How many STCs on a 337 form?


Well-Known Member
Talking with my IA today he wants only 1 stc on a 337. In the pass if I did several mods I would put 3 or 4 stcs on one 337.

Has anyone very heard that that is how the faa wants them done?

Roger Roger

Paid to sleep, fly for fun
One mod, one form. Major repairs might get combined because let's say you rebuilt a stabilizer you might have repaired the stabilizer spar, replaced a skin, and replaced the hinge fitting all as part of the repair. But mods especially per an STC one per form.


Well-Known Member
I typically do 1 to 1, but in the case where more than one related STC is applied at the same time I might put them on the same form. For instance, we installed pulselites, wingtips, and recognition lights, and we opted for HID lights, the wingtips/lights were one STC but the HID option was a separate STC and the pulselite system was a third STC. I put all three of those on one form.