SiamFlights Glossary

IATA

International Air Transport Association — 3-letter airport and 2-letter airline codes used across the industry. (source)

ICAO

International Civil Aviation Organization — 4-letter airport codes used in flight planning and the UN aviation agency. (source)

IRROPS

Irregular Operations — industry term for flight cancellations, delays and reroutes triggered by weather, mechanical or crew issues.

EU261

European Regulation (EC) No 261/2004 — establishes air passenger compensation rights up to €600 for delays, cancellations and denied boarding affecting EU departures and EU carriers. (source)

UK261

Post-Brexit UK retained version of EU261 — applies to flights departing UK airports, on UK carriers, or arriving at UK airports on EU carriers. (source)

GACA

General Authority of Civil Aviation, Saudi Arabia — regulates Saudi-registered airlines and Hajj/Umrah charter flights. (source)

APPR

Air Passenger Protection Regulations — Canadian flight-compensation framework administered by the Canadian Transportation Agency. (source)

CTA

Canadian Transportation Agency — the regulator that enforces APPR. (source)

DOT

United States Department of Transportation — Aviation Consumer Protection division enforces 14 CFR Part 250 refund and oversales rules. (source)

ANAC

Agência Nacional de Aviação Civil — Brazilian aviation regulator, enforces Resolução 400/2016 passenger-rights. (source)

DGCA

Directorate General of Civil Aviation, India — enforces Civil Aviation Requirements (CAR) Section 3 Series M passenger charter. (source)

ETIAS

European Travel Information and Authorisation System — visa-waiver electronic authorisation (€20, valid 3 years) required for most non-EU visa-exempt nationals from mid-2026. (source)

Schengen

26-country area of free movement within Europe; non-EU visitors travel under 90/180 short-stay rules unless they hold a long-stay visa. (source)

PNR

Passenger Name Record — the booking reference and itinerary record stored in airline reservation systems; used by border control and police for advance passenger info.

MTOW

Maximum Take-Off Weight — used by airports to charge landing fees and by regulators for noise classifications.

MCT

Minimum Connecting Time — the shortest legally guaranteed transfer window between two flights at a given airport; if your itinerary is below MCT the airline owes you a rebook on misconnect.

RBD

Reservation Booking Designator — the fare-class letter (Y, M, K, etc.) that determines miles earned, change fees, and seat priority on award redemption.

AKL bag

Slang for a checked bag exceeding 23 kg domestic limit but allowed under 32 kg international rules; named after Auckland-route abuse.

FF program

Frequent Flyer / loyalty programme — airline points earned per flight or partner spend, redeemable for award flights or upgrades.

Codeshare

An airline operating its own flight number on a partner's metal — the marketed carrier is the seller, the operating carrier is the airline that actually flies it. Compensation is generally owed by the OPERATING carrier.

Avianca Convention 1929 / Montreal 1999

Two international treaties governing airline liability for death, injury, baggage delay, and lost baggage. Montreal 1999 caps unverified baggage liability at 1,288 SDRs (~USD 1,700). (source)

SDR

Special Drawing Right — IMF accounting unit used in international aviation treaties to denominate compensation caps; 1 SDR ≈ USD 1.32 (varies). (source)

ATC delay

Air Traffic Control delay — a hold imposed by ATC for weather or congestion; in EU/UK261 frameworks this is generally considered "extraordinary circumstances" and the airline does NOT owe compensation (but does owe duty of care).

Force majeure

Civil-law concept of events beyond reasonable control (war, pandemic, volcanic eruption) — typically excluded from compensation claims but airlines still owe duty of care (rebooking, food, accommodation).

Duty of care

Airline obligation to provide meals, accommodation and re-routing to passengers stranded during disruption — applies under EU261, UK261, APPR and most modern frameworks, REGARDLESS of whether monetary compensation is also owed.

AggregateOffer

Schema.org type used to advertise fare ranges (low to high) on flight metasearch pages. (source)

CAAT

Civil Aviation Authority of Thailand — Thai aviation regulator. (source)

Songkran

Thai New Year (April 13-15); domestic and ASEAN regional flight surge.

Loy Krathong

Thai festival of lights (November full moon); domestic Chiang Mai / Bangkok flight surge.

Buddhist Lent

Khao Phansa (July) to Ok Phansa (October); minor flight pattern shifts for merit-making travel.

Hajj Quota Thailand

Allocation determined annually by Saudi Ministry of Hajj for Thai Muslim pilgrims; managed via Sheikh-ul-Islam Office.

Tax-Free

Thailand VAT refund scheme for international tourists; refund counter at Suvarnabhumi (BKK) and Don Mueang (DMK).

AOT

Airports of Thailand Public Co Ltd — operator of Suvarnabhumi, Don Mueang, Phuket, Chiang Mai and 3 other Thai airports. (source)

Last reviewed: 2026-06-03 · Related: taxonomy, methodology.