# N602WC: 1970 San Joaquin Helicopters OH-58C - Status: Valid registration - Airframe: [San Joaquin Helicopters OH-58C](https://openairdocs.org/model/san-joaquin-helicopters-oh-58c) (registry code 7950001, 5 seats) - Engine: [Allison 250-C20C](https://openairdocs.org/engine/allison-250-c20c) (registry code 03082) - Data sheets: [TCDS R00002LA](https://openairdocs.org/tcds/R00002LA) (Blair Helicopter Services Inc.), [TCDS E4CE](https://openairdocs.org/tcds/E4CE) (Rolls-Royce Corporation) (OpenAirDocs) - Serial number: 70-15633 - Year built: 1970 - Type: Rotorcraft - Engine type: Turbo-shaft - Airworthiness: Restricted, agriculture and pest control - Airworthiness date: February 18, 2019 - Certificate issued: March 2, 2018 - Expires: March 31, 2028 - Mode S code: A7D0A4 - Registered owner: [Blair Helicopter Service Inc](https://openairdocs.org/faa-owner/BLAIR%20HELICOPTER%20SERVICE%20INC) - Location: [Lemoore, CA](https://openairdocs.org/faa-place/CA/Lemoore) - Owner type: Corporation - Owner's area on the map: 36.2861° N, 119.8341° W: Placed by OpenAirDocs at the center of ZIP code 93245, within about 6 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based - FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=602WC - Page: https://openairdocs.org/aircraft/N602WC From the FAA registry file of October 24, 2026. ADs below are matched by the registry's airframe and engine model codes. They may apply; each AD's applicability can narrow it by serial number, part number or installed equipment. This is not a compliance determination. ## ADs that may apply (OpenAirDocs): 11 in force ### Matched by airframe (San Joaquin Helicopters OH-58C) - [AD 2014-22-03](https://openairdocs.org/ad/2014-22-03): Main Rotor Drive · Rotorcraft Development OH-58A, OH-58A+, OH-58C and 6 more. Effective Dec 19, 2014 ### Matched by engine (Allison 250-C20C) - [AD 2022-10-06](https://openairdocs.org/ad/2022-10-06): Turbine Section · Rolls-Royce 250-C20, 250-C20B, 250-C20C (T63-A-720) and 9 more. Effective Jun 28, 2022 - [AD 2018-13-01](https://openairdocs.org/ad/2018-13-01): Turbine Governor · Rolls-Royce 250-C10 (T63-A-5), 250-C18, 250-C18A and 24 more. Effective Aug 16, 2018 - [AD 2006-16-04](https://openairdocs.org/ad/2006-16-04): Inspection of the fuel nozzle screen · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 43 more. Effective Sep 7, 2006 - [AD 98-24-28](https://openairdocs.org/ad/98-24-28): Main Fuel Control Bellows · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 36 more. Effective Jan 7, 1999 - [AD 88-17-01](https://openairdocs.org/ad/88-17-01): Fuel Controls · Rolls-Royce 250-B17, 250-B17B, 250-B17C and 26 more. Effective Mar 1, 1989 - [AD 83-03-02 R1](https://openairdocs.org/ad/83-03-02-R1): Slotted Third Stage Turbine Wheels · Rolls-Royce 250-B17, 250-B17B, 250-B17C and 5 more. Effective Feb 28, 1984 - [AD 82-24-05](https://openairdocs.org/ad/82-24-05): Control Assembly and Power Turbine Governor Assembly · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 43 more. Effective Nov 26, 1982 - [AD 79-21-01 R1](https://openairdocs.org/ad/79-21-01-R1): Third Stage Turbine Wheel Blade · Rolls-Royce 250-B17, 250-B17B, 250-B17C and 3 more. Effective Jun 3, 1981 - [AD 77-15-12](https://openairdocs.org/ad/77-15-12): Power Turbine Coupling Nut · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 23 more. Effective Sep 23, 1977 - [AD 77-09-08](https://openairdocs.org/ad/77-09-08): Bleed Valve Diaphragm · Rolls-Royce 250-B17, 250-B17B, 250-C20 and 2 more. Effective Jul 18, 1977 ### Historical (superseded or no longer in force) - [AD 2012-14-11](https://openairdocs.org/ad/2012-14-11) (historical): Main Rotor Drive · Arrow Falcon Exporters OH-58A, OH-58A+, OH-58C and 6 more. Effective Aug 7, 2012 - [AD 2004-24-09](https://openairdocs.org/ad/2004-24-09) (historical): Fuel nozzle · Rolls-Royce 250-B15A, 250-B15E, 250-B15G and 40 more. Effective Jan 5, 2005 ## Information bulletins (advisory) None matched. ## NTSB investigations None matched to N602WC. ## FAA accident and incident reports None matched to N602WC. ## Service difficulty reports None filed for this aircraft. Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model. ## STCs that may be installed (OpenAirDocs) (23) Approved for this aircraft's airframe or engine model, in force first, then newest. The registry doesn't record which STCs an aircraft has; its records do. ### Approved for the airframe (San Joaquin Helicopters OH-58C) - [STC SR02249LA](https://openairdocs.org/stc/SR02249LA): Installation of replacement tail rotor blade. Van Horn Aviation LLC - [STC SR00912SE](https://openairdocs.org/stc/SR00912SE): Replacement of the original landing gear skid tubes and saddles with DART Aerospace Model D058-672-011 and 012, or D058-672-013 and 014 skid tubes and saddles. Dart Aerospace USA Inc - [STC SR00915SE](https://openairdocs.org/stc/SR00915SE): Installation of DART Heli-Access-Step, Models D058-677-011 AND-012, or D058-677-013 AND -014 fabricated. Dart Aerospace USA Inc - [STC SR00916SE](https://openairdocs.org/stc/SR00916SE): Installation of DART Model D058-678-011 Bearpaws. Dart Aerospace USA Inc - [STC SR01727SE](https://openairdocs.org/stc/SR01727SE): Fabrication of Boundary Layer Research (BLR) Dual Tail Boom Strake System. BLR Aerospace LLC - [STC SR02964CH](https://openairdocs.org/stc/SR02964CH): Install Airwolf Aerospace, LLC Tension-Torsion Strap Assemblies, P/N AA-206-011-154-105/-107. Airwolf Filter Corporation - [STC SR01286AT](https://openairdocs.org/stc/SR01286AT): Manufacture of crew vertical slide window. Bell Helicopter Textron Inc - [STC SR01287AT](https://openairdocs.org/stc/SR01287AT): Manufacture of passenger vertical slide window. Bell Helicopter Textron Inc - [STC SR01288AT](https://openairdocs.org/stc/SR01288AT): Manufacture of rubber mounted crew and passenger wedge windows. Bell Helicopter Textron Inc - [STC SR01317AT](https://openairdocs.org/stc/SR01317AT): Manufacture of folding maintenance step. Bell Helicopter Textron Inc - [STC SR01337AT](https://openairdocs.org/stc/SR01337AT): Manufacture of rubber mounted chin bubble window. Bell Helicopter Textron Inc - [STC SR01338AT](https://openairdocs.org/stc/SR01338AT): Manufacture of pre-flight step/handle. Bell Helicopter Textron Inc - [STC SR01358AT](https://openairdocs.org/stc/SR01358AT): Manufacture of maintenance step assembly. Bell Helicopter Textron Inc - [STC SR01409AT](https://openairdocs.org/stc/SR01409AT): Manufacture of replacement windshield and windows. Bell Helicopter Textron Inc - [STC SR01410AT](https://openairdocs.org/stc/SR01410AT): Manufacture of Flitestep. Bell Helicopter Textron Inc - [STC SR01446AT](https://openairdocs.org/stc/SR01446AT): Manufacture of replacement engine cowling. Bell Helicopter Textron Inc - [STC SR01447AT](https://openairdocs.org/stc/SR01447AT): Manufacture of Tailrotor Pedal Lockout. Bell Helicopter Textron Inc - [STC SR01448AT](https://openairdocs.org/stc/SR01448AT): Manufacture of Baggage Door. Bell Helicopter Textron Inc - [STC SR02031AT](https://openairdocs.org/stc/SR02031AT): Manufacture of Vibration Reduction System. Bell Helicopter Textron Inc - [STC SR00431SE](https://openairdocs.org/stc/SR00431SE): Installation of Ag-Air Systems, Inc., hydraulic accessory drive system. (206B BII, BIII) (OH-58A+ RESTRICTED CATEGORY ARROW FALCON). Kawak Aviation Technologies Inc ### Approved for the engine (Allison 250-C20C) - [STC SE5511NM](https://openairdocs.org/stc/SE5511NM): Installation of compressor discharge pressue (PC) valve. Bell Helicopter Textron Inc - [STC SE00027EN](https://openairdocs.org/stc/SE00027EN): Installation of Pratt & Whitney Engine Services Inc. Intellistart plus electronic control unit (ECU), P/N DPU-K-010 on the specified 250 engine models. Pratt & Whitney Engine Services Inc - [STC ST00037AT](https://openairdocs.org/stc/ST00037AT): Unison igniter plugs, P/N 9044400-1. Unison Industries ## Related - Other San Joaquin Helicopters OH-58C aircraft: https://openairdocs.org/model/san-joaquin-helicopters-oh-58c/aircraft.md - The Allison 250-C20C engine: https://openairdocs.org/engine/allison-250-c20c.md --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.