m metre (= 3.279 ft)
M re: Mach
m/s meters per second (1 m/s = 1.94 kts = 3.6 km/h = 197 fpm)
MAC Mean aerodynamic chord
also:   Military Airlift Command (USAF)
Mach Mach number; the aircraft speed divided by the speed of sound; in a standard atmosphere at s/l Mach 1 is 661 kts (1225 km/h); at 36000 ft Mach 1 is 574 kts (1063 km/h)
MAD Magnetic anomaly detector
also:   Mutually assured destruction
MAG Marine Air Group (USMC)
manifest List of all passengers and cargo for a specific flight
MANPADS Man-portable air defence system
MAP Military Aid Program
also:   Mutual Assistance Program
also:   Military Assistance Program
MAPO Moscow Aircraft Production Organisation
MARS Mid-Air Recovery/Retrieval System (USN/USAF)
MARV Manoeuvring re-entry vehicle
mass balance Weight attached to control surface; reduces or eliminates flutter
MATS Military Air Transport Service; predecessor of MAC (USAF)
MATZ Military air traffic zone
MAW Marine Air Wing (USMC)
also:   Military Airlift Wing (USAF)
MAWS Missile approach warning system
mb Millibar; re: bar
MC Magnetic course
MCAS Marine Corps Air Station (USMC)
MCM Mine counter measures
MCP Maximum continuous power
MCU Management control unit
MEDA Military emergency diversion airfield
medevac Medical evacuation
MEP Mission equipment package
MER Multiple ejector rack
MEWSG Maritime Electronic Support Warfare Group (UK)
MEZ Maritime exclusion zone
MF Medium frequency
MFD Multi-function display
MG Machinegun
MGTOW Maximum gross take-off weight
MH Magnetic heading
MHz Megahertz; aka 'Megacycles'
Microlight Class of manned aircraft with very low MTOW, usually below 500 kg (1100 lbs). No single comprehensive definition can be given, as rules for these aircraft differ significantly per country.
MIL-STD Military standard
MILSTAR Military Strategic and Tactical Relay (US)
MIN Minute
MIRV Multiple independently-targeted re-entry vehicles
MIS Missile Squadron (US)
missed approach An approach which is aborted, followed by an overshoot
MLA Microlight aircraft; re: microlight
MLS Microwave landing system
MLU Mid-life upgrade
also:   Mid-life update
MLW Maximum landing weight
mm Millimetre
MMH/FH Maintenance man-hours per flight hour
MMO Maximum operating Mach number
MMS Mission management system
also:   Mast-mounted sight (helicopter)
MNE Mach number never to exceed; not used in normal flight; available in emergency
MMWR Millimetre wave radar
MNM Minimum
MoA Memorandum of agreement
MoD Ministry of defence
mod Modified
also:   Modification
MOGAS Automotive gasoline
monocoque Construction method in which all strenght is in the outer skin and directly underlying stringers and frames, without any interior structure
MoU Memorandum of understanding
MPA Maritime patrol aircraft
also:   Man-powered aircraft
MPC Missile practice camp
MPD Multi purpose display
mph Miles per hour (1 mph = 1.609 km/h = 1.151 kts)
MPL Multicrew pilot license
MPR Military power reserve
also:   Maximum power reserve
MR Maritime reconnaissance
also:   Medium range
MRAAM Medium range air-to-air missile
MRL Multiple rocket launcher
MRO Maintenance, repair and overhaul
MRW Maximum ramp weight
MSA Minimum safe altitude
MSIP Multi stage improvement programme
also:   Multinational staged improvement programme
MSL or msl Mean sea level
MSN Manufacturer's serial number
MSPS Modular self protection system
MT Magnetic track
MTA Military training area
MTBF Mean time between failure
MTBM Mean time between maintenance
MTBO Mean time between overhauls
MTBR Mean time between removals
also:   Mean time between repairs
also:   Mean time between replacement
MTD Moving target detection
MTI Moving target indicator; a radar facility
MTM Maximum taxi mass
MTOGW Maximum take-off gross weight
MTOM Maximum take-off mass
MTOW Maximum take-off weight
MTT Multiple target tracking
MU Maintenance Unit (RAF)
MW Medium wave
also:   Missile Wing (USAF)
MYP Multiyear procurement (US)
MZFW Maximum zero fuel weight
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