Not every unexpected event lets an airline off the hook. The Court of Justice of the EU has drawn a genuinely strict, and often counterintuitive, line around what actually qualifies.
The Myth
"Airlines can dismiss EC261 or UK261 compensation claims simply by stating the delay was caused by an unexpected mechanical breakdown."
For how the CJEU treats airline staff strikes specifically — a related but distinct question — see our EC261 regulatory guide. This article covers the broader classification system the CJEU has built, with a focus on technical defects and the evidence you need to challenge a false "extraordinary circumstances" claim.
The Reality
Under EC261 and UK261, once a flight arrives 3+ hours late at its final destination, compensation is mandatory unless the carrier meets a genuinely strict burden of proof for "extraordinary circumstances." Routine technical failures, unexpected component defects, and staff shortages are legally classified as an inherent part of operating an airline — not something outside its control.
The Legal Classification: What Does and Doesn't Exempt the Airline
Does NOT exempt the airline (compensation remains mandatory):
- Airline staff strikes (pilots, cabin crew, ground staff)
- Technical defects discovered during pre-flight maintenance
- Crew shortages or duty-time limits caused by an earlier delay
- Aircraft damage caused by mobile boarding stairs or baggage carts
DOES exempt the airline (genuine extraordinary circumstances):
- Air Traffic Control ground stops and flow restrictions
- Severe, unforecasted adverse weather, provable via METAR data
- Political instability or airspace closures
- Hidden manufacturing defects confirmed via an official safety recall from the aircraft manufacturer
Landmark Case: The Technical Component Defense (Wallentin-Hermann, C-549/07)
The scenario: An engine turbine fails complex pre-flight checks, delaying a flight by 6 hours. The airline claims an unforeseen mechanical defect exempted it from paying compensation.
The CJEU ruling: Premature wear or the unexpected failure of an aircraft component is intrinsically linked to the complex operating system of aviation — it's a foreseeable risk of running an airline, not an extraordinary circumstance. The exemption applies only if the defect stems from sabotage or a genuine fleet-wide manufacturing recall, not routine mechanical failure. This is the ruling that most directly undercuts the generic "mechanical issue" excuse airlines commonly cite.
The Protocol: Challenging a False "Extraordinary Circumstances" Claim
- Request the official disruption reason code. Ask the airline for the specific IATA delay code — for example, Code 41 for aircraft technical issues, Code 71 for ATC-related delay. This code is far more specific and harder to dispute in generic terms than a verbal explanation.
- Obtain airport METAR data if weather is cited. Pull the official Meteorological Aerodrome Report for the departure airport to check whether other flights operated normally around the same time — if they did, the "severe weather" claim doesn't hold up.
- Escalate to a National Enforcement Body or ADR. Submit your claim to an approved Alternative Dispute Resolution scheme (CEDR or AviationADR in the UK) or a national aviation authority (AESA in Spain, LBA in Germany) if the airline won't budge.
Use our Flight Status & Evidence Tools directory to pull independent flight-tracking and METAR data before you escalate, and generate a formal compensation letter once you have the reason code and supporting evidence in hand.
Related Kibbo Tools
- Flight Status & Evidence Tools (Directory) →
- Generate a Flight Disruption Compensation Letter →
- Read: EC261 Guide & Strike Jurisprudence →
Sources
- Court of Justice of the European Union — Wallentin-Hermann v. Alitalia, C-549/07. curia.europa.eu
- UK Civil Aviation Authority — Passenger Rights, delay thresholds and ADR schemes. caa.co.uk