What is the primary effect of a forward (nose-heavy) center of gravity on a fixed-wing aircraft or UAS?
AIncreased longitudinal stability but reduced elevator effectiveness and increased drag from nose-heavy trim.✓ Correct answer
BReduced stability and an uncontrollable tendency to pitch nose-up.
CNo effect on flight characteristics: CG only matters at takeoff and landing.
Why →A forward CG increases longitudinal stability. The aircraft naturally returns to level flight after disturbances. However, it requires more back-pressure to maintain level flight, creating more drag. If CG is too far forward, the elevator may lack authority to rotate on takeoff or flare on landing.
The trap →Reduced stability describes an aft CG, not forward. Too far forward is still dangerous, just differently: the risk is running out of elevator authority, not losing stability.
Field note →For multirotor drones, the flight controller compensates for CG offset by trimming motor outputs. A severely off-center payload can reduce controllability headroom in a motor-failure scenario where the FC can no longer fully compensate.