What is the MSA and its radius?

What is the MSA and its radius?

• A. Minimum Safe Altitude - 15nm radius
• B. Maximum Safe Altitude - 25nm radius
• C. Mean Safe Altitude - 25nm radius
• D. Minimum Safe Altitude - 25nm radius

Answer: (D)

Minimum Safe Altitude is the altitude that ensures obstacle clearance in the area around a navigation aid. On IFR navigation charts it’s shown as a circle with a 25 nautical mile radius centered on the VOR or navaid. Within that circle, flying at or above the MSA provides safe clearance from terrain and obstacles, typically offering about 1000 feet of clearance in non-mountainous areas (2000 feet in mountainous regions). The radius of 25 NM is the standard used for MSAs. So the correct pairing is that the MSA is a Minimum Safe Altitude with a 25 NM radius.

Minimum Safe Altitude is the altitude that ensures obstacle clearance in the area around a navigation aid. On IFR navigation charts it’s shown as a circle with a 25 nautical mile radius centered on the VOR or navaid. Within that circle, flying at or above the MSA provides safe clearance from terrain and obstacles, typically offering about 1000 feet of clearance in non-mountainous areas (2000 feet in mountainous regions). The radius of 25 NM is the standard used for MSAs. So the correct pairing is that the MSA is a Minimum Safe Altitude with a 25 NM radius.