This glossary highlights operational, commercial, safety, regulatory, maintenance, and cargo terminology used across the Travel, Transportation & Logistics sector. It helps executives and practitioners navigate the specialized language of the Airlines & Air Cargo Practice, from fleet economics and passenger distribution to flight operations and cargo security.
A B C D E F G H I K L M N O P Q R S T U W Z
| A | |
| A4A | Airlines for America: A trade association representing major U.S. passenger and cargo airlines on regulatory, safety, operational, and economic policy matters. |
| AAPA | Association of Asia Pacific Airlines: A regional trade association representing international airlines based in the Asia-Pacific region. |
| ACARS | Aircraft Communications Addressing and Reporting System: A digital datalink system used to exchange operational messages between aircraft and ground systems, including flight plans, weather, maintenance data, and movement reports. |
| ACAS | Airborne Collision Avoidance System: An onboard safety system that detects potential conflicts with nearby aircraft and issues traffic information or avoidance instructions to pilots. |
| ACAS | Air Cargo Advance Screening: A U.S. security program requiring advance shipment data so authorities can assess inbound air cargo risk before loading. |
| ACC3 | Air Cargo or Mail Carrier Operating into the Union from a Third Country Airport: An EU aviation-security designation requiring affected carriers and their overseas cargo operations to meet specified validation and screening controls. |
| ACMI | Aircraft, Crew, Maintenance and Insurance: A wet-lease arrangement in which one operator supplies these four elements while the customer generally provides fuel, traffic rights, schedules, and commercial distribution. |
| ACTK | Available Cargo Tonne-Kilometres: A capacity metric calculated by multiplying available cargo payload tonnes by the distance flown. It is used to compare cargo capacity with actual demand. |
| AD | Airworthiness Directive: A legally enforceable instruction issued by an aviation authority to correct an unsafe condition in an aircraft, engine, propeller, appliance, or component. |
| ALTA | Latin American and Caribbean Air Transport Association: A regional association representing airlines and aviation stakeholders across Latin America and the Caribbean. |
| AMM | Aircraft Maintenance Manual: The manufacturer-controlled manual containing procedures and technical instructions for inspecting, servicing, troubleshooting, and repairing an aircraft. |
| AMO | Approved Maintenance Organization: A maintenance provider authorized by an aviation authority to perform specified work on aircraft or components under an approved quality system. |
| AMP | Aircraft Maintenance Programme: The approved schedule of inspections, tasks, intervals, and life limits used to maintain continuing airworthiness. |
| AOC | Air Operator Certificate: Regulatory authorization confirming that an operator has the organization, personnel, aircraft, systems, and procedures required to conduct specified commercial air operations safely. |
| AOG | Aircraft on Ground: A condition in which an aircraft cannot operate because of a technical defect or missing part, often triggering urgent maintenance and logistics activity. |
| APEX | Airline Passenger Experience Association: An industry association focused on passenger experience, cabin interiors, inflight entertainment, connectivity, service, and related standards. |
| APIS | Advance Passenger Information System: A framework through which airlines transmit passenger and crew identity data to border-control authorities before arrival or departure. |
| APU | Auxiliary Power Unit: A small onboard turbine that provides electrical power and pneumatic air, particularly while the main engines are not running. |
| ARC | Airlines Reporting Corporation: A U.S.-based settlement and data organization that supports transactions between airlines and accredited travel agencies. |
| ASAP | Aviation Safety Action Program: A voluntary U.S. reporting program through which airline employees can disclose safety events for corrective action under defined nonpunitive conditions. |
| ASK | Available Seat Kilometres: A passenger-capacity metric calculated by multiplying available seats by kilometres flown. |
| ASM | Available Seat Miles: The mile-based equivalent of available seat kilometres, widely used by North American carriers to measure passenger capacity. |
| ASRS | Aviation Safety Reporting System: A confidential U.S. safety-reporting system administered by NASA that collects and analyzes voluntarily reported aviation incidents. |
| ATA | Air Transport Association of America: The former name of Airlines for America and the source of the ATA chapter numbering system still used to organize aircraft maintenance documentation by system. |
| ATK | Available Tonne-Kilometres: A total-capacity metric combining available passenger, baggage, mail, and cargo payload tonnes with distance flown. |
| ATPCO | Airline Tariff Publishing Company: An industry organization that distributes airline fares, rules, schedules, and related pricing data to reservation and retailing systems. |
