Area Minimum Altitude
Area Minimum Altitude (AMA) is the lowest IFR altitude that provides a minimum vertical clearance of 1,000 ft above all obstacles within a defined geographic sector (2,000 ft in designated mountainous areas). AMA values are published on IFR en route charts and apply when operating off airways in Canadian domestic airspace.
Purpose
When flying off published airways under IFR, there is no MEA or MOCA to reference. AMA fills this gap, providing a sector-based obstacle clearance altitude as a safety floor. It is the standard IFR reference for off-airway operations in Canada.
How to Use AMA
- Identify the AMA sector covering your route on the IFR low-altitude en route chart
- Do not descend below AMA unless a positive position fix has been established
- In mountainous areas, the 2,000 ft buffer reflects rapidly changing terrain — treat it with respect
- AMA is not an approach minimum — use published approach procedures for descent at destination
AMA vs. MEA vs. MOCA
- AMA: Geographic sector minimum for off-airway IFR flight
- MEA: On-airway minimum; guarantees both obstacle clearance and navaid reception
- MOCA: On-airway minimum; guarantees obstacle clearance, navaid reception only within 22 NM
On the TC Written Exam
The AMA/MEA/MOCA distinction is a CPL exam staple. AMA = off-airway; MEA and MOCA = on-airway. In mountains, all minimums are higher.