An aeronautical vehicle operated for sport or recreational purposes which does not require FAA registration, an airworthiness certificate, nor pilot certification. Primarily single-occupant vehicles, although some two-place vehicles are authorized for training purposes. Operation of an ultralight vehicle in certain airspaces requires authorization from ATC.

Class G Airspace; airspace not designated as Class A, B, C, D or E.

The landing gear of a land-based aircraft, including struts, frames, and wheels.

To land short of a runwway or planned landing spot. Opposite is OVERSHOOT.

A common radio frequency (usually 121.0 mHz) used at uncontrolled (non-tower) airports for local pilot communication.

The slight, upward flow of air just prior to its reaching the leading edge of a rapidly moving airfoil.

Long a point of contest among pilots, there is in reality no such thing as far as the airplane is concerned. Proponents claim that airplanes lose airspeed when turning upwind, while opponents (and the laws of physics) argue that an airplane, like a boat in a river whose speed is only relative to the shore, is unaffected within the movement of an air mass and that it loses only groundspeed.

The weight of crew, passengers, fuel, baggage, and ballast, generally excluding emergency or portable equipment and ordnance.