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IFR (Instrument Flight Rules)
A set of regulations and procedures for flying aircraft by reference to instruments only, without visual reference to the ground. IFR flight requires an Instrument Rating, an IFR-equipped aircraft, and an ATC clearance.
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- ILS (Instrument Landing System)A precision instrument approach system that provides both lateral (localizer) and vertical (glideslope) guidance to the runway. ILS approaches allow landings in lower visibility conditions than non-precision approaches.
- KnotThe standard unit of speed in aviation, equal to one nautical mile per hour (approximately 1.15 statute miles per hour or 1.852 kilometers per hour). Airspeed, wind speed, and ground speed are typically expressed in knots.
- Load FactorThe ratio of the lift produced by the wings to the actual weight of the aircraft. In level flight, load factor is 1G. During turns, load factor increases — a 60-degree banked turn produces a 2G load factor, doubling the effective weight on the wings.
- LogbookA record where pilots document their flight time, including date, aircraft type, route, conditions (day/night, VFR/IFR), and type of experience (solo, dual, PIC). Accurate logbook entries are required to prove eligibility for certificates and ratings.