Plywood limits ?
By ultralight trawler, I wanted to mean light powerboat designed to be used
in displacement mode. speed 1.34 sqrt(lwl). planning speed or even semi
planning not intended.
A GB 49 is 60000#. a nordhavn 43 is 53000#.
The GB42 is 34000# , but with 2 * 430 hp, it is not intended to be used in
displacement mode. The minimum power available is still 2 * 210 hp.
The GlenL boats (argosy klondike) are in the same weight range. But they are
semi planning boats too. (cruising speed 12 kts).
So I would call a displacement mode boat 42 -48 # lenth weighting under
30000# boat as light.
Have seens the photos of the 48 duck built in wood from G Bhueler.
Its beyond my (and my father) possibilities. Financial, technical , time ...
It a boat in the 60 000 # range.
The pilgrim 44, 10 000 # on the other side, is rather simplistic and light
with its outboard engine. A scaled up canoe.
More interesting are kasten marine designs. But alas, the designer is
specialised in metal (steel ou alu).
A boat like the coast runner 48 ocean express 49 look more like what I want.
But they are both semi planning aluminum boats, and only at the preliminary
design stage today.
Also there are things I don't understand. M Kasten give 40 hp to reach 8 kts
on a 46.75 lwl, 32000# boat. G Bhueler claims 21 hp for 8.1 kts,with 46.3
lwl and 57000 # disp. Both single hard chine.
NB english is not my natural langage.
Thanks.
"Jacques Mertens" a écrit dans le message news:
...
Is ultralight trawler not a contradiction?
The boats you list and that some propose are all heavy as a trawler shoudl
be.
How about a large dory? D. Gerr and G. Bhueler have designed some nice
ones.
Reuel Parker too.
That would be much easier to build, less expensive, lighter. A 50' dory
would move nicely with a 100 HP engine.
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