Glossary of Terms - Private Aviation

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AIR AMBULANCE Air charter of a private jet, helicopter or turbo-prop certified to provide air transport to medical patients.

AIR CHARTER Act of renting or leasing a jet or plane for transport of cargo or passengers.

AIR CHARTER AGENT One who is contracted on behalf of the end user of the charter flight. A charter agent works to ensure fair market value, reasonable safety measures are followed and to provide flexibility and options for the purchaser of the air charter flight.

AIR CHARTER OPERATOR Responsible for the licensing, maintenance, safety and operations of the air charter company. The air charter operator is not always the owner of the luxury jet, business jet or private jet that is available for charter.

AIR TRAFFIC CONTROLLER The service to pilots that promotes the safe, orderly and expeditious flow of air traffic. Usually each country operates its own Air Traffic Control service. In the UK, Air Traffic Control services are provided by NATS.

AIRCRAFT The equipment used or intended to be used for flight. An aircraft is any machine that gains support or lift from the reaction of the air.

AIRPORT An area that is used for takeoffs and landings of aircrafts. Airports can be on land or water.

AIRSPEED Speed of an aircraft relative to its surrounding air mass.

AIRWAY DISTANCE The actual (as opposed to straight line) distance flown by the aircraft between two points, after deviations required by Air Traffic Control and navigation along published routes.

ALTERNATE AIRPORT Alternate airport is an airport that allows an aircraft to land when landing at the intended airport is not possible (typically for safety reasons).

ALTITUDE Vertical distance between an object and mean sea level.

AOC An Air Operator's Certificate is the approval granted from a national aviation authority to an aircraft operator to allow it to use aircraft for commercial purposes. This requires the operator to have personnel, assets and systems in place to ensure the safety of its employees and the general public. The certificate will list the aircraft types and registrations to be used, for what purpose and in what area - specific airports or geographic region.

APRON Hard-surfaced or paved area around a hangar. See also Ramp.

APPROACH (departure) CONTROL Radar-based Air Traffic Control, associated with the tower at larger airports. Provides traffic separation services from outside the immediate airport area to a distance of about 40 miles.

AVIATION The operation, development, production and use of aircraft.

AVIONICS The electronic control systems airplanes use for flight such as communications, autopilots, and navigation.


BLOCK FLYING TIME Time between an aircraft first moving from its parking place for the purpose of taking off until it comes to rest on the designated parking position and until all engines are stopped.

BLOCK RATES Lower contract rate for scheduling significant amounts of air charter time in advance on a prearranged agreement.

BLOCK SPEED The average speed over a specific distance "block-to block", or door-to-door with respect to the airport gate.

BUSINESS JET CHARTER An aircraft that is chartered for the purpose or use in business transportation.


CARBON CREDIT Key component of national and international emissions trading schemes. They provide a way to reduce greenhouse effect emissions on an industrial scale by capping total annual emissions and letting the market assign a monetary value to any shortfall through trading. Credits can be exchanged between businesses or bought and sold in international markets at the prevailing market price. Credits can be used to finance carbon reduction schemes between trading partners and around the world.

CARBON EMISSIONS The principal greenhouse gas emission. Carbon is largely thought to be the most dangerous greenhouse gas.

CARBON OFFSET Monetary contributions to renewable energy research and production projects, designed to reflect and mitigate the user's own greenhouse gas emissions eg through air travel.

CARDINAL ALTITUDE Thousand foot flight levels or altitudes.

CATERING A service provided for luxury jet charters. Catering is the provision of in-flight meals.

CEILING The heights above the earth's surface of the lowest layers of clouds or obscuring phenomena that is reported as broken, overcast, or obscuration, and not classified as thin or partial.


CHARTER CARD Pre-paid air charter plan, either for a block of charter hours at a pre-defined fee, or a set debit balance in dollars.

COMMERCIAL FLIGHT A "commercial" flight is when the customer has paid for a commercial charter of that aircraft. The rules for commercial flights are more stringent than private flights and include limitations on crew duty hours, runway length and other safety considerations. For commercial private jet charter the minimum stopping distance for the aircraft is multiplied by 1.6, to create the minimum landing distance required (LDR).

COMMUTER OPERATOR A regional, scheduled airline. In this book limited to that operator with adequate fleet capacity as to be available of charter. Not all commuter airlines charter, because of the limitations of aircraft and crew availability.

