abort	to break off or abandon a mission - mechanical problems were a major cause of aborts.
Ace	a pilot who has shot down five aircraft (scored five victories)
acceleration	rate of change of velocity, sometimes the term deceleration is used when velocity is decreasing.
accelerometer	a device that precisely measures changes in acceleration
aerial	antenna
aerodrome	airbase
aerodynamic	an object with a shape that allows it to fly.
air raid	a bombing attack by aircraft
airdrop	the dropping of supplies by aircraft, typically canisters or crates which deploy parachutes.
airlift	a sustained effort to move men and/or supplies via aircraft.
airfoil	a shape such that air flows faster over one side than the other, generating lift - a wing is an airfoil.
ailerons	interconnected flaps at the rear of the wings which move in opposite directions, allowing the plane to roll (bank).
airburst	the detonation of a shell or bomb above the ground, this usually causes more damage to personnel.
airscrew	propeller
aircraft carrier	a dedicated ship which can launch and receive aircraft.
airframe	the structure that supports the loads acting upon the airplane.
anti-aircraft gun	gun capable of high elevation and fairly rapid fire.
anti-tank gun	high-velocity gun that fires armor-piercing shells on a flat trajectory.
apex	the point towards which an object is moving.
apoapsis	high point of an orbit.
apogee	the highest point in a trajectory.
armament	the weapons that are part of a plane, ship, tank or other vehicle.
Apron	A defined area on an airfield intended to accommodate aircraft for purposes of loading or unloading passengers or cargo, refueling, parking, or maintenance.
armistice	suspension of hostilities by agreement between the opponents
allied	joined or united in a close relationship.
altitude	the height of a vehicle above ground or sea level.
asteroid belt	region of space between Mars and Jupiter where the most asteroids are found.
astrophysics	study of physics of astronomical objects and phenomena.
attitude	the state of a vehicle's roll, pitch and yaw at a given moment.
AU	distance from the Earth to the Sun (about 93 million miles).
aviation	pertaining to the operation, design, development and production of an aircraft.
back up	someone who takes the place of another, a substitute.
bandit	enemy aircraft
bearing	direction
bogie	unidentified aircraft
bomb	an explosive device dropped by an aircraft. at first, little more than artillery shells with fins but steady improvements followed. Generally the amount of explosive making up the total weight of the bomb increased, the shape became more streamlined and they also became more specialized for the target and mission (cluster and incendiary bombs for example)
bombsight	can be rudimentary, but often consisted of a device that could compensate for the major factors that affect the trajectory of falling bombs: altitude, airspeed, crosswinds, etc.
bomber	an aircraft designed to carry and deliver a payload of bombs against enemy targets
booster(rocket)	a high thrust rocket that quickly gets a vehicle up to speed.
bulkhead	a partition that divides a ship or plane into compartments.
caliber	The diameter of a shell measured in fractions of an inch or millimeters.
calibration	setting an instrument before measuring to insure accurate results.
cannon	guns 20mm and larger firing shells containing a small explosive charge. see machine gun.
canopy	the transparent enclosure over an airplane cockpit
CapCom	Capsule Communicator - voice link between a spacecraft and mission control.
casualties	military personnel lost through death, wounds, injury, sickness, internment, or capture or through being missing in action.
ceiling	the highest altitude a piece of artillery can throw a projectile. Also refers to the highest altitude an aircraft can reach and maintain flight
centrifugal force	the outward force felt by a body rotating about an axis.
CO	Commanding Officer
cockpit	a space or compartment in a airplane from which it is piloted
commander	a person who commands a mission.
contrarotating propellers	propellers that spin in opposite directions.
crater	a round impression left in a planet or moon from a meteoroid collision.
crew	the men needed/assigned to a particular vehicle, gun, or other piece of ordnance.
detonate	explode
downlink	radio connection by which a spacecraft cen communicate back to Earth.
drop tanks	external fuel tanks
drop zone (DZ)	designated area for paratroopers to jump
drag	resistance of the air to the airplane's passage through it.
elevators	flaps on the back edge of an aircraft's tail plane that control pitch.
