Roll Stability in lifting body and flying wing aircraft

"Fred the Red Shirt" wrote in message
om...
IIUC, the B-2 and F-117 rely on continuous feedback and control,
they could not be flown without computers.

So how do lifting bodies and Flying Wings like the facetmobile or the
Chance-Vought V-173 "Flying Flapjack" maintain roll stability? They
appear to have no or negative dihedral.

--

FF

Having helped build and test fly a flying wing, maybe I can help.

To the roll stability question there are two answers.

1. You don't really need roll stability as long as you don't have real roll
instability. Pilots can easily keep the wings level.

2. Sweep back has the same effect as dihedral. Sometimes the dihedral
effect of sweep is so strong that anthedral (negative dihedral) is needed to
give the aircraft maneuverability.

Pitch stability comes mainly from the airfoil choice. Or, in the case of
swept back flying wings, from wing twist. Sometimes, it's a combination of
both.

Yaw stability and control is the big problem of flying wings. Here,
computer stability augmentation is very useful.

Bill Daniels