# N21723: 1999 Boeing 737-724

- Status: Valid registration
- Airframe: [Boeing 737-724](https://openairdocs.org/model/boeing-737-724) (registry code 13844BY, 149 seats)
- Engine: [CFM International CFM56 series](https://openairdocs.org/engine/cfm-international-cfm56-series) (registry code 13802)
- Data sheets: [TCDS A16WE](https://openairdocs.org/tcds/A16WE) (The Boeing Company) (OpenAirDocs)
- Serial number: 28790
- Year built: 1999
- Type: Fixed wing multi engine
- Engine type: Turbo-fan
- Airworthiness: Standard, transport
- Airworthiness date: April 21, 1999
- Certificate issued: April 23, 1999
- Expires: January 31, 2030
- Mode S code: A1D63D
- Registered owner: [United Airlines Inc](https://openairdocs.org/faa-owner/UNITED%20AIRLINES%20INC)
- Location: [Chicago, IL](https://openairdocs.org/faa-place/IL/Chicago)
- Owner type: Corporation
- Owner's area on the map: 41.8813° N, 87.6375° W: Placed by OpenAirDocs at the center of ZIP code 60606, within about a mile (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=21723
- Page: https://openairdocs.org/aircraft/N21723

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. The registry lists only the engine series, so ADs for every CFM International CFM56 model are included.

## ADs that may apply (OpenAirDocs): 378 in force

### Matched by airframe (Boeing 737-724)

- [AD 2026-20-14](https://openairdocs.org/ad/2026-20-14): Stabilizers · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Nov 23, 2026
- [AD 2026-20-13](https://openairdocs.org/ad/2026-20-13): Equipment/furnishings · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Nov 23, 2026
- [AD 2026-13-13](https://openairdocs.org/ad/2026-13-13): Navigation · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 9 more. Effective Jul 1, 2026
- [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 2025-25-04](https://openairdocs.org/ad/2025-25-04): Equipment/furnishings · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 6 more. Effective Jan 16, 2026
- [AD 2025-24-02](https://openairdocs.org/ad/2025-24-02): Landing gear · Boeing 737-700 Series, 737-800 Series, 737-900 Series and 1 more. Effective Dec 10, 2025
- [AD 2025-19-12](https://openairdocs.org/ad/2025-19-12): Landing Gear · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Nov 6, 2025
- [AD 2025-15-01](https://openairdocs.org/ad/2025-15-01): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Aug 25, 2025
- [AD 2025-07-03](https://openairdocs.org/ad/2025-07-03): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective May 13, 2025
- [AD 2025-04-03](https://openairdocs.org/ad/2025-04-03): Exhaust · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Apr 8, 2025
- [AD 2025-04-02](https://openairdocs.org/ad/2025-04-02): Powerplant · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Apr 8, 2025
- [AD 2025-04-01](https://openairdocs.org/ad/2025-04-01): Powerplant · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Apr 8, 2025
- [AD 2025-02-07](https://openairdocs.org/ad/2025-02-07): Navigation · Modification of Rockwell Collins, Inc. Multi-Mode Receiver (STC ST01883WI or 4 others). Effective Mar 17, 2025
- [AD 2024-18-07](https://openairdocs.org/ad/2024-18-07): Equipment/Furnishing · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Nov 12, 2024
- [AD 2024-16-10](https://openairdocs.org/ad/2024-16-10): Instruments · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Oct 28, 2024
- [AD 2024-13-02](https://openairdocs.org/ad/2024-13-02): Oxygen · Boeing 737-8, 737-9, 737-8200 and 3 more. Effective Jul 25, 2024
- [AD 2024-06-01](https://openairdocs.org/ad/2024-06-01): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective May 22, 2024
- [AD 2024-01-06](https://openairdocs.org/ad/2024-01-06): Fuselage · Boeing 737-600 Series, 737-700 Series and 737-800 Series. Effective Mar 7, 2024
- [AD 2023-13-05](https://openairdocs.org/ad/2023-13-05): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Oct 27, 2023
- [AD 2023-13-12](https://openairdocs.org/ad/2023-13-12): Oxygen · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 17 more. Effective Sep 5, 2023
- [AD 2023-12-13](https://openairdocs.org/ad/2023-12-13): Navigation · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 9 more. Effective Jun 21, 2023
- [AD 2023-06-15](https://openairdocs.org/ad/2023-06-15): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-800 Series and 2 more. Effective May 30, 2023
- [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 2023-04-17](https://openairdocs.org/ad/2023-04-17): Fuel · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 5 more. Effective May 1, 2023
- [AD 2022-24-09](https://openairdocs.org/ad/2022-24-09): Air conditioning · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 12 more. Effective Jan 26, 2023
- [AD 2022-18-13](https://openairdocs.org/ad/2022-18-13): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Oct 31, 2022
- [AD 2022-13-18](https://openairdocs.org/ad/2022-13-18): Oxygen · Boeing 737-700 Series, 737-800 Series, 747-8 Series and 3 more. Effective Sep 15, 2022
- [AD 2022-15-08](https://openairdocs.org/ad/2022-15-08): Information systems · Airbus A318-111, A318-112, A319-111 and 49 more. Effective Aug 12, 2022
- [AD 2022-11-13](https://openairdocs.org/ad/2022-11-13): Fuselage · Boeing 737-700 Series, 737-800 Series and 737-900ER Series. Effective Aug 3, 2022
- [AD 2022-06-06](https://openairdocs.org/ad/2022-06-06): Flight controls · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 5 more. Effective Jun 16, 2022
- [AD 2021-26-17](https://openairdocs.org/ad/2021-26-17): Equipment/furnishings · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Feb 15, 2022
- [AD 2021-18-17](https://openairdocs.org/ad/2021-18-17): Auto flight · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Dec 20, 2021
- [AD 2021-21-09](https://openairdocs.org/ad/2021-21-09): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Dec 13, 2021
- [AD 2021-11-24](https://openairdocs.org/ad/2021-11-24): Fuel · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Jul 20, 2021
- [AD 2021-08-04](https://openairdocs.org/ad/2021-08-04): Oxygen · Boeing 737-200 Series, 737-300 Series, 737-400 Series and 23 more. Effective May 26, 2021
- [AD 2021-02-14](https://openairdocs.org/ad/2021-02-14): Fuel · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Mar 30, 2021
- [AD 2021-02-13](https://openairdocs.org/ad/2021-02-13): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Mar 30, 2021
- [AD 2021-01-04](https://openairdocs.org/ad/2021-01-04): Doors · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 5 more. Effective Mar 29, 2021
- [AD 2021-01-07](https://openairdocs.org/ad/2021-01-07): Air Distribution System · Boeing 737-700 Series. Effective Mar 9, 2021
- [AD 2020-21-02](https://openairdocs.org/ad/2020-21-02): Fire protection · Airbus Canada Limited Partnership BD-500-1A10, BD-500-1A11, A330-201 and 45 more. Effective Nov 19, 2020
- [AD 2020-18-13](https://openairdocs.org/ad/2020-18-13): Fuel · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Oct 29, 2020
- [AD 2020-16-51](https://openairdocs.org/ad/2020-16-51): Pneumatic · Boeing 737-300 Series, 737-400 Series, 737-500 Series and 6 more. Effective Aug 26, 2020
- [AD 2020-03-10](https://openairdocs.org/ad/2020-03-10): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 5 more. Effective Mar 27, 2020
- [AD 2019-25-55](https://openairdocs.org/ad/2019-25-55): Equipment/ Furnishings · Boeing 737-300 Series, 737-400 Series and 737-700 Series with STC ST01566LA or 2 others. Effective Jan 21, 2020
- [AD 2019-19-10](https://openairdocs.org/ad/2019-19-10): Fuel · Boeing 737-300 Series, 737-400 Series, 737-500 Series and 21 more. Effective Jan 16, 2020
- [AD 2019-18-03](https://openairdocs.org/ad/2019-18-03): Exhaust · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 5 more. Effective Oct 3, 2019
- [AD 2019-14-02](https://openairdocs.org/ad/2019-14-02): Hydraulic power · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 11 more. Effective Aug 27, 2019
- [AD 2019-11-06](https://openairdocs.org/ad/2019-11-06): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Jul 17, 2019
- [AD 2019-03-07](https://openairdocs.org/ad/2019-03-07): Wings · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Mar 29, 2019
- [AD 2019-01-03](https://openairdocs.org/ad/2019-01-03): Landing Gear · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Mar 19, 2019

