FAA Airline Transport Pilot (ATM)Navigation, Air Traffic Control and ProceduresHard
A published missed approach procedure requires a climb gradient of 300 feet per nautical mile to the missed approach altitude. If the aircraft's groundspeed during the missed approach climb is 140 knots, what climb rate, in feet per minute, is required to comply with this gradient?
- A800 fpm
- B700 fpm
- C500 fpm
- D600 fpm
Show answer & explanationAnswer & explanation
Correct answer: B. 700 fpm
Climb rate (fpm) is found by multiplying the required gradient (ft/NM) by the groundspeed (knots) and dividing by 60: (300 × 140) / 60 = 700 fpm. The crew must verify the aircraft can achieve at least this climb rate to meet obstacle clearance requirements.
Why the other options are wrong
- A. This exceeds what is needed for 300 ft/NM at 140 knots groundspeed.
- C. This value would only satisfy a gradient near 214 ft/NM, not 300 ft/NM.
- D. This corresponds to roughly 257 ft/NM, below the required gradient.
Climb Gradient to Climb Rate Conversion
Published climb gradients (in feet per nautical mile) must be converted to a required climb rate (feet per minute) based on groundspeed to verify aircraft performance during departure or missed approach.
- Formula: Climb rate (fpm) = Gradient (ft/NM) × Groundspeed (kt) / 60
- Standard missed approach gradient is 200 ft/NM unless otherwise published
- Higher published gradients indicate obstacles requiring steeper climbs
- Groundspeed, not airspeed, must be used in the calculation
Memory trick: 'Gradient times Groundspeed, divide by 60 — that's your climb, no fuss.'