STC SA1663NM
FAA DRS lists SA1663NM as Current · Reissued, held by Sierra Industries Ltd., for Textron Aviation 421C. Recorded change: Addition of fowler wing flaps, elevator trim spring with cockpit tension select lever, fuselage strakes, and nacelle strakes. Snapshot dated June 30, 2026.
Recorded modification
What the FAA record covers
Addition of fowler wing flaps, elevator trim spring with cockpit tension select lever, fuselage strakes, and nacelle strakes.
SA1663NM identifies the approval, recorded holder, named aircraft, and modification scope. It does not confirm kit availability, serial-number effectivity, data rights, price, or installation authority.
Applicability
Aircraft named in FAA DRS
Named aircraft: Textron Aviation 421C. Confirm the approved model list, serial effectivity, configuration, and certificate revision.
Buyer checks
Confirm before sourcing
- 01Does it cover the exact Textron Aviation 421C model, serial range, and configuration?
- 02Which powerplant configuration, limits, instruments, and maintenance data apply?
- 03Who can legally supply the design data, kit, instructions, and ICAs?
- 04What parts, labor, conformity, and return-to-service work are excluded?
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