hypoxia a medical condition caused by lack of oxygen at or above 12,500 feet, marked by a sense of euphoria, increasing disorientation, and, eventually, unconsciousness.
Icarus in Greek mythology, the son of Daedalus, who flew so high on artificial wings that the sun melted the wax fastenings and he fell into the sea and drowned.
icing the formation of ice on any part of an aircraft, but especially the airfoils.
ILS instrument landing system; a landing system comprising marker beacons, high-intensity runway lights, and two radio beams that provide vertical and horizontal guidance to pilots.
inertial navigation system a self-contained airborne system that continuously computes and displays navigational data, replacing the need for a navigator on many flights.
jet engine an engine that mixes oxygen and fuel, converting them into a powerful jet of heated gas, which is expelled under high pressure.
jet stream a river of high-speed winds, usually circulating from west to east at high altitudes, used to aid jet flights when traveling in the same direction.
knot 1 nautical mile per hour, the standard measurement of speed in aviation, equal to 1.1515 miles per hour.
lazy eights alternating 180° climbing and descending S-turns, usually executed for show.
lift the aerodynamic forces that lift an aircraft.
longeron a long spar running from the bow of the fuselage to the stern.
loran long range navigation; a system in which the position of an aircraft is plotted by comparing the time intervals between radio signals from a network of ground stations.
Mach the ratio between the speed of an aircraft and the speed of sound. For example, an aircraft flying at Mach 2 would be traveling at two times the speed of sound.
marshaller a taxiway crew member who uses bats or batons to direct aircraft ground traffic.
marshalling ground crew signaling with batons to direct aircraft ground traffic.
Mayday the international distress call.
microwave landing system a radio landing aid guiding aircraft to a runway from several directions by a microwave beam.
payload cargo, baggage, and passengers.
pitching the nose of an airplane forced up or down by wind.
port light the red light situated on the left side of aircraft, an identification and anticollision aid. See starboard light.
pressurize in an aircraft compartment, to create an air pressure higher than the low atmospheric pressure found at high altitudes.
prop wash the powerful air current driven behind an aircraft by its propellers; also known as the slipstream.
red-eye an overnight or late-night flight.
rib one of the fore-and-aft supporting members in a wing.
roll to roll left or right; also an acrobatic maneuver in which the craft is rotated completely around while maintaining course.
roll-out the distance an aircraft requires to come to a safe stop after touchdown.
rudder the hinged surface on the tail that is used to turn the airplane left or right.
slipstream the airstream behind the propeller.
sonic boom the explosion heard when an aircraft breaks the speed of sound.
sortie an aircraft sent out on a single military mission.
spin an out-of-control, rotating descent, evolving from a stall.
spinner the spinning, cone-shaped covering over the propeller hub.
spiral a tight, descending turn or series of turns.
spoiler one of the special flaps raised on the wings to "spoil" lift by disrupting airflow, used to slow an aircraft or greatly increase the rate of descent.
stabilizer a fixed horizontal surface on the tail to which the elevator is attached, providing longitudinal stability.
stack when landings are delayed, two or more aircraft circling one above the other at 1,000-foot intervals awaiting approach clearance.
stall the loss of lift when airspeed is too slow, resulting in the nose pitching down and the plane fluttering like a falling leaf.
standing waves the currents of air created by a strong wind blowing over a mountain, hazardous to aircraft.
starboard light the green light situated on the right side of aircraft, an identification and anticollision aid.
strobes the bright, white flashing lights situated on the wingtips as an anticollision aid.
supersonic faster than the speed of sound.
TACAN tactical air navigation system; an electronic navigational aid used principally by the military.
taxi to maneuver an airplane on the ground.
TCAS traffic alert and collision avoidance system; an onboard, radar-based collision alerting system.
thermal a rising column of warm air, adding lift to light aircraft.
thrust the force of the engines that propel the craft forward.
three-point landing a perfect landing.