### Matched by engine (CFM International CFM56 series)

- [AD 2023-05-05](https://openairdocs.org/ad/2023-05-05): Turbine Engine Compressor Section · CFM International CFM56-5B1, CFM56-5B1/2P, CFM56-5B1/3 and 98 more. Effective May 10, 2023
- [AD 2022-02-03](https://openairdocs.org/ad/2022-02-03): Turbine Engine Accessory Drive · CFM International CFM56-3, CFM56-3B, CFM56-3C and 34 more. Effective Mar 22, 2022
- [AD 2021-16-08](https://openairdocs.org/ad/2021-16-08): Turbine Section · CFM International CFM56-5B1, CFM56-5B1/2P, CFM56-5B1/P and 55 more. Effective Sep 28, 2021
- [AD 2018-26-01](https://openairdocs.org/ad/2018-26-01): Turbine Engine Compressor Section · CFM International CFM56-7B20, CFM56-7B20/2, CFM56-7B20/3 and 46 more. Effective Jan 10, 2019
- [AD 2018-09-51](https://openairdocs.org/ad/2018-09-51): Engine · CFM International CFM56-7B20, CFM56-7B20/2, CFM56-7B20/3 and 46 more. Effective Jun 7, 2018
- [AD 2017-14-08](https://openairdocs.org/ad/2017-14-08): Turbine Engine Compressor Section · CFM International CFM56-3, CFM56-3B and CFM56-3C. Effective Aug 18, 2017
- [AD 2017-05-09](https://openairdocs.org/ad/2017-05-09): Accessory Gearboxes · CFM International CFM56-5B1, CFM56-5B1/2P, CFM56-5B1/3 and 33 more. Effective Apr 13, 2017
- [AD 2016-14-10](https://openairdocs.org/ad/2016-14-10): High-pressure turbine (HPT) disks · CFM International CFM56-3, CFM56-3B and CFM56-3C with STC SE00034EN. Effective Aug 9, 2016
- [AD 2016-02-04](https://openairdocs.org/ad/2016-02-04): Turbine rear frames (TRFs) · CFM International CFM56-5B1, CFM56-5B1/2P, CFM56-5B1/3 and 33 more. Effective Mar 1, 2016
- [AD 2015-18-04](https://openairdocs.org/ad/2015-18-04): 73-tooth gearshaft located in the engine accessory gearbox (AGB) · CFM International CFM56-3, CFM56-7B20, CFM56-7B20/2 and 47 more. Effective Oct 20, 2015
- [AD 2015-04-02](https://openairdocs.org/ad/2015-04-02): Dual engine thrust instability event · CFM International CFM56-7B20, CFM56-7B20/2, CFM56-7B20/3 and 46 more. Effective Mar 31, 2015
- [AD 2013-14-06](https://openairdocs.org/ad/2013-14-06): Hydro-mechanical unit (HMU) fuel control · CFM International CFM56-5, CFM56-5B1, CFM56-5B1/2P and 34 more. Effective Sep 3, 2013
- [AD 2012-02-03](https://openairdocs.org/ad/2012-02-03): Engine · CFM International CFM56-5B1/3, CFM56-5B2/3, CFM56-5B3/3 and 8 more. Effective Mar 15, 2012
- [AD 2010-13-09](https://openairdocs.org/ad/2010-13-09): Stage 3 low-pressure turbine (LPT) · CFM International CFM56-5, CFM56-5-A1/F, CFM56-5A4 and 88 more. Effective Jul 26, 2010
- [AD 2010-12-03](https://openairdocs.org/ad/2010-12-03): Fan blades · CFM International CFM56-3 and CFM56-3B. Effective Jul 13, 2010
- [AD 2010-09-14](https://openairdocs.org/ad/2010-09-14): Exhaust gas temperature (EGT) · CFM International CFM56-5B1/2P, CFM56-5B1/P, CFM56-5B2/2P and 16 more. Effective Jun 8, 2010
- [AD 2010-01-05](https://openairdocs.org/ad/2010-01-05): LP turbine rear frames · CFM International CFM56-7B20, CFM56-7B20/2, CFM56-7B20/3 and 25 more. Effective Feb 18, 2010
- [AD 2009-18-01](https://openairdocs.org/ad/2009-18-01): LP turbine rear frames · CFM International CFM56-5B1/3, CFM56-5B1/P, CFM56-5B2/3 and 19 more. Effective Oct 1, 2009
- [AD 2009-11-02](https://openairdocs.org/ad/2009-11-02): HPC 4-9 spools · CFM International CFM56-2, CFM56-2A, CFM56-2B and 109 more. Effective Jun 23, 2009
- [AD 2008-03-09](https://openairdocs.org/ad/2008-03-09): Low pressure turbine rear frames (TRFs) · CFM International CFM56-7B18, CFM56-7B20, CFM56-7B22 and 10 more. Effective Mar 10, 2008
- [AD 2007-24-04](https://openairdocs.org/ad/2007-24-04): Low pressure turbine (LPT) · CFM International CFM56-5C4/1. Effective Dec 6, 2007
- [AD 2007-03-15](https://openairdocs.org/ad/2007-03-15): Exhaust gas temperature (EGT) harness · CFM International CFM56-5, CFM56-5B1, CFM56-5B1/2P and 34 more. Effective Mar 19, 2007
- [AD 2006-26-01](https://openairdocs.org/ad/2006-26-01): Fuel filters · CFM International CFM56-2, CFM56-2A, CFM56-2B and 93 more. Effective Jan 3, 2007
- [AD 2005-10-05](https://openairdocs.org/ad/2005-10-05): Air turbine starters · CFM International CFM56-5, CFM56-5B1, CFM56-5B1/2P and 50 more. Effective Jun 14, 2005
- [AD 97-09-02 R3](https://openairdocs.org/ad/97-09-02-R3): High pressure turbine rotor (HPTR) front shafts · CFM International CFM56-5C2, CFM56-5C3/G and CFM56-5C4. Effective Oct 14, 2004
- [AD 2004-10-13](https://openairdocs.org/ad/2004-10-13): Service main fuel pumps · CFM International CFM56-3, CFM56-5, CFM56-5-A1/F and 4 more. Effective Jun 24, 2004
- [AD 2002-22-12](https://openairdocs.org/ad/2002-22-12): Titeflex hoses · BAE Systems ATP, Avro 146-RJ100A, Avro 146-RJ70A and 122 more. Effective Dec 13, 2002
- [AD 2002-16-18](https://openairdocs.org/ad/2002-16-18): Low pressure turbine (LPT) nozzle segments · CFM International CFM56-5B1, CFM56-5B1/2P, CFM56-5B1/P and 33 more. Effective Sep 18, 2002
- [AD 2002-13-03](https://openairdocs.org/ad/2002-13-03): Turbofan Engines · CFM International CFM56-2, CFM56-2A, CFM56-2B and 55 more. Effective Aug 1, 2002
- [AD 2002-02-13](https://openairdocs.org/ad/2002-02-13): Magnetic Drain Plug · CFM International CFM56-5, CFM56-5-A1/F, CFM56-5A4 and 33 more. Effective Mar 21, 2002
- [AD 2001-11-05](https://openairdocs.org/ad/2001-11-05): No. 4 Bearings · CFM International CFM56-2, CFM56-2B, CFM56-3 and 45 more. Effective Jun 11, 2001
- [AD 2001-09-17](https://openairdocs.org/ad/2001-09-17): Fuel Manifold and CJ9L Harness · CFM International CFM56-5C2, CFM56-5C2/4, CFM56-5C2/F and 13 more. Effective May 14, 2001
- [AD 2001-04-06](https://openairdocs.org/ad/2001-04-06): Fan Disk · CFM International CFM56-3, CFM56-3B and CFM56-3C. Effective Apr 4, 2001
- [AD 2001-02-12](https://openairdocs.org/ad/2001-02-12): On-Wing Torque Inspection · CFM International CFM56-7B20, CFM56-7B20/2, CFM56-7B22 and 11 more. Effective Feb 14, 2001
- [AD 2000-15-01](https://openairdocs.org/ad/2000-15-01): Fuel Leakage · CFM International CFM56-2, CFM56-2A, CFM56-2B and 39 more. Effective Oct 2, 2000
- [AD 2000-05-22](https://openairdocs.org/ad/2000-05-22): CFM International CFM56-2, CFM56-2A, CFM56-2B and 3 more. Effective May 2, 2000
- [AD 99-06-16](https://openairdocs.org/ad/99-06-16): High Pressure Turbine Rotor (HPTR) Front Air Seal · CFM International CFM56-5, CFM56-5-A1/F, CFM56-5A4 and 3 more. Effective Apr 21, 1999
- [AD 98-21-23](https://openairdocs.org/ad/98-21-23): Electronic Engine Control · CFM International CFM56-7B20, CFM56-7B20/2, CFM56-7B22 and 10 more. Effective Nov 2, 1998
- [AD 98-19-20](https://openairdocs.org/ad/98-19-20): Hydromechanical Unit · CFM International CFM56-7B20, CFM56-7B20/2, CFM56-7B22 and 7 more. Effective Oct 7, 1998
- [AD 98-14-51](https://openairdocs.org/ad/98-14-51): Accessory Gearbox · CFM International CFM56-7B20, CFM56-7B20/2, CFM56-7B22 and 10 more. Effective Oct 1, 1998
- [AD 98-19-10](https://openairdocs.org/ad/98-19-10): Accessory Gearbox · CFM International CFM56-3, CFM56-3B and CFM56-3C. Effective Sep 28, 1998
- [AD 98-12-32](https://openairdocs.org/ad/98-12-32): High Pressure Turbine Rotor Disks · CFM International CFM56-2, CFM56-2A, CFM56-2B and 3 more. Effective Jul 20, 1998
- [AD 98-10-11](https://openairdocs.org/ad/98-10-11): Accessory Gearbox · CFM International CFM56-3, CFM56-3B, CFM56-3C and 31 more. Effective Jun 3, 1998
- [AD 98-07-02](https://openairdocs.org/ad/98-07-02): Air/oil Seal · CFM International CFM56-3, CFM56-3B and CFM56-3C. Effective Mar 30, 1998
- [AD 98-02-04](https://openairdocs.org/ad/98-02-04): Low Pressure Turbine Case · CFM International CFM56-5B1/2P, CFM56-5B2/2P, CFM56-5B3/2P and 1 more. Effective Mar 23, 1998
- [AD 89-23-06 R1](https://openairdocs.org/ad/89-23-06-R1): Magnetic Chip Detector · CFM International CFM56-2, CFM56-2A, CFM56-3 and 8 more. Effective Jan 28, 1998
- [AD 97-08-01](https://openairdocs.org/ad/97-08-01): Fan Disks · CFM International CFM56-3, CFM56-3B and CFM56-3C. Effective Jun 23, 1997
- [AD 97-06-01](https://openairdocs.org/ad/97-06-01): High Pressure Compressor Rotor (HPCR) Stage 1-2 Spool · CFM International CFM56-5, CFM56-5B1, CFM56-5B1/2P and 28 more. Effective Jun 3, 1997
- [AD 97-05-13](https://openairdocs.org/ad/97-05-13): Air Turbine Engine Starter · CFM International CFM56-5, CFM56-5-A1/F, CFM56-5A4 and 3 more. Effective Jun 3, 1997
- [AD 96-25-11](https://openairdocs.org/ad/96-25-11): Redesigned Fan Blades · CFM International CFM56-3B and CFM56-3C. Effective Jan 29, 1997

