Wallentin-Hermann ruling: CJEU dismisses the technical issue excuse

The Wallentin-Hermann v Alitalia Linee Aeree Italiane SpA ruling, delivered by the Court of Justice of the European Union on 22 December 2008 (Case C-549/07), is probably the most cited and powerful decision in favour of European air passengers. In a single decision, the Court stripped airlines of their favourite excuse: "there was a technical issue."

The facts: a flight cancelled for engine failure

Mrs Friederike Wallentin-Hermann booked an Alitalia Vienna–Brindisi flight with connection in Rome for herself, her husband and her daughter on 28 June 2005. Five minutes before departure, the flight is cancelled. The passengers are transferred to an Austrian Airlines flight then to Air One. They arrive in Brindisi 3 hours 30 late.

Alitalia's stated cause: a complex turbine failure, detected during a pre-flight check. The airline refuses compensation, invoking extraordinary circumstances under Article 5(3) of Regulation (EC) 261/2004.

Mrs Wallentin-Hermann seizes the Vienna Commercial Court, which refers a preliminary question to the CJEU on the interpretation of extraordinary circumstances.

The decision: a technical failure is NOT an extraordinary circumstance

On 22 December 2008, the CJEU delivers a crystal-clear ruling in three steps.

1. Extraordinary circumstance is to be interpreted strictly

The Court recalls that this is a derogation from the compensation principle. As any derogation, it must be interpreted strictly (paragraph 17). Airlines therefore cannot extend its scope through expansive interpretation.

2. The test: externality + effective control

The Court sets a dual criterion (paragraph 23):

• The event must be external to the normal activity of the air carrier.
• It must escape its effective control.

Both conditions are cumulative. If the event is inherent to operations, it is not extraordinary, even if unforeseen.

3. The verdict: technical failure is inherent to operations

At paragraph 24, the Court states the principle that changed everything:

"Technical problems which come to light during maintenance of aircraft or on account of failure to carry out such maintenance cannot constitute, in themselves, 'extraordinary circumstances' under Article 5(3) of that regulation."

The Court specifies: aircraft maintenance is an activity inherent to the air carrier's business. A mechanical failure is just a manifestation of that internal risk, not an exceptional external event.

When can a failure still be extraordinary?

At paragraph 26, the Court recognises three exceptions, strictly construed:

1. A hidden manufacturing defect revealed by the manufacturer, affecting the safety of an aircraft type (manufacturer's service bulletin received same day).
2. An act of sabotage on the aircraft, foreign to the airline's activity.
3. An act of terrorism.

The Court adds an additional condition (paragraph 41): even in these cases, the airline must prove "they could not have been avoided even if all reasonable measures had been taken". Meaning that even a manufacturer's defect, but one that could have been detected in time with prudent maintenance, will not suffice.

Practical consequences: 90% of technical refusals are contestable

Before Wallentin-Hermann, airlines en masse refused compensation by invoking a generic technical problem. After the ruling, this excuse became legally very fragile.

In practice, most refusals rely on vague statements like:

• "Aircraft technical problem"
• "Unscheduled maintenance"
• "Defect detected during pre-flight inspection"
• "Faulty part"

These grounds are almost always rejected by national courts when the passenger contests with Wallentin-Hermann case law.

The van der Lans ruling (2015) — the confirmation

The van der Lans v KLM ruling (CJEU, 17 September 2015, C-257/14) confirmed Wallentin-Hermann and went even further. The Court held that an unexpected and hidden part failure is also not an extraordinary circumstance, as long as it remains linked to operations. KLM had invoked an unforeseeable failure: not enough.

This case law was confirmed by other rulings (Germanwings v Pauels, Moens, Niki Luftfahrt…) drawing a clear line: internal maintenance can never be extraordinary; only external causes (bird, nail on runway, sabotage…) can be.

How to use Wallentin-Hermann to contest a refusal

If an airline refuses compensation for a delay or cancellation by invoking a technical issue, here's the playbook:

1. Request in writing the detailed nature of the alleged technical issue. An airline cannot rely on a generic "technical problem."
2. Verify the nature of the defect. If it's internal maintenance (worn part, engine failure, hydraulic, on-board electronics…), Wallentin-Hermann applies fully.
3. Send a formal letter citing the case law: "Under the Wallentin-Hermann ruling (CJEU, C-549/07), a technical issue inherent to operations is not an extraordinary circumstance under Article 5(3) of Regulation (EC) 261/2004."
4. If refusal persists, seize the competent court or a professional service like Robin des Airs.

Summary

To check whether your case is covered by this case law, use our claim simulator or contact us on WhatsApp.

Related articles

• Full CJEU case law on Regulation EC 261
• Extraordinary circumstances: what counts and what doesn't
• Airline refuses your claim: next steps
• Cancelled flight: up to €600 compensation