FAA Airline Transport Pilot (ATM)Navigation, Air Traffic Control and ProceduresHard
An airliner experiences two-way radio communications failure while operating IFR in IMC, prior to reaching the last assigned altitude. ATC's last transmission assigned a climb to FL350, but the MEA for the current route segment is FL310, and no altitude was included in the route clearance as 'expect.' What altitude should the pilot maintain?
- AThe altitude at the time of failure, regardless of MEA or assignment
- BThe lowest usable altitude for the aircraft's weight
- CFL350, the last assigned altitude
- DFL310, the MEA for the segment
Show answer & explanationAnswer & explanation
Correct answer: C. FL350, the last assigned altitude
Per 14 CFR 91.185, during two-way radio failure the pilot must fly the highest of the MEA, the last assigned altitude, or an expected altitude for that route segment; since FL350 (last assigned) is higher than the FL310 MEA and no expected altitude was given, FL350 must be maintained.
Why the other options are wrong
- A. The rule requires selecting the highest of MEA/expected/assigned, not simply maintaining the current altitude.
- B. Weight-based minimum altitude is not part of the 91.185 lost communication rule.
- D. The MEA is lower than the last assigned altitude, so it is not the highest and does not apply here.
Lost Communication Altitude Rule (91.185)
During IFR two-way radio failure, a pilot must fly the highest of the minimum en route altitude (MEA), an expected altitude given by ATC, or the last assigned altitude for each route segment.
- Route: as assigned, vectored, expected, or filed (AVEF)
- Altitude: highest of MEA, expected, or assigned (MEA)
- Rule applies specifically under 14 CFR 91.185
Memory trick: Remember MEA: MEA, Expected, Assigned — fly the highest