FAR 21.179 — Airworthiness Certificate Transfer

FAR 21.179 is one of the shortest rules in Part 21, but it answers a question that comes up constantly in real-world aircraft transactions and on checkrides: what happens to the airworthiness certificate when an aircraft is sold?

The answer is simple — the airworthiness certificate is transferred with the aircraft. It stays with the airframe, not with the previous owner.

Why this matters operationally:

• When you buy a used aircraft, you do not need to apply for a new airworthiness certificate just because ownership changed.
• The certificate must remain on board and displayed at the cabin or cockpit entrance so it's visible to passengers and crew (per FAR 91.203).
• The registration certificate, by contrast, does not transfer — a new owner must apply for a new registration.
• If the aircraft is later modified, damaged, or falls out of compliance with its type design, the airworthiness certificate can become invalid even though it was lawfully transferred.

For a student pilot, the takeaway is to remember the distinction: airworthiness goes with the aircraft, registration goes with the owner.