls are easily driven which means you don't need gobs of power which you can't use anyway. Small-ish engines burn less fuel which means the typical single-engine Nordhavn has a great whacking range to it which is what you want if you're going to cross a big chunk of ocean.

And I don't believe there is a rule that says displacement hulls have to have round bottoms and chines. I've posted these shots before, which I did not take, but it shows one of the sampans or aku boats that were built locally in Hawaii in the later 1940s and early 50s for the tuna (aku) fishery there. These relatively narrow boats incorporated flat albeit curved bottom sections, hard chines, and even gunwale " hull bulges" (my term) to provide roll stability in the often very rough waters these boats fished in, like the infamous Molokai Channel. The "hull bulge" is obvious in the second shot and was quite effective as these boats were often rolled to their gunwales in the windy swells and waves around the islands.

But displacement boats they were, most of them powered by a single GMC 6-71. Watching them knife through the swells and waves like destroyers was a beautiful thing indeed. I filmed on a few of these boats in the 1970s and while they certainly rolled around-- hell, even sperm whales roll around in the Molokai Channel-- it was amazingly easy to keep one's balance and footing while on board. I have no idea who designed the hull-- all the aku boats had the same basic lines above and below the waterline-- but whoever it was, he understood the nature of the open ocean the boats were going to work in and how to design a hull to effectively meet the challenge.

The boats were almost exclusively crewed by Japanese Americans and I was told the word "sampan" is the Japanese term for carvel or smooth-sided planking, as opposed to lapstrake.

The bottom line being that a displacement hull does not automatically have to mean super-rolly.

 

[Delfin]

And I don't believe there is a rule that says displacement hulls have to have round bottoms and chines.

And if they don't have round bottoms and/or hard chines, what do they have??

By the way, was it you we motored next to out of Peavine Pass a couple of weeks ago? My wife took a picture and I just saw the La Perouse on the stern, which must be you. You should have waved! I would have waved back.....

La Perouse looks good in the pic....

 

[Nomad Willy]

Thank's Marin,
There are numerous Kayaks w that basic hard chine shape. The chine and it's characteristics are one of the easiest elements of design to get lost in. Many for example think the soft chine on a lobster boat makes it a disp boat ... not at all. Chine lore is very misleading. And what seems obvious frequently isn't.

Budds Outlet,
Be pretty hard to fool anybody w a Sea Ray. But who cares. I'd like to go for a ride w you at 30 some knots ... would be kinda thrilling to me but a ride on my wallowing Willy probably wouldn't appeal to you. Kinda dull prolly.

"get the respect due a real trawler captain." That's where that mystique about manliness and saltyness comes from. It could be that the Hawaii 5"O" and other fast lane dudes have as much boat handling and seamanship experience and knowledge as trawler skippers. I hear them chat on BD.net and lots of them are very knowledgeable builders, skippers and designers .. sometimes all put together.
One chap (fm UK) had a wonderful thread about the evolution of a race boat w great pics of the construction and then great shots of the finally completed boat at 70 knots (or whatever). It was a tripple step deep deep V.

So why does the trawler guy get so much respect. Perhaps I think deep down it's not due trawlermen anymore than other boaters. Of course the same guys that were going to Alaska in the 50s and early 60s in Chris Crafts are going today in GBs, CHBs, MTs and NTs. And perhaps I'm all wet. Maybe we DO deserve all that respect ... but not the boats. It's the skipper that's in line for respect. If he walks the walk.

 

[Marin]

And if they don't have round bottoms and/or hard chines, what do they have??

I probably more clearly should have said "...if they don't have round bottoms and/or round/soft chines.".

In other words, a displacement boat can have a bottom consisting of flat albeit curved surfaces and/or hard chines, characteristics a lot of people associate only with semi-planing or planing hulls. The aku boat in the photos I attached being an example of this.