### Historical (superseded or no longer in force)

- [AD 2023-09-04](https://openairdocs.org/ad/2023-09-04) (historical): Equipment/furnishings · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 5 more. Effective Jun 29, 2023
- [AD 2022-05-04](https://openairdocs.org/ad/2022-05-04) (historical): Navigation · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 9 more. Effective Feb 24, 2022
- [AD 2021-14-20](https://openairdocs.org/ad/2021-14-20) (historical): Cabin Altitude Pressure Switches · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 12 more. Effective Jul 20, 2021
- [AD 2021-09-06](https://openairdocs.org/ad/2021-09-06) (historical): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Jun 8, 2021
- [AD 2020-03-20](https://openairdocs.org/ad/2020-03-20) (historical): Navigation · Modification of Rockwell Collins, Inc. Multi-Mode Receiver (STC ST01883WI or 4 others). Effective Feb 18, 2020
- [AD 2019-25-17](https://openairdocs.org/ad/2019-25-17) (historical): Indicating/ recording system · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Dec 27, 2019
- [AD 2019-20-03](https://openairdocs.org/ad/2019-20-03) (historical): Information systems · Airbus A340-312, A340-313, A318-111 and 48 more. Effective Nov 19, 2019
- [AD 2019-22-10](https://openairdocs.org/ad/2019-22-10) (historical): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Nov 13, 2019
- [AD 2019-20-02](https://openairdocs.org/ad/2019-20-02) (historical): Fuselage · Boeing Airplane Company, Wichita Division 75 (Army PT-13), 737-600 Series, 737-700 Series and 4 more. Effective Oct 3, 2019
- [AD 2019-03-26](https://openairdocs.org/ad/2019-03-26) (historical): Equipment/furnishings · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Apr 8, 2019
- [AD 2017-16-05](https://openairdocs.org/ad/2017-16-05) (historical): Wings · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Sep 22, 2017
- [AD 2017-14-13](https://openairdocs.org/ad/2017-14-13) (historical): Equipment and Furnishings · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Aug 23, 2017
- [AD 2016-18-01](https://openairdocs.org/ad/2016-18-01) (historical): Landing Gear · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Oct 5, 2016
- [AD 2016-13-16](https://openairdocs.org/ad/2016-13-16) (historical): Stabilizers · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Aug 12, 2016
- [AD 2015-19-03](https://openairdocs.org/ad/2015-19-03) (historical): Fuel Selector/Shutoff Valve · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Oct 21, 2015
- [AD 2015-16-01](https://openairdocs.org/ad/2015-16-01) (historical): Air Conditioning · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 9 more. Effective Sep 15, 2015
- [AD 2013-26-08](https://openairdocs.org/ad/2013-26-08) (historical): Ice and Rain Protection · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Feb 10, 2014
- [AD 2013-24-13](https://openairdocs.org/ad/2013-24-13) (historical): Fuselage · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 8 more. Effective Jan 7, 2014
- [AD 2013-19-04](https://openairdocs.org/ad/2013-19-04) (historical): Fuselage · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Nov 4, 2013
- [AD 2013-18-09](https://openairdocs.org/ad/2013-18-09) (historical): Communications · Airbus A300 B2-1A, A300 B2-1C, A300 B2-203 and 137 more. Effective Oct 3, 2013
- [AD 2013-07-09](https://openairdocs.org/ad/2013-07-09) (historical): Oxygen · Boeing 737-700 Series, 737-700C Series, 737-800 Series and 4 more. Effective May 20, 2013
- [AD 2013-07-07](https://openairdocs.org/ad/2013-07-07) (historical): Stabilizers · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective May 20, 2013
- [AD 2012-21-08](https://openairdocs.org/ad/2012-21-08) (historical): Auto Flight · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Nov 27, 2012
- [AD 2012-19-11](https://openairdocs.org/ad/2012-19-11) (historical): Air Conditioning · Boeing 737-100 Series, 737-200 Series, 737-200C Series and 9 more. Effective Nov 7, 2012
- [AD 2010-17-05](https://openairdocs.org/ad/2010-17-05) (historical): Fuel system · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Sep 22, 2010
- [AD 2010-17-19](https://openairdocs.org/ad/2010-17-19) (historical): Flight controls · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Sep 9, 2010
- [AD 2010-09-05](https://openairdocs.org/ad/2010-09-05) (historical): Flight controls · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Apr 29, 2010
- [AD 2010-06-51](https://openairdocs.org/ad/2010-06-51) (historical): Flight controls · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Apr 7, 2010
- [AD 2009-24-07](https://openairdocs.org/ad/2009-24-07) (historical): Landing gear · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 1 more. Effective Jan 4, 2010
- [AD 2009-21-10](https://openairdocs.org/ad/2009-21-10) (historical): Oxygen · Airbus A300, Model B4-605R, A300, Model B4-620, A300, Model B4-622 and 138 more. Effective Dec 17, 2009
- [AD 2009-01-02](https://openairdocs.org/ad/2009-01-02) (historical): Air conditioning (A/C) outlet · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Feb 27, 2009
- [AD 2008-12-04](https://openairdocs.org/ad/2008-12-04) (historical): Fuselage skin · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Jul 16, 2008
- [AD 2008-10-10](https://openairdocs.org/ad/2008-10-10) (historical): New limitations for fuel tank systems · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Jun 12, 2008
- [AD 2008-08-24](https://openairdocs.org/ad/2008-08-24) (historical): Drain tube assemblies · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective May 27, 2008
- [AD 2007-18-52](https://openairdocs.org/ad/2007-18-52) (historical): Main slat track downstop assemblies · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Sep 26, 2007
- [AD 2007-18-51](https://openairdocs.org/ad/2007-18-51) (historical): Main slat track downstop assembly · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 3 more. Effective Aug 25, 2007
- [AD 2006-10-17](https://openairdocs.org/ad/2006-10-17) (historical): Compass bracket assembly · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Jun 22, 2006
