Surface speed was Re: [PSUBS-MAILIST] Underwater pod on surface vessel

[MerlinSub@t-online.de (Carsten Standfuß)]

For the friends of the metric units: 

Hull speed (mono hull) on surface in knots = 
2,43 x square root of the length of the ship in the waterline in meter. 

example : 

CSSX LOA : Length over all 	16,01 m (52,5 foot) 
CSSX LWL : Length at waterline 	15,80 m (51,8 foot)

2,43 x square root of 15,80 m = 9,66 knots. 

With a little more power before xy curve get to high on 
the angle : 10 knots should be possible. 

Unfortunatly tank test shows that this kind of hull 
start to dive into there own bow wave at a speed of 8-9 knots
depents on the freeboard and trim angle. 
This will increase the power consumption and lower 
the surface stability. 

I think the right formular in feet should be : 
1,34 x LWL^1/2  bez. 1,34 x square root LWL. 

see you - Carsten

"Sean T. Stevenson" schrieb:
> 
> I think you missed a square root term:  Surface vessel theoretical hull speed = (1.34 x LWL)^1/2
> 
> -Sean