Question

When flying over mountainous areas where temperatures are much lower than ISA, pilots must add ___________ feet to their MEA/MOCA

Answer 1

Pilots must add 1,000 feet to their MEA and MOCA when flying over mountainous areas with surface temperatures much lower than ISA for safety and adequate terrain clearance.

Step-by-step explanation:

When flying over mountainous areas where temperatures are much lower than the International Standard Atmosphere (ISA), pilots must consider the effect of cold temperature on their altimetry. Lower temperatures cause a decrease in air pressure, which in turn causes the altimeter to read higher than the actual altitude of the aircraft. Therefore, to ensure adequate terrain clearance and maintain safety, pilots must add 1,000 feet to their Minimum Enroute Altitude (MEA) and Minimum Obstacle Clearance Altitude (MOCA) when the temperature on the surface is much lower than ISA.