STC SA18NW
FAA DRS lists SA18NW as Current · Reissued, held by Sierra Industries Inc, for Textron Aviation 421, Textron Aviation 421A, and Textron Aviation 421B. Recorded change: Installation of Fowler flaps, flap actuated drooped ailerons, flap actuated elevator trim and anti- servo rudder trim tab. Snapshot dated June 30, 2026.
Recorded modification
What the FAA record covers
SA18NW 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 421, Textron Aviation 421A, and Textron Aviation 421B. Confirm the approved model list, serial effectivity, configuration, and certificate revision.
Related flight controls STCs
Installation of Fiberglass rudder post mount for either Grimes or Whelen WRM rotating beacons.
FAA holder: Univair Aircraft Corporation
Installation of the Garmin GFC 700 Automatic Flight Control System.
FAA holder: Garmin International Inc
Fabrication of Spoilers, Inc. Model SP1000UG spoiler system.
FAA holder: TRM Avionics Logistics Inc
Installation of aluminum elevator skins in place of magnesium elevator skins.
FAA holder: SRS Aviation LLC
FAA record reference
- STC number
- SA18NW
- Product
- Aircraft · Small Airplane
- Country
- United States
- Application date
- March 29, 1972
- Revision date
- July 31, 2017
- CFR references
- Part 3, Part 21