| ATPL | Airline Transport Pilot Licence: The highest standard category of civil pilot licence and generally the qualification required to act as pilot in command of a commercial air transport aircraft. |
| AWB | Air Waybill: The principal contract-of-carriage document for an air cargo shipment, containing routing, shipper, consignee, commodity, weight, and charge information. |
| B | |
| BCF | Boeing Converted Freighter: A Boeing passenger aircraft converted under an approved program for dedicated cargo service. |
| BELF | Break-Even Load Factor: The load factor at which traffic revenue equals operating cost, making it a useful indicator of profitability sensitivity to capacity and yield. |
| BSA | Block Space Agreement: A commercial arrangement under which a customer purchases a defined amount of cargo capacity on specified flights for an agreed period or schedule. |
| BSP | Billing and Settlement Plan: An IATA system that consolidates reporting and settlement between participating airlines and accredited passenger sales agents. |
| C | |
| CAA | Civil Aviation Authority: The national body responsible for civil aviation regulation, certification, oversight, and enforcement in many jurisdictions. |
| CAAC | Civil Aviation Administration of China: China’s national civil aviation regulator, responsible for airline certification, safety oversight, market regulation, and operating approvals. |
| CAME | Continuing Airworthiness Management Exposition: A controlled document describing how an organization manages continuing airworthiness, responsibilities, procedures, records, and regulatory compliance. |
| CAMO | Continuing Airworthiness Management Organisation: An approved organization responsible for ensuring that aircraft remain airworthy through maintenance planning, records control, defect management, and regulatory compliance. |
| CASK | Cost per Available Seat Kilometre: A unit-cost metric calculated by dividing operating cost by available seat kilometres. |
| CASM | Cost per Available Seat Mile: The mile-based unit-cost measure widely used to compare operating efficiency among airlines. |
| CASS | Cargo Accounts Settlement Systems: IATA settlement systems that streamline billing and payment between airlines and cargo agents or freight forwarders. |
| CAST | Commercial Aviation Safety Team: A U.S. government-industry partnership that analyzes aviation risk and develops voluntary safety enhancements for commercial operations. |
| CCA | Cargo Charges Correction Advice: A standardized document used to communicate and authorize corrections to charges or other financial details on an air waybill. |
| CCQ | Cross-Crew Qualification: A training concept that enables qualified pilots to transition efficiently between related aircraft types with common cockpit design and operating philosophy. |
| CDL | Configuration Deviation List: An approved list identifying external aircraft parts that may be missing for dispatch, together with operating limitations and performance penalties. |
| CEIV | Center of Excellence for Independent Validators: An IATA certification framework used to assess specialized cargo handling capabilities, including pharmaceuticals, live animals, perishables, and lithium batteries. |
| CFIT | Controlled Flight Into Terrain: An accident category in which an airworthy aircraft under crew control unintentionally strikes terrain, water, or an obstacle. |
| CI | Cost Index: A flight-management input expressing the trade-off between time-related operating cost and fuel cost to determine an economically optimized speed profile. |
| CLF | Cargo Load Factor: The proportion of available cargo tonne-kilometres used by revenue cargo traffic, indicating capacity utilization. |
| CMM | Component Maintenance Manual: A manufacturer-issued manual containing maintenance, testing, repair, assembly, and overhaul instructions for a specific aircraft component. |
| CORSIA | Carbon Offsetting and Reduction Scheme for International Aviation: ICAO’s global framework for monitoring international aviation emissions and addressing qualifying growth through eligible fuels and emissions units. |
| CPA | Capacity Purchase Agreement: A contract under which one airline purchases flight capacity operated by another carrier, commonly in regional passenger and outsourced cargo networks. |
| CRM | Crew Resource Management: Training and operating practices designed to improve communication, decision-making, situational awareness, leadership, and teamwork among crew members. |
| CSD | Consignment Security Declaration: A cargo-security record documenting the security status of a consignment, controls applied, and regulated parties responsible for handling it. |
| CTK | Cargo Tonne-Kilometres: A traffic metric calculated by multiplying cargo tonnes carried by distance flown. |
| D | |
| DCS | Departure Control System: The operational system used for passenger check-in, seat assignment, boarding control, baggage acceptance, and flight closeout. |
| DG | Dangerous Goods: Articles or substances capable of posing a hazard to health, safety, property, or the environment during air transport and therefore subject to strict classification and handling rules. |
