"Authority" - how small is too small?

[modelnut]

How big should rudders and planes be to be effective?

What is the smallest (X x Y) that they can be to steer your boat?

A friend of mine didn't think much of the size of the control surfaces on some 72nd scale plans. He said that they were too small to have any "authority" in the water and that I needed to increase their size.
But I have a 72nd scale kit from Scale Shipyard's SKIPJACK and its rudders and planes are about that size. ( So I am no too worried...)

But knowledge can only be a good thing. So what is a good size for planes and rudders?

-Leelan

[JWLaRue]

I'd say to not worry.

I

I'd say to not worry.

I have both a 1/72nd and 1/96th scale Skipjack and both have accurate-to-scale dive surfaces......both work very, very nicely.

-Jeff

[modelnut]

Thanks Jeff!

I suppose it also

Thanks Jeff!

I suppose it also depends on how fast you are going to drive your boat. As this video demonstrates]http://perso.wanadoo.fr/antoine....n-1.wmv[/url]
If that boat had been handled poorly it would have done some damage to that U-boat.

-Leelan

[rpm]

On most of my models

On most of my models I scale up the rudder and planes about 10%, because the models small size is much less efficent than full scale.

[captain nemo12]

I wouldn't worry about it

I wouldn't worry about it either, just think of the rudder on the Trumpeter Kilo! The diving planes (stern) are prteey small too, but hey! If they work on the real sub, they'll probably work on the model sub too!