- [AD 2005-24-03](https://openairdocs.org/ad/2005-24-03) (historical): Nacelle support fittings and the lower wing skin panels · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 1 more. Effective Dec 28, 2005
- [AD 2005-25-03](https://openairdocs.org/ad/2005-25-03) (historical): Point "D" splice fitting · Boeing 737-700 Series, 737-700C Series and 737-800 Series. Effective Dec 21, 2005
- [AD 2005-12-05](https://openairdocs.org/ad/2005-12-05) (historical): Flight deck door · Reinforced cockpit door (Safran Cabin STC ST01335LA or 2 others). Effective Jul 19, 2005
- [AD 2005-07-20](https://openairdocs.org/ad/2005-07-20) (historical): Flight control computers · Boeing 737-600 Series, 737-700 Series, 737-800 Series and 1 more. Effective May 12, 2005
- [AD 2005-05-18](https://openairdocs.org/ad/2005-05-18) (historical): Webs of the aft pressure bulkhead · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Apr 18, 2005
- [AD 2003-14-04](https://openairdocs.org/ad/2003-14-04) (historical): Flight Deck Door Pressure Relief Latch Assemblies · Boeing 737-200 Series, 737-300 Series, 737-400 Series and 14 more. Effective Jul 25, 2003
- [AD 2003-03-01](https://openairdocs.org/ad/2003-03-01) (historical): Aft Engine Mount · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Feb 13, 2003
- [AD 2002-18-52](https://openairdocs.org/ad/2002-18-52) (historical): Fuel Pumps · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 4 more
- [AD 2002-16-03](https://openairdocs.org/ad/2002-16-03) (historical): Main landing gear (MLG) · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 2 more. Effective Aug 27, 2002
- [AD 2001-06-08](https://openairdocs.org/ad/2001-06-08) (historical): Elevator Hinge Plates · Boeing 737-600 Series, 737-700 Series and 737-800 Series. Effective Apr 9, 2001
- [AD 2001-04-08](https://openairdocs.org/ad/2001-04-08) (historical): Elevator Tab Assembly · Boeing 737-600 Series, 737-700 Series, 737-700C Series and 1 more. Effective Mar 20, 2001
- [AD 99-08-03](https://openairdocs.org/ad/99-08-03) (historical): Power Feeder Terminals · Boeing 737-600 Series, 737-700 Series and 737-800 Series. Effective Apr 19, 1999
- [AD 99-04-11](https://openairdocs.org/ad/99-04-11) (historical): Aft Strut Insulation Blankets · Boeing 737-600 Series, 737-700 Series and 737-800 Series. Effective Mar 18, 1999

All 447: https://openairdocs.org/aircraft/N21723/ads.md

## Information bulletins (advisory) (22 in force)

- [SAIB 2026-17](https://openairdocs.org/saib/2026-17): VNAV Approach Disconnect Following Missed Approach, Anomaly on Airplanes with FMC U14.0/14.1. Issued Oct 3, 2026
- [SAIB 2025-08](https://openairdocs.org/saib/2025-08): INDICATING/RECORDING SYSTEM, Erroneous Illumination of Cabin Altitude Warning Lights in High Altitude Landing Mode. Issued Sep 8, 2025
- [SAIB AIR-21-12](https://openairdocs.org/saib/AIR-21-12): Thrust Reversers. Issued Aug 3, 2021
- [SAIB NE-19-03](https://openairdocs.org/saib/NE-19-03): Escape Slide Maintenance Tasks and Intervals - JASC 2565. Issued Feb 19, 2019
- [SAIB NM-18-33](https://openairdocs.org/saib/NM-18-33): Engine Fuel and Control. Issued Dec 17, 2018
- [SAIB NM-18-18](https://openairdocs.org/saib/NM-18-18): Equipment/Furnishings - First Observer's Seat Cup Holder. Issued Jul 2, 2018
- [SAIB NM-17-17](https://openairdocs.org/saib/NM-17-17): Oxygen System. Issued Jun 19, 2017
- [SAIB NM-17-10](https://openairdocs.org/saib/NM-17-10): Maintenance Practices. Issued Apr 13, 2017
- [SAIB NM-16-21](https://openairdocs.org/saib/NM-16-21): Flight Controls. Issued Aug 8, 2016
- [SAIB NM-15-03](https://openairdocs.org/saib/NM-15-03): Flight Controls. Issued Nov 24, 2014
- [SAIB NM-15-02](https://openairdocs.org/saib/NM-15-02): Cabin Equipment/Furnishings. Issued Nov 6, 2014
- [SAIB NM-12-11](https://openairdocs.org/saib/NM-12-11): Equipment/Furnishings: Buffet/Galleys. Issued Jan 10, 2012
- [SAIB NM-09-03](https://openairdocs.org/saib/NM-09-03): Engine Fuel and Control - Implementing Fuel Tank System Airworthiness Limitations. Issued Dec 11, 2008
- [SAIB NM-08-43](https://openairdocs.org/saib/NM-08-43): Cabin Equipment/Furnishings - Seats. Issued Sep 3, 2008
- [SAIB NM-08-24](https://openairdocs.org/saib/NM-08-24): Water/Waste: Freezing Potable Water Lines. Issued May 22, 2008
- [SAIB NM-07-47](https://openairdocs.org/saib/NM-07-47): Boeing Model 737 Series Forward Airstairs. Issued Sep 6, 2007
- [SAIB NM-06-57](https://openairdocs.org/saib/NM-06-57): Reports of damage to airplanes and to property on the ground caused by blue or clear ice falling from airplanes.. Issued Jul 27, 2006
- [SAIB NM-06-56](https://openairdocs.org/saib/NM-06-56): . Issued Jul 19, 2006
- [SAIB NE-08-17R3](https://openairdocs.org/saib/NE-08-17R3): Turbine Section - Propulsion Technology LLC Unapproved Repair. Issued May 28, 2014
- [SAIB NE-13-33R2](https://openairdocs.org/saib/NE-13-33R2): Turbine Engine Air Inlet Section - LP Turbine, Stage 1 Nozzle Vanes. Issued Jan 28, 2014
- [SAIB NE-12-29](https://openairdocs.org/saib/NE-12-29): Engine Fuel Distribution  CFM56-5B LPTACC Fuel Manifold. Issued Apr 27, 2012
- [SAIB NE-06-02](https://openairdocs.org/saib/NE-06-02): . Issued Oct 18, 2005
- [SAIB NE-13-33R1](https://openairdocs.org/saib/NE-13-33R1) (historical): Turbine Engine Air Inlet Section - LP Turbine, Stage 1 Nozzle Vanes. Issued Jun 24, 2013
- [SAIB NE-13-33](https://openairdocs.org/saib/NE-13-33) (historical): Turbine Engine Air Inlet Section - LP Turbine, Stage 1 Nozzle Vanes. Issued May 13, 2013
- [SAIB NE-08-17R2](https://openairdocs.org/saib/NE-08-17R2) (historical): Turbine Section - Propulsion Technology LLC Unapproved Repair. Issued Mar 7, 2011
- [SAIB NE-08-17R1](https://openairdocs.org/saib/NE-08-17R1) (historical): Propulsion Technology LLC Unapproved Repair. Issued May 22, 2008
- [SAIB NE-08-17](https://openairdocs.org/saib/NE-08-17) (historical): Propulsion Technologies International Unapproved Repair. Issued May 14, 2008

## NTSB investigations

None matched to N21723.

