STC ST09992SC
FAA DRS lists ST09992SC as Current · Issued, held by Underwood - Instrument Services, Inc., for Learjet 24, Learjet 24A, and Learjet 24B, and 8 more aircraft configurations. Recorded change: Replace existing production installed S-225 series Mach Airspeed Indicators with REVUE THOMMEN AG Type 5C18.22.65K.00.0 Mach Airspeed Indicators. Snapshot dated June 30, 2026.
Recorded modification
What the FAA record covers
ST09992SC 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 24, Learjet 24A, and Learjet 24B, and 8 more aircraft configurations. Confirm the approved model list, serial effectivity, configuration, and certificate revision.
Buyer checks
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