If it is covered by the Sale of Goods Act (as amended) your remedies are a whole or partial refund.
http://www.dti.gov.uk/consumers/fact...page24700.html. The Supply of Goods and Services Act is covered here
http://www.dti.gov.uk/consumers/fact...page24702.html - you can ask for a whole or partial refund or ask them to put the situation right. If the FTO disagrees with you you will have to sue for damages.
You can complain to the local trading standards. The CAA will not be interested unless the terms of the FTO's approval have not been complied with or if there has been illegal activity - and even then be aware:
(1) there are often two sides to a story - although you may feel hard done by not everyone will agree with you.
(2) the CAA rarely take any action