Glossary

Military training route (MTR). Airspace of defined vertical Minimums section. The area on an IAP chart that displays the and lateral dimensions established for the conduct of military lowest altitude and visibility requirements for the approach. training at airspeeds in excess of 250 knots indicated airspeed (KIAS). Missed approach. A maneuver conducted by a pilot when an instrument approach cannot be completed to a landing. Minimum altitude. An altitude depicted on an instrument approach chart with the altitude value underscored. Aircraft Missed approach point (MAP). A point prescribed in each are required to maintain altitude at or above the depicted value. instrument approach at which a missed approach procedure shall be executed if the required visual reference has not Minimum crossing altitude (MCA). The lowest allowed been established. altitude at certain fixes an aircraft must cross when proceeding in the direction of a higher minimum en route altitude (MEA). Mixed ice. A mixture of clear ice and rime ice. Minimum descent altitude (MDA). The lowest altitude (in MLS. See microwave landing system. feet MSL) to which descent is authorized on final approach, or during circle-to-land maneuvering in execution of a MM. Middle marker. nonprecision approach. MOA. See military operations area. Minimum drag. The point on the total drag curve where the lift-to-drag ratio is the greatest. At this speed, total drag MOCA. See minimum obstruction clearance altitude. is minimized. Mode C. Altitude reporting transponder mode. Minimum en route altitude (MEA). The lowest published altitude between radio fixes that ensures acceptable Moment. The product of the weight of an item multiplied navigational signal coverage and meets obstacle clearance by its arm. Moments are expressed in pound-inches (lb-in). requirements between those fixes. Total moment is the weight of the airplane multiplied by the distance between the datum and the CG. Minimum equipment list (MEL). A list developed for larger aircraft that outlines equipment that can be inoperative for Moment arm. The distance from a datum to the applied force. various types of flight including IFR and icing conditions. This list is based on the master minimum equipment list (MMEL) Moment index (or index). A moment divided by a constant developed by the FAA and must be approved by the FAA for such as 100, 1,000, or 10,000. The purpose of using a moment use. It is specific to an individual aircraft make and model. index is to simplify weight and balance computations of airplanes where heavy items and long arms result in large, Minimum obstruction clearance altitude (MOCA). The unmanageable numbers. lowest published altitude in effect between radio fixes on VOR airways, off-airway routes, or route segments, which meets Monocoque. A shell-like fuselage design in which the obstacle clearance requirements for the entire route segment stressed outer skin is used to support the majority of imposed and which ensures acceptable navigational signal coverage stresses. Monocoque fuselage design may include bulkheads only within 25 statute (22 nautical) miles of a VOR. but not stringers. Minimum reception altitude (MRA). The lowest altitude Monoplanes. Airplanes with a single set of wings. at which an airway intersection can be determined. Movable slat. A movable auxiliary airfoil on the leading edge Minimum safe altitude (MSA). The minimum altitude of a wing. It is closed in normal flight but extends at high depicted on approach charts which provides at least 1,000 feet angles of attack. This allows air to continue flowing over the of obstacle clearance for emergency use within a specified top of the wing and delays airflow separation. distance from the listed navigation facility. MRA. See minimum reception altitude. Minimum vectoring altitude (MVA). An IFR altitude lower than the minimum en route altitude (MEA) that provides MSA. See minimum safe altitude. terrain and obstacle clearance. MSL. See mean sea level. G-20