MLDI-
(See METER LIST DISPLAY INTERVAL.)
MLS-
(See MICROWAVE LANDING SYSTEM.)
MLS CATEGORIES-
a..
MLS Category I. An MLS approach procedure which provides for an approach to a height above touchdown of not less than 200 feet and a runway visual range of not less than 1,800 feet.

b..
MLS Category II. Undefined until data gather-ing/analysis completion.

c.
MLS Category III. Undefined until data gathering/analysis completion.

MM-
(See MIDDLE MARKER.)
MNPS-
(See MINIMUM NAVIGATION PERFORMANCE SPECIFICATION.)
MNPSA-
(See MINIMUM NAVIGATION PERFORMANCE-SPECIFICATION AIRSPACE.)
MOA-
(See MILITARY OPERATIONS AREA.)
MOCA-
(See MINIMUM OBSTRUCTION CLEARANCE ALTITUDE.)
MODE- The letter or number assigned to a specific pulse spacing of radio signals transmitted or received by ground interrogator or airborne transponder components of the Air Traffic Control Radar Beacon System (ATCRBS). Mode A (military Mode 3) and Mode C (altitude reporting) are used in air traffic control.

(See INTERROGATOR.)
(See RADAR.)
(See TRANSPONDER.)
(See ICAO term MODE.)
(Refer to AIM.)
MODE (SSR MODE) [ICAO]- The letter or number assigned to a specific pulse spacing of the interrogation signals transmitted by an interrogator. There are 4 modes, A, B, C and D specified in Annex 10, corresponding to four different interrogation pulse spacings.
MODE C INTRUDER ALERT-A function of certain air traffic control automated systems designed to alert radar controllers to existing or pending situations between a tracked target (known IFR or VFR aircraft) and an untracked target (unknown IFR or VFR aircraft) that requires immediate attention/ action.
(See CONFLICT ALERT.)
MONITOR- (When used with communication transfer) listen on a specific frequency and stand by for instructions. Under normal circumstances do not establish communications.
MONITOR ALERT (MA)- A function of the ETMS that provides traffic management personnel with a tool for predicting potential capacity problems in individual operational sectors. The MA is an indication that traffic management personnel need to analyze a particular sector for actual activity and to determine the required action(s), if any, needed to control the demand.
MONITOR ALERT PARAMETER (MAP)-The number designated for use in monitor alert processing by the ETMS. The MAP is designated for each operational sector for increments of 15 minutes.
MOSAIC/MULTI-SENSOR MODE- Accepts posi-tional data from multiple radar or ADS-B sites. Targets are displayed from a single source within a radar sort box according to the hierarchy of the sources assigned.
MOVEMENT AREA- The runways, taxiways, and other areas of an airport/heliport which are utilized for taxiing/hover taxiing, air taxiing, takeoff, and landing of aircraft, exclusive of loading ramps and parking areas. At those airports/heliports with a tower, specific approval for entry onto the movement area must be obtained from ATC.