4/20/23 

Pilot/Controller Glossary 

2. 

Emergency Safe Altitude (ESA). Altitudes depicted on approach charts which provide at least 1,000 feet 

of obstacle clearance in nonmountainous areas and 2,000 feet of obstacle clearance in designated mountainous 

areas within a 100-mile radius of the navigation facility or waypoint used as the ESA center. These altitudes are 

normally used only in military procedures and are identified on published procedures as “Emergency Safe 

Altitudes.” 
MINIMUM SAFE ALTITUDE WARNING (MSAW)

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 A function of the EAS and STARS computer that aids 

the controller by alerting him/her when a tracked Mode C equipped aircraft is below or is predicted by the 

computer to go below a predetermined minimum safe altitude. 

(Refer to AIM.) 

MINIMUM SECTOR ALTITUDE [ICAO]

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The lowest altitude which may be used under emergency 

conditions which will provide a minimum clearance of 300 m (1,000 feet) above all obstacles located in an area 

contained within a sector of a circle of 46 km (25 NM) radius centered on a radio aid to navigation. 
MINIMUMS

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Weather condition requirements established for a particular operation or type of operation; e.g., 

IFR takeoff or landing, alternate airport for IFR flight plans, VFR flight, etc. 

(See IFR CONDITIONS.) 
(See IFR TAKEOFF MINIMUMS AND DEPARTURE PROCEDURES.) 
(See LANDING MINIMUMS.) 
(See VFR CONDITIONS.) 
(Refer to 14 CFR Part 91.) 
(Refer to AIM.) 

MINIMUM VECTORING ALTITUDE (MVA)

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 The lowest MSL altitude at which an IFR aircraft will be 

vectored by a radar controller, except as otherwise authorized for radar approaches, departures, and missed 

approaches. The altitude meets IFR obstacle clearance criteria. It may be lower than the published MEA along 

an airway or J-route segment. It may be utilized for radar vectoring only upon the controller’s determination that 

an adequate radar return is being received from the aircraft being controlled. Charts depicting minimum 

vectoring altitudes are normally available only to the controllers and not to pilots. 

(Refer to AIM.) 

MINUTES-IN-TRAIL

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 A specified interval between aircraft expressed in time. This method would more likely 

be utilized regardless of altitude. 
MIS

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(See METEOROLOGICAL IMPACT STATEMENT.) 

MISSED APPROACH

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a. 

A maneuver conducted by a pilot when an instrument approach cannot be completed to a landing. The route 

of flight and altitude are shown on instrument approach procedure charts. A pilot executing a missed approach 

prior to the Missed Approach Point (MAP) must continue along the final approach to the MAP. 

b. 

A term used by the pilot to inform ATC that he/she is executing the missed approach. 

c. 

At locations where ATC radar service is provided, the pilot should conform to radar vectors when provided 

by ATC in lieu of the published missed approach procedure. 

(See MISSED APPROACH POINT.) 
(Refer to AIM.) 

MISSED APPROACH POINT (MAP)

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 A point prescribed in each instrument approach procedure at which a 

missed approach procedure shall be executed if the required visual reference does not exist. 

(See MISSED APPROACH.) 
(See SEGMENTS OF AN INSTRUMENT APPROACH PROCEDURE.) 

MISSED APPROACH PROCEDURE [ICAO]

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 The procedure to be followed if the approach cannot be 

continued. 

PCG M

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