Minimum Safe Altitude (MSA)
Minimum Safe Altitude (MSA)
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10.Jan.2021
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SKYbrary Aviation Safety. (January 10, 2021). Minimum Safe Altitude (MSA).
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Definition
Minimum Safe Altitude (MSA) is a generic expression, used in various cases to denote an altitude below which it is unsafe to fly owing to presence of terrain or obstacles. An ICAO definition of the term "minimum safe altitude" as such does not exist.
Description
Minimum altitudes are calculated in relation to the highest terrain or obstacle within a specified area, allowing a buffer for error, and adding a specified margin.
Minimum altitudes associated with Controlled Airspace may be published in the states' AIPs.
The expression "minimum safe altitude" is also used in relation to the Minimum Safe Altitude Warning (MSAW) function of ATC systems.
Note. The acronym MSA is also often used as a substitute for "minimum safe altitude". However, the International Civil Aviation Organisation (ICAO) definition of the acronym MSA is Minimum Sector Altitude (MSA). When the abbreviation MSA is encountered, care should be taken to establish which term it refers to.
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- ATS Route
- Minimum En-route Altitude (MEA)
- Minimum Obstacle Clearance Altitude (MOCA)
- Minimum Sector Altitude (MSA)
- Navigation Flight Plan
- Operations Manual (OM)
- Terminal Arrival Altitude (TAA)
- Read-back or Hear-back
- CFIT Precursors and Defences
- Controlled Flight Into Terrain (CFIT)
- Terrain Awareness
- Visual Navigation
- Flying a Visual Approach
- In-Flight Fire: Guidance for Controllers
- Pressurisation Problems: Guidance for Controllers
- Altimeter Temperature Error Correction
- Minimum Safe Altitude Warning (MSAW)
- Area Minimum Altitude (AMA)
- Airworthiness Function Flights - Guidance for Controllers
- Runway Overrun After Unstabilised Approach (OGHFA SE)
- Automatic Emergency Descent System
- Emergency Descent: Guidance for Controllers
- Flight Preparation and Conducting Effective Briefings (OGHFA BN)
- Just Culture in Day-to-Day Operations
- Pilot Memory Aids
- Pilot-Controller Communications (OGHFA BN)
- Pressurisation Problems: Guidance for Flight Crews
- VFR Loss of Positional Orientation: Guidance for Controllers
- Volcanic Ash: Guidance for Controllers
- International Civil Aviation Organization (ICAO)
