For information regarding the supplemental type certificate application process, contact the FAA Aircraft Certification Office (ACO) in your geographic area.  The “Application Guide for Obtaining a Supplemental Type Certificate,” and other related advisory, policy and guidance information is available on the STC Regulations & Policies page.

For information regarding the “One-only” STC application process involving non U.S. registered aircraft, where the U.S. is the State of design, see Order 8110.4, paragraph 4-15c.

STC process - major steps, as required

• Applicant applies for STC
• Familiarization and preliminary type certification board (TCB) meetings
• FAA develops certification program plan
• Establishment of certification basis by FAA
• Applicant submits data for approval
• FAA design evaluation
• FAA and applicant hold specialists and interim type certification meetings, as required
• FAA performs conformity inspections
• Engineering compliance determinations
• Pre-flight TCB Meeting
• Applicant performs ground inspections, ground tests, and flight tests
• FAA reviews manufacturer's flight test results and issues TIA
• FAA performs conformity inspections, witnesses tests, performs official certification flight tests and flight standards evaluations
• Functional and reliability testing
• FAA approves flight manual supplement or supplemental flight manual and holds final TCB meeting
• AEG completes continuing airworthiness determination
• FAA issues STC

An STC will be issued only if:

• the pertinent technical data have been examined and found satisfactory,
• all necessary tests and compliance inspections have been completed, and
• the alteration has been found to conform with the technical data.&

An STC will not be issued to:

• approve minor changes, or for approval of identical replacement parts, unless the installation of such parts constitutes a major change to the type design
• approve design changes to Technical Standard Order (TSO) approved articles unless the TSO is invalidated for the modified article. An STC which modifies a TSO article must provide for installation
• combine two or more STCs without additional showing of compliance; or
• manufacturers or applicants outside of the U.S., except as provided for in a bilateral agreement.