AAM Glossary
What Is FAA Part 135 Certification?
Part 135 refers to the section of the federal aviation regulations under which on-demand commercial air carriers are certificated and operate. Where scheduled airlines fly under their own, more extensive framework and private owners fly under general operating rules, Part 135 covers the commercial middle ground: charter flights, air taxis, medical transport, and smaller cargo operations that carry paying customers without running large scheduled networks. Certification under it is what legally transforms an aircraft operator into a commercial air carrier.
What does Part 135 certification cover?
The certificate belongs to the operator, not to an aircraft. To earn it, a company must demonstrate to the FAA that it can run a safe commercial operation as an organization: qualified management personnel in defined roles, approved training and checking programs for pilots, maintenance and inspection programs for every aircraft on the certificate, operational control procedures that determine who may release a flight, and manuals documenting all of it. Crew qualification, duty and rest limits, weather minimums, and equipment requirements are all more demanding than for private flying.
Certification is a staged process. An applicant works through formal phases of application, documentation review, and demonstration, with the FAA evaluating conformance before issuing the certificate and the operations specifications that define exactly what the carrier may do — which aircraft, which kinds of operations, and where.
Why does Part 135 matter for Advanced Air Mobility?
Air taxi service is a commercial, on-demand passenger operation — precisely the kind of flying this framework was built to govern. Companies planning eVTOL passenger or cargo service are therefore generally expected to hold operator certification under it, or to partner with carriers that do, in addition to the separate type certification the aircraft itself requires. For infrastructure and route planners, operator certification defines which missions can legally be flown from a vertiport, making it a gating item in any deployment timeline.
Frequently asked questions
Is Part 135 about the aircraft or the operator?
The operator. Aircraft designs are approved separately through type certification. A Part 135 certificate authorizes a company to conduct commercial operations, and each aircraft it uses must be listed on the certificate and maintained under the carrier's approved programs.
How is Part 135 different from the rules airlines fly under?
Scheduled airlines operate under a separate, more extensive framework built around large scheduled networks. Part 135 is scaled for on-demand and commuter operations — smaller aircraft, chartered missions, air ambulance, and air taxi service — with requirements proportionate to that kind of flying.
Will eVTOL air taxis need Part 135 certification?
On-demand commercial passenger service falls squarely within this framework's territory, so eVTOL air taxi operators are generally expected to be certificated under it or to fly under an existing carrier's certificate. The aircraft additionally needs its own design approval through type certification.
Related terms
An air taxi is an on-demand passenger air service: small aircraft, typically vertical-lift, hired per trip to fly point-to-point rather than on a fixed airline schedule. The term names the service model, not an aircraft type.
Type certificationType certification is the process by which an aviation authority approves an aircraft design as compliant with airworthiness standards, after the manufacturer demonstrates through analysis, ground testing, and flight testing that the design is safe.
eVTOLAn eVTOL is an aircraft that takes off, hovers, and lands vertically using electric or hybrid-electric propulsion, pairing the runway independence of a helicopter with the redundancy of distributed electric motors.