Aviation Glossary
Every acronym, code, and term you will encounter when booking, monitoring, and switching fares.
Alternative Dispute Resolution
An independent body that resolves complaints between passengers and airlines without going to court. Required before small claims in many jurisdictions.
Portuguese Civil Aviation Authority
The national enforcement body for air passenger rights in Portugal. Equivalent to the UK CAA.
Bilateral Interline E-Ticketing Agreement
An agreement between two carriers allowing electronic tickets to be issued on one carrier and flown on another.
UK Civil Aviation Authority
The UK's aviation regulator and national enforcement body for EU261-equivalent passenger rights post-Brexit.
Commercial Interline/Discount Zone
A fare zone used in staff travel where employees of partner airlines can purchase discounted tickets at commercial interline rates.
EU Regulation 261/2004
The primary regulation governing passenger compensation for flight cancellation, delay, denied boarding, and downgrade within the EU/EEA.
Frequent Flyer
A loyalty programme member. Miles or points earned through flying and partner spending can be redeemed for flights, upgrades, or services.
First Notice of Loss
The initial report filed with an insurer when a covered event occurs. In aviation, typically triggered by cancellation, delay, or baggage loss.
General Data Protection Regulation
EU regulation governing the processing and storage of personal data. Tailwind is GDPR-compliant and CNPD-registered.
Global Distribution System
A centralised reservation system (e.g. Amadeus, Sabre, Travelport) that aggregates airline inventory and distributes it to travel agents and booking platforms.
Industry Discount 50%
A 50% discount fare for airline employees. Often the highest-priority industry discount tier, sometimes confirmed.
Industry Discount 75%
A 75% discount fare for airline employees. Higher priority than ID90 but still typically standby.
Industry Discount 90%
A heavily discounted fare (90% off published rate) available to airline employees. Typically standby-only.
Industry Discount Fare System
The system that manages and distributes industry discount fares between participating carriers. Governs ID90/ID75/ID50 availability.
IATA Operational Safety Audit
The global standard for airline safety auditing. All 58 carriers in the Tailwind network are IOSA-certified.
Load Factor
The percentage of available seats filled on a flight. High load factors reduce standby clearing probability and may increase fare volatility.
Mutual Interline Billing Agreement
An agreement between carriers for mutual billing of interline traffic. Enables seamless ticketing across multiple airlines on a single itinerary.
New Distribution Capability
An IATA data standard that allows airlines to distribute rich content and fares directly to travel sellers, bypassing traditional GDS limitations.
On-Time Performance
The percentage of flights arriving within 15 minutes of scheduled time. A key metric for carrier reliability assessment.
Payment Card Industry Data Security Standard
The security standard for handling credit card data. Tailwind is PCI DSS Level 1 compliant. Payment data is never stored on our servers.
Passenger Name Record
The unique alphanumeric booking reference (e.g. XJZBG5) that identifies your reservation in the airline's system.
Special Drawing Rights
An international monetary unit defined by the IMF. Used in the Montreal Convention to express liability limits. 1 SDR is approximately 1.20 EUR.
Special Service Request
A coded message in the PNR requesting specific services: wheelchair assistance, meal preferences, bassinet, unaccompanied minor, etc.
Stopover Paid by Carrier
When a carrier's schedule requires an overnight connection, the airline provides hotel, meals, and transfers at no cost to the passenger.
Ticket Number
The 13-digit number on your e-ticket (e.g. 047-1234567890). Different from the PNR. Required for refund claims and interline transfers.
Write Once Read Many
A data storage method where records cannot be modified after creation. Tailwind uses WORM audit logs for all switch and payment events.
Cabin Classes
Standard IATA cabin designators. Y = Economy, W = Premium Economy, C = Business, F = First. Used in fare rules, PNR entries, and availability displays.
Revenue Interline/Discount Zone
A revenue-generating interline zone where discounted fares are offered to employees of partner airlines at rates higher than CIDZ but lower than public fares.
Zonal Employee Discount
A standardised staff travel fare structure based on distance zones rather than specific routes. Governed by bilateral agreements between carriers.
29 terms. Updated March 2026. Missing a term? Let us know.