| DGD | Dangerous Goods Declaration: A shipper-prepared document certifying that regulated goods have been properly classified, packed, marked, labeled, and documented for air transport. |
| DGR | Dangerous Goods Regulations: IATA’s operational rules for preparing, accepting, handling, and transporting hazardous articles and substances by air. |
| DMC | Direct Maintenance Cost: The labor, material, repair, and related expense directly attributable to maintaining an aircraft or fleet. |
| DOC | Direct Operating Cost: Costs directly associated with flight operations, typically including fuel, crew, maintenance, navigation, airport, and aircraft ownership expenses. |
| DOT | United States Department of Transportation: The federal department responsible for airline consumer protection, economic authority, competition policy, and broader transportation regulation in the United States. |
| E | |
| EAS | Essential Air Service: A U.S. program subsidizing scheduled air service to eligible communities that might otherwise lose commercial connectivity. |
| EASA | European Union Aviation Safety Agency: The EU agency responsible for common civil aviation safety and environmental rules, certification, and oversight coordination. |
| e-AWB | Electronic Air Waybill: The electronic form of the air cargo contract of carriage, enabling paperless shipment processing between carriers and freight forwarders. |
| EBITDAR | Earnings Before Interest, Taxes, Depreciation, Amortization and Rent: A financial measure often used to compare airlines with different aircraft ownership and leasing structures by excluding rental expense as well as major nonoperating and noncash items. |
| ECAC | European Civil Aviation Conference: An intergovernmental organization that develops harmonized European approaches to aviation security, facilitation, safety, and environmental policy. |
| e-CSD | Electronic Consignment Security Declaration: The digital version of the air cargo security declaration, allowing security-status information to accompany a shipment electronically. |
| EDTO | Extended Diversion Time Operations: Operations conducted on routes where an aircraft may be beyond a prescribed diversion time from an adequate aerodrome, requiring specific aircraft, maintenance, dispatch, and operational approvals. |
| EETC | Enhanced Equipment Trust Certificate: A secured financing structure used by airlines to fund aircraft purchases through debt backed by aircraft collateral and bankruptcy-protection mechanisms. |
| EFB | Electronic Flight Bag: An approved electronic device or application platform that provides pilots with charts, manuals, calculations, flight documents, and operational information. |
| EGPWS | Enhanced Ground Proximity Warning System: An aircraft safety system that combines terrain data, position information, and predictive logic to warn crews of potential terrain conflicts. |
| ELT | Emergency Locator Transmitter: An aircraft distress beacon designed to transmit identifying and location information following an accident or emergency activation. |
| EMD | Electronic Miscellaneous Document: An industry-standard electronic record used to issue and account for ancillary services such as baggage, seat selection, lounge access, and change fees. |
| ERA | European Regions Airline Association: A trade association representing regional airlines and associated aviation businesses in Europe. |
| ETOPS | Extended-range Twin-engine Operational Performance Standards: The established term for approvals and controls that permit qualifying twin-engine aircraft to operate routes with extended diversion times. |
| EU ETS | European Union Emissions Trading System: The EU cap-and-trade program under which covered aviation operators must monitor emissions and surrender allowances for qualifying flights. |
| F | |
| FAA | Federal Aviation Administration: The U.S. agency responsible for civil aviation safety regulation, certification, airworthiness, operating standards, and oversight. |
| FAR | Federal Aviation Regulations: The commonly used name for U.S. civil aviation rules codified in Title 14 of the Code of Federal Regulations. |
| FDM | Flight Data Monitoring: The systematic collection and analysis of recorded flight data to identify operational risk, unstable trends, procedural deviations, and opportunities for safety improvement. |
| FDP | Flight Duty Period: A regulated duty interval encompassing flight-related work from reporting until completion, used in crew scheduling and fatigue management. |
| FFM | Cargo Flight Manifest Message: A standardized electronic cargo message listing shipments loaded or planned for carriage on a flight. |
| FMS | Flight Management System: An onboard computer system that integrates navigation, aircraft performance, route guidance, and fuel-efficient flight-profile calculations. |
| FOQA | Flight Operational Quality Assurance: The U.S. term for a voluntary program that analyzes routinely recorded flight data to identify and mitigate operational risk. |
| FRMS | Fatigue Risk Management System: A data-driven framework for managing crew fatigue through scientific principles, operational evidence, reporting, and continuous monitoring. |