EVA	Extra Vehicular Activity - activities outside the spacecraft such as a spacewalk.
fighter	aircraft whose main purpose is to destroy enemy aircraft.
fighter-bomber	aircraft purpose-built but more often adapted to carry and launch bombs, rockets or other ordnance.
flying boat	aircraft whose main body consists of a single hull, or boat, that permits take-off or landing on water.
flame-out	the sudden unplanned extinction of combustion in a jet engine
flaps	hinged wing surfaces that are lowered to give more lift at low speeds
flying wing	an aircraft design where the wing forms virtually the entire airplane.
formation	an ordered arrangement of two or more aircraft proceeding together.
glider	an airplane that is towed into the air then released. a glider has a pilot and control surfaces so it can be 'flown' during its descent.
hangar	a large enclosure for aircraft.
helio	prefix referring to the Sun.
hangar deck	the deck below the flight deck where aircraft are stowed and made ready on an aircraft carrier.
horsepower	The rate of doing work. 1 horsepower = 550 foot pounds per second
inertia	the resistance of an object to a change in velocity.
interceptor	a fighter designed to quickly climb and intercept incoming aircraft
jet (turbo-jet)	an engine that produces a high speed jet of heated air, this exhaust pushes the aircraft forward.
knots (kts)	speed in nautical miles per hour.
lift	the upward acting force that counters a plane's weight.
light year	the distance light travels in a vacuum in one year.
lunar	referring to the moon.
magnetic field	a region of space around a magnetized body where magnetic forces are present.
main armament	the primary weapon(s) of a ship, plane or tank.
Mach	the speed of sound defined.
machine gun (MG)	a gun for sustained rapid fire that uses bullets.
meteor	luminous effect seen when a meteoroid enters the atmosphere (a shooting star).
meteorite	part of a meteoroid that survives entry through the Earth's atmosphere.
meteoroid	a small space rock
missile	guided rocket or jet.
MMS	Manned Maneuvered Spacecraft.
MMT	Mission Management Team.
module	detachable compartment of a spacecraft.
momentum	The total energy of an object (mass times velocity).
orbit	the path of an object that is moving around another object.
ordinance	military supplies including weapons, ammunition, combat vehicles, and maintenance tools and equipment
parachute	a high drag device made of silk, nylon or other strong, lightweight material used to slow the descent of a falling object/person to manageable speeds.
paratroopers	troops trained to 'jump' (parachute) from aircraft
periapsis	low point of an orbit.
photo reconnaissance (PR)	reconnaissance conducted by camera equipped aircraft
pilot	person who operates an aircraft or spacecraft in flight.
primary objectives	main purpose.
prototype	A model suitable for evaluation of design, performance, and production potential.
propeller (prop)	airfoil that generates thrust
psi	pounds per square inch, a measure of pressure
radar	(radio direction and ranging)
radiation belt	region of charged ions and electrons in space
reconnaissance	one of the most important activities of any armed force. Up-to-date reports on enemy strength and movement are key to success in offensive or defensive operations.
rudder	a large flap on the vertical stabilizer (tail fin) that controls yaw.
satellite	a body that orbits another body.
statute miles	a unit of length equal to 1,760 yards.
spin	a dangerous situation for an aircraft when, after suffering a stall (loss of lift), one wing creates lift while the other is stalled - this causes the aircraft to rapidly spin and if not corrected results in a crash.
strafe/strafing	when an airplane uses machine guns and/or cannon to attack surface targets.
sortie	one mission flown by one aircraft, standard measure of air power
spoiler	control surface in the form of a small plate presented more or less square-on to the airstream causing high drag and possible loss of lift.
subsonic	below the speed of sound.
supercharger	gear-driven air compresser powered by the airplane's engine. also called 'blower'
supersonic	faster than the speed of sound.
terminal velocity	a maximum speed (velocity) reached by a falling object due to air drag.
thrust	the force that pushes an aircraft forward in flight. static thrust is the usual measure of jet engine performance, giving the thrust when the engine is at rest
torpedo	a relatively sophisticated and deadly weapon, torpedoes can be launched from subs, surface ships or aircraft (aerial torpedoes).
transatlantic flight	a flight across the Atlantic Ocean.
transonic	just below and just above the speed of sound, very important to understanding control and stability in high-speed aircraft.
turbine	a motor in which a set of blades rotates when struck by a moving stream of liquid or gas.
VAB	Vehicle Assembly Building.
velocity	speed and direction of an object.
yaw	the rotation of an aircraft or missile about its vertical axis
zenith	At the very top. The highest point.