What are the consequences of a forward CG on stall speed, elevator effectiveness, and takeoff performance?

• A. A forward CG increases stall speed, reduces elevator effectiveness, and typically requires a higher rotation speed and longer takeoff distance
• B. A forward CG decreases stall speed and reduces takeoff distance
• C. A forward CG reduces drag and increases climb rate
• D. A forward CG has no effect on takeoff

Answer: (A)

Putting the CG forward makes the airplane more pitch-stable. That extra stability means the nose-down tendency is stronger and the elevator has to work harder to raise the nose for liftoff. Because more of the elevator’s authority is tied up in balancing the aircraft and countering the nose-down moment, the elevator’s effectiveness is reduced when you’re trying to rotate. As a result, you typically must rotate at a higher airspeed to achieve the proper takeoff attitude, which in turn tends to lengthen the takeoff run.

The forward balance also affects the wing’s available lift margin. With the nose-down tendency needing counteracting lift, the wing reaches its stall condition at a slightly higher airspeed, so stall speed increases.

In short, a forward CG makes the airplane more stable, reduces elevator effectiveness, and raises the rotation speed and takeoff distance.