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 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.
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?
Looking at the procedure, including terrain depictions and the Minimum Safe Altitude (MSA) circle, anticipate the altitudes you'll fly for each segment of the approach including vectors) up to the Final Approach Fix.
119's minimum safe altitudes, we're expected to stay 500 feet from people or structures, plus 1000 feet above and 2000 feet horizontal over congested areas.
Additionally, the controller shouldn't assign a fixed altitude for vertical separation; however, they should ensure that there is at least 1000 feet of separation below any other IFR traffic, consistent with the minimum safe altitudes outlined in 14 CFR [section] 91.
Don't operate below minimum safe altitudes if uncertain of position or ATC clearance.
A series of 1980s-era accidents drove revised chart designs to minimize confusion between primary and secondary navaid frequencies, approach minimums and minimum safe altitudes.

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