APPENDIX A GLOSSARY

aerobatics A specialized form of flying in which airplanes diverge from level flight and gentle banking turns in favor of maneuvers that combine loops, rolls, spins, and inverted flight.

aerodynamics A segment of the complex field of fluid mechanics that deals with the motion of air, including the forces it exerts on objects moving through it. aeronaut Archaic phrase describing balloon pilots. Derives from Greek words meaning “voyager of the air.” aerostation Early French word for balloons.

aileron The hinged wing surfaces that are responsible for controlling the angle of bank. Controlled by the pilot using the control column.

aircraft Anything that flies under some kind of human control, including airplanes, helicopters, gyroplanes, gliders, hot-air balloons, gas balloons, airships, and other vehicles.

airfoil A surface whose shape helps create an aerodynamic force.

air pressure The force exerted by the air at a given altitude, produced by the collective collisions of air molecules on measuring devices.

air rage A newly created term describing outraged, sometimes violent expressions of passenger frustration over perceived misdeeds and maltreatment by airlines and onboard crew members.

airship Aircraft combining buoyant gas envelope with engines that permit control other than the simple movement of the winds.

airsickness A form of motion sickness brought on by air travel. Symptoms include light-headedness, increased salivation, sweating, clamminess, pallor, nausea, vomiting, and fatigue.

angle of attack The angle between the relative wind and the angle of the airfoil. Up to a critical angle where a stall occurs, a larger angle of attack translates into greater lift.

aspect ratio An aerodynamics formula that measures how skinny or squat a wing is. It divides the wing’s span by its front-to-back chord.

atmospheric optics The large number of visual phenomena created by the sun’s light reflecting, refracting, diffracting, or diffusing through or around airborne dust, water, and ice.

aviation A catch-all term describing almost any sport or occupation that takes place in the air. Derives from the Latin word avis, meaning “bird.”

avionics A term of art in aviation, combining the words “aviation” and “electronics.” Refers to the navigational and two-way radios, as well as new-generation high – technology devices.

balloon A contained volume of air or gas that, due to its temperature or gas density, becomes buoyant and can transport a cargo of pilot, passengers, or equipment. The balloon’s speed and direction are governed by winds.

barnstormer The name given to itinerant pilots of aviation’s early days who earned a living by selling passenger rides from farm fields and pastures.

barometer A device for measuring air pressure. Variations include the aneroid type, which uses an evacuated container, and the mercury type, which measures the height of a column of mercury in an evacuated glass tube.

basket The portion of a balloon where pilots, passengers, flight instruments, and fuel stay during flight. blackouts In aerobatic flying, the loss of vision or loss of consciousness caused by high g- forces.

canard Wing surfaces positioned in front of the airplane, serving the same purpose of the horizontal stabilizer positioned on the empennage of conventional airplanes.

certificate In flying terms, a certificate is a document that grants legal permission for pilots to operate an aircraft. Most certificates are issued without any expiration date, but pilots must practice certain skills on a regular basis to be able to legally exercise the privileges of their certificates. Certificates include private, commercial, flight instructor, and airline transport pilot.

collective pitch control A control used in rotary – wing aircraft that alters the pitch of all blades simultaneously.

conventional gear The configuration of landing gear featuring a tail wheel and two main gear located beneath the wings.

cyclic pitch control A control used in helicopters to selectively change the pitch of rotors in order to tilt the rotor disk and produce thrust.

dew point The temperature to which a particle of air would have to be chilled in order to force the water vapor contained in it to condense into droplets of visible moisture.

dirigible Massive, rigid-frame airship. Early dirigibles used flammable hydrogen gas for lift and were popular in Germany as cruise vehicles and as wartime aircraft.

dog fight The chaotic air battles between two or more enemy planes. Originally used during World War I, dog fights are still popular in aviation combat.

drag One of the four forces of flight, drag is the retarding force that reduces the effectiveness of thrust. Drag is typically an undesirable side effect of the viscosity of the air, or an unavoidable by-product of lift.

elevator In airplane, the hinged tail structure used to control an aircraft’s pitch. Elevator is controlled by the pilot using the control column. empennage The airplane’s structure that includes horizontal and vertical stabilizers and the aerodynamic elements that sustain smooth flow. envelope In a balloon or airship, a fabric or rubberized bag that is filled with hot air or buoyant gas to provide lift.

FBO Fixed-base operator, the airport business offering aircraft for rent or sale, flight instruction, fuel, maintenance, charter flying service, and flight instruction. If there’s only one business at an airport, it will probably be an FBO.

fixed-wing Indicates a type of aircraft in which the main lift-producing surface is stationary, as in an airplane. See also rotary-wing.

flight instruments Devices that measure parameters of flight, including airplane attitude, altitude, airspeed, rate of turn, direction, and rate of climb or descent. Flight instruments function using either gyroscopes or air pressure.

flight physiology The field of medicine that studies the body’s adaptability to flight and the maladies and injuries that flight can induce.

fuselage The portion of airplane structure that contains the cockpit, passenger cabin, and cargo compartment, and provides an anchor for the wings, empennage and, sometimes, the engine.

