Aviation Security Glossary: 35 Essential Terms Explained
A plain-English glossary of aviation security and airspace risk terminology — AVSEC, NOTAM, overflight risk, FIR, MANPADS, insider threat and more — defined for analysts, dispatchers and operations teams.
Aviation security covers a dense, acronym-heavy vocabulary that spans regulation, threat intelligence, airspace management and ground operations. This glossary defines the terms most often used in airline operations centres, dispatch desks and security teams — in plain English, with links to deeper explainers where they exist.
Use it as a quick reference, or read it top to bottom to build a working mental model of how the field fits together.
Regulatory and governance terms
AVSEC (Aviation Security)
The discipline of protecting civil aviation against acts of unlawful interference — hijacking, sabotage, bombings, cyber attacks and insider threats. It is distinct from safety, which deals with accidental harm. See the full explainer: What is AVSEC?.
ICAO
The International Civil Aviation Organization, the United Nations body that sets global aviation standards through documents called Annexes.
ICAO Annex 17
The international standard dedicated to aviation security. It defines the baseline measures every contracting state must implement to safeguard civil aviation against unlawful interference.
SARPs
Standards and Recommended Practices — the binding standards and advisory recommendations ICAO publishes in its Annexes.
NCASP
National Civil Aviation Security Programme — the document in which each state codifies how it meets ICAO Annex 17 obligations.
SMS
Safety Management System — a structured, organisation-wide approach to managing safety risk, mandated under ICAO Annex 19.
Airspace and overflight terms
FIR (Flight Information Region)
A defined volume of airspace within which flight information and alerting services are provided. FIRs are the basic building block of how the world divides controlled airspace.
UIR (Upper Information Region)
The upper-altitude counterpart to a FIR, covering high-level airspace used by cruising jets.
Overflight risk
The risk an aircraft is exposed to while transiting the airspace of a country, rather than landing there — for example exposure to surface-to-air weapons during a conflict. See What is conflict zone airspace risk?.
Conflict zone
Airspace over or near an area of armed conflict where civil aircraft may face deliberate or accidental targeting. ICAO maintains a Conflict Zone Information Repository to share state advisories.
CZIB
Conflict Zone Information Bulletin — a notice (notably issued by EASA in Europe) warning operators about risks in specific airspace.
NOTAM
Notice to Air Missions (formerly Notice to Airmen) — a time-critical advisory about the status of airspace, navigation aids, airports or hazards. Security-relevant NOTAMs may close airspace or warn of conflict.
GPS jamming
Deliberate interference that denies satellite navigation signals over an area, degrading aircraft positioning. Increasingly common near conflict zones.
GPS spoofing
Transmission of false satellite signals that mislead an aircraft into computing an incorrect position — more dangerous than jamming because the error is not obvious to the crew.
Threat terms
Unlawful interference
The umbrella legal term for acts against civil aviation: hijacking, hostage-taking, sabotage, attacks on facilities and the use of aircraft as weapons.
Insider threat
A risk posed by people with legitimate, trusted access — staff, contractors or crew — who exploit that access for malicious ends.
MANPADS
Man-Portable Air-Defence Systems — shoulder-launched surface-to-air missiles. Their proliferation in conflict zones is a primary driver of overflight risk to aircraft at lower altitudes.
Landside
The publicly accessible areas of an airport (terminals, kerbside, car parks) before security screening — a soft target for attacks.
Airside
The secure, access-controlled areas beyond screening: aprons, taxiways and runways.
Standoff attack
An attack launched from outside the airport perimeter, such as mortar or rocket fire onto the apron.
Operations and risk terms
FRAT
Flight Risk Assessment Tool — a structured method for scoring the cumulative risk of a specific flight before departure. See What is a flight risk assessment tool?.
Threat intelligence
Processed, analysed information about threats that supports a decision. In aviation it underpins route, destination and crew decisions — see What is aviation security intelligence?.
OSINT
Open-Source Intelligence — intelligence derived from publicly available sources such as news, social media, official advisories and flight data.
Duty of care
An operator's legal and moral obligation to take reasonable steps to protect the safety and security of its crew and passengers, including during layovers. See What is crew layover security?.
Layover
A rest period crew spend away from base between flights, typically at a hotel in the destination city — a window in which they are exposed to local security conditions.
OCC
Operations Control Centre — the nerve centre where an airline monitors and manages its live flight operations.
Dispatch
The function responsible for planning a flight, including route, fuel and the operational risk picture, jointly with the captain.
Risk appetite
The level of risk an organisation is willing to accept in pursuit of its objectives — the benchmark against which a FRAT score is judged.
Frequently asked questions
What is the difference between aviation safety and aviation security?
Safety addresses accidental harm — weather, mechanical failure, human error. Security addresses deliberate, malicious acts against aviation. Different teams, regulations and tools, though they increasingly share data.
Is a NOTAM a security tool?
Not exclusively. NOTAMs cover all operationally significant changes, but security-relevant NOTAMs — airspace closures, conflict warnings, GPS interference notices — are a key input to security decisions.
Who decides whether to overfly a conflict zone?
The operator, informed by state advisories, ICAO repository entries and its own risk assessment. States can close their own airspace but cannot compel others to avoid it, which is why operator judgement matters.
Want the bigger picture? Start with What is aviation security intelligence? and follow the links from there.
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