The principles clarified in “Wallentin-Hermann” have long since become part of everyday judicial practice. The motivation of the CJEU is clear: it wanted to put a stop to the somewhat too generous interpretation of the narrowly defined criterion of “extraordinary circumstances” at the time. The courts embraced this idea and expanded on it. As a result of this development, delays due to refuelling or problems with the availability of ground handling or flight personnel now share the fate of “engine failures.” The reason behind this is quite straightforward: it falls within the airline’s sphere of risk whether its aircraft are fully operational. The practice did not stop there. Courts extend this idea (mostly relying on the somewhat fitting recital 6 of the regulation) to any activity that an airline could theoretically perform. Handling of baggage and aircraft maintenance, for example, could also be done by the airline itself, which is why the activity of the airport is considered the work of the airline and therefore within its control. This is particularly relevant for the recurring de-icing of aircraft in winter or delays due to ground handling.

Furthermore, regulatory or (perceived) frequently recurring measures are now also considered framework conditions for air travel by the judiciary. It must be convincing under constant conditions that affect every airline without exception. These include so-called “night flight bans” or nearly ubiquitous climatic conditions (such as freezing temperatures in winter). This development becomes difficult when it contradicts the rule/exception ratio in the wording of the recitals:

Recital 14 of the regulation generally recognises “extraordinary circumstances” in weather conditions and safety risks that are not compatible with the operation of the relevant flight. The legislator likely recognised that humanity has always been subject to weather conditions since the beginning of time. Therefore, he restricted the “rule of exception” to weather conditions that make the execution of a flight no longer justifiable. This is consistent because weather always possesses an unpredictability for humans. Planning for such things in daily business is simply not entirely reliable. The legislator’s perspective here was therefore on air travel in general, not on business on individual routes or airports. Nevertheless, some courts now go so far as to deny certain weather phenomena, either in specific regions or generally (especially thunderstorms), the character of an extraordinary circumstance. For an airline, this means it must present in these cases the conditions under which certain weather phenomena arise and, if necessary, the geographical conditions of airports and flight routes in a well-founded manner. If geography particularly favours certain weather conditions, the airline must either describe planning measures to mitigate the effects (which will rarely be possible with geographical conditions) or explain to what extent the weather conditions were not favoured by the geographical location or the court does not understand the corresponding weather correctly or too broadly.

This must be countered. For airports located in geographically unfavourable locations, incentives are thus created to disconnect them from the supply network because an airline would effectively be exposed to liability for a guarantee in such airports. An airline does not always have a choice in such cases.

Also problematic is the development regarding strikes. Even though Recital 14 generally recognised these as extraordinary circumstances, this can de facto only be said for a strike by security personnel and air traffic controllers – both tasks in the hands of the state. In the case of all other strikes, courts usually arrive at them through the attribution to framework conditions of air transport – either because airport personnel were affected or because labour and collective bargaining conditions (sometimes also company-wide) belong to the general economic conditions of a company. This cannot be reconciled with a genuinely air traffic-oriented understanding and was not intended as such according to Recital 14.

Finally, attention should be drawn to the measures of air traffic management laid down in Recital 15. Last year, the average delay of a flight due to air traffic control regulations (similar to the “record flight year” 2019) was 1.8 minutes. This remarkably low number is due to the fact that air traffic control receives detailed flight plans in advance and efficiently arranges aircraft routes with various flight sectors. The system works so well that delays due to regulatory measures in view of aviation as a whole are practically the exception – especially those that lead to delays of over three hours or even cancellations. The legislator rightly recognised them as extraordinary circumstances. Judicial practice reverses this rule/exception ratio through mountains of documents, which are further inflated by a litigation practice focused on the fragmentation of flights by legal service providers. It is humanly understandable, but legally unsustainable, to assume in such a perception that delays due to air traffic control measures represent an expected framework condition. Wallentin-Hermann therefore presents an airline with two main challenges in the near future: firstly, it must be able to counter the assumptions of plaintiffs and courts on both a psychological and factual level, and secondly, it must create an awareness of the regulatory background of air travel.