Supplemental Type Certificates (STC) are FAA approvals for type design change to an aircraft. Essentially, STCs modify the aircraft Type Certificate (TC) to certify a modification to the aircraft in the aftermarket.
There are two primary paths to achieve certification via FAA STC: work directly with the FAA and your local Aircraft Certification Office (ACO); or, work with an ODA holding STC approval authorization.
Yes – there are many ODA types, of those, the two primary ODAs are those that hold Type Certificate (TC) approval authority, and those, like Delta Engineering, that hold Supplemental Type Certificate (STC) approval authority, among other attributes.
Delta Engineering, as an FAA ODA, has been granted No Project Notification Letter (No-PNL) approval authority due to the trust placed in us by the FAA. This means that Delta Engineering can complete specific project types with no FAA involvement.
Due to the trust the FAA has placed in us, when we complete No-PNL projects without FAA involvement, a record of the project must be kept. The FAA completes routine supervision audits to ensure correct function by our organization.
Typically, the project starts with design including installation and part drawings, and then engineering to substantiate installation and find compliance with FAA regulations. Finally, installation, testing and conformities are completed at aircraft before the STC is issued.
A PMA part is a production part that is manufactured to a specific drawing and revision, whereas a Production Certificate (PC) allows the manufacturer to produce the part to the drawing and revision per the FAA STC associated with the part.
To install a new article in an aircraft, it must be approved, for example via an STC, it must have the proper qualification (i.e. DO-160, TSO, etc) and it must be manufactured via an approved methodology (i.e. PC, PMA).
Qualification is the substantiation that new aircraft equipment will not fail in a manner which may cause adverse effects to the aircraft or aircraft systems. Qualification can be completed via analysis, comparison or testing such as DO-160.
Foreign Civil Aviation Authorities (CAAs) typically organize agreements with the FAA called bi-lateral agreements, depending on the terms of these agreements, FAA STCs can be validated for CAAs around the world after completion.