A
- AOC (Air Operator Certificate)
- The certificate issued by a national aviation authority that allows a company to carry passengers for hire. The AOC holder is the operator: it is responsible for the crew, the airworthiness of the aircraft and the conduct of the flight.
- AOG (Aircraft on Ground)
- A technical fault that keeps an aircraft on the ground until it is repaired. A good charter agreement states what happens if the booked aircraft goes AOG — usually a replacement of the same class from the operator or the wider market.
- APD (Air Passenger Duty)
- A UK tax on passengers departing from UK airports. The higher rate currently applies to aircraft of 20 tonnes or more with fewer than 19 seats; from 1 April 2027 it is due to cover business jets of 5.7 tonnes or more.
- ARGUS rating
- An independent rating of charter operators. ARGUS Gold, Gold Plus and Platinum assess safety history, pilot experience and, at the higher levels, an on-site audit of the operator’s safety management.
B
- Block time
- The time from the moment the aircraft moves off its stand to the moment it stops at the destination, including taxiing. Some operators price by block time and others by flight time; the quote states which. Block time is slightly longer than airborne flight time.
C
- Category C airport
- An airport with demanding terrain, approaches or local procedures, where crews need specific training or a briefing before they may operate there. Samedan, serving St. Moritz, is a well-known example in the Alps.
- Charter agreement
- The contract for the flight. It names the operator, aircraft, schedule, price, payment terms, cancellation charges and what happens if the aircraft becomes unavailable.
- Charter broker
- A company that arranges charter flights for clients with operators that hold an AOC. The broker does not fly the aircraft; the operator remains responsible for the flight.
- Crew duty limits
- Rules that cap how long pilots may be on duty and set minimum rest. They decide whether one crew can fly an itinerary or whether a second crew or an overnight stop is needed.
- Curfew
- Hours during which an airport is closed or restricted for noise reasons. Night curfews at many European city airports fix the latest possible arrival.
D
- Daily minimum
- The minimum number of flight hours an operator bills for each day the aircraft flies, commonly one to two hours.What moves the price
- De-icing
- Removing ice and applying protective fluid before a winter departure. It is usually passed on at cost and can reach several thousand dollars on a large aircraft.
E
- eAPIS
- The US Customs and Border Protection system for advance passenger information. For private flights to or from the United States, the manifest must be filed no later than 60 minutes before departure.
- EASA
- The European Union Aviation Safety Agency. Commercial passenger flights by European operators follow its Air Operations rules for commercial air transport (Part-CAT) and fly on an AOC issued by a national authority.
- Empty leg
- A positioning flight — the aircraft would otherwise fly without passengers — offered at a reduced rate. The route and airport pairing are fixed, and changes on either side are frequent. Empty legs suit flexible schedules; when timing is critical, a booked charter is more predictable.Browse current empty legs on EmptyJet
F
- FBO (Fixed-Base Operator)
- A private terminal for business aircraft, with a lounge, passport and security control, fuelling, parking and ground handling. Passengers usually walk or drive to the aircraft from the FBO instead of using the main terminal.
- FET (Federal Excise Tax)
- A 7.5% US tax on the price of commercial air transportation within the United States, plus a per-segment fee. It applies to domestic charter flights; international flights pay separate international arrival and departure taxes.
- Flight time
- The time an aircraft is airborne, from take-off to landing. It is shorter than block time, which also counts taxiing.
- Fractional ownership
- Buying a share of an aircraft managed by a provider, with a monthly fee and an hourly rate on top. It typically suits around 50 to 400 flight hours a year.Charter, card or ownership
G
- GAT (General Aviation Terminal)
- A terminal reserved for private and business flights, run by the airport or by an FBO.
- Ground handling
- Services an aircraft needs on the ground: marshalling, baggage, fuelling coordination, catering delivery and passenger escort. It is provided by a handling agent or an FBO.
H
- Heavy jet
- A large-cabin business jet with 10 to 14 seats and a range of roughly 7,400–8,300 km, such as the Challenger 650, Falcon 900EX or Gulfstream G450. It flies transatlantic city pairs non-stop.Heavy jets in detail
- Hot and high
- Airports at high elevation or in high temperatures, where thinner air reduces engine thrust and lift. An aircraft may have to carry less fuel or fewer passengers, sometimes forcing a fuel stop.
