Plain English Meaning

Permission from the FAA to fly an aircraft that is not legally airworthy at the moment, so it can be flown somewhere to be fixed or inspected. The aircraft still has to be safe to fly — it just isn't fully legal to fly under normal rules.

Full Definition

A Special Flight Permit is an authorization issued by the FAA that allows an aircraft which does not currently meet applicable airworthiness requirements, but is capable of safe flight, to be flown to a location where repairs, alterations, maintenance, or required inspections can be performed. It is commonly known as a ferry permit and is issued under 14 CFR Part 21.

Context Anchor

Pilots encounter this when an aircraft needs to be legally flown even though it cannot be used for normal operations, such as flying it to a maintenance facility after a problem is found.