| FSC | Full-Service Carrier: An airline business model generally characterized by network connectivity, multiple cabin products, bundled services, and significant connecting traffic. |
| FSC | Fuel Surcharge: A separately identified charge intended to recover part of an airline’s fuel expense, used in passenger ticketing and air cargo pricing. |
| FTK | Freight Tonne-Kilometres: A measure of freight traffic calculated by multiplying tonnes transported by distance flown. |
| FTL | Flight Time Limitations: Regulatory limits and associated requirements governing crew flight time, duty periods, rest, and cumulative workload. |
| G | |
| GPWS | Ground Proximity Warning System: An onboard system that warns pilots when the aircraft is in potentially unsafe proximity to terrain or descending in a hazardous configuration. |
| GSA | General Sales Agent: A third party appointed to represent an airline’s passenger or cargo sales activities in a defined market. |
| GSSA | General Sales and Service Agent: A representative that provides cargo sales and broader local support, potentially including reservations, capacity management, documentation, and customer service. |
| H | |
| HFACS | Human Factors Analysis and Classification System: A structured method for examining how organizational conditions, supervision, preconditions, and individual actions contribute to safety events. |
| HEFA | Hydroprocessed Esters and Fatty Acids: A commercially established pathway for producing sustainable aviation fuel from waste oils, fats, and other lipid feedstocks. |
| I | |
| IATA | International Air Transport Association: The global airline trade association that develops commercial and operational standards, accreditation systems, settlement programs, manuals, and industry policy positions. |
| ICAO | International Civil Aviation Organization: The United Nations specialized agency that establishes global standards and recommended practices for international civil aviation. |
| ICH | IATA Clearing House: A multilateral settlement mechanism that enables participating airlines and aviation companies to offset and settle intercompany receivables and payables. |
| ICS2 | Import Control System 2: The EU customs advance-cargo-information system requiring carriers and other parties to submit shipment data for security risk analysis before arrival. |
| IEnvA | IATA Environmental Assessment: An aviation-specific environmental management and certification program covering areas such as flight operations, corporate activities, maintenance, and cabin operations. |
| IFALPA | International Federation of Air Line Pilots’ Associations: A global federation representing national pilot associations in safety, technical, professional, and regulatory matters. |
| IFE | In-Flight Entertainment: Cabin systems and content that provide passengers with video, audio, games, information, and related onboard services. |
| IFEC | In-Flight Entertainment and Connectivity: The combined onboard technology environment for passenger media, internet access, messaging, and connected digital services. |
| IOC | Integrated Operations Control: The coordinated airline function that manages the live network across dispatch, crew, aircraft, maintenance, passenger, and disruption-recovery decisions. |
| IOSA | IATA Operational Safety Audit: An internationally recognized audit program assessing airline operational management and control systems against standardized safety requirements. |
| IROPS | Irregular Operations: Disruptions such as cancellations, significant delays, diversions, aircraft substitutions, and missed connections that require coordinated operational and customer recovery. |
| ISSA | IATA Standard Safety Assessment: A safety-assessment program designed for operators of smaller aircraft that are not eligible for the full operational safety audit program. |
| K | |
| KC3 | Third-Country Known Consignor: An EU aviation-security validated consignor located outside the EU whose cargo may enter the secure supply chain under specified controls. |
| L | |
| LAR | Live Animals Regulations: IATA requirements governing the acceptance, documentation, containers, handling, welfare, and air transport of live animals. |
| LCC | Low-Cost Carrier: An airline model built around simplified products, high asset utilization, lower unit costs, and extensive use of optional ancillary services. |
| LLP | Life-Limited Part: A safety-critical aircraft or engine part that must be removed from service when it reaches an approved time, cycle, or usage limit. |
| LMC | Last-Minute Change: A late alteration to passengers, baggage, cargo, fuel, or loading data that must be reflected in final weight-and-balance documentation. |
| LOC-I | Loss of Control In-Flight: An accident category involving an unintended departure from controlled flight that the crew cannot immediately correct. |
| LOPA | Layout of Passenger Accommodations: The approved cabin-layout drawing showing seats, exits, monuments, lavatories, galleys, and other passenger-compartment features. |
| LOSA | Line Operations Safety Audit: A confidential observational program used during normal flights to identify threats, crew errors, and effective risk-management behaviors. |
| LRU | Line-Replaceable Unit: An aircraft component designed to be removed and replaced at line-maintenance level to restore service quickly. |