## FAA accident and incident reports (1)

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [Incident 20251017021542I](https://openairdocs.org/incident/20251017021542I), Oct 17, 2025: Boeing 737-724 (N21723), Chicago, IL, Minor damage. While turning onto the lead in line for C11 at Chicago O'Hare the right wing tip of the B737 contacted the tail section of a B767 under tow.

## Service difficulty reports (81, newest 50)

As reported by operators and repair stations. Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model.

- [SDR CALA2025121912270](https://openairdocs.org/sdr/CALA2025121912270), Dec 18, 2025: FUSE. BLOWN. ALL THREE EMERGENCY EXIT LIGHTS INOPERATIVE AT THE LT OVERWING EXIT. REPLACED THE FUSES IN M1668 POWER SUPPLY 33-51-06-960-804.. EMERGENCY EXIT LIGHTS OP CKS GO
- [SDR CALA2025121812222](https://openairdocs.org/sdr/CALA2025121812222), Dec 16, 2025: BATTERY PACK. NO TEST. EMERGENCY LIGHT BATTERY M1672 FAILS CAPACITY CHECK AND REQUIRES REPLACEMENT. REPLACED THE BATTERY M1672, OPS CHECKED GOOD IAW MM #33-51-06-200-801.
- [SDR CALA2025121812221](https://openairdocs.org/sdr/CALA2025121812221), Dec 16, 2025: BATTERY PACK. NO TEST. EMERGENCY LIGHT BATTERY M1669 FAILED A CAPACITY CHECK & REQUIRES REPLACEMENT. REPLACED EMERGENCY BATTERY M1669, OPS CHECKED GOOD IAW MM 33-51-06-200-801.
- [SDR CALA2025121712196](https://openairdocs.org/sdr/CALA2025121712196), Dec 16, 2025: BATTERY PACK. NO TEST. EMERGENCY LIGHT BATTERY M1675 FAILED A CAPACITY CHECK AND REQUIRES REPLACEMENT. REMOVED AND REPLACED THE BATTERY PACK IAW AMM 33-51-06-960-805, OPS CHKD GOOD.
- [SDR CALA2025121712194](https://openairdocs.org/sdr/CALA2025121712194), Dec 16, 2025: BATTERY PACK. NO TEST. EMERGENCY LIGHT BATTERY M1674 FAILED A CAPACITY CHECK AND REQUIRES REPLACEMENT. R & R THE BATTERY PACK IAW AMM 33-51-06-960-805 OPS CHK GOOD
- [SDR CALA2025102110339](https://openairdocs.org/sdr/CALA2025102110339), Oct 18, 2025: WINGLET. GROUND DAMAGE. ON TAXI IN RIGHT WING HIT ANOTHER AIRCRAFT BEGAN REMOVAL OF RIGHT WINGLET REF AMM 57-21-21-000-801. UP TO STEP 2. H(3) ADD EMP:U425084 CONTINUED FROM STEP 2. H 
- [SDR CALA2025090908657](https://openairdocs.org/sdr/CALA2025090908657), Sep 5, 2025: SLIDE. DISLODGED. FWD SVC DDOR SLIDE OUT OF BUSSEL SLIDE PACK NOT OUT OF SLIDE PACK COVER. EXCESS GIRT MATERIAL PULLED OUT DUE TO ROUGH HANDLING OF GIRT BAR. REPOSITIONED EXCESS 
- [SDR CALA2025082007954](https://openairdocs.org/sdr/CALA2025082007954), Aug 16, 2025: GIRT BAR. OUT OF LIMITS. DOOR 2R SLIDE IS TOUCHING CABIN FLOOR VERFIED WHEN WE TRIED TO CLOSE R2 DOOR THE SLIDE TOUCHING THE DOOR EDGE AND UNABLE TO CLOSE THE DOOR. REMOVED R2 DOOR SLID
- [SDR CALA2025070106122](https://openairdocs.org/sdr/CALA2025070106122), Jun 28, 2025: ROLLER. WORN. REVERSER LIGHT LIGHT ON, THRUST REVERSER OPS NORMALLY ENGINE 1 REQUESTING MEL 7801A FOR #1 ENGINE THRUST REVERSER. COMPLIED WITH. THRUST REVERSER LOCKED OUT. OB
- [SDR CALA2025051304641](https://openairdocs.org/sdr/CALA2025051304641), May 9, 2025: SIGHT GAUGE. NO DISCREPANCY. FA REPORTS DOOR 1L SLIDE SIGHT GAUGE SHOWING BOTH GREEN AND RED. INSPECTED SLIDE PRESSURE REF AMM 25-66-01-200-801 AND FOUND SLIDE BOTTLE PRESSURE IS JUST WITHI
- [SDR CALA2024122301620](https://openairdocs.org/sdr/CALA2024122301620), Dec 20, 2024: BULB. INOPERATIVE. EMERGENCY EXIT SIGN ABOVE EMERGENCY EXIT ROW LIGHT INOP ALL BULBS IN SIGN ARE BLOWN OUT, NEED 12 M&E PN 29-3351-3-0015 RE-LAMPED EMERGENCY EXIT SIGN NO FIX RE-L
- [SDR CALA2024121901577](https://openairdocs.org/sdr/CALA2024121901577), Dec 18, 2024: POWER SUPPLY. NO TEST. EMERGENCY LIGHTS AT ISLE 12-21 ARE INOP REPLACED POWER SUPPLY M1669, EMERGENCY LIGHTS OPS CHECKS GOOD. REF WDM 33-51-21 AND AMM 33-51-06
- [SDR CALA2024102302705](https://openairdocs.org/sdr/CALA2024102302705), Oct 16, 2024: WINDOW FRAME. DAMAGED. 737NG -LH SIDE NUMBER 3 WINDOW FRAME POST - PERMANENT REPAIR. - REF STEP 37A OF EA, SINCE 2D EDGE MARGEN COULD NOT BE MAINTAIND EXTEND FRAME CUT PER AVO 723-24-
- [SDR CALA2024072400280](https://openairdocs.org/sdr/CALA2024072400280), Jul 24, 2024: PANEL. MISSING. PDA 1 RAMP FOUND AIRCRAFT ARRIVED WITH MISSING PANEL. PANEL IS NUMBER 194E. AIRCRAFT ARRIVED FROM RDU FLIGHT NUMBER 1878 ON 7-21-24. NO FURTHER DAMAGE ON AIRCRA
- [SDR CALA2024050801394](https://openairdocs.org/sdr/CALA2024050801394), May 7, 2024: SHEAR TIE. CORRODED. SUPPORT TASK AFT CARGO COMPARTMENT SHEAR TIE CORRODED AT STA 747 AND BETWEEN STR26L-STR27L. REF TO PEMCO NR 15069.0467 REMOVED AND REPLACED AFT CARGO SHEAR-TIE 