CONTRAILS Streaks of condensed water vapour created in the air by aircraft flying at high altitudes; aka vapour trails.

CONTROLLED AIRSPACE An airspace of defined dimensions within which Air Traffic Control service is provided to IFR flights and to VFR flights in accordance with the airspace classification.

CORPORATE OPERATOR A company flight department which has earned a "Part 135" certificate to carry passengers for compensation.

CROSSWIND Winds blowing perpendicular or not parallel to the runway or the aircrafts flight path.

CRUISE SPEED The normal speed attained at altitude once the aircraft is no longer climbing and is en route.

CRUISING ALTITUDE A level altitude maintained by an aircraft while in flight.


DEAD HEAD The term used when referring to a leg of an air charter with no cargo or no passengers. This is commonly the return leg of an air charter but could also be the repositioning of an air charter.

DECISION HEIGHT When flying an aircraft, the height at which a decision must be made during an instrument approach to either continue the approach or to execute a missed approach.

DEMURRAGE refers to the charges that are levied by an operator when a charterer keeps an aircraft after the completion of the flight. For example, if an aircraft is chartered for two flights with a week intervening, an aircraft may remain or lay over at the destination. The charterer will pay demurrage charges for every day that this aircraft remains at the charterer's destination without returning home.

DEPRECIATION Method to account for assets whose value decrease over time because of factors such as age, wear or market conditions.

DOUBLE ROUND TRIP Occurs when an air charter itinerary is designed such that it is more costly to keep the plane away from base than it would be to return home empty the report for pick up to complete the air charter itinerary.

DUTY TIME A pilot or crew member is logging duty time whenever he is serving in any capacity. There are safety restrictions on duty time to ensure pilots and crew are sufficiently rested.


EFIS (Electronic Flight Information Systems) Glass cockpit avionics that integrate all flight parameters into one optimized instrument. These modern systems offer enhanced reliability, reduced weight, simplified installation and overall cost savings.

EGPWS (Enhanced Ground Proximity Warning System) Uses aircraft inputs such as position, attitude, air speed and glide slope, which along with internal terrain, obstacles, and airport databases predict a potential conflict between the aircraft's flight path and terrain or an obstacle.

ELT (Emergency Locator Transmitter) A radio transmitter activated automatically by the impact of an accident. Emits a warbling tone on the international emergency frequencies of 121.5 MHz, 243 MHz and (newer models) 406 MHz. ELT signals can be received by nearby FAA facilities, aircraft overhead, and search and rescue (SARSAT) satellites.

EMPTY LEGS A re-positioning flight where the aircraft is flying empty. Chartering an empty leg can cost significantly less than a full-price charter.

EXECUTIVE JET CHARTER An aircraft that is chartered for the purpose or use in the transportation of executives. Typically the aircrafts that are chartered are midsize jets.


FAA (Federal Aviation Administration) The US Department of Transportation's agency for aviation in the United States. In addition to regulating airports, aircraft manufacturing and parts certification, aircraft operation and pilot certification, the FAA operates Air Traffic Control, purchases and maintains navigation equipment, certifies airports and aids airport development, among other activities.
FBO Fixed Base Operator - provides ground services for air charter clients such as: onsite mechanic, fuel service, catering, ground transportation and other services.

FEATURED CHARTER The chartering of a specific aircraft to a specific destination. Featured charters often include hotel accommodations, luxury car rentals, golf and spa packages etc.

FERRY FLIGHT A flight for the purpose of returning an aircraft to base, delivering an aircraft from one location to another, moving an aircraft to and from a maintenance base.

FLEET MANAGER A commercial aviation entity developed to subcontract the maintenance and operation of corporate aircraft, which are often chartered out to the general public.

FLIGHT PLAN Filed with an Air Traffic Control Facility a flight plan is the specific information regarding the flight or intended flight of an aircraft.

FLIGHT TIME Flight time is the time the aircraft is in flight. The point of time between take off and touchdown.

FMS (Flight Management System) A regional office of the United States Federal Aviation Administration that concentrates on enforcing regulations.

FOD Foreign object debris. FOD refers to anything on the runway that may cause hazards to aircrafts or people on the ground.

FRACTIONAL OWNERSHIP The purchase of a "share" of an aircraft. Fractional owners are guaranteed access to an aircraft but not necessarily the same one each time. They usually pay a fixed monthly maintenance fee as well as an hourly fee.

FUEL SURCHARGE A charge for the increased price of fuel to cover fuel price increases.

