Aviation compliance glossary
Plain-language definitions of the regulations, documents, and programs that shape aviation compliance — from FAA Part 135 to SMS, CAPA, and continuing airworthiness.
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14 CFR Part 119(Part 119)
The FAA regulations governing certification of air carriers and commercial operators — the part under which the operating certificate itself and its operations specifications are issued.
14 CFR Part 121(Part 121)
The FAA regulations for scheduled air carrier (airline) operations. Part 121 carriers face the most extensive operational, training, and maintenance requirements.
14 CFR Part 135(Part 135)
The section of the U.S. Federal Aviation Regulations governing commuter and on-demand operations, including most charter and air-taxi flying. It sets requirements for crew qualifications, flight operations, aircraft and equipment, training, and recordkeeping.
14 CFR Part 145(Part 145)
FAA regulations for certificated repair stations (maintenance, repair, and overhaul organizations), covering housing, equipment, personnel, and quality systems.
14 CFR Part 5(Part 5)
The FAA's Safety Management System regulations, setting the requirements for safety policy, safety risk management, safety assurance, and safety promotion. The FAA's SMS rulemaking extends Part 5 requirements to Part 135 operators.
14 CFR Part 91(Part 91)
The FAA's general operating and flight rules that apply to nearly all civil aircraft operations, including private and business flying not conducted for compensation or hire under Part 135 or 121.
A
Air Charter Safety Foundation(ACSF)
An industry foundation whose Industry Audit Standard provides third-party auditing of on-demand operators, used by many charter buyers as a vetting benchmark.
Air Operator Certificate(AOC)
The authorization (called an Air Carrier or Operating Certificate under FAA rules) that permits an operator to conduct commercial air transport, issued after the regulator verifies the operator can comply with the applicable rules.
Airworthiness Directive(AD)
A legally enforceable FAA rule under 14 CFR Part 39 requiring inspection, repair, or modification to correct an unsafe condition in an aircraft, engine, propeller, or appliance. Compliance must be recorded per aircraft, including the method and date.
Approved Aircraft Inspection Program(AAIP)
An FAA-approved inspection program a Part 135 operator of nine-or-fewer-seat aircraft may use in place of manufacturer or 100-hour inspection schedules.
ARGUS Rating
A third-party due-diligence rating for charter operators issued by ARGUS International, based on historical safety analysis and, at higher tiers, on-site audit.
ASAP(ASAP)
Aviation Safety Action Program — a voluntary self-reporting programme run under a memorandum of understanding between the operator, the FAA and often the employee group. Reports accepted into ASAP generally carry enforcement protection, so it surfaces events a punitive system would never hear about. Where FOQA shows what the data says, ASAP shows what the crew saw.
Aviation Safety Action Program(ASAP)
A voluntary FAA program under which employees report safety events with protections against punitive use, feeding the operator's safety management processes.
C
Canadian Aviation Regulations(CARs)
The regulations administered by Transport Canada governing civil aviation in Canada, including commercial air services and flight operations equivalent in purpose to the FAA's operating parts.
Check Pilot
A pilot authorized by the FAA (or the operator under its approved program) to conduct the tests and checks required by Part 135, such as §135.293 competency checks and §135.299 line checks.
Competency Check
The pilot check required by 14 CFR §135.293, covering knowledge and maneuvers appropriate to the aircraft class or type, required within the preceding 12 calendar months of serving as a pilot.
Continuing Airworthiness
The set of processes ensuring that an aircraft complies with applicable airworthiness requirements and remains in a condition for safe operation throughout its life, including maintenance, records, and reliability programs.
Continuous Airworthiness Maintenance Program(CAMP)
The structured maintenance program required for Part 135 operators of aircraft with ten or more passenger seats, encompassing inspections, scheduled maintenance, and reliability oversight.
Controlled Flight Into Terrain(CFIT)
An accident category in which an airworthy aircraft under crew control is flown into terrain, water, or obstacles — a principal target of TAWS requirements and CFIT-avoidance training.
Corrective and Preventive Action(CAPA)
The disciplined process of correcting an identified nonconformity and preventing its recurrence, typically with an assigned owner, a corrective-action plan, a target date, and verification of closure.
D
Dirty Dozen
Twelve human-factors conditions that recur in maintenance and operational error — lack of communication, complacency, lack of knowledge, distraction, lack of teamwork, fatigue, lack of resources, pressure, lack of assertiveness, stress, lack of awareness, and norms. Originating in maintenance human-factors training, they are now used as a checklist for investigating why a procedure was not followed.
Duty Period
The elapsed time from when a crewmember reports for an assignment until released from it. Part 135 flight-time limitations and rest requirements (e.g., §135.267 for unscheduled one- and two-pilot crews) constrain how duty and flight time may be scheduled.
