The STC search system is a complimentary service provided to the aviation community. We hope you find it useful. We do not provide access to STC engineering. For that you need to contact the STC holder directly. Our primary product is a comprehensive library of aviation regulations and standards, including tools for generating Airworthiness Directive compliance reports.

No. of STCs: 4

STC Holder: Yehnert Helicopters, Inc 1049 Airport Drive, Upland, CA 91786, United States		If you are an STC Holder, Contact us to have your company added here!
STC No.: SE78WE	Status: Current	App Date:	Rev Date: 08/11/1976
Description: Install two locking pins in Franklin Part Number 21014J oil transfer collar, 180 degrees apart, to prevent rotation of oil seal in collar.
TC Nos.: E9EA
Models: Wytwornia Sprzetu Komunikacyjnego6A-350-C1, 6A-350-C1A, 6A-350-C2
ACO: AIR-770: West Certification Branch LA

STC Holder: Yehnert Helicopters, Inc 1049 Airport Drive, Upland, CA 91786, United States		If you are an STC Holder, Contact us to have your company added here!
STC No.: SH3556NM	Status: Current	App Date:	Rev Date: 12/17/1986
Description: Installation of low profile instrument panel.
TC Nos.: H3WE
Models: MD Helicopter Inc.369D, 369H, 369HE, 369HS
ACO: AIR-770: West Certification Branch LA

STC Holder: Yehnert Helicopters, Inc 1049 Airport Drive, Upland, CA 91786, United States		If you are an STC Holder, Contact us to have your company added here!
STC No.: SH4544NM	Status: Current	App Date:	Rev Date: 08/31/1994
Description: Modification of engine inlet fairing.
TC Nos.: H3WE
Models: MD Helicopter Inc.369E
ACO: AIR-770: West Certification Branch LA

STC Holder: Yehnert Helicopters, Inc 1049 Airport Drive, Upland, CA 91786, United States		If you are an STC Holder, Contact us to have your company added here!
STC No.: SR00135LA	Status: Current	App Date: 11/22/1994	Rev Date: 12/15/1995
Description: Installation of Yehnert Tail Rotor Blades YH-278 as replacements for Hiller Tail Rotor Blades 55073.
TC Nos.: 4H10, 4H11
Models: Hiller AviationUH-12D (Army UH-23D) Rogerson Hiller CorporationUH-12E, UH-12E-L
ACO: AIR-770: West Certification Branch LA