Title

Empirically Derived Biplane Lift as a Function of Gap and Stagger

Document Type

Article

Publication Date

1-2013

Publication Source

Journal of Aircraft

Abstract

A number of methods have been proposed to estimate the lift of a biplane based mostly on potential flow methods and arguments. It is noted that positive and negative stagger are treated identically and that lift increases in direct proportion to stagger. Discussion of lift-induced drag is included because of its implied effect on the lift-curve slope.

It will be shown, however, that at least in the flow régime tested for the present work, the omission of the direction of stagger fundamentally limits the application of these results generated in the early third of the 20th century. The present study began with a vortex lattice model study to reduce the experimental test matrix. A generalized method for the prediction of lift coefficient as a function of gap, stagger, aspect ratio, and angle of attack has been determined empirically and subsequently validated.

It is noted that for a couple of the cases, aerodynamically induced vibration prevented acquisition of data within the same band of low uncertainty.

Inclusive pages

292-298

ISBN/ISSN

0021-8669

Comments

Permission documentation is on file.

Publisher

American Institute of Aeronautics and Astronautics

Volume

50

Issue

1

Peer Reviewed

yes