Originally Posted by
Often1
According to the OP, there was no "technical fault" located and the cancellation was presumably precautionary because no such fault could be located. Here are two examples, both of which are speculative exactly because we do not have facts and exactly why OP ought to go through at least one more round of fact-gathering with BA:
1. Clearly there was a smell of fuel. This dictates the precaution of off-loading the aircraft and determining whether there was an going danger to the aircraft which would preclude it from flying safely. But, no such danger was apparent and thus the flight was cancelled, presumably because a lengthy review of every system was likely in order. Perhaps the ground HVAC sucked in some random fumes? Perhaps nothing was wrong? Who knows. But, safety comes first and the incident means a careful review. Perhaps after that review, no "technical fault" was ever found.
I would hope that any sensible person, even one of the EU nannies, looking at this situation would not penalize a carrier for being too cautious.
The purpose of the regulation is not to punish the carrier, but to compensate the passenger for his delay. See Huzar v. Jet2.com:
Originally Posted by Court of Appeal
40. Second, Mr Lawson emphasised the deterrent effect of the Regulation. I would accept that if the purpose of compensation were purely to deter carriers from adopting bad practices, there would be some force in the construction which he urged upon us. But whilst that is no doubt an important function of the Regulation, it does not express the full range of its objectives as enunciated in recitals 1 to 4, and I do not believe that Advocate General Bot in Finnair was intending to suggest otherwise. The wider purpose is to compensate passengers for inconvenience, as the recitals make clear, and it is far from self evident that this requires compensation to be limited to cases of fault.
http://www.bailii.org/ew/cases/EWCA/Civ/2014/791.html
If you look at the rest of the judgement, to which the Supreme Court declined to hear an appeal, the Court clearly expects carriers to entertain EU261/2004 compensation claims as a cost of doing business where unexpected technical delays can arise.
36. ... As the CJEU recognised in paragraph 24 of Wallentin-Hermann, difficult technical problems arise as a matter of course in the ordinary operation of the carrier's activity. Some may be foreseeable and some not but all are, in my view, properly described as inherent in the normal exercise of the carrier's activity. They have their nature and origin in that activity; they are part of the wear and tear. ...
Originally Posted by
Often1
2. There are stations where the fuel concession is the airport authorities. Eg., the bowsers are not contracted to BA. If there were a leak from a bowser, that is not only the fault of the airport authority, but not the fault of BA, which doesn't bear any more responsibility here than it does if you slip and break your ankle walking to the gate due to a failure of the airport authority.
The supply of fuel is surely "inherent in the normal exercise of the activity of the air carrier" (to quote the important words from Walletin-Hermann), and was contracted out to the airport by the carrier and therefore not beyond the carrier's control. I suspect some judges would be quite sympathetic to including it in a delay claim, and not sympathetic to enable contracting-out to function as a device for evading liability.
(IANAL!)