Abstract: Normal configurations of fixed-wing MAV(Micro Aero Vehicle) have very short horizontal tail moment-arm by reason of their dimensional limitation. Such configurations result in poor stability and low aerodynamic efficiency. This paper discusses the idea of improving the longitudinal stability by descending the center of gravity of a fixed-wing MAV without the assistance of horizontal tail. Analysis and flight tests show that such configuration can get pitching moment balance and longitudinal static stability. And the static margin can be adjusted by change the vertical distance between the aerodynamic center and the center of gravity.

Key words: MAV, longitudinal stability, center of gravity, moment balance, aerodynamic center