FUSELAGE An aircraft's main body structure housing the flight crew, passengers, and cargo.


GENERAL AVIATION Refers strictly to private aviation; not for hire.

GLOBAL POSITIONING SYSTEM GPS. Satellite positioning, velocity and time system. Highly accurate navigation aid.

GPWS (Ground Proximity Warning System) System designed to alert pilots if their aircraft is in immediate danger of flying into the ground. Also called Ground-Collision Warning System.

GREAT CIRCLE DISTANCE The shortest distance between two points on a globe. All distances shown in distance tables in the Air Charter Guide are "great circle distance".

GROUND SPEED The speed of an aircraft relative to the surface of the earth.

GROUND TRANSPORTATION A service provided for luxury jet charters before or after the flight. Ground transportation can be limo service or luxury car rental.


HANGAR An enclosed structure for housing aircraft. Originated with lake-based floating homes of the original German Zeppelins in which they were "hung" from cables.

HEAVY JET An aircraft with a minimum takeoff weight of 255,000 lbs.

HELICOPTER A rotor driven aircraft that uses vertical axes with pitched blades to generate lift and stability.

HELIPAD A helipad is used for takeoffs, landings and occasionally for parking of helicopters.

HELIPORT The area of land or water used for the landings and takeoffs of helicopters, the buildings, structures and grounds.

HORSE POWER The motive energy required to raise 550 lbs. one foot in one second, friction disregarded.


IATA Code International aviation codes for international airports

ICAO (International Civil Aviation Organization) An agency of the United Nations. The IACO is charged with the development of principles and techniques of international air navigation.

IFR (Instrument Flight Rules) Rules of the road for flights permitted to penetrate clouds and low visibility conditions by reference to cockpit flight instruments and radio navigation. Aircraft must be equipped and pilots qualified and current for IFR flight. Flight plans and ATC clearances are required. Flights are monitored and traffic separated by Air Traffic Control, usually by radar.

ILS (Instrument Landing System) A precision instrument approach system utilizing radio transmitters at the runway ends which provide precise left-right and up-down indications to the pilot permitting aircraft to land during periods of low ceilings or poor visibility.

INDICATED AIR SPEED The speed displayed by the aircraft's air speed indicator device.

INSTRUMENT METEROLOGICAL CONDITIONS Conditions such as visibility, distance between clouds, ceiling level that does not meet the standard for visual meteorological conditions.

INTERNATIONAL AIRPORT Any airport designated by its contracting state to carry out the duties of customs and immigrations along with other duties.


JET CHARTER Act of hiring crew; leasing an aircraft for the purpose of private air transportation.

JET CHARTER BROKER An intermediary who facilitates the leasing or purchasing of air charter. See also Private Jet Broker.

JET STREAM High altitude, High Speed winds that in the United States blow from west to east.

JOINT OWNERSHIP Purchase or lease of a complete aircraft by a relatively small number of owners, often through a partnership or limited liability corporation.


KNOT (nautical mile per hour) Most common measure of aircraft speed equaling 6,080 feet or about 1.15 miles.


LAYOVER A night spent in the middle of the trip in a city other than home base for the aircraft and crew.

LEG A single direction of travel between two points. For an air charter itinerary a leg could be represented by repositioning and fuel stops.

LIFT An aircraft charter engaged for cargo or passenger transport.
LUXURY JET CHARTER The chartering of an aircraft that is not for pleasure. It provide 5 star catering, ground transportation, and lavish accommodations. Luxury jet charters typically are in excess of needs.


MATCH SPEED The ratio of ones true airspeed to the speed of sound

MEDEVAC Medical evacuation - the term commonly applied to an aircraft used to transport injured patients to hospital. See also Air Ambulance.


NATIONAL AIRSPACE SYSTEM National Airspace System is the network of airspace, navigational services facilities and equipment.

NAUTICAL MILE National Airspace System is the network of airspace, navigational services facilities and equipment.

NAVAIDS Navigational aid is any form of device that guides a pilot and his aircraft from one area to another. There are many different kinds of Navaids in use to provide guidance, location, and direction, the most popular being the Global Positioning System (GPS) but the term can also apply to a map, a beacon or a compass.

NAVIGATION known to be the process of recording, planning and controlling the movement of an aircraft or vehicle from one point to another.

NATS Provider of Air Traffic Control services to aircraft flying in UK airspace and over the eastern part of the North Atlantic.

