in regards to power there is something I found at the Dutch Barge Association
Following up from previous interesting threads, Ive looked at the size of engine recommended for 4 hypothetical vessels to achieve various desired top speeds, using Volvo's Engine Configuration web page http://www.volvopenta.com/volvopenta...figurator.aspx
Ive rearranged things to show what maximum speeds (in knots) certain engines will propel these 4 vessels.
I chose vessels of the same weight but different waterline lengths and of the same length but different displacement:
Installed HP - 20 40 75 110 180 225 260
Vessel A: 14 m 22 tons 6.1 7.3 8.4 9.1 10.3 10.9
Vessel B: 19 m 22 tons 7.1 8.4 9.6 10.5 11.8 12.5 13.1
Vessel C: 19 m 50 tons 5.8 6.9 8.0 8.8 9.8 10.2 10.6
Vessel D: 27 m 50 tons 6.8 8.1 9.5 10.3 11.5 12.1 12.5
These are presumably speeds in ideal conditions smooth deep water, good antifouling on a clean bottom, a slippery hull shape, etc. The main things of interest:
· At slow speeds all these vessels are incredibly easily propelled 20 hp is enough.
· An increase in displacement slows you down as you would expect
· An increase in length speeds you up by quiet a big margin!
· The big vessel (D) of twice the length and twice the weight of the small one (A), requires less power to maintain any given speed. At 10.3 knots, the big vessel needs just 110 hp, whereas the tiddler requires 180 hp.
I am ready to buy my fist boat in he US and am amazed that there are so few steel boats available. Also most boats seem so much 'overpowered'
After having been on boats who are over 100 years old I like to see how durable fiberglass is