 

[Marin]

Eric--- In my opinion this whole business of calling a recreational boat a " trawler" started as nothing more than a marketing ploy to attach the image of a rugged, seaworthy working boat to a recreational boat that wasn't any of those things. The car people do the same thing--- witness the H2 "Hummer" which is nothing more than a Chevy Tahoe with a Humvee knock-off body on it. Or Lee Iacocca's original "Mustang" which was nothing more than a Ford Falcon platform with a sporty 2-door body bolted on top.

As the CEO of an airline told me a number of years ago, "Perception is fifty percent of everything today.". These days, it's probably more like eighty percent. So we get toy boats that the manufacturers call "trawlers" simply to make buyers feel like they're buying a piece of rugged, maritime heritage.

Where in fact the only similarity between real trawlers and the vast majority of toy boat trawlers is that neither one is a submarine.

 

[Nomad Willy]

Art,
Re post #33
You actually think people buy a full disp boat just to save fuel?
They actually buy them to have a better boat. All boats were FD before the engine came along and then there were mutations that descended to accommodate the engines. There are a few of them left.

 

[markpierce]

Naval architect George Buehler thinks a better term/inspiration is "troller" for our recreational, heavy-displacement "trawlers."

concept

 

[Art]

Art,
Re post #33
You actually think people buy a full disp boat just to save fuel?
They actually buy them to have a better boat. All boats were FD before the engine came along and then there were mutations that descended to accommodate the engines. There are a few of them left.

Eric

Time to get serious now - lol ... i.e. there is not much too serious about pleasure craft that we on TF own and make love to. "Pleasure" being the operative word. Trawlers (that is real fishing/working trawlers - not our toy boats that some like to call trawlers) had little to do with pleasure, except maybe a good payday for the working crew after weeks out trawling while enjoying the cash $$$ results from a good catch.

To say FD is a better boat just because it is FD strikes of... well... lack of understanding about and/or experience with other hull types such as SD/SP and FP.

Reasons the boats were all FD before engines became available is two reasons 1. Why bother to try and improve hull designs to a planing design since no power to reach plane previously existed. And, 2. Hull design technology had yet developed to the point of understanding water lift dynamics well enough to create corectly formed planing hulls. It took engine power (not wind power) to push planning hull design technology onto higher levels of understanding.

To say, as you did: "All boats were FD before the engine came along and then there were mutations that descended to accommodate the engines." ... is simply 50% incorrect. As you correctly say, all boats were FD before engines and that planing hulls are a mutation from FD's. However, instead of as you say P hulls are a descending mutation, Full Planing and SD/SP hull designs are ascending mutations that have attained improved levels of hull designs from simply having FD hulls that had been available for 1000’s of years.

As I've mentioned before, a well designed good-build boat of FD, SD/SP, or FP all have their own attributes. In any sea conditions or other boat control situations the buck stops in the operating Captain’s hands. Smart/knowledgeable Captains can make most boat rides a good one... inept/inexperienced Captains can make nearly any ride turn into a nightmare.

I like well built boats comprised of FD, SD/SP and FP hull designs. I most enjoy operating and staying aboard well built, comfortably laid out, twin screw, FP boats. That is why I own a super sturdy and durable 1977 34’ Tollycraft Tri Cabin!

Enjoy your FD Willard and I’ll enjoy my FP Tolly!!

Art

 

[Art]

Naval architect George Buehler thinks a better term/inspiration is "troller" for our recreational, heavy-displacement "trawlers."

concept

Damn nice attached page Mark... I got your drift! Great looking classic Troller boat at page end! Thanks, Art

 

[FF]

Very few "trawlers" carry enough power to plane well.

"Well" being going fast enough that the fuel consumption per mile actually goes down with increased speed. SL 3+

At semi displacement speeds SL under 3 , there is little difference in weather a boat is round bottoms or has flats aft .

Mostly weight is the prime concern , hull shape (unless a plaining disaster like a canoe or double ended) doesn't make much difference.

The commuters of the 20's and 30's had mostly rounded bottoms and were fast and smooth riding for their times.Heavy engines + heavy hull weight was their biggest handy cap!

FF