PerryH
Veteran Member
Hey folks,
New to the forum and new to trawlers.
I'm looking at a 1977 marine trader 40 double cabin. This is our first time in the market for a "livaboard size vessel".
This boat had a survey in 2014. Clearly on page 6 the survey lists the boat hull type to be semi displacement.
It has a single Lehman 120.
Am I missing something here? 30,000 pounds with 120 ponies...This boat seems like it should be a full displacement hull. Right?
My basic understanding of semi vs full is this:
On a semi the engine power is divided both between forward propulsion and lifting the bow. Semi = slightly faster cruising speed at the cost of significantly worse fuel consumption.
On a full displacement 100% of the engine power is spent on forward propulsion. Full = slower speeds but it's the most fuel efficient vessel under power aside from a sailboat.
I'm sure my understanding is elementary so any and all help is greatly appreciated.
Thanks,
Perry
New to the forum and new to trawlers.
I'm looking at a 1977 marine trader 40 double cabin. This is our first time in the market for a "livaboard size vessel".
This boat had a survey in 2014. Clearly on page 6 the survey lists the boat hull type to be semi displacement.
It has a single Lehman 120.
Am I missing something here? 30,000 pounds with 120 ponies...This boat seems like it should be a full displacement hull. Right?
My basic understanding of semi vs full is this:
On a semi the engine power is divided both between forward propulsion and lifting the bow. Semi = slightly faster cruising speed at the cost of significantly worse fuel consumption.
On a full displacement 100% of the engine power is spent on forward propulsion. Full = slower speeds but it's the most fuel efficient vessel under power aside from a sailboat.
I'm sure my understanding is elementary so any and all help is greatly appreciated.
Thanks,
Perry
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