- [SDR CALA2024050801393](https://openairdocs.org/sdr/CALA2024050801393), May 7, 2024: SHEAR TIE. CORRODED. SUPPORT TASK AFT CARGO COMPARTMENT, SHEAR TIE CORRODED AT STA 807 AND BETWEEN STR 26L AND STR 27L. REF TO PEMCO NR 15069.0474 REMOVED AND REPLACED AFT CARGO SHE
- [SDR CALA2024050801392](https://openairdocs.org/sdr/CALA2024050801392), May 7, 2024: SHEAR TIE. CORRODED. SUPPORT TASK AFT CARGO COMPARTMENT, SHEAR TIE CORRODED AT STA 847 BETWEEN STR 26L AND STR 27L. REMOVED AND REPLACED AFT CARGO SHEAR-TIE AT STA 847 BETWEEN STR 2
- [SDR CALA2024050201299](https://openairdocs.org/sdr/CALA2024050201299), Apr 26, 2024: STRINGER. CORRODED. SUPPORT TASK AFT CARGO COMPARTMENT STR 27L,SPLICE CORRODED AT STA 887. REF TO PEMCO NR 15069.0413 REMOVED AND REPLACED NEW SPLICE STA 887 STR 27L AFT CARGO IAW 
- [SDR CALA2024050201300](https://openairdocs.org/sdr/CALA2024050201300), Apr 22, 2024: STRINGER. DAMAGED. EXTERIAL FUSELAGE SKIN HAS 2EA POPPING RIVET HEADS AND BULGING BETWEEN FASTENERS STA 1080-1088 AND STR 22L JUST AFT OF TOILET SERVICE DOOR. REF TO PEMCO NR 1506
- [SDR CALA2024050301304](https://openairdocs.org/sdr/CALA2024050301304), Apr 7, 2024: BEARING. CRACKED. UPON REMOVAL OF RH HORIZ STAB CENTER HINGE PIN, FOUND RH CENTER HINGE FITTING BEARING CRACKED IN MULTIPLE LOCATIONS. REFER TO PEMCO NR. 15069.0775. REMOVED AND 
- [SDR CALA2024050301303](https://openairdocs.org/sdr/CALA2024050301303), Apr 7, 2024: BEARING. CRACKED. UPON REMOVAL OF LH CENTER HINGE PIN, FOUND LH CENTER HINGE FITTING BEARING CRACKED. REFER TO PEMCO NR. 15069.0777. REMOVED AND REPLACED LH STAB, CENTER HINGE FI
- [SDR CALA2023112903498](https://openairdocs.org/sdr/CALA2023112903498), Nov 28, 2023: ROD. BROKEN. LOUD NOSE GEAR NOISE DURING RETRACTION ON DEPARTURE. EXCESSIVE NOISE WITH GEAR UP. FOUND RIGHT NLG DOOR LINKAGE SEPARATED. PICS ADDED PICS ADDED R+R NLG WHEEL W
- [SDR CALA2023112403457](https://openairdocs.org/sdr/CALA2023112403457), Nov 23, 2023: TRANSMITTER. INOPERATIVE. HYD SYSTEM "A" QTY DROPPING INFLIGHT--CREW STATED 71 PERCENT AND DROPPING - AIR RETURN TO IAH PERFORMED DEU 1&2 BITE CHK PER AMM 31-62-21-860-003. DEU1&
- [SDR CALA2023080902464](https://openairdocs.org/sdr/CALA2023080902464), Aug 5, 2023: REGULATOR. INOPERATIVE. CABIN ALT WARNING AT FL 400 W/ CABIN ALT 10K+ INDICATIONS SHOWED HIGH PRESS DIFF W/ HIGH CABIN. UPDATED MAA CODE FIX USING VENDOR MAA SCREEN. PLEASE CONTACT TOM
- [SDR CALA2023050801406](https://openairdocs.org/sdr/CALA2023050801406), May 8, 2023: LANDING GEAR. WARNING MESSAGE. ON FINAL APP WHEN GEAR AND FLAPS 15 MOMENTRY GEAR HORN AND GEAR USAFE LONGER THAN NORM COMPLETED MAIN LANDING GEAR OPERATIONAL TEST PER AMM 32-09-10-740-801. NO
- [SDR CALA2023041901178](https://openairdocs.org/sdr/CALA2023041901178), Apr 19, 2023: DIFFUSER. UNKNOWN. LFT PACK TRIP OFF ILLUMINATED L/H PACK SECONDARY HEAT EXCHANGER PLENUM CHECK VALVE MISSING PARTS UPDATE UPDATE PHOTO R/R LH PLENUM AND DIFFUSER IAW AMM 21-51-03
- [SDR CALA2022062701591](https://openairdocs.org/sdr/CALA2022062701591), Jun 27, 2022: SCREW. MISSING. PDA 3 SCREW MISSING FROM #2 ENGINE PANEL 411 BL LOG NOTED
- [SDR CALA2022032500787](https://openairdocs.org/sdr/CALA2022032500787), Mar 25, 2022: SERVICE PANEL. MISSING. PDA 2 LAV SERVICE PANEL MISSING ON ARRIVAL. PLACED ON MEL PLACED ON MEL INREFERENCE TO GMM 02-30-95 APPROVED UPDATE, ADDING PICTURE AND SETTING SDR TO YES FOR P
- [SDR CALA2022031400661](https://openairdocs.org/sdr/CALA2022031400661), Mar 14, 2022: NONE. INOPERATIVE. TOILET FLUSH SYSTEM DOES NOT FLUSH ALL TOILETS PERFORMED OPS TEST OF ALL TOILETS PER AMM 38-32-00-700-802. OPS TEST GOOD. ALL TOILETS FLUSHED NORMALLY MULTIPLE 
- [SDR CALA2021112302162](https://openairdocs.org/sdr/CALA2021112302162), Nov 22, 2021: NONE. NONE. PDA 1 A SET OF CHOCKS DEPARTED THE AIRCRAFT DURING DEPARTURE OUT OF EWR FLT2077 ON 11/22/2021. WE ARE NOT SURE WHERE EXACTLY THE CHOCKS WERE LOCATED BEFORE THEY
- [SDR CALA2021111702125](https://openairdocs.org/sdr/CALA2021111702125), Nov 17, 2021: SLIDE. DEPLOYED. DOOR 1R PARTIALLY DEPLOYED SLIDE DEPLOYED SLIDE-NOT INFLATED/FEL L OUT CASE LOCKING FOR MX FERRY UNLOCKED TO CREATE MAA FOR STT ON CALL MX LOCKED BY TOMC UPDATE
- [SDR CALA2021041400449](https://openairdocs.org/sdr/CALA2021041400449), Apr 12, 2021: LIGHT. BROKEN. SEAT ROW 11 ABC EMERGENCY LIGHT INOP.
