# N725MK: 1968 Lockheed 1329-23E - Status: Valid registration - Airframe: [Lockheed 1329-23E](https://openairdocs.org/model/lockheed-1329-23e) (registry code 5263119, 12 seats) - Engine: [Pratt & Whitney JT12A-6 6A](https://openairdocs.org/engine/pratt-whitney-jt12a-6-6a) (registry code 52042) - Data sheets: [TCDS 2A15](https://openairdocs.org/tcds/2A15) (Lockheed Martin Corporation) (OpenAirDocs) - Serial number: 5123 - Year built: 1968 - Type: Fixed wing multi engine - Engine type: Turbo-jet - Airworthiness: Standard, transport - Airworthiness date: September 30, 1968 - Certificate issued: February 20, 2007 - Expires: August 31, 2029 - Mode S code: A9B73C - Registered owner: [Ken Sale Resources Inc](https://openairdocs.org/faa-owner/KEN%20SALE%20RESOURCES%20INC) - Location: [Southlake, TX](https://openairdocs.org/faa-place/TX/Southlake) - Owner type: Corporation - Owner's area on the map: 32.9545° N, 97.1489° W: Placed by OpenAirDocs at the center of ZIP code 76092, within about 3 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based - FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=725MK - Page: https://openairdocs.org/aircraft/N725MK 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): 18 in force ### Matched by airframe (Lockheed 1329-23E) - [AD 2026-13-02](https://openairdocs.org/ad/2026-13-02): Navigation · Airbus Canada Limited Partnership 18, 49-46, 80-A and 555 more. Effective Jul 1, 2026 - [AD 2023-10-02](https://openairdocs.org/ad/2023-10-02): Indicating/Recording System, Navigation · Boeing 18, 23, 35 and 1,060 more. Effective May 26, 2023 - [AD 2008-13-26](https://openairdocs.org/ad/2008-13-26): Nose landing gear (NLG) · Lockheed Martin 1329-23A, 1329-23D, 1329-23E and 1 more. Effective Aug 12, 2008 - [AD 2005-01-02](https://openairdocs.org/ad/2005-01-02): Front spar cap assembly of the lower vertical stabilizer · Lockheed Martin 1329-23A, 1329-23D, 1329-23E and 1 more. Effective Feb 9, 2005 - [AD 2002-15-02](https://openairdocs.org/ad/2002-15-02): Compressor Wheels · British Aerospace Regional Jetstream Series 3101, 234, Mystere-Falcon 20 - C5 and 22 more. Effective Aug 28, 2002 - [AD 99-19-17](https://openairdocs.org/ad/99-19-17): AFM - Limitation Section - Ice Protection System · Lockheed Martin 1329-23A, 1329-23D, 1329-23E and 1 more. Effective Dec 27, 1999 - [AD 98-07-21](https://openairdocs.org/ad/98-07-21): Engine Tailpipe V-Band Coupling · AiResearch TFE731-3-IE engines (UNC/CFC Acquisition STC SA2326SW). Effective May 18, 1998 - [AD 96-25-12](https://openairdocs.org/ad/96-25-12): Auxiliary Power Units · BAE Systems HS 748 Series 2A, HS 748 Series 2B, 707-100 Long Body and 74 more. Effective Jan 13, 1997 - [AD 91-11-13](https://openairdocs.org/ad/91-11-13): Empennage Pivot Fittings · Lockheed Martin 1329-23A, 1329-23D, 1329-23E and 1 more. Effective Jun 24, 1991 - [AD 87-16-01](https://openairdocs.org/ad/87-16-01): Fuel Line Shrouds and Drains · GTCP30-92 or GTCP30-92C auxiliary power unit (UNC/CFC Acquisition STC SA1043WE or 2 others). Effective Aug 26, 1987 - [AD 87-07-08](https://openairdocs.org/ad/87-07-08): APU Shutoff Valve · GTCP30-92 or GTCP30-92C auxiliary power unit (UNC/CFC Acquisition STC SA1043WE or SA3297WE). Effective May 1, 1987 - [AD 84-23-01](https://openairdocs.org/ad/84-23-01): Hardware, Fasteners · Lockheed Martin 1329-23A, 1329-23D, 1329-23E and 1 more. Effective Nov 26, 1984 - [AD 75-06-05 R2](https://openairdocs.org/ad/75-06-05-R2): Fuselage Main Frames · Lockheed Martin 1329-23A, 