FAR 21.614 — TSO Transferability
FAR 21.614 explains that TSO authorizations and letters of TSO design approval cannot be transferred. Learn what this means for pilots and manufacturers.
In Plain English
FAR 21.614 is a short but important rule in the certification world. It states that if a manufacturer holds a TSO authorization (Technical Standard Order authorization) or a letter of TSO design approval, that approval cannot be transferred to another party.
In plain terms:
- A TSO is an FAA-issued minimum performance standard for specific articles (like avionics, seatbelts, or oxygen masks) used on civil aircraft.
- When a manufacturer earns a TSO authorization, it's tied specifically to that manufacturer — not to the part itself or to a buyer of the company's assets.
- If another company wants to produce the same article under TSO, it must apply for and obtain its own TSO authorization.
Why it matters operationally: As a pilot, you generally won't deal with TSO paperwork directly, but understanding this rule helps you grasp why TSO-marked parts are linked to a specific manufacturer and why substitutions during maintenance must come from properly authorized sources.
Regulation Text
14 CFR § 21.614§ 21.614 Transferability.
The holder of a TSO authorization or letter of TSO design approval may not transfer the TSO authorization or letter of TSO design approval.
Oral Exam Questions a DPE Might Ask
Q1Can a manufacturer sell or transfer its TSO authorization to another company?
No. Per FAR 21.614, the holder of a TSO authorization or letter of TSO design approval may not transfer it to anyone else.
Q2If Company A acquires Company B, which holds a TSO authorization, does Company A automatically gain that authorization?
No. FAR 21.614 prohibits transfer of TSO authorizations, so Company A would need to apply for and obtain its own TSO authorization.
Q3Does FAR 21.614 apply to both TSO authorizations and letters of TSO design approval?
Yes. FAR 21.614 expressly states that neither a TSO authorization nor a letter of TSO design approval may be transferred by the holder.
Studying for a checkride?
Related Sections in Part 21