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Old 05-23-2020, 07:38 PM   #10
stevemitchell
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City: Seattle
Vessel Name: Aruna
Vessel Model: Kristen Yachts 50 Pilot House
Join Date: Sep 2018
Posts: 541
Quote:
Originally Posted by Rufus View Post
The Powerboat Directory is accurate. Ours has twin 250s....top speed 17-18 kts. It gets over the "hump"/bow wave at 10-11 knots and is solidly on "semi-plane" at 12 knots. Our boat has a fairly heavy center console dingy hanging on a transom mounted Nick Jackson style davit, so it takes some trim tab to get it "out of the hole". Without the dink it pops right up. Fifteen knots cruise is about 140 HP per engine....fuel burn 7.4 GPH per engine. Roughly 1NMPG. For better fuel efficiency, I cruise at 8-9 kts and get 1.8-1.9 NMPG.



Depending on who you ask, the hull is semi planing/displacement or modified planing. In any case it's full in the forward half and has a keel...so it's a bit more draggy at higher speeds, but quite efficient at slow speed and either side of the hump speed. A full planing hull like a Carver would likely do slightly better at 15 and above. I've cruised our boat at 15 with no issues.



The 315 Cummins would be loafing at 15 kts.



Attachment 102912


What engines do you have? Maybe I need to be running faster because my fuel economy is not that good around 12-13 so maybe I should be running at 15....
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50 Kristen Yachts Pilothouse
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