minimum safe altitude

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Related to minimum safe altitude: Minimum Flight Altitude, Emergency Safe Altitude

minimum safe altitude (MSA)

minimum safe altitude (MSA)
MSA as it appears on IAP charts.
The altitude below which it is hazardous to fly because of the presence of high ground or other obstacles. MSAs are published for emergency use on instrument approach procedure (IAP) charts except RNAV (area navigation) IAPs. The MSA is defined using NDB (nondirectional beacon) or VOR (very high frequency omnidirection radio-range) facilities within a 25 (normally) or 30 NM (maximum) radius. If there is no VOR or NDB within 30 NM of the airport, there will be no MSA. The altitude shown provides at least 1000 ft of clearance above the highest obstacle in the defined sector.
References in periodicals archive ?
The asterisk indicates that the Minimum Safe Altitude Warning system is turned off for that aircraft, so he can fly as low as he wants without triggering MSAW altitude alarms.
The final question is the minimum safe altitude to break out, see the runway, select landing flaps and be +51-0 Vref at 100 feet.
The approach control's Minimum Safe Altitude Warning alert had activated at 2319, and was presented on the radar display as a recurring "LA," indicating low altitude.
The minimum safe altitude (MSA) circle deserves more than a passing glance in mountainous areas.
On the departure airport's IAP chart you'll also find the area's minimum safe altitude (MSA--sometimes minimum sector altitude) for each quadrant.
The minimum safe altitude along your propsed route is a heckuva lot higher than pattern altitude at home, isn't it?
Minimum Safe Altitude (MSA) is now "expressed in feet
The Minimum Safe Altitude in this area is 2000 MSL.

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