FAA Airline Transport Pilot (ATM)Aircraft Performance and Weight and BalanceMedium
Per 14 CFR Part 25 certification standards, immediately after liftoff with the critical engine inoperative, the landing gear still extended, and the airplane at V2, what minimum climb gradient must a two-engine transport category airplane demonstrate during the first segment of the takeoff flight path?
- AA positive climb gradient, greater than zero percent
- BA minimum climb gradient of 2.4 percent
- CA minimum climb gradient of 1.2 percent
- DA negative gradient is acceptable as long as airspeed is maintained
Show answer & explanationAnswer & explanation
Correct answer: A. A positive climb gradient, greater than zero percent
The first segment of the takeoff flight path (from liftoff to gear retraction) requires only that the climb gradient be positive with the critical engine inoperative and gear still extended. The 2.4% requirement applies to the second segment (gear retracted, flaps in takeoff position), and 1.2% applies to the final (fourth) segment for two-engine airplanes.
Why the other options are wrong
- B. 2.4% is the second-segment requirement, not the first segment.
- C. 1.2% is the final-segment requirement for two-engine airplanes, not the first segment.
- D. A negative gradient would mean the airplane is descending, which is not certifiable.
First Segment Climb Gradient
The climb segment from liftoff to gear retraction with the critical engine inoperative; Part 25 requires only a positive climb gradient with gear extended.
- Occurs from liftoff to gear-up selection
- Gear is still extended during this segment
- Requirement is simply positive (greater than zero) gradient
- Distinct from the 2.4% second-segment requirement
Memory trick: First segment: just don't sink — gear's still hanging down