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An aircraft requiring modification or repair may be 'grounded' until the necessary work has been completed and the aircraft is once again fit for flight.

In many cases the work is concluded within a few days and the Certificate of Airworthiness (C of A) or Permit to Fly will be re-validated by the maintenance organisation responsible.

However, in some cases the aircraft may be grounded for many months. In these circumstances, the aircraft may wish to surrender the C of A or Permit to Fly in order to receive a pro-rata refund on the validation cost.

Before this is decided, the following should be considered:

  • The aircraft may not be flown until a new C of A or Permit to Fly is issued.
  • Refunds made will be relative only to the cost of the C of A or Permit to Fly validation - investigations costs will not be refunded.
  • If a C of A or Permit to Fly is surrendered the next document issued will be a subsequent issue, not a renewal. The fee for a subsequent issue is higher than that for a renewal.

For further advice, please contact the Applications and Approvals Department through apply@caa.co.uk or +44 (0) 330 022 1908.

Out of hours contact information

If technical advice is required out of normal office hours to support UK Air Operator Certificate (AOC) holders for urgent operational reasons the CAA will endeavour to assist wherever possible.

Our out of hours contact number is +44(0) 330 022 1500.

Close Out of hours contact information