- [SDR CALA2021040600437](https://openairdocs.org/sdr/CALA2021040600437), Apr 6, 2021: SHEAR PLATE. CRACKED. B737-57-4-1262 SHEAR FITTING AT STA540 RBL15.04 IS CRACKED. SP T 6205861 REMOVED AND REPLACED SHEAR FITTING AT STA 540 RBL 15.04IAW B737- 700 SRM 51-40-02. SSFR
- [SDR CALA2021040500419](https://openairdocs.org/sdr/CALA2021040500419), Apr 3, 2021: FITTING. CRACKED. B737-57-4-1262 SHEAR FITTING AT STA 540 LBL 15.04 IS CRACKED. REMOVED AND REPLACED SHEAR FITTING AT STA 540 LBL 15.04 IAW B737 -700 SRM 51-40-02 AND EC/RA 5714-
- [SDR CALA2021040500418](https://openairdocs.org/sdr/CALA2021040500418), Apr 3, 2021: FITTING. CRACKED. B737-57-4-1262 SHEAR FITTING AT STA 540 RBL 15.04 IS CRACKED. SP T 6205861 . LOG PAGE OPEN. MORE DETAILS AWAITED.
- [SDR CALA2021040500417](https://openairdocs.org/sdr/CALA2021040500417), Apr 3, 2021: FITTING. CRACKED. B737-57-4-1262 SHEAR FITTING AT STA 540 RBL 6.14 IS CRACKED. REMOVED AND REPLACED SHEAR FITTING AT STA 540 RBL 6.14 IAW B737- 700 SRM 51-40-02 AND EC/RA 5714-01
- [SDR CALA2018050201219](https://openairdocs.org/sdr/CALA2018050201219), May 1, 2018: FLOORBEAM. CORRODED. MAIN CABIN FLOORBEAM HAS CORROSION AT STA 312 LBL-12. BLENDED OUT DAMAGE AND INSTALLED REPAIR STRAP PER ECRA 5315- 01097 REV A.
- [SDR CALA2018050201218](https://openairdocs.org/sdr/CALA2018050201218), May 1, 2018: FLOORBEAM. CORRODED. MAIN CABIN FLOORBEAM HAS CORROSION AT STA 328 RBL 25. SPLICED IN NEW SECTION OF FLOORBEAM UPPER CHORD FROM RBL 1 TO RBL 41 PER ECRA 5315-01098.
- [SDR CALA2018043001199](https://openairdocs.org/sdr/CALA2018043001199), Apr 29, 2018: FRAME. CRACKED. LEFT BS 727 LOWER FRAME WEB CRACKED AT FASTENER HOLE, 3 O'CLOCK AND 9 O'CLOCK POSITION. CRACK EXTENDS O/B 0.300" FROM FASTENER HOLE AND I/B FROM FASTENER HOLE T
- [SDR CALA2018043001212](https://openairdocs.org/sdr/CALA2018043001212), Apr 25, 2018: FLOORBEAM. CORRODED. CABIN FLOORBEAM BS 986, RBL 29 TO RBL 44 CORRODED. REPAIRED THE FLOORBEAM TEE IAW SRM 53-70-51, REPAIR 4, ALTERNATIVE 1.
- [SDR CALA2017122404583](https://openairdocs.org/sdr/CALA2017122404583), Dec 24, 2017: POWER SUPPLY. INOPERATIVE. EMERGENCY LIGHTS IN BULL NOSE AT ROWS 23ABC, 22DEF, & 12DEF INOPERATIVE. FOUND A LOOSE CONNECTOR AT BS 706. SECURED AND OPS CHECKED OK ON SEAT ROW 23 ABC REF AM
- [SDR CALA2017121604471](https://openairdocs.org/sdr/CALA2017121604471), Dec 16, 2017: OVEN. SPARKS. OVEN SMOKING OR SPARKING 205 REMOVED OVEN CONTENTS. FOUND RESIDUAL FROM PREVIOUS FLT. CLEANED AND OPS CHK''D OVEN. OK TO CONTINUE. OPS CHKS NORMAL.
- [SDR CALA2017050501280](https://openairdocs.org/sdr/CALA2017050501280), May 5, 2017: LIGHT. INOPERATIVE. L1 DOOR EXTERIOR EMERGENCY LIGHT INOP. RELAMP PER AMM 33-51-04-960-801. CK NORMAL.
- [SDR CALA2017042201109](https://openairdocs.org/sdr/CALA2017042201109), Apr 22, 2017: BATTERY PACK. DISCHARGED. DURING INTERIOR INSP OF ACFT DISCOVERED EMERGENCY LIGHTS AT ROWS 3 - 11 ABC ON SIDE OF SEATS ARE INOP. REPLACED BATTERY PACK & POWER SUPPLY PER AMM 33-51-06. OP
- [SDR CALA2017030400524](https://openairdocs.org/sdr/CALA2017030400524), Mar 4, 2017: BATTERY PACK. DISCHARGED. SEAT 4ABC TO 11ABC EMERGENCY LIGHT WOULD NOT TEST. CHARGED THE BATTERY PACKS. OPS CHECKED NORMAL.
- [SDR CALA2017021700382](https://openairdocs.org/sdr/CALA2017021700382), Feb 17, 2017: POWER SUPPLY. NO TEST. BULL NOSE EMERGENCY LIGHTS FROM SEAT ROWS 23-32, LIGHTS REMAINS ON FOR LESS THAN 15 MINUTES AFTER FULL CHARGE, FAILS BATTERY PACK CAPACITY CHECK. R & R THE POWE
- [SDR CALA2016031100159](https://openairdocs.org/sdr/CALA2016031100159), Mar 10, 2016: CONTROL BOX. FAILED. FLIGHT DECK DOOR FAILED TO REMAIN LOCKED IN FLIGHT. FOUND ELEC CONTROL BOX FAILED. REPLACED THE SAME IAW TASK 52-52- 02-800-801C12. OPERATIONS CHECKED NORMAL.
- [SDR CALA2016020100077](https://openairdocs.org/sdr/CALA2016020100077), Jan 28, 2016: DOOR FRAME. CRACKED. R1 DOOR FRAME BELOW THE BOX HANDLE MECHANISM, BOLT ATTACHMENT HOLE, JUST AFT OF DOOR TORQUE TUBE HAS A CRACK ALTER ACFT NOSE. R & R BEAM IAW SRM 51-40-02 & DWGS
- [SDR CALA2014091101222](https://openairdocs.org/sdr/CALA2014091101222), Sep 11, 2014: CIRCUIT BREAKER. POPPED. ON APPROACH, UPON BRINGING LG LEVER DOWN WE DID NOT GET MAIN GEAR DOWN INDICATION, ALL 3 LIGHTS INOPERATIVE. ALTERNATE LG INDICATORS SHOWED 3 GREEN. UPON INSPEC
- [SDR CALA2013081200554](https://openairdocs.org/sdr/CALA2013081200554), Aug 10, 2013: CHARGER. INOPERATIVE. EMERGENCY LIGHT INOPERATIVE FROM ROW 22 AFT. R & R BATTERY AND CHARGER. OPS CHECKED GOOD.