E
EASA
The European Union Aviation Safety Agency, the body responsible for civil aviation safety rulemaking and oversight across EASA member states, including air operations (Part-ORO) and continuing airworthiness (Part-CAMO).
Electronic Flight Bag(EFB)
A device or application hosting the documents and performance tools crews use in flight — commonly the distribution point for current manuals and charts. Revision control obligations extend to EFB content.
Emergency Locator Transmitter(ELT)
A crash-activated radio beacon required on most aircraft, with battery and inspection requirements that appear in maintenance-records audits.
Emergency Response Plan(ERP)
The documented plan for transitioning from normal to emergency operations and back — who is notified, who speaks for the operator, how families and authorities are handled, and how it is exercised. Required content within a safety management system under 14 CFR Part 5 Subpart B.
F
Federal Aviation Regulations(FARs)
The common name for the aviation rules codified in Title 14 of the Code of Federal Regulations (14 CFR). 'FAR' and '14 CFR' references point to the same body of law.
Flight Following
The system by which an operator tracks the progress of its flights. For many Part 135 operators, an approved flight-locating or following procedure stands in place of a Part 121-style dispatch system.
Flight Operations Manual(FOM)
The manual containing the procedures, limitations, and guidance flight crews use to operate the fleet safely and in compliance with regulations and the operator's certificate.
Flight Risk Assessment Tool(FRAT)
A structured pre-flight scoring tool that quantifies mission risk factors (crew, weather, airport, aircraft) so elevated-risk flights receive additional review before release.
Flight Standards District Office(FSDO)
The FAA's local field office responsible for certification and surveillance of operators, airmen, and agencies in its district. A Part 135 certificate holder's day-to-day FAA relationship runs through its FSDO.
Flight Time
Time from when an aircraft first moves under its own power for flight until it comes to rest after landing ('block time'). The basis of Part 135 flight-time limitation tracking.
FOQA(FOQA)
Flight Operational Quality Assurance — the voluntary programme that analyses routinely recorded flight data to find trends before they become incidents. De-identified by design, and under 14 CFR Part 13.401 the data is protected from use in most FAA enforcement action, which is what makes crews willing to support it.
G
Gap Analysis
A structured comparison between what a manual or process actually says and what a regulation or standard requires, producing a list of gaps to remediate. In compliance work it is the basis for corrective action and audit preparation.
General Operations Manual(GOM)
The controlling manual describing how an operator conducts its business in compliance with its operating certificate — policies, responsibilities, and procedures that operational manuals expand on.
H
Hazard
A condition or object with the potential to cause harm. In SMS practice, hazards are identified, reported, and assessed for risk before controls are assigned.
I
ICAO Annex 19
The ICAO annex that consolidates safety management provisions, establishing the framework for State Safety Programmes and operator Safety Management Systems.
IMSAFE Checklist(IMSAFE)
An FAA self-assessment checklist a pilot runs before flight — Illness, Medication, Stress, Alcohol, Fatigue, Emotion — covering the “Pilot” element of the PAVE framework. It supports, and does not replace, the fitness-for-duty and duty-time limits an operator sets under its own rules.
Instrument Proficiency Check(IPC)
The instrument check required by 14 CFR §135.297 for PICs flying under IFR, demonstrating instrument competency, on the schedule the rule prescribes.
IOSA
The IATA Operational Safety Audit, an internationally recognized evaluation of the operational management and control systems of an airline.
IS-BAO
The International Standard for Business Aircraft Operations, a code of best practice designed to help business aviation operators achieve high levels of safety and professionalism.
IS-BAO(IS-BAO)
International Standard for Business Aircraft Operations — an IBAC code of best practice, built around an SMS, that operators register against at one of three progressive stages. Voluntary rather than regulatory, but widely treated by charter buyers as a quality signal.
ISAGO(ISAGO)
IATA Safety Audit for Ground Operations — an audit programme for ground handling providers at specific stations, distinct from IOSA, which audits airlines.
J
Just Culture
A safety culture that distinguishes honest error, which is treated as a system problem to learn from, from reckless or wilful violation, which is not. It is the precondition for a reporting system that works: people report what they did wrong only when they can predict what happens next.
L
Line Check
The en-route check required by 14 CFR §135.299, in which a check pilot observes a PIC conducting a flight segment representative of the operator's operations.
M
Master Minimum Equipment List(MMEL)
The FAA-developed list, per aircraft type, of equipment that may be inoperative under specified conditions. An operator's MEL is derived from — and can be no less restrictive than — the MMEL.