I
- IS-BAO
- The International Standard for Business Aircraft Operations, a voluntary code of practice from the International Business Aviation Council. Operators are audited at Stage 1, 2 or 3 depending on how mature their safety management is.
J
- Jet card
- A prepaid or committed-hours programme that fixes an hourly rate for a class of aircraft. Most programmes guarantee availability at an agreed notice period, with restrictions on peak days.
L
- Light jet
- A business jet with six to eight seats and a range of about 3,700 km, such as the Phenom 300E or Citation CJ3+. It is the workhorse of short and medium continental charter.Light jets in detail
M
- Midsize jet
- A business jet with seven to nine seats, a cabin height around 1.7 m and an enclosed lavatory, such as the Citation XLS+. It flies about 3,400–4,700 km.Midsize jets in detail
- MTOW (Maximum Take-Off Weight)
- The heaviest weight at which an aircraft is certified to take off. Airport fees, some taxes and runway limits are set by it.
N
- Nautical mile (nm)
- The unit of distance used in aviation, equal to 1.852 km. Aircraft ranges are usually published in nautical miles.
- NBAA IFR range
- A standardised range figure used by manufacturers, calculated with set fuel reserves in still air and with a light payload. Real charter range with a full cabin and headwinds is shorter.
O
- Operator
- The company that holds the AOC and flies the aircraft. It employs or contracts the crew and is legally responsible for every flight it operates.
- Overnight (crew)
- Hotel, meals and allowances for the crew when the aircraft stays away from its base overnight, usually quoted per night.
P
- Part 135
- The US rules for on-demand commercial air carriers. On-demand charter within the United States is flown by operators holding a Part 135 (or Part 121) certificate.
- Part 91
- The US general operating rules, which cover non-commercial flying such as an owner using their own aircraft. Carrying passengers for compensation generally requires a commercial certificate, such as Part 135.
- Passenger manifest
- The list of everyone on board, passengers and crew, with passport details. It is required for international flights and for security screening at the FBO.
- Positioning flight
- A flight without passengers that brings the aircraft to the departure airport or back to base, also called a ferry flight. Its cost is usually part of the charter price; when it is sold to passengers, it becomes an empty leg.How positioning affects price
- PPR (Prior Permission Required)
- Airports where every movement needs advance approval from the airport operator. Common at smaller airfields and in peak seasons.
S
- Slot
- Permission to land or take off at a specific time at a coordinated airport. London City, Nice and many busy hubs require slots; at peak times they are scarce, which is why early confirmation matters.
- Stand-up cabin
- A cabin tall enough to walk upright, generally about 1.83 m and above, typically from the super midsize class upward.
- Super midsize jet
- A business jet with eight to ten seats, a flat floor and a stand-up cabin of about 1.83 m, such as the Challenger 350 or Praetor 600, flying about 5,900–7,400 km.Super midsize jets in detail
T
- Tail number
- The aircraft’s registration, painted on the fuselage. A quote that names the tail number identifies the exact aircraft, its age and its operator.
- Technical stop
- A landing only to refuel, usually without passengers leaving the aircraft. It is planned when the distance or a hot and high departure exceeds the aircraft’s practical range.
- Turboprop
- A propeller aircraft driven by a turbine engine, such as the Pilatus PC-12. Slower than a jet but able to use short, unpaved and mountain airfields.Turboprops in detail
U
- Ultra long range (ULR)
- The longest-range business jets, such as the Global 7500 or Gulfstream G650 and G700, flying about 11,100–14,350 km non-stop with up to 19 seats.Ultra-long-range jets in detail
V
- VAT on charter
- In the European Union, domestic flights generally carry VAT at the national rate, while international flights are usually zero-rated. Rules differ by country, so VAT is shown separately in a quote.
- Very light jet (VLJ)
- The smallest jets, such as the Phenom 100 or Citation Mustang, seating four and certified for single-pilot operation. Suited to short city pairs.Very light jets in detail
- VIP airliner
- An airliner such as the ACJ319 or Boeing BBJ fitted out with lounge, dining and bedroom. Most are configured for up to 19 passengers, because above 19 passenger seats certified cabin crew are required.VIP airliners in detail
W
- Wet lease (ACMI)
- An arrangement in which one operator supplies the aircraft, crew, maintenance and insurance to another. The supplying operator keeps operational control.
- Wyvern Wingman
- An operator standard from the safety auditor Wyvern, awarded after an on-site audit of safety management, training and operational control.