All 81: https://openairdocs.org/aircraft/N21723/reports.md

## STCs that may be installed (OpenAirDocs) (830, 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 (Boeing 737-724)

- [STC ST03438NY](https://openairdocs.org/stc/ST03438NY): Installation of Adams Rite Lavatory Equipment. Delta Engineering Corporation
- [STC ST04669CH](https://openairdocs.org/stc/ST04669CH): Installation of Honeywell Advanced Communications and Entertainment System (ACES). Honeywell Aerospace
- [STC ST09933AC](https://openairdocs.org/stc/ST09933AC): Expansion of parameters in the digital flight data acquisition unit (DFDAU). L2 Aviation
- [STC ST02269NY](https://openairdocs.org/stc/ST02269NY): Installation of Self Illuminating Floor Path Marking System. Lufthansa Technik AG
- [STC ST12461IB](https://openairdocs.org/stc/ST12461IB): Installation of Cockpit Voice Recorder with optional RIPS Upgrade. Mid- Canada Mod Center
- [STC ST00885LA](https://openairdocs.org/stc/ST00885LA): Installation of fire extinguisher cartridges as replacements for Pacific Scientific fire extinguisher cartridges in fire extinguisher bottles. AMETEK AMERON, LLC d/b/a MASS Systems
- [STC ST12443LA](https://openairdocs.org/stc/ST12443LA): Installation of Teledyne Controls Edge Computing Platform (ECP). Teledyne Controls, LLC
- [STC ST04671CH](https://openairdocs.org/stc/ST04671CH): Installation of Southwest Airlines Interior Reconfiguration for Extended Leg Room (ELR) Cabin. Astronics Connectivity Systems and Certification Corp
- [STC ST12382IB](https://openairdocs.org/stc/ST12382IB): IHOS eXconnect System Installation. Boeing Ireland Limited
- [STC ST09927AC](https://openairdocs.org/stc/ST09927AC): Installation of a Gables Audio Management System. L2 Aviation
- [STC ST10928SC](https://openairdocs.org/stc/ST10928SC): Installation of an Iridium Communications System. L2 Aviation
- [STC ST00197IB](https://openairdocs.org/stc/ST00197IB): Installation of the Universal Quick Access Recorder (uQAR). Flight Data Technologies Inc
- [STC ST04040CH](https://openairdocs.org/stc/ST04040CH): Activation of Smart Runway and Smart Landing (SRSL) Runway Awareness Advisory System (RAAS) Functions for Honeywell Mark V and Mark V-A Enhanced Ground Proximity Warning Systems (EGPWS). Honeywell International Inc
- [STC ST02244SE](https://openairdocs.org/stc/ST02244SE): Interior Completion. Greenpoint Technologies, Inc
- [STC ST04815NY](https://openairdocs.org/stc/ST04815NY): Installation of Gogo FDX Satellite Connectivity Installation. ALOFT AeroArchitects
- [STC ST00555AT](https://openairdocs.org/stc/ST00555AT): Installation of Airshow 210 system. AIRCRAFT RECONFIG TECHNOLOGIES, LLC. Lists 737 Series
- [STC ST03631AT-D](https://openairdocs.org/stc/ST03631AT-D): Installation of Windscreen with Stretcher Access and Stowage Box., Aft of the L1 Entry Door. AIRCRAFT RECONFIG TECHNOLOGIES, LLC
- [STC ST03808AT-D](https://openairdocs.org/stc/ST03808AT-D): Installation of an Adapter Plate, Antenna, Radome and Structural Provisions for a Panasonic Global Communications Suite. AIRCRAFT RECONFIG TECHNOLOGIES, LLC
- [STC ST03809AT-D](https://openairdocs.org/stc/ST03809AT-D): Installation of Wiring and Systems Provision for a Panasonic Global Communications Suite. AIRCRAFT RECONFIG TECHNOLOGIES, LLC
- [STC ST03873AT-D](https://openairdocs.org/stc/ST03873AT-D): Life raft installation. AIRCRAFT RECONFIG TECHNOLOGIES, LLC
- [STC ST04274AT](https://openairdocs.org/stc/ST04274AT): Interior reconfiguration installation. AIRCRAFT RECONFIG TECHNOLOGIES, LLC
- [STC ST04382AT](https://openairdocs.org/stc/ST04382AT): Interior reconfiguration installation. AIRCRAFT RECONFIG TECHNOLOGIES, LLC
- [STC ST04390AT](https://openairdocs.org/stc/ST04390AT): Main Cabin Cargo Carry Provisions installation. AIRCRAFT RECONFIG TECHNOLOGIES, LLC
- [STC ST04391AT](https://openairdocs.org/stc/ST04391AT): Interior Configuration. AIRCRAFT RECONFIG TECHNOLOGIES, LLC
- [STC ST04392AT](https://openairdocs.org/stc/ST04392AT): Main Cabin Cargo Carry Provisions installation. AIRCRAFT RECONFIG TECHNOLOGIES, LLC
- [STC ST00952LA](https://openairdocs.org/stc/ST00952LA): Installation of Mass Systems fire extinguisher cartridges as replacements for Kidde fire extinguisher cartridges in fire extinguisher bottles. AMETEK AMERON LLC d/b/a MASS Systems
- [STC ST04328NY](https://openairdocs.org/stc/ST04328NY): The Manufacture and Installation of Exterior Placards, Labels and Signs is to be performed, installed. Libellule Monde Inc
- [STC ST03875NY](https://openairdocs.org/stc/ST03875NY): Installation of interior placards, signs and markings. Libellule Monde Inc
- [STC ST01721NY](https://openairdocs.org/stc/ST01721NY): Installation of a Head of State Executive Interior - Model 737-700IGW. PATS Aircraft LLC
- [STC ST01716NY](https://openairdocs.org/stc/ST01716NY): Installation of Auxiliary Fuel Systems. PATS Aircraft LLC
- [STC ST03405NY](https://openairdocs.org/stc/ST03405NY): Installation (with demod option) of an Connectivity Antenna. Delta Engineering Corporation
- [STC ST04831NY](https://openairdocs.org/stc/ST04831NY): Installation of Vortex Control Technologies Finlets. Kilroy Aviation LLC
- [STC ST12295IB](https://openairdocs.org/stc/ST12295IB): Installation of Cabin Modification. JET AVIATION AG
- [STC ST04531CH](https://openairdocs.org/stc/ST04531CH): Installation of Global Navigation Sciences (GNS) LUX LED Lamp. Global Navigation Science, Inc
- [STC ST04758NY](https://openairdocs.org/stc/ST04758NY): Installation of single cockpit USB charger. Eirtech Aviation Services Inc
- [STC ST02643LA](https://openairdocs.org/stc/ST02643LA): Installation of Stow Bin Protective Wear Strip. Vogt Aero LLC
- [STC ST02746NY](https://openairdocs.org/stc/ST02746NY): Installation of an advertisement container on the bottom of a seat back tray table. Atin OOH LLC
- [STC ST03218CH](https://openairdocs.org/stc/ST03218CH): Modify aircraft interior to match standard passenger cofigurations, IAW Global Onboard Partners MDL # 252013-737-MDL-02, Rev. N, dtd 1/4/22 or later FAA approved revisions. Atin OOH LLC
- [STC ST02908NY](https://openairdocs.org/stc/ST02908NY): Installation of a Panasonic Avionics Corporation Global Communications Suite (GCS) and/or In-Flight Entertainment (IFE). Delta Engineering Corporation
- [STC ST01143LA](https://openairdocs.org/stc/ST01143LA): Installation of Aerocon Engineering Company (AEC) Airstar. Aircraft Technical Development Inc. dba Aerocon Engineering Company
- [STC ST02829CH](https://openairdocs.org/stc/ST02829CH): Installation of Row 44 Broadband Antenna System Provisions. Anuvu IFC Corporation
- [STC ST02836CH-D](https://openairdocs.org/stc/ST02836CH-D): Installation and activation of a Row 44 Broadband System. Anuvu IFC Corporation
- [STC ST03235CH](https://openairdocs.org/stc/ST03235CH): Certification of Compatibility with Wireless Data Technologies. Anuvu IFC Corporation
- [STC ST03301NY](https://openairdocs.org/stc/ST03301NY): Installation and activation of a new Row 44 Wireless Broadband System. Anuvu IFC Corporation
- [STC ST04324CH](https://openairdocs.org/stc/ST04324CH): Installation of a retrofit satellite antenna and associated power supply unit on aircraft previously fitted with the Row 44 Broadband System. Anuvu IFC Corporation
- [STC ST00892LA](https://openairdocs.org/stc/ST00892LA): Installation of Emergency Vision Assurance System (EVAS). VisionSafe LLC
- [STC ST12193IB](https://openairdocs.org/stc/ST12193IB): Installation of SpaceX Starlink Satellite Internet System Tile Antenna, Router and power supply. Airhawke Aérospatial Inc
- [STC ST00030IB](https://openairdocs.org/stc/ST00030IB): Installation of Test Tech ELT. APTOZ EHF
- [STC ST04479AT](https://openairdocs.org/stc/ST04479AT): Installation of Flex-Combi Interior. Pemco World Air Services
- [STC ST09191AC](https://openairdocs.org/stc/ST09191AC): Installation of DeVore wing fwd position light assembly. (737 ALL). The Boeing Company

All 830: https://openairdocs.org/aircraft/N21723/stcs.md

## Earlier aircraft with N21723

The FAA can reassign an N-number once a registration is cancelled. These aircraft carried N21723 before.

- [Cancelled 1994-12-02](https://openairdocs.org/deregistered/N21723-1994-12-02): Piper PA-31-350, S/N 318152028. Exported to Chile. Owner: [Special Air Service Corp](https://openairdocs.org/faa-owner/SPECIAL%20AIR%20SERVICE%20CORP), [Miami, FL](https://openairdocs.org/faa-place/FL/Miami)
- [Cancelled 1967-06-29](https://openairdocs.org/deregistered/N21723-1967-06-29): Heideman-Bowlus B-3, S/N 3, built 1940. Owner: [Torgerson Russell Eugene](https://openairdocs.org/faa-owner/TORGERSON%20RUSSELL%20EUGENE), [El Cajon, CA](https://openairdocs.org/faa-place/CA/El%20Cajon)

## Related

- Other Boeing 737-724 aircraft: https://openairdocs.org/model/boeing-737-724/aircraft.md
- The CFM International CFM56 series engine: https://openairdocs.org/engine/cfm-international-cfm56-series.md

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