MIL-HDBK-143A
aps* - Accessory power supply
apu* - Auxiliary power unit.
aql* - Accepted quality level.
area ration - See expansion area ratio.
arl* - Accepted reliability level
armament system - A configuration consisting of a triad of missile components - fuze, safety,
and arming mechanism, and warhead - which is used to produce and control the damage
effects of a missile.
arming - As applied to explosives, the changing from a safe condition to a state of readiness
for initiation.
ARMING DEVICE, GUIDED MISSILE WARHEAD - An item designed to perform the
electrical and/or mechanical alignment necessary to permit the initiation of the explosive train
of a Guided Missile warhead.
arm-to-arm - As used in the ordnance of Guided Missiles, the changing from a safe condition
to a state of readiness in preparation for initiation or ignition of the propulsion system.
artillery Guided Missile - A missile, of comparatively short range, guided to the target by wire
or radio command.
asm* - Air-to-surface missile. see: missile, air-to-ground.
astrotracker - A star tracker.
athodyd - Aerothermodynarnic duct. See: ENGINE, RAMJET.
attitude - The position of a missile as determined by the inclination of its axes to some frame
of reference. If not otherwise specified, this frame of reference is fixed to the earth.
aum* - Air-to-underwater missile. See: missile, air-to-underwater.
autopilot - The autopilot electronics contained within the missile receives target tracking
commands from a seeker, and provides stabilization and steering commands to the missile
control section which responds by positioning aerodynamic fins.
auxiliary propulsion system - A backup system to supply power for a mission if the primary
unit should fail.
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