Nutty, motor, steering under tow

[G4YVM]

Reading a few books makes it plain that a motor boat might not steer well under tow, certainly not as well as a genuine butty might.

 

Did / do butties have bigger rudder blades?

 

David

[alan_fincher]

Reading a few books makes it plain that a motor boat might not steer well under tow, certainly not as well as a genuine butty might.

 

Did / do butties have bigger rudder blades?

 

David

Generally yes.

 

A motor steers largely by deflecting the wash from the propeller, a butty only by deflecting the water passing over it as it moves.

 

Maybe not always fully appreciated are.....

 

1) An unladen butty has far less "rudder" in the water than a laden one.

2) Most "motorisations" of buttys, whether by a propeller through the stern post, or an hydraulic motor in the rudder itself, lose a lot of the original rudder area. Such boats, if then put under tow, will have less steerage than they did before motorisation.

 

Empty buttys were generally towed "close coupled" to the motor on "cross straps", and generally then needed very little steering. It was not unusual to see them towed in this manner with no steerer.

 

EDITED: to remove some of the more obvious spelling and grammar blunders!

Edited May 21, 2012 by alan_fincher

[carlt]

Reading a few books makes it plain that a motor boat might not steer well under tow, certainly not as well as a genuine butty might.

 

Did / do butties have bigger rudder blades?

 

David

Yes they do but, unloaded, they have no more useful rudder area than a motor.

 

The only time I had trouble steering a towed a motor was when we were towing Unspoilt by Progress from Cropredy to Napton for repairs.

 

The rudder had been knocked off the skeg when the owner cilled it in a lock so it was a pig to steer.

[mykaskin]

An empty butty while it might not have much rudder in the water is light so has enough in to steer. The lines of the boat are also fairly fine so get the water smoothly to the rudder.

 

A motor boat towed will have a small amount of rudder in comparison to the weight of the boat, and may not have such fine lines - and the prop will also disturb the water before reaching the rudder.

 

However, after towing a modern boat on the Paddington arm on just tiller strings (to hold the rudder straight) and the bow wasn't high enough to cross the strap on - I was fairly surprised how well it followed Victoria. Had to take it steady across corners so it didn't get a swing on. I also wouldn't try it on a narrower canal with many moored boats!

 

I have also towed another modern boat and that worked fairly well, but had people on the stern steering and when it got sucked towards moored boats they could fend off.

 

Cheers,

 

Mike

[G4YVM]

Thanks!

D