Originally Posted by
corporate-wage-slave
It's a grey area and can be argued both ways. Removing sick passengers is an inherent activity, and BA's rules regarding unaccompanied luggage are what they are. The bar is now quite high, birdstrike is no longer considered exceptional since that's also inherent. Personally I wouldn't bother with this, unless I had a massive sense of grievance, and a district judge may well be sympathetic to the airline, or may not be sympathetic. Given it's 4 minutes over, and assuming BA handled it as well as they could I'd let it rest, but you are liberty to take it further if you are so minded.
If this came up 3 years ago I doubt an English court would have found in your favour. Now I'm not so sure.
I would question the premise that one should cut and calculate whether X minutes are attributable to this, that or the other. IMO, the test is a simple but for-type test: would the passenger have arrived within the set time but for the delay to the incoming aircraft? Since the answer to this is "yes", then compensation is due. IMO, it is no different to the aircraft missing its departure slot and then having to wait a very long time due to congestion: this would not exculpate the airline, imo. But I do agree that this is not a slam dunk either way.