| LTAG | Long-Term Aspirational Goal: ICAO’s collective goal of net-zero carbon emissions from international aviation by 2050, used to guide industry and government decarbonization planning. |
| LVO | Low Visibility Operations: Specially approved takeoff, approach, landing, and ground procedures used when visibility or cloud-base conditions fall below normal operating thresholds. |
| M | |
| MCT | Minimum Connection Time: The shortest published interval considered sufficient for a passenger and baggage to transfer between specified flights at an airport. |
| MEDA | Maintenance Error Decision Aid: A structured investigation process used to identify organizational and workplace factors contributing to maintenance errors. |
| MEL | Minimum Equipment List: An operator-specific approved document identifying equipment that may be temporarily inoperative while permitting dispatch under defined conditions and time limits. |
| MITA | Multilateral Interline Traffic Agreement: An IATA agreement establishing a common contractual framework for accepting passengers, baggage, or cargo across participating airlines. |
| MLW | Maximum Landing Weight: The highest certified aircraft weight permitted at landing under applicable structural and operational limits. |
| MMEL | Master Minimum Equipment List: The authority-approved baseline developed for an aircraft type from which an operator creates its own minimum equipment list. |
| MOC | Maintenance Operations Control: The airline function that coordinates real-time technical troubleshooting, defect rectification, maintenance planning, parts, and return-to-service decisions. |
| MOE | Maintenance Organisation Exposition: The controlled document describing an approved maintenance organization’s structure, capabilities, procedures, and compliance system. |
| MPA | Multilateral Proration Agreement: An agreement establishing methods for dividing interline passenger revenue among participating carriers. |
| MPD | Maintenance Planning Document: A manufacturer-issued planning source containing scheduled maintenance tasks and intervals used to develop an operator’s maintenance program. |
| MPL | Multi-Crew Pilot Licence: A competency-based pilot licence designed specifically for copilots operating multi-crew commercial aircraft. |
| MRB | Maintenance Review Board: A regulatory and industry body that reviews and approves the initial scheduled maintenance requirements for a new aircraft type. |
| MRBR | Maintenance Review Board Report: The approved report defining the initial minimum scheduled maintenance requirements for an aircraft, engine, or system. |
| MRO | Maintenance, Repair and Overhaul: The activities and provider market supporting aircraft airworthiness, component repair, engine overhaul, modifications, and heavy maintenance. |
| MSG-3 | Maintenance Steering Group–3: The industry methodology used to develop scheduled aircraft maintenance tasks through structured analysis of systems, structures, and zonal requirements. |
| MTOW | Maximum Takeoff Weight: The highest certified aircraft weight permitted at the start of the takeoff roll, subject to lower operational limits for specific conditions. |
| N | |
| NAA | National Aviation Authority: A country’s competent authority for civil aviation regulation, operator certification, airworthiness, licensing, and safety oversight. |
| NDC | New Distribution Capability: An IATA data-exchange standard enabling airlines to create and distribute richer offers, ancillary products, and personalized content through travel sellers. |
| NDT | Non-Destructive Testing: Inspection methods used to detect cracks, corrosion, delamination, or other defects without damaging the aircraft structure or component. |
| NEF | Nonessential Equipment and Furnishings: A controlled program for managing inoperative, damaged, or missing items that do not affect safe flight but still require documentation and rectification. |
| NOTOC | Notification to Captain: A document informing the aircraft commander about dangerous goods and other special loads carried onboard, including their location and emergency-relevant details. |
| O | |
| OCC | Operations Control Center: The central facility that monitors and manages daily flight execution, disruptions, aircraft routing, crew, dispatch, and operational recovery. |
| O&D | Origin and Destination: The true starting point and final endpoint of a passenger or shipment itinerary, regardless of intermediate connections. |
| OEM | Original Equipment Manufacturer: The company that designs and produces an aircraft, engine, system, or component and supplies the associated technical data and support. |
| OEW | Operating Empty Weight: The aircraft’s basic operating weight including crew, required equipment, fluids, and supplies but excluding usable fuel and traffic load. |
| OFP | Operational Flight Plan: The detailed plan used by dispatchers and flight crews to conduct a flight, including routing, weather, fuel, performance, alternates, and operational constraints. |
| OTP | On-Time Performance: A measure of the proportion of flights arriving or departing within a defined threshold of scheduled time. |
| P | |
