rudder skin and elevator skin cracking

[Ronald Sutton]

By fluting a 3/4 inch curve the rudder and elevator stiffeners, the skin will have a slight curve to it, giving the whole skin area a surface strenght that will resist oil canning and flutter in flight. This will reduce the cracking around many of the rivets on the trailing edge.
Ron Sutton Yaw String

[captain_john]

Ronald, I know the inherent cracking that you are talking about. The early sixes are prone to it as well.

Van has gone to thicker skins on these models to mitigate the problem.

How did you arrive at your decision to put a bow in the stiffies? Does it have any adverse impacts anywhere else to the design?

Just looking into the option a little bit deeper is all. Please don't be offended.

CJ

[Ronald Sutton]

By fluting the stringers 3/4 of an inch gives a curve to the skin, as well as a even smooth surface for the air to pass over, and not creating any turbulence that would cause the skin to vibrate causing stress on the attaching rivets