[MHml] horsepower & sleds

[Diane Selkirk]

Bill Gibbs wrote:
> Hmmmm...
> Hadn't thought of a jet ski.
> Aren't jets a lot less efficient than props, especially at lower speeds?
>
> Bill
>
>   
Generally yes, the cross over is about 25 knots.  Jets have smaller diameter impellers (less efficient than a big prop) but make up for it with less drag from strut/shaft/rudder.

I can't see the pitch of a jet ski impeller as being suited for pushing a big 10,000 lb boat.

Evan Gatehouse