| P2F | Passenger-to-Freighter: The conversion of a passenger aircraft for dedicated cargo operations through structural, systems, and interior modifications. |
| PAX | Passengers: Standard aviation shorthand used in schedules, operational messages, load documentation, and commercial reporting. |
| PBH | Power-by-the-Hour: A maintenance-support arrangement in which payments are linked to aircraft, engine, or component usage rather than individual repair events. |
| PCR | Perishable Cargo Regulations: IATA requirements and guidance for preparing, packaging, accepting, and handling temperature-sensitive and time-sensitive perishables. |
| PDP | Pre-Delivery Payment: A staged payment made to an aircraft manufacturer before delivery, representing a significant component of new-aircraft financing and liquidity planning. |
| PED | Portable Electronic Device: Passenger or crew equipment such as a phone, tablet, or laptop that is subject to operational, electromagnetic-interference, and lithium-battery controls. |
| PIC | Pilot in Command: The pilot designated as having final authority and responsibility for the operation and safety of a flight. |
| PLACI | Pre-Loading Advance Cargo Information: Shipment data submitted to authorities before loading so security risks can be assessed and any hold or additional-information request issued. |
| PLF | Passenger Load Factor: The proportion of available seat capacity used by revenue passenger traffic, commonly calculated as revenue passenger kilometres divided by available seat kilometres. |
| PNR | Passenger Name Record: The booking record containing itinerary, traveler, ticketing, contact, and service information associated with a passenger reservation. |
| PRASK | Passenger Revenue per Available Seat Kilometre: A unit-revenue metric that relates passenger revenue to offered seat capacity and distance. |
| PRM | Persons with Reduced Mobility: Passengers whose mobility is limited and who may require regulated accessibility support or assistance during travel. |
| PSO | Public Service Obligation: A government mechanism used to preserve air service on routes considered socially or economically essential but not commercially sustainable without support. |
| PSS | Passenger Service System: The core airline technology platform supporting reservations, inventory, ticketing, departure control, and passenger records. |
| PtL | Power-to-Liquid: A production pathway that combines renewable electricity, hydrogen, and captured carbon to create synthetic liquid fuel suitable for aviation after approved processing. |
| Q | |
| QAR | Quick Access Recorder: An onboard recording device that captures flight data in a format designed for routine download and operational safety analysis. |
| R | |
| RA3 | Third-Country Regulated Agent: An EU aviation-security validated cargo agent located outside the EU that applies approved security controls before consignments enter the secure supply chain. |
| RASK | Revenue per Available Seat Kilometre: Total operating revenue divided by available seat kilometres, used to assess revenue generation relative to offered passenger capacity. |
| RASM | Revenue per Available Seat Mile: The mile-based unit-revenue measure widely used by North American airlines. |
| RBD | Reservation Booking Designator: The booking-class code used to control fare availability, inventory, ticketing conditions, and revenue-management segmentation within a cabin. |
| RFS | Road Feeder Service: Scheduled trucking operated under an air cargo network and often identified by a flight number to connect airports and cargo gateways. |
| RII | Required Inspection Item: A maintenance task or work stage that requires an independent or specially authorized inspection because an error could endanger safe operation. |
| RPK | Revenue Passenger Kilometres: A passenger-traffic metric calculated by multiplying revenue passengers carried by kilometres flown. |
| RPM | Revenue Passenger Miles: The mile-based equivalent of revenue passenger kilometres, commonly used in North American reporting. |
| RTK | Revenue Tonne-Kilometres: A total traffic measure calculated by multiplying revenue payload tonnes, including passengers, baggage, cargo, and mail, by distance flown. |
| S | |
| SAF | Sustainable Aviation Fuel: Aviation fuel made from eligible renewable or waste-derived feedstocks, or synthetic pathways, that can reduce lifecycle greenhouse-gas emissions relative to conventional jet fuel. |
| SARPs | Standards and Recommended Practices: Technical and operational provisions adopted by ICAO and contained in the annexes to the Chicago Convention for implementation by member states. |
| SB | Service Bulletin: A manufacturer-issued document recommending or specifying an inspection, modification, repair, or maintenance action for an aircraft or component. |
| SEP | Safety and Emergency Procedures: Crew training and procedures covering emergency equipment, evacuation, firefighting, decompression, ditching, first aid, and other abnormal situations. |
| SFC | Specific Fuel Consumption: An efficiency measure relating fuel consumption to the power or thrust produced by an engine. |
| SIS | Simplified Invoicing and Settlement: An IATA platform supporting standardized electronic invoicing and settlement among airlines and other aviation participants. |