1329-23D and 1329-23E. Effective Dec 21, 1983 - [AD 82-18-09](https://openairdocs.org/ad/82-18-09): Refueling System · Single point pressure fueling system (Rogerson ATS STC SA1851WE or 4 others). Effective Oct 4, 1982 - [AD 77-22-03](https://openairdocs.org/ad/77-22-03): Ring Segment - VHF Antenna · Lockheed Martin 1329-23A, 1329-23D, 1329-23E and 1 more. Effective Oct 28, 1977 - [AD 74-24-09](https://openairdocs.org/ad/74-24-09): Auxiliary Power Units · Airbus BAC 1-11 200 Series, BAC 1-11 400 Series, Auxiliary Power Units and 63 more. Effective Nov 19, 1975 - [AD 68-09-02](https://openairdocs.org/ad/68-09-02): Wing Skin Risers · Lockheed Martin 1329-23A, 1329-23D and 1329-23E. Effective Nov 19, 1968 - [AD 68-08-07](https://openairdocs.org/ad/68-08-07): Airspeed and Altimeter Systems · Lockheed Martin 1329-23A, 1329-23D and 1329-23E. Effective Apr 19, 1968 ### Matched by engine (Pratt & Whitney JT12A-6 6A) None in force. ## Information bulletins (advisory) None matched. ## NTSB investigations None matched to N725MK. ## FAA accident and incident reports None matched to N725MK. ## 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) (234, first 50) 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 (Lockheed 1329-23E) - [STC SA2622NM](https://openairdocs.org/stc/SA2622NM): Installation of Precise Flight Pulselite Control Unit in landing/taxi system. (767-200 B17) (DHC-8 101). Precise Flight Inc - [STC ST00155DE-D](https://openairdocs.org/stc/ST00155DE-D): Installation of TCAS 791 TCAS I System. Acron Aviation Inc - [STC ST03424CH](https://openairdocs.org/stc/ST03424CH): Certification of Automatic Dependent Surveillance - Broadcast (ADS-B) Out System with Rockwell Collins TDR-94/-94D Transponders. CMD Flight Solutions LLC - [STC ST04575AT](https://openairdocs.org/stc/ST04575AT): Installation of the Rockwell Collins ALT-1000+/ -4000+ with 5G Filtering. Chippewa Aerospace Inc - [STC SA4018WE](https://openairdocs.org/stc/SA4018WE): Installation of on-board air stairs. Dow Aero Logistics LLC. Lists 1329 Series - [STC SA1664WE](https://openairdocs.org/stc/SA1664WE): Installation of Sperry SP-40C auto flight control system and SPI-73B Sperry instrumentation system. Honeywell International Inc - [STC ST00347BO](https://openairdocs.org/stc/ST00347BO): Modification to upgrade a BendixKing CAS 67A TCAS II system to CAS 67B TCAS II Change 7.1. Pro Star Aviation, LLC - [STC SA2-1574](https://openairdocs.org/stc/SA2-1574): Change SP-40 Autopilot heading and radio control data from the copilot's R-4A Course Indicator and #2 VHF Navigation system to the pilot's R-4A Course Indicator and #1 VHF Navigation system. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA535SW](https://openairdocs.org/stc/SA535SW): Relocation and use of miniature switches in fuel flow system. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA548SW](https://openairdocs.org/stc/SA548SW): Installation of a Flight Recorder System. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA602SW](https://openairdocs.org/stc/SA602SW): Installation of a hinged instrument panel in a Lockheed Model 1329 aircraft. Associated Air Center, Inc. - c/o CT Corporation System. Lists 1329 Series - [STC SA762SW](https://openairdocs.org/stc/SA762SW): Smith servo altimeter system. Associated Air Center, Inc. - c/o CT Corporation System. Lists 1329 Series - [STC SA769SW](https://openairdocs.org/stc/SA769SW): Collins 329P-1D peripheral commander Indicating System. Associated Air Center, Inc. - c/o CT Corporation System. Lists 1329 Series - [STC SA1087SW](https://openairdocs.org/stc/SA1087SW): Installation of Butler VAC area navigation system. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA345SW](https://openairdocs.org/stc/SA345SW): Installation of Bendix Doppler radar navigation system. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA536SW](https://openairdocs.org/stc/SA536SW): Installation of a Litton low range radio altimeter system. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA561SW](https://openairdocs.org/stc/SA561SW): Modification of glare shield for quick removal. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA783SW](https://openairdocs.org/stc/SA783SW): Installation of Bar extension equipment shelf. Associated Air Center, Inc. - c/o CT Corporation System. Lists 1329 Series - [STC SA827SW](https://openairdocs.org/stc/SA827SW): Installation of a Fairchild Model 5424-502 flight data recorder. Associated Air Center, Inc. - c/o CT Corporation System. Lists 1329 Series - [STC SA828SW](https://openairdocs.org/stc/SA828SW): Installation of Fairchild A100 cockpit voice recorder. Associated Air Center, Inc. - c/o CT Corporation System. Lists 1329 Series - [STC SA844SW](https://openairdocs.org/stc/SA844SW): Installation of Consolidated Electrodynamic Corporation Advanced Airborne Vibration Monitor System. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA876SW](https://openairdocs.org/stc/SA876SW): Bulkhead modification. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA877SW](https://openairdocs.org/stc/SA877SW): Pedestal modification. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA879SW](https://openairdocs.org/stc/SA879SW): Hinged instrument panel and modification to control column. Associated Air Center, Inc. - c/o CT Corporation System. Lists 1329 Series - [STC SA883SW](https://openairdocs.org/stc/SA883SW): Mounting bracket antenna tuner. Associated Air Center, Inc. - c/o CT Corporation System. Lists 1329 Series - [STC SA884SW](https://openairdocs.org/stc/SA884SW): Hoskins power supply support. Associated Air Center, Inc. - c/o CT Corporation System. Lists 1329 Series - [STC SA885SW](https://openairdocs.org/stc/SA885SW): Bulkhead coax fitting and VHF or FM antenna. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA887SW](https://openairdocs.org/stc/SA887SW): Installation of "L" Band Antenna. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA900SW](https://openairdocs.org/stc/SA900SW): Installation of Skyphone antenna. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA902SW](https://openairdocs.org/stc/SA902SW): Installation of Howell Autotemp Indicators. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA904SW](https://openairdocs.org/stc/SA904SW): Installation of Mach Airspeed Warning Switch. Associated Air Center, Inc. - c/o CT Corporation System - [STC SA1525SW](https://openairdocs.org/stc/SA1525SW): Installation of TRAMM BT1 600 nickel cadmium battery temperature indicator. FoxCart GSE, LLC - [STC SA374CE](https://openairdocs.org/stc/SA374CE): Installation of Hoskins Twilighter Mk III Supplemental Lighting System in accordance with FAA sealed Hoskins Top Drawing No. 10-0031. BF Goodrich Aerospace - [STC SA996EA](https://openairdocs.org/stc/SA996EA): Installation of Shaw Aero fuel filler cap P/Ns 457-2, -266, -370, 431, -9R, -125, -1251. Parker Hannifin Fluid Systems Division - [STC ST01095CH-D](https://openairdocs.org/stc/ST01095CH-D): Installation of an Allied Signal