Definition
A pilot or instructor certification earned in addition to one already held, granting privileges in a different category, class, or type of aircraft, or in a different kind of instructional activity, without re-issuing the original certificate.
Plain English
An extra rating or qualification added to a certificate you already hold, so you can fly or teach in something new without starting over.
Context Anchor
Seen in training and instructor discussions when a pilot is adding another aircraft type, category, class, or instructor privilege to credentials they already hold.
Derivation
“Add-on” simply means something attached to what is already there. The term is used in FAA documents to describe a qualification that is added to an existing certificate rather than replacing it.
Why Pilots Care
It lets pilots legally take on new types of flying without having to obtain an entirely new certificate from scratch.
Intuition Check
Do not read “add-on” as casual or automatic. In aviation, an add-on certification is still an official FAA qualification with specific requirements.
Example Sentence 1
After earning her single-engine flight instructor certificate, she pursued a multi-engine add-on certification so she could teach in twins.
Example Sentence 2
The instructor recommended starting with an add-on certification for multi-engine before pursuing a commercial certificate.