Bollard Pull Tables.

[TheBoatman]

Does anyone know where I might find comparrison tables for Hp to bollard pull for in and outboard engines?

I.e. 50 hp inboard against same Hp for outboards.

Peter.

 

[Mirelle]

Well, I know how to cheat...

Sheer hard.

Really, really, hard - you want to get about a 20 degree list on.

Not really approved of since the offshore industry developed and the Class Societies took up issuing bollard pull certificates.

Back to the subject, there is a nice discussion of outboard bollard pull figures on

John Williams's Saving Old Seagulls website

 

[trev]

This would not be a direct relation to horsepower, but would depend upon propeller pitch, revs, size of prop etc. A prop used for towing is adjusted for max torque as opposed to a prop for speed.
As a rough guide in the offshore industry we use 1.1 x the BHP divided by 100. but we're dealing in thousands of BHP.

 

[graham]

I remember seeing a comparison test of 8-10hp outboard engines as auxillaries for a long keel Invictor or something similar.

Fairly sure it was in Sailing Today but not which issue.

Part of the test was a bollard pull comparison .

Sorry ,not much help I know ,maybe someone else still has the mag?

 

[fireball]

Yup - it was ST ... I have the report somewhere ..... it was testing outboards for small cruisers - don't think they compaired to an inboard though....