Minimum crossing altitude (MCA)

Definitions

• The lowest allowed altitude at certain fixes an aircraft must cross when proceeding in the direction of a higher minimum en route altitude (MEA).
• An MCA is the lowest altitude at certain fixes at which the aircraft must cross when proceeding in the direction of a higher minimum en route IFR altitude. MCAs are established in all cases where obstacles intervene to prevent pilots from maintaining obstacle clearance during a normal climb to a higher MEA after passing a point beyond which the higher MEA applies.

References

• Instrument Flying Handbook, Federal Aviation Administration, 2014
• Instrument Procedures Handbook, Federal Aviation Administration, 2017