CAS-67A Traffic Alert and Collision Avoidance System (TCAS II). Installed per ElectroSonics Drawing ES1329-205075-01, Rev. 2, dated 09-20-00 or later FAA approved revision. Standard Aero - [STC ST00523WI-D](https://openairdocs.org/stc/ST00523WI-D): Installation of an AlliedSignal Avionics, Inc., GNS-XIs Flight Management System (Dual). Duncan Aviation Inc - [STC ST00970WI-D](https://openairdocs.org/stc/ST00970WI-D): Installation of a Collins AHS-3000A Attitude Heading Reference System (AHRS). Duncan Aviation Inc - [STC ST01059WI-D](https://openairdocs.org/stc/ST01059WI-D): Installation of Honeywell MK VII Enhanced Ground Proximity Warning System (EGPWS). Duncan Aviation Inc - [STC ST01312WI](https://openairdocs.org/stc/ST01312WI): Vertical Separation Minimum (RVSM) non-group (individual) airworthiness approval of specific Lockheed Martin Model 1329-23 aircraft. Kohlman Systems Research Inc - [STC ST02038CH-D](https://openairdocs.org/stc/ST02038CH-D): Installation of Honeywell N1 Digital Electronic Engine Controls (DEEC). Standard Aero - [STC SA918SW](https://openairdocs.org/stc/SA918SW): Installation of Teledyne avionics normalized angle of attack indicating system. Aerosonic Corporation - [STC SA2751SW](https://openairdocs.org/stc/SA2751SW): Installation of Tracor Model 7640A Omega navigation system. Hawker Beechcraft Services Inc - [STC ST01740SE](https://openairdocs.org/stc/ST01740SE): ONE-ONLY: Non-group approval for Reduced Vertical Separation Minimum, S/N 5150. AeroMech Incorporated - [STC ST00844WI-D](https://openairdocs.org/stc/ST00844WI-D): Modification of Collins TCAS II or TCAS-94 (TCAS II) system installation with Collins TTR-920 Change 7.0 Receiver Transmitter to a Collins TCAS II or TCAS-94 OTCAS II) system installation with Collins TTR-921 or Collins TTR-4000 Change 7.0 TCAS Receiver Transmitter. Rockwell Collins Inc - [STC ST01667SE](https://openairdocs.org/stc/ST01667SE): Descriptive data pertaining to this design change are considered inadequate for duplication on other products. This approval is limited to Lockheed Model 1329-23E, Serial Number 5099 only. Non-group approval for Reduced Vertical Separation Minimum. AeroMech Incorporated - [STC ST01312WI-D](https://openairdocs.org/stc/ST01312WI-D): Reduced Vertical Separation Minimum (RVSM) non-group (individual) airworthiness approval of specific Lockheed Martin Model 1329-23 aircraft in accordance with Kohlman Systems Research (KSR) Master Drawing List Jetstar 1329-23, Drawing No. MDL 1009, Rev. OR, dated January 06, 2005, or later FAA approved revision. Kohlman Systems Research Inc - [STC ST00914WI-D](https://openairdocs.org/stc/ST00914WI-D): Installation of Dual IS&S Air Data/Altimeter System along with a two-inch standby pneumatic altimeter. Duncan Aviation Inc - [STC ST02037CH](https://openairdocs.org/stc/ST02037CH): Installation of Michelin main landing gear tires. World Harvest Church - [STC SA61NE](https://openairdocs.org/stc/SA61NE): Installation of Garrett AiResearch GTCP36-100(H) auxiliary power unit. PATS Aircraft LLC - [STC SA880EA](https://openairdocs.org/stc/SA880EA): Installation of Solar T-62T-39 gas turbine auxiliary power unit. PATS Aircraft LLC All 234: https://openairdocs.org/aircraft/N725MK/stcs.md ## Related - Other Lockheed 1329-23E aircraft: https://openairdocs.org/model/lockheed-1329-23e/aircraft.md - The Pratt & Whitney JT12A-6 6A engine: https://openairdocs.org/engine/pratt-whitney-jt12a-6-6a.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.