glide slope The imaginary slope, as shallow as 3 degrees, that pilots follow during descent to land. The glide slope is sometimes indicated by lights or electronic signals.

gliding A form of aviation in which high-lift airplanes fly by exchanging altitude for speed. Requires a mechanical launch, typically behind a powered airplane or using an automobile tow.

gondola See basket.

graveyard spiral A potentially dangerous maneuver in which a cycle of increasing bank angle, lower pitch angle, and increasing airspeed result in rapid descent. Unless it is remedied quickly and correctly, graveyard spiral can result in structural failure or crash.

gyroplane Also called “autogyro”; an aircraft that derives its lift from a typically free-turning rotor, and its thrust from an airplane – style propeller.

hangar An airport building where aircraft are stored and protected from the elements. Often serves as a place where mechanics and pilots maintain aircraft.

hangar bums Also known as “ramp rats,” a mostly affectionate reference to the groups of pilots and aviation lovers who hang around the airport, often in a favorite hangar or at an airport restaurant or tavern.

hangar flying The most daring, adventurous, and technically perfect form of flying there is—conversation usually carried on by pilots grounded by bad weather. hour The unit of time pilots use to measure flying experience. Usually measured from engine start to engine shut-down.

human factors The study of the factors affecting pilot performance and judgment, including emotions, physical health, relationships to other crew members, and response to stress.

human-powered flight Flight accomplished with no other power source of human pilots or crew members, requiring highly advanced, ultra-lightweight materials.

hypoxia A catch-all term covering a number of conditions in which the blood is robbed of oxygen, or in which oxygen-rich blood is incapable of delivering oxygen to parts of the body that need it.

instruments meteorological conditions (IMC) Combinations of visibility, precipitation, and clouds that, by federal regulations, limit flying to the pilots with instrument ratings and necessary recent flight experience.

Jenny A popular World War I-era trainer that became familiar in the postwar years when pilots purchased thousands of them as surplus for civilian use.

knife-edge flight Flight with a 90-degree bank angle (so that the wings are perpendicular to the ground), in which the fuselage becomes the major lift-producing surface.

knot A unit of speed measuring the number of nautical miles traveled in a given time.

lift One of the four forces of flight, lift is the pressure created by wings or other aerodynamic surface, or buoyancy, that counteracts the pull of gravity.

Mach number The ratio of an airplane’s speed to the speed of sound at flight altitude, density, and temperature; so called in honor of Austrian physicist Ernst Mach. mass ascension The ascension of a large number of hot – air or gas balloons in a brief period of time.

meteorology The science that investigates the atmosphere, including its interaction with earth’s surface, oceans, and life in general.

nautical mile The unit of length used to measure distance in aviation. Longer than the 5,820-foot statute mile commonly used in the United States, the nautical mile measures 6,076 feet in length.

night VFR Flying after sunset under rules that permit flying by pilots untrained in flying solely by instruments. parachute A fabric shroud that carries a payload, usually a person, and uses air resistance to reduce its rate of free fall. preflight inspection A thorough check of all aircraft systems made by pilots before each flight.

rotary-wing Indicates a type of aircraft in which the main lift-producing surface rotates, as in a helicopter or a gyroplane. See also fixed-wing. rotor The powered or free-turning set of airfoils that creates aerodynamic force in helicopters and gyroplanes. rudder In airplanes, the tail structure that controls yaw. Rudder is controlled by foot-operated rudder pedals.

seaplane Airplane equipped with floats in place of landing gear wheels, permitting takeoff, landing, and maneuvering on water. Some seaplane fuselages are designed like boat hulls and don’t need landing gear at all.

scale The size of features on a map.

soaring Staying aloft without losing altitude. Requires an atmospheric boost from wind or sun-generated thermals.

solo Technically, any flight time when a pilot is alone in the cockpit is considered solo time. It takes on extra significance when it represents the very first time a student pilot gets to fly the plane alone, without an instructor on board. The first solo is a memorable benchmark in a pilot’s life.

spatial disorientation A condition of the body’s equilibrium organs resulting in pilot uncertainty over his orientation to the earth’s surface.

spoilers Panels or plates installed on the upper wing surface of airplanes and gliders in order to disrupt the lift-producing flow of air, having the effect of slowing the aircraft or increasing its rate of descent.

stall In aerodynamics, the condition in which the smooth flow of air over the wing becomes turbulent, destroying lift force to a point that it falls below the force of gravity.

thrust One of the four forces of flight, thrust is the force produced by an engine that works in the opposite direction of drag.

thunderstorm A violent convective phenomenon that produces rain, hail, lightning, strong winds, and possibly more severe conditions such as squall lines, tornadoes, and waterspouts.

tricycle landing gear The configuration of landing gear featuring a nose gear and two main gear beneath the wings.

visual meteorological conditions (VMC) Combinations of visibility, precipitation, and clouds that do not limit flying to certified pilots only. weight One of the four forces of flight, weight is the force caused by tendency of any mass to move toward the earth; weight opposes lift. wind shear A change in wind direction or speed. Can produce swirling, turbulent air currents that can be hazardous to aircraft.