Fri Jul 21, 2017 6:23 pm
Well, I can speak for a US experience on Frontier (which re-structured as an ULCC): And it really sucked:
The aircraft had squelch problem with one of the radios when everyone was on board (on a brand-new A320). They tried to control-alt-delete the aircraft. We were delayed 2 hours while the mechanics tried to swap it out. [Being the pilot geek I am, I was in the cockpit during startup, and saw the radio continued to squelch after the APU spun-up. The Captain gave me the "thumbs down" sign]. I went back to my seat, telling my seatmate "we're not going anywhere on this plane". But we were only off-boarded over an hour later.
None of us could re-booked of other airlines, because Frontier had no agreements to be able do so.
Eventually, another F8 aircraft arrived 14 hours after of our scheduled departure time. It was "wheels up" after a total delay of 16 hours. (I missed a critical meeting, as a result). I had a $10 meal voucher in the meantime... And successful departure was late into the next morning.
My compensation: A month later, I got an apology e-mail from Frontier, with $100 voucher to be put towards another Frontier flight -- and only good for 90 days. Needless to say, I didn't use it.