Ed Sullivan wrote:

On Sat, 11 Jun 2005 00:04:10 -0400, vincent p. norris
wrote:

Friend of mine said at lunch today that the upper wings of biplanes
have no dihedral. Hementioned specificlaly the Stearman PT-17.

I believe he was mistaken. I know the Sopwith Camel upper wing was
flat but I think the PT-17 and most other biplanes have dihedral in
both wings.

Any expert comments?

Thanks. vince norris


Some biplanes have sweptback wings which provide the same effect as
dihedral. My parasol Jungster II has sweepback and no dihedral.

Ed Sullivan

Why is that Ed?...dihedral provides lateral stability by making
the 'downgoing wing' increase it's lift while the 'upgoing'
wing's lift decreases, so how does the 'sweep-back' provide
lateral stability?
--


-Gord.

"I'm trying to get as old as I can,
and it must be working 'cause I'm
the oldest now that I've ever been"