Rules governing flight procedures during limited visibility or other operational constraints. Under IFR, pilots must file a flight plan and fly under the guidance of radar.
The set of rules that govern instrument flight. Filing IFR or departing IFR means that the pilot is operating under those rules. Aircraft are much more closely controlled under those rules and are permitted to fly through clouds as Air Traffic Control is keeping aircraft separated. To "be IFR" is to operate under these rules under a clearance from ATC. Sometimes pilots (including me) say IFR when we mean IMC, or refer to a field as "being IFR." When a field is IFR, it means that only departures and arrivals under IFR (or in some cases special VFR) are legal.
Rules governing flight in certain limited visibility and cloud conditions. Under IFR, an aircraft is required to be in contact with air traffic control facilities and is separated by ATC from all other IFR aircraft.
Federal Aviation Regulations rules that govern the procedures for conducting instrument flight (FAR Part 91).
Set of rules, guidelines, and procedures that the Federal Aviation Administration (FAA) has established for pilots to operate aircraft in marginal weather conditions, usually defined as ceilings below 1,000 feet/ visibility less than 3 miles.
A set of regulations set down by the U.S. Civil Aeronautics Board to govern the operational control of aircraft on instrument flight. The abbreviation of this term is seldom used to denote the rules themselves, but is in popular use to describe the weather and/or flight conditions to which these rules apply.
A set of rules governing the conduct of flight under instrument meteorological conditions (IMC). abbreviation: IFR Fr: règles de vol aux instruments
A regulatory term describing a flight which may be conducted in conditions where the pilot cannot see outside the aircraft (e.g. in cloud and fog) and must fly only by his instruments. Compare to Visual flight rules.
That portion of the Federal Aviation Regulations (FAR Part 91) specifying the procedures to be used by aircraft during flight in instrument meteorological conditions. These procedures may also be used under visual conditions and provide for positive control by ATC. (See also VFR.)
Refers to the general weather conditions pilots can expect at the surface and applies to the weather situations at an airport during which a pilot must use instruments to assist take off and landing. IFR conditions for fixed wing aircraft means the minimum cloud ceiling is greater than 500 feet and less than 1,000 feet and/or visibility is greater than 1 mile and less than 3 miles.
Instrument Flight Rules (IFR) are a set of regulations and procedures for flying aircraft without the assumption that pilots will be able to see and avoid obstacles, terrain, and other air traffic; it is an alternative to visual flight rules (VFR), where the pilot is primarily or exclusively responsible for see-and-avoid. Since navigation and control of the aircraft under IFR is done by instruments, flying through clouds is allowed; under VFR it is not.