Minimum Equipment List(MEL)
An approved list specifying the instruments and equipment that may be inoperative for a flight, along with any conditions and limitations, derived from the aircraft's Master Minimum Equipment List.
N
Notice to Air Missions(NOTAM)
A notice containing time-critical aeronautical information — runway closures, navaid outages, airspace restrictions — that crews must review in preflight action.
O
Operational Control
The exercise of authority over initiating, conducting, and terminating a flight. Part 135 requires the certificate holder — not a broker or customer — to hold and exercise operational control, and inspectors probe for improper delegation.
Operations Specifications(OpSpecs)
The authorizations, limitations, and procedures that accompany an operating certificate, defining exactly what an operator is approved to do (aircraft, areas, kinds of operations, and special authorizations).
P
PAVE Checklist(PAVE)
An FAA preflight risk-assessment framework that sorts the hazards of a given flight into four categories — Pilot, Aircraft, enVironment, and External pressures. It is a pilot-facing companion to a formal Flight Risk Assessment Tool: PAVE structures the judgement, the FRAT records and scores it.
Pilot in Command(PIC)
The pilot responsible for the operation and safety of the flight. Part 135 sets specific PIC qualification, testing, and currency requirements (e.g., §135.243, §135.293).
Principal Avionics Inspector(PAI)
The FAA inspector assigned to oversee an operator's avionics and electrical systems maintenance and related programs.
Principal Maintenance Inspector(PMI)
The FAA inspector assigned to oversee an operator's maintenance program, records, and continuing airworthiness arrangements.
Principal Operations Inspector(POI)
The FAA inspector assigned to oversee an operator's flight operations — the person who reviews manuals, training programs, and OpSpecs, and who conducts or directs operational surveillance.
R
Recurrent Training
The periodic training required to keep crewmembers qualified, defined by the operator's approved training program under Part 135 Subpart H. Distinct from — and in addition to — the recurrent tests and checks of §135.293/.297/.299.
Rest Period
A continuous period free of all duty. Part 135 prescribes minimum rest based on the operation type and flight time, and records must be able to demonstrate compliance.
Risk Assessment
The evaluation of a hazard's consequences in terms of severity and likelihood, used to prioritize mitigation. A core activity of the safety risk management component of an SMS.
S
Safety Assurance
The SMS component comprising audits, evaluations, investigation, and performance monitoring — the processes that confirm risk controls are working and the system is functioning as designed.
Safety Management System(SMS)
A systematic approach to managing safety, including safety policy, safety risk management, safety assurance, and safety promotion. ICAO Annex 19 establishes SMS standards adopted by civil aviation authorities.
Safety Performance Indicator(SPI)
A measure used to monitor whether safety risk controls are working — for example the rate of unstable approaches or of overdue corrective actions. Paired with a target, an SPI is what turns safety assurance from an opinion into something an inspector can read.
Safety Policy
The first component of an SMS: the accountable executive's documented commitment to safety, with defined safety accountabilities, roles, and the procedures that set how safety is managed. Under 14 CFR Part 5 subpart B it is what the operator's safety objectives and accountabilities are written against.
Safety Promotion
The fourth SMS component: the training, communication, and culture work that lets people in the operation recognise hazards and report them without fear of reprisal. 14 CFR Part 5 subpart E covers competency, training, and safety communication.
Safety Risk Management(SRM)
The second SMS component: a repeatable process for describing the system, identifying hazards, analysing and assessing the resulting risk, and applying controls until the residual risk is acceptable. 14 CFR Part 5 subpart C requires it whenever a new hazard or a change to the operation is identified.
Second in Command(SIC)
A required or assigned copilot position. Part 135 defines when an SIC is required and the qualification and checking rules that apply.
Supplemental Type Certificate(STC)
FAA approval of a modification to a type-certificated product — the mechanism by which most aftermarket equipment installations are approved.
T
Terrain Awareness and Warning System(TAWS)
Equipment providing terrain alerts to reduce controlled-flight-into-terrain risk. Required for certain turbine-powered aircraft configurations under FAA rules.
Traffic Alert and Collision Avoidance System(TCAS)
Airborne equipment that tracks nearby transponder-equipped aircraft and issues traffic and resolution advisories to prevent midair collisions.
Type Certificate(TC)
The FAA approval of an aircraft, engine, or propeller design, establishing the configuration and limitations against which airworthiness is judged.
V
Voluntary Disclosure Reporting Program(VDRP)
The FAA program through which a certificate holder may voluntarily disclose an apparent violation and propose a comprehensive fix, potentially in lieu of civil penalty.
W
Wyvern Wingman
A third-party charter-operator certification from Wyvern based on an on-site audit against its published standard — like ARGUS ratings, frequently requested by charter buyers.
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