FAA Airline Transport Pilot (ATM)Aircraft Performance and Weight and BalanceEasy
During the takeoff roll of a twin-engine transport, the captain's critical engine suddenly fails at a speed below V1. The airplane is at maximum weight for the runway. Which speed defines the minimum ground speed at which the captain can maintain directional control using rudder alone, staying within 30 feet of the runway centerline, following this engine failure?
- AVMCG
- BVR
- CVMCA
- DV2
Show answer & explanationAnswer & explanation
Correct answer: A. VMCG
VMCG (minimum control speed, ground) is the minimum speed during the takeoff roll at which directional control can be maintained using rudder alone (without nosewheel steering) within 30 feet of centerline after sudden failure of the critical engine. It is a ground-based control speed distinct from VMCA, which applies in flight.
Why the other options are wrong
- B. VR is the rotation speed, unrelated to directional control after engine failure.
- C. VMCA is the minimum control speed in flight, not on the ground during the takeoff roll.
- D. V2 is the takeoff safety speed used after liftoff, not during the ground roll.
VMCG (Ground Minimum Control Speed)
The minimum speed during the takeoff roll at which directional control can be maintained using rudder alone, within 30 feet of runway centerline, after sudden failure of the critical engine.
- Applies only during the takeoff ground roll
- Deviation limited to 30 feet from centerline
- Controlled using rudder alone (no nosewheel steering credit)
- V1 can never be less than VMCG
Memory trick: Ground control needs rudder power before wheels leave the ground