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.
Buyer checks
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