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

If you realise that monoplanes have been designed with various
anhedrals and dihedrals, why would you suppose that there are no
similar examples in biplanes?

Brian Whatcott Altus, OK