NBAA National Business Aviation Association.

NONTOWERED AIRPORT An airport without a control tower


OPERATOR Responsible for the licensing, maintenance, safety and operations of one or more private charter aircraft. The operator is not always the owner of the luxury jet, business jet or private jet that is available for charter.

ONE-WAYS The air charter of an aircraft for a particular leg of an existing air charter itinerary.


PATTERN The path of aircraft traffic around an airfield, at an established height and direction. At tower-controlled fields, Air Traffic Controllers supervise the pattern by radio (or in non-radio or emergency conditions by red and green light signals.

PAYLOAD Anything that an aircraft carries beyond what is required for its operation during flight, theoretically cargo or passengers from which revenue is derived.

PILOT IN COMMAND The pilot that is responsible for safety and operations of the aircraft during flight.

POINT TO POINT PRICING Usually occurs when one charters a jet from a location other than where that aircraft is based; also known as a transient aircraft charter. Point to point pricing is typically the result of an empty leg being chartered for a portion of the primary routing of the original air charter itinerary.

POSITIONING Ferrying aircraft for departure from other than originating airport.

PRECIPITATION Water particles that fall from the atmosphere and reach the surface of the earth.

PREFFERED VENDORS Air Charter Agents, Jet Charter Brokers and Charter Jet Operators develop a list of Air Charter vendors for each region that they service. Preferred vendors are the vendor of choice for supplemental lift.

PRIVATE AIRPORT An airport used by general aviation and private aviation but is ineligible for use by scheduled airline travel.

PRIVATE FLIGHT A "private" flight is when an owner of the aircraft (or one of their friends or family) are using the aircraft for private use. No money changes hands for the use of the aircraft. (As opposed to a COMMERCIAL FLIGHT)

PRIVATE JET An aircraft owned by a private person or organization.

PRIVATE JET BROKER An intermediary who facilitates the hire of a private aircraft, usually comparing options from operators. See also Jet Charter Broker.

PRIVATE JET CHARTER Hiring a private jet aircraft for a specific itinerary - as opposed to ownership or fractional ownership of an aircraft.

PROHIBITED AREA An airspace area where flight is prohibited except by prior arrangement with the controlling agency.


Q There's no queues when you book an aircraft with PrivateFly! If you want to submit an aviation term for the letter Q please contact us.


RADAR Transmission of a radio pulse that provides information on range and elevation of objects in the path of transmitted pulses.

RADIO A device used by aircraft for the purpose of communication.

RAMP The apron or open "tarmac" in front of an FBO or terminal facility. This space is busy, used for deplaning, parking of aircraft, etc.

RELEASE TIME A departure time restriction issued to a pilot by ATC (either directly or through an authorized relay) when necessary to separate a departing aircraft from other traffic.

REPOSITIONING TIME The travel time for charter aircraft traveling to or from base en- route to the departure or from the destination of the particular air charter trip.

RESTRICTED AREA Airspace that (when "Active" or "Hot") usually excludes civilian aircraft. Examples: airspace for rocket flights, practice air-to-air combat or ground-based artillery practice. Temporary restricted areas are established for events such as forest fires, natural disasters or major news stories. The "controlling agency" or FAA may authorize flight through a restricted area.

RUDDER Aircraft control surface attached to the rear of the vertical stabilizer (fin) of the aircraft tail. Forces the tail left or right, correspondingly "yawing" the aircraft right or left. Rudder movement "coordinates" with the banking of wings to balance a turn. Controlled by left and right rudder (foot) pedals.

RUNWAY Smooth area prepared for landings and takeoffs of aircrafts.


SCHEDULED AIR TRANSPORTATION Airline Transportation requires the FAA Part 121 certificate.

SEE AND AVOID The FAA requirement that all pilots are ultimately responsible for separation from other aircraft when visual conditions permit spotting traffic. Even IFR flights when operating in visual weather conditions or VFR flights being issued radar advisories are responsible for visual scanning to see-and-avoid other traffic.

SIGMET An advisory issued in times of severe weather that is significant to the safety of ALL aircraft.

SPEED OF SOUND The speed of sound is equal to 769 mph.

SPORT JET CHARTER The chartering of an aircraft for the purpose of transporting members of sports teams to sporting events.

STAGE LENGTH The distance of the air charter client's itinerary.

STATUTE MILE A unit of length equal to 5,280 feet.


