The short answer
A ferry permit — formally a Special Flight Permit — is an FAA authorization to fly an aircraft that doesn't currently meet all applicable airworthiness requirements, for a specific purpose such as flying to a maintenance facility. It's issued for defined flights with conditions and limitations.
Typical uses
Common cases: an inspection has lapsed and the aircraft needs to reach a shop, an aircraft is being moved after purchase, or a repair must be completed at another field. The FAA (or an authorized DAR) issues the permit after determining the aircraft is capable of safe flight for that operation, often with conditions — daytime VFR only, crew only, specific routing.
A ferry permit doesn't waive maintenance requirements; it narrowly authorizes specific flights so the underlying items can be addressed.
Related terms and reading
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