Longitudinal control of a hang glider by weight shift is not always adequate for recovery from a vertical dive. According to Lanchester's phugoid theory, recovery from rest to horizontal flight ought to be possible within a distance equal to three times the height of fall needed to acquire level flight velocity. A hang glider, having a wing loading of 5 kg sq m and capable of developing a lift coefficient of 1.0, should recover to horizontal flight within a vertical distance of about 12 m. The minimum recovery distance can be closely approached if the glider is equipped with a small all-moveable tail surface having sufficient upward deflection.
Dynamics of ultralight aircraft: Dive recovery of hang gliders
1977-05-01
Report
No indication
English
AIAA | 1991
|NTRS | 1981
Dynamics and control of hang-gliders
AIAA | 1989
|NTRS | 1976