TAIL NUMBER An airplane's registration number.
TAIL WIND Winds that are more than 90 degrees to the longitudinal axis of the runway.

TARMAC An airport surface paved with the substance, especially a runway or an apron at a hangar.

TAWS (terrain awareness and warning system) An advanced type of GPWS that provides the flight crew earlier aural and visual warning of impending terrain, forward looking capability and continued operation in the landing configuration.

TAXI TIME Taxi time is the time the aircraft is in transit to the runway up to the point of take off.

TCA (terminal control area) A volume of controlled airspace set up at the confluence of airways in the vicinity of one or more major airports to protect traffic climbing out from and descending into the airports.
TCAD A proprietary low cost anti-collision system detecting and alerting pilots to nearby transponders but not providing evasive instructions or coordination with other aircraft.

TCAS (traffic alert and collision avoidance system) A cockpit system to detect other transponder-equipped aircraft, alert pilots, and command/coordinate evasive action between aircraft.

THIRD PARTY VERIFICATION Refers to the verification of safety, maintenance and operations by an independent auditor.

TRAFFIC PATTERN A standard rectangular flight pattern around the landing runway at an airport. Includes 45-degree or crosswind entry to the rectangle, with downwind, base and final legs as sides of the rectangle. Standard are 90-degree left turns around the rectangle (non-standard right-hand traffic pattern is noted in Airport Facility Directories) with downwind flown at a specified altitude, usually 1,000 or 1,500 feet above the airport elevation. At airports with a control tower; the pattern may be modified or short-cut according to ATC instructions.

TRANSPONDER An airborne transmitter that responds to ground-based interrogation signals to provide Air Traffic Controllers with more accurate and reliable position information than would be possible with "passive" radar; may also provided Air Traffic Control with an aircraft's altitude.

TRUE AIR SPEED Takes wind out of the picture. True air speed is the speed of an aircraft relative to undisturbed air.

TURBINE Engine that uses compressed air to generate thrust to spin a metal shaft inside the motor. Turbines are vital components in jet engines and also power turboprop aircraft.

TURBO JET AIRCRAFTS Aircrafts with jet engines that operate turbines which operate air compressors.

TURBO POP AIRCRAFT An aircraft with a jet engine powering a turbine and propeller.


UNICOM (universal communication) A common radio frequency (usually 121.0 mHz) used at controlled (non-tower) airports for local pilot communication. UNICOM is also used by a Fixed Base Operator for general administrative uses, including fuel orders, parking instructions, etc.


VFR Visual flight rating; does not allow pilots to ascend through cloud cover.

VISIBILITY The ability to see and identify prominent un-lit objects during the day and lit objects of prominence at night.

VISUAL METEROLOGICAL CONDITIONS Conditions such as visibility, distance between clouds and a ceiling that is equal to or better than the specified minimums.

VLJ A VLJ is a Very Light Jet (may also be referred to as entry-level jet) is a small, short-range and jet that can be operated by a single pilot and seats 2-4 passengers.


WAIT TIME The time the aircraft is waiting on the tarmac for the departure of its next leg of the itinerary.

WAKE TURBULENCE Turbulent air condition caused by small, tornado-like horizontal whirlwinds trailing an aircraft's wingtips (wingtip vortices). Wake turbulence associated with larger aircraft flying at slow speeds (as on take-off or landing approach) is the most severe and can cause loss of control for smaller aircraft following close behind. Controllers use defined separation standards to avoid the problem for take-off, landing, approach and departure operations.

WAYPOINT Predetermined geographical position defined relative to other navigational aids.

WEATHER MINIMUMS Lowest (worst) visibility conditions under which an aircraft may legally be flown under visual flight rules. When visibility is less than specified minimums, an aircraft must fly under instrument flight rules or not at all.

WINGLET A small, stabilizing, rudder-like addition to the tips of a wing to control or employ air movement, thereby increasing fuel economy.


X-1 The first aircraft to break the speed of sound in 1946. Piloted by pioneer Chuck Yeager, the aircraft set the benchmark for all future supersonic aircraft.


YAKOLEV AIRCRAFT CORPORATION Often shortened to Yak, this is a seminal Russian aircraft manufacturer responsible for hundreds of aircraft designs over its 80 year history. Many of its Yak 40 models are now available for charter in former Soviet countries as private jets.


ZULU The phonetic pronunciation of the final letter of the NATO phonetic alphabet.

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