Almost every rejected compensation claim in Europe uses these two words. The regulation does not define them, so their meaning comes from judgments of the Court of Justice of the EU. Those judgments read the exception narrowly.
The test in Article 5(3)
An airline is not obliged to pay compensation “if it can prove” that the cancellation was caused by extraordinary circumstances which could not have been avoided even if all reasonable measures had been taken (Art. 5(3), Regulation 261/2004). The same defence applies to delays of three hours or more (CJEU, Sturgeon, C-402/07).
The airline has to prove two separate things.
1. The event was extraordinary. It must be an event that, by its nature or origin, is not inherent in the normal exercise of the airline’s activity and is beyond its actual control (CJEU, Wallentin-Hermann, C-549/07). Both parts are required.
Recital 14 gives examples such as political instability, weather, security risks, unexpected flight safety shortcomings and strikes, but the Court has held that these are only indications: each still has to pass the test.
2. The disruption could not have been avoided. The airline must show that even by using all the staff, equipment and money at its disposal it clearly could not have prevented the event from causing the cancellation or delay, short of intolerable sacrifices for its business (C-549/07).
It must plan with a reserve of time (CJEU, Eglītis, C-294/10) and re-route passengers by the earliest available means, including other airlines (CJEU, TAP, C-74/19).
There must also be a direct causal link between the event and your flight. An event affecting an earlier rotation of the same aircraft can count, but only if the airline proves that link (C-74/19).
What usually counts and what does not
| Event | Extraordinary? | Case or basis |
|---|---|---|
| Weather making the flight unsafe; airport or airspace closure | Yes | Recital 14; McDonagh, C-12/11 |
| Air traffic management decision affecting the flight | Yes | Recital 15 |
| Bird strike | Yes | Pešková, C-315/15 |
| Lightning strike requiring a mandatory inspection | Yes | AirHelp v Austrian Airlines, C-399/24 |
| Tyre damaged by debris on the runway | Yes | Germanwings v Pauels, C-501/17 |
| Fuel spilled on a runway, closing it | Yes | Moens, C-159/18 |
| Hidden manufacturing or design defect revealed by the manufacturer or an authority | Yes | Wallentin-Hermann, C-549/07; Finnair, C-385/23 |
| Unruly passenger forcing a diversion | Yes, unless the airline contributed to it | TAP, C-74/19 |
| General failure of the airport’s refuelling system | Yes | SATA International, C-308/21 |
| Shortage of airport-operator staff loading baggage | Can be, if beyond the airline’s control | Touristic Aviation Services, C-405/23 |
| Strike by air traffic controllers or airport staff | Yes, as an external event | Airhelp v SAS, C-28/20 |
| Technical fault found in maintenance or pre-flight checks | No | Wallentin-Hermann, C-549/07 |
| Unexpected premature failure of a component | No | van der Lans, C-257/14 |
| Collision with mobile boarding stairs | No | Siewert, C-394/14 |
| Strike by the airline’s own pilots or cabin crew | No | Airhelp v SAS, C-28/20 |
| Wildcat strike after a restructuring announcement | No | Krüsemann, C-195/17 |
| Crew member suddenly ill or deceased | No | TAP, C-156/22; Lipton [2024] UKSC 24 |
| Reorganising flights after an earlier disruption, leading to denied boarding | No | Finnair v Lassooy, C-22/11 |
Each topic has its own page: bad weather, strikes and technical problems.
What stays owed
Good to know
Extraordinary circumstances remove only the fixed compensation of €250 to €600 (£220 to £520 under UK261).
The airline still owes:
- Care: meals, drinks, communications and a hotel with transfers when needed (Art. 9), with no exception for exceptional events (CJEU, McDonagh, C-12/11)
- Refund or re-routing: the choice between a refund within seven days and re-routing at the earliest opportunity (Art. 8)
See flight cancellation and flight delay.
How to challenge a refusal
- Ask for specifics. Request, in writing, the event relied on, when and where it happened, how it affected your flight, and what the airline did to avoid the delay or to re-route you sooner. Quote Art. 5(3): the burden of proof is the airline’s.
- Check the facts. Compare other departures from the same airport at the same time. Check whether the event concerned your flight or an earlier one, and how many hours lay between them.
- Match the event to the table. If the airline describes a technical fault, crew shortage, crew sickness or a strike by its own staff, cite the case and repeat the claim.
- Test the second condition. Even with a real extraordinary event, ask what reasonable measures were taken. A next-day flight on the same airline, when another carrier flew that evening, does not meet the standard in TAP (C-74/19).
- Escalate. If the airline still refuses, the options are the national enforcement body, an alternative dispute resolution scheme where the airline belongs to one, or a small-claims court. The steps and deadlines are in how to claim, and the wording in our claim letter. Claims companies are another route.
From 23 October 2027: a definition and a list
Regulation (EU) 2026/2202, adopted in 2026, applies from 23 October 2027. It writes the case-law test into the regulation as a definition and adds, in a new Article 6c and annex, a non-exhaustive list of extraordinary circumstances. The list covers, among others:
- Natural disasters.
- Unsafe weather.
- War.
- Unruly passengers.
- Medical emergencies.
- Sabotage.
- Hidden manufacturing or design defects.
- Air traffic management restrictions.
- Unscheduled airport closures.
- Strikes at essential service providers.
- Damage caused by third parties, animals or foreign objects.
Three points in the new text help passengers:
- The airline must prove a direct causal link between the event and the disruption.
- When refusing a claim it must say which listed circumstance it relies on and explain how the conditions are met.
- It must answer a request for compensation within 30 days.
Good to know
Flights before the date of application are judged under the current rules described above.