| SLB | Sale-and-Leaseback: A financing transaction in which an airline sells an aircraft to a lessor and immediately leases it back, releasing capital while retaining operational use. |
| SMS | Safety Management System: A formal, organization-wide framework for managing safety risk through policy, assurance, risk controls, reporting, and promotion. |
| SOP | Standard Operating Procedure: An approved, repeatable method for performing an operational task consistently and safely. |
| SPA | Special Prorate Agreement: A bilateral or limited agreement specifying how airlines divide revenue for interline itineraries outside standard industry proration rules. |
| SRM | Structural Repair Manual: The manufacturer’s approved source for assessing structural damage and performing standard aircraft structural repairs. |
| SSIM | Standard Schedules Information Manual: The IATA standard governing the formats, codes, and procedures used to exchange airline schedule and slot-related information. |
| SSR | Special Service Request: A standardized booking message used to request or confirm passenger services such as meals, mobility assistance, or unaccompanied-minor handling. |
| STC | Supplemental Type Certificate: Regulatory approval for a major change to the type design of an aircraft, engine, or propeller. |
| T | |
| TACT | The Air Cargo Tariff: An IATA cargo information product containing rates, rules, restrictions, schedules, and compliance data used in international air freight. |
| TAWS | Terrain Awareness and Warning System: An onboard safety system that predicts potential terrain conflicts and provides visual and aural warnings to the flight crew. |
| TC | Type Certificate: Regulatory approval confirming that an aircraft, engine, or propeller design complies with applicable airworthiness standards. |
| TCAS | Traffic Alert and Collision Avoidance System: A specific implementation of airborne collision avoidance technology that issues traffic advisories and, when necessary, vertical resolution advisories. |
| TCO | Third-Country Operator: An airline based outside the EU that must obtain EASA safety authorization before conducting commercial air transport operations into, within, or out of relevant European territories. |
| TCR | Temperature Control Regulations: IATA requirements and guidance for handling healthcare products and other temperature-sensitive cargo throughout air transport. |
| TEM | Threat and Error Management: An operational safety framework for anticipating threats, trapping errors, and managing undesired aircraft states before they create harmful outcomes. |
| TI | Technical Instructions for the Safe Transport of Dangerous Goods by Air: ICAO’s detailed international provisions for classifying, packing, documenting, accepting, and transporting dangerous goods aboard aircraft. |
| TIACA | The International Air Cargo Association: A global association representing airlines, airports, forwarders, handlers, technology companies, and other participants in the air cargo supply chain. |
| TOW | Takeoff Weight: The aircraft’s actual gross weight at the start of the takeoff roll, used for performance, structural, and runway calculations. |
| TRE | Type Rating Examiner: A regulator-authorized examiner qualified to conduct proficiency checks and skill tests for a specific aircraft type. |
| TRI | Type Rating Instructor: A qualified instructor authorized to provide training for pilots seeking or maintaining a rating on a specific aircraft type. |
| TSA | Transportation Security Administration: The U.S. agency responsible for security requirements affecting passenger airlines, cargo operators, screening programs, and regulated aviation entities. |
| TSFC | Thrust-Specific Fuel Consumption: A jet-engine efficiency measure relating the rate of fuel consumption to the thrust produced. |
| TSN | Time Since New: The total operating time accumulated by an aircraft, engine, or component since manufacture. |
| TSO | Time Since Overhaul: The operating time accumulated by an engine or component since its most recent approved overhaul. |
| U | |
| ULCC | Ultra-Low-Cost Carrier: An airline model emphasizing very low base fares, dense seating, high utilization, simplified operations, and extensive unbundling of optional services. |
| ULD | Unit Load Device: An aircraft-compatible container or pallet used to consolidate baggage, mail, or cargo for loading, restraint, and transport. |
| UMNR | Unaccompanied Minor: The standardized service designation for a child traveling without an accompanying eligible adult and requiring defined supervision and handover procedures. |
| W | |
| W&B | Weight and Balance: The process of calculating aircraft mass and center of gravity to ensure loading remains within structural, stability, and performance limits. |
| WSG | Worldwide Airport Slot Guidelines: IATA’s global framework for allocating and managing scarce airport slots, including coordination processes, historic precedence, and airline usage requirements. |
| Z | |
| ZFW | Zero Fuel Weight: The total aircraft weight excluding usable fuel, used to verify structural loading and calculate operational performance. |