Descriptionary

torque the left-turning twisting motion of an air­craft caused by the right-turning propeller, compen­sated by special rigging automatically, but corrected only manually in some aircraft above cruise speed.

turboprop a turbojet engine connected with a pro­peller.

turbulence disturbed air.

VTOL vertical takeoff and landing aircraft; any air­craft, such as a helicopter, with the capability of lift­ing straight up into the air.

wind shear a rapid change of wind direction or speed affecting airflow over the wings, extremely haz­ardous to aircraft low to the ground.

Aircraft

Balloons

aeronaut balloon pilot or passenger.

aerostation the art of operating a lighter-than-air craft.

altimeter device that measures the altitude of an aircraft by sensing differences in air pressure.

anemometer device that measures wind speed.

apex the top of a balloon.

apex rope rope attached to the top of the balloon used during inflation to control the balloons move­ment; also known as a crown line.

appendix sleeve at the bottom of a balloon where the balloon is filled and through which expanding gas escapes.

attitude the balloon's position relative to the horizon.

ballast disposable weight, usually in the form of sandbags, used to maintain altitude or to slow a descent.

balloonmeister authority responsible for the safe operation of ground-based balloon activities.

basket the basket that carries the aeronauts, con­trols, and fuel; also known as a gondola.

blast-off high-speed liftoff used in windy conditions.

blast valve high-pressure fuel valve.

blimp an airship.

burner unit that burns propane gas to heat the enve­lope of the balloon.

ceiling distance between the ground and cloud cover.

chase crew crew members who assist in the launch and chase the balloon in flight to aid in its landing.

deflation port panel of the upper envelope that detaches to allow hot air to escape to aid in deflation.

dirigible a powered balloon with directional controls.

envelope interior balloon fabric that contains the hot air.

equator area of the balloon's greatest girth. gondola see basket.

gore length of balloon fabric tapering at the end to form sections when sewn to other gores.

helium nonflammable lighter-than-air gas.

hydrogen flammable lighter-than-air gas.

mouth the opening at the base of a balloon.

pyrometer instrument that displays the temperature of the hot air near the top of the balloon.

redline temperature the hottest temperature a bal­loon fabric can withstand without damage.

rip line a line that is pulled to open the deflation port.

sink rate of descent.

sparker device for igniting the burner's pilot light.

telltale heat-sensitive material near the top of a bal­loon providing a warning of dangerously high tem­peratures.

tether anchor line.

thermal rising column of warm air.

variometer device that measures vertical airspeed or the rate of climb or descent.

Blimps

ballast bags 50-pound bags hung from a ring encir­cling the car to help maintain proper weight when loads are light.

ballonets fitted within the large gas bag, two smaller bags that are filled with air to add weight or emptied of air to subtract weight.

bite the volume of air propeller moves, according to the propeller's pitch and speed.

blimp a nonrigid dirigible.

car attached to the underside of the gas bag, the gondola that carries the pilot, passengers, controls, fuel tanks, and other equipment.

Dacron the rubberized fabric a blimp's gas bag is made from.

dirigible any steerable, lighter-than-air craft.

gas bag the large, helium-filled bag that provides lift.

gondola the car.

hangar a large building where a blimp is inspected and maintained.

helium the lighter-than-air gas that fills the gas bag.

mast a large post to which the nose of a blimp is attached when parked or moored on the ground. The mooring mast.

nose lines lines leading from the nose, used by ground crew to stabilize the blimp during takeoffs and landings.

riggers ground crew work on a blimp's fabric and ropes.

rigid a dirigible having a fabric cover stretched over a rigid framework that is filled with individual gas cells.

trim to balance the blimp in flight by adjusting the amount of air in the ballonets.

wind sock the conelike sock erected on a landing field to indicate wind direction.

zeppelin a large, cigar-shaped dirigible having a rigid body.

Helicopters

autorotation an unpowered descent in which the rotor blades are rotated by air currents alone.

clutch the control used to engage and disengage the rotors from the engine to allow autorotation.