STC ST04481CH
FAA DRS lists ST04481CH as Current · Issued, held by Butler National Corporation, for Learjet 35, Learjet 35A (C-21A), and Learjet 36, and 1 more aircraft configuration. Recorded change: Replacement of similar functioning circuit and switch for obsolete steering interface unit (SIU) in accordance with Butler National Master Data List 0200 I 020 Revisio n (A) , dat ed 14 MAY 2021, or later FAA Approved Revision. Snapshot dated June 30, 2026.
Recorded modification
What the FAA record covers
ST04481CH 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: Learjet 35, Learjet 35A (C-21A), and Learjet 36, and 1 more aircraft configuration. Confirm the approved model list, serial effectivity, configuration, and certificate revision.
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Related other aircraft modifications STCs
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Installation of TSO-C127 Economy Class Seats.
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