Why understanding aviation terminology matters
How to Use This Glossary Effectively
Essential Terms Related to Airport Operations
Slot (airport slot):
Time-specific permission to use an airport's infrastructure for takeoff or landing. Congested airports like London Heathrow, Paris Charles de Gaulle, or Frankfurt impose coordinated slot systems. Obtaining a slot depends on availability and can influence charter flight schedules. Requests must be submitted several weeks in advance for saturated airports. A flight without confirmed slot risks delays or redirections to secondary airports.
Slot coordination:
Administrative process managed by an airport coordinator who allocates time slots according to IATA rules. This coordination ensures traffic fluidity and prevents runway and terminal saturation. Scheduled flights often benefit from historic slots, while charter flights must request ad hoc slots. Procurement timelines vary depending on period (high season, special events) and schedule flexibility. An experienced broker anticipates these constraints during planning and can propose alternative schedules or airports to optimize timelines and costs. In some cases, slot coordination requires direct exchanges with airport authorities to secure slots compatible with the client's operational imperatives.
Handling (ground handling):
Set of ground services provided to an aircraft between arrival and departure. Handling includes parking, refueling, baggage loading, cabin cleaning, catering operations, and administrative formalities. These services are billed separately and vary considerably by airport and service level. Business flights often require premium handling with private terminal access and expedited procedures. Handling quality directly influences passenger experience and punctuality. Handling providers often compete at the same airport, enabling price negotiation and selection based on service quality. An established broker maintains privileged relationships with major European handlers to guarantee consistent service across all rotations.
FBO (Fixed Base Operator):
Private terminal dedicated to business aviation, offering premium services and streamlined procedures. FBOs enable direct ramp-side boarding, private lounges, expedited customs processing, and maximum confidentiality. Their use generates additional fees but considerably improves comfort and reduces turnaround times. Most international airports have several competing FBOs with variable service levels. FBO selection can be specified when booking a charter flight.
Parking fees:
Airport charges for aircraft immobilization on the ground. These fees are calculated based on duration, aircraft weight, and sometimes period (differential day/night pricing). Extended positioning between two flights can generate significant costs reflected in the final quote. Some airports apply an initial grace period; others bill from the first hour. Rotation optimization minimizes these fees in multi-leg operations.
NOTAM (Notice to Airmen):
Technical bulletin disseminating urgent operational information to crews and flight planners. NOTAMs report temporary runway closures, ongoing works, airspace restrictions, or procedural changes. Their consultation is mandatory before each flight to ensure safety and regulatory compliance. A late-published NOTAM may impose route or schedule modifications. Brokers monitor these publications to anticipate impacts on planned operations.
Over-flight permits:
Mandatory administrative authorizations to cross certain countries' airspace. These permits are required even without landing and primarily concern countries outside the European Union, notably in Africa, Asia, and the Middle East. Procurement timelines vary from hours to several weeks depending on countries and can significantly influence long-haul flight planning. Some states impose substantial over-flight fees that must be integrated into the final quote. An experienced broker manages these administrative procedures in advance and optimizes air routes to minimize permit timelines and costs.
Flight types, certifications, and pricing mechanisms
Empty Leg:
Repositioning flight without passengers, performed to return an aircraft to base or position it for a subsequent flight. These flights generate identical operational costs to commercial flights but can be marketed at reduced rates to partially offset expenses. Empty leg availability is unpredictable and depends on aircraft rotations. Routes and schedules are fixed with limited flexibility. This option suits passengers with significant schedule flexibility accepting strict cancellation conditions.
Ferry flight:
Technical flight without commercial passengers, performed to reposition an aircraft or transfer it between bases. Unlike empty legs, ferry flights are generally not commercialized. They occur during scheduled maintenance, aircraft deliveries, or strategic fleet repositioning. These flights respect identical safety standards as commercial flights but with minimal crew. Their existence indirectly influences aircraft availability and pricing in certain regions. Ferry flights may also be necessary after major technical inspections or when transferring an aircraft to a new owner or lessee. Planning these flights requires precise coordination with aviation authorities and maintenance services to ensure regulatory compliance.
Positioning flight:
Preliminary flight allowing an aircraft to reach the client's departure airport. This flight is necessary when the assigned aircraft is located in another region at request time. Positioning fees are generally reflected in the overall quote, unless commercialization as empty leg is possible. A locally based aircraft eliminates this surcharge and reduces mobilization delays. Fleet geographical distribution therefore directly influences final pricing structure.
AOC (Air Operator Certificate):
Certification issued by a national aviation authority authorizing a company to commercially operate aircraft. The AOC attests to compliance with safety, maintenance, crew training, and operational procedure standards. Each air operator must hold a valid AOC corresponding to operated aircraft types and geographical operation zones. Brokers like Artheau Aviation do not hold AOCs but collaborate exclusively with certified operators. Systematic AOC verification ensures regulatory compliance and operational safety. AOCs are subject to regular audits and can be suspended or revoked for non-compliance, which is why professional brokers maintain constant monitoring of their operator partners' status.
ACMI (Aircraft, Crew, Maintenance, Insurance):
Lease formula including aircraft, complete crew, maintenance, and insurance. The charterer client provides only fuel and assumes airport charges. This formula is common in commercial aviation for seasonal needs or temporary capacity reinforcement. European regulations strictly frame ACMI to preserve competition and social standards. A broker can structure compliant ACMI solutions for cargo operations or specific passenger programs.
Wet lease:
Aircraft lease with crew and maintenance included, formula similar to ACMI but with more complete operational services. The lessor ensures technical operations while the lessee retains commercial responsibility. This formula enables rapid fleet unavailability mitigation or new market testing without capital investment. Contract duration varies from weeks to months depending on needs. Regulatory implications differ by geographic zone and require prior legal analysis.
Dry lease:
Aircraft-only lease without crew or operational services. The lessee assumes complete operation: crew recruitment, maintenance, insurance, certifications. This formula addresses operators already possessing necessary infrastructure and seeking temporary capacity increase. Regulatory implications are complex and often require specific authorization procurement. Dry lease remains marginal in ad hoc charter but common in established carrier fleet strategies.
Block hours:
Total duration between when the aircraft starts moving for departure and when it stops after landing. This measure includes ground taxi, actual flight time, and arrival procedures. Block hours constitute the standard billing basis in business aviation. They differ from pure flight time and are always higher. Quotes systematically specify this calculation method to ensure pricing transparency.
Minimum block time:
Minimum billable duration imposed by the operator, regardless of actual flight time. This minimum covers fixed crew and aircraft mobilization costs. It generally varies between one and three hours depending on aircraft type and commercial policy. A very short flight may thus be billed on a basis exceeding actual time. This standard clause protects operational profitability on short-distance flights.
Repositioning costs:
Fees generated by positioning and empty return flights of the aircraft. These costs are calculated in block hours and added to the main commercial flight rate. Their amount depends on the distance between aircraft base and client departure airport. A locally based aircraft eliminates these fees and improves pricing competitiveness. Brokers optimize these parameters by selecting the best geographically positioned aircraft and exploring possibilities of commercializing empty segments as empty legs. In some cases, intelligent combination of multiple client requests enables creation of optimized rotations significantly reducing repositioning costs for all parties.
