Address for FAA Form 337's
(Summerfield, FL. USA)
What address do I mail the FAA Form 337 for a newly installed supplemental type certificate (STC)?
ANSWER: Completed forms should be submitted to the Aircraft Registration Branch, AFS-750, PO Box 25504, Oklahoma City, Oklahoma 73125.
Electronic forms are submitted automatically through the website at:
This information is located in AC 43.9-1F which can be downloaded from the Advisory Circular section of this website.
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