# Douglas DC-9-21

- Type: Aircraft model (FAA registry)
- Registry code: 302205A
- Manufacturer (registry): DOUGLAS
- Model: DC-9-21
- Aircraft type: Fixed wing multi engine
- Category: Airplane
- Engines: 2 · Turbo-jet
- Seats: 85
- Weight class: 20,000 lb and over
- Cruise speed: 315 mph
- Certification: Type certificated
- Data sheet: [TCDS A6WE](https://openairdocs.org/tcds/A6WE) (OpenAirDocs)
- Holder: The Boeing Company
- Registered aircraft: 1
- Page: https://openairdocs.org/model/douglas-dc-9-21

Model codes come from the FAA registry's reference file. ADs are matched to them by model name and maker.

## ADs that may apply (OpenAirDocs)

Matched to this model by model name and maker. Each AD's applicability may narrow it by serial number, part number or equipment.

- [AD 2026-13-15](https://openairdocs.org/ad/2026-13-15): Navigation · Boeing 707-100 Long Body, 707-200, 707-100B Long Body and 74 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 2025-09-11](https://openairdocs.org/ad/2025-09-11): Flight controls · Boeing DC-9-81 (MD-81), DC-9-82 (MD-82), DC-9-83 (MD-83) and 20 more. Effective Jun 12, 2025
- [AD 2024-20-02](https://openairdocs.org/ad/2024-20-02): Fuselage · Boeing 717-200, DC-9-11, DC-9-12 and 16 more. Effective Oct 21, 2024
- [AD 2023-12-15](https://openairdocs.org/ad/2023-12-15): Navigation · Boeing 707-100 Long Body, 707-200, 707-100B Long Body and 74 more. Effective Jun 21, 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 2018-03-04](https://openairdocs.org/ad/2018-03-04): Airspeed/Mach Indicator · Boeing 717-200, DC-9-11, DC-9-12 and 23 more. Effective Mar 16, 2018
- [AD 2016-03-06](https://openairdocs.org/ad/2016-03-06): Fuel · Boeing DC-9-11, DC-9-12, DC-9-13 and 21 more. Effective Mar 23, 2016
- [AD 2014-22-05](https://openairdocs.org/ad/2014-22-05): Fuselage · Boeing DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Dec 11, 2014
- [AD 2014-22-04](https://openairdocs.org/ad/2014-22-04): Fuselage · Boeing DC-9-11, DC-9-12, DC-9-13 and 13 more. Effective Dec 11, 2014
- [AD 2014-05-27](https://openairdocs.org/ad/2014-05-27): Navigation · Airbus A319-111, A319-112, A319-113 and 99 more. Effective May 2, 2014
- [AD 2011-21-08](https://openairdocs.org/ad/2011-21-08): Equipment/Furnishings · ATR - GIE Avions de Transport Régional ATR42-200, ATR42-300, ATR42-320 and 202 more. Effective Nov 23, 2011
- [AD 2011-12-01](https://openairdocs.org/ad/2011-12-01): Equipment/Furnishings · Airbus A300 B2-1A, A300 B2-1C, A300 B2-203 and 268 more. Effective Aug 1, 2011
- [AD 2011-07-04](https://openairdocs.org/ad/2011-07-04): Fuel · Boeing DC-9-14, DC-9-15, DC-9-15F and 12 more. Effective May 6, 2011
- [AD 2010-23-10](https://openairdocs.org/ad/2010-23-10): Wings · Boeing DC-9-14, DC-9-15, DC-9-15F and 12 more. Effective Dec 14, 2010
- [AD 2009-21-10 R1](https://openairdocs.org/ad/2009-21-10-R1): Oxygen · Airbus A300 B4-605R, A300 B4-620, A300 B4-622 and 138 more. Effective Feb 4, 2010
- [AD 2009-24-21](https://openairdocs.org/ad/2009-24-21): Landing gear · Boeing DC-9-14, DC-9-15, DC-9-15F and 12 more. Effective Jan 8, 2010
- [AD 2009-03-03](https://openairdocs.org/ad/2009-03-03): Fuel boost pump of the center tank · Boeing DC-9-14, DC-9-15, DC-9-15F and 12 more. Effective Mar 31, 2009
- [AD 2008-18-06](https://openairdocs.org/ad/2008-18-06): Tail cone slide · Protective rigid cover over the tail cone emergency evacuation… (Derlan STC ST735SO). Effective Jan 7, 2009
- [AD 2008-11-15](https://openairdocs.org/ad/2008-11-15): Fuel tank systems · Boeing 717-200, DC-9-11, DC-9-12 and 21 more. Effective Jul 3, 2008
- [AD 2008-06-27](https://openairdocs.org/ad/2008-06-27): Evacuation system's shear-pin · Airbus A300 B2-1A, A300 B2-1C, A300 B2-203 and 91 more. Effective Apr 28, 2008
- [AD 2008-03-12](https://openairdocs.org/ad/2008-03-12): Rudder pedal bracket · Boeing DC-8-11, DC-8-12, DC-8-21 and 47 more. Effective Mar 11, 2008
- [AD 2007-17-18](https://openairdocs.org/ad/2007-17-18): Static port heater assemblies · Boeing DC-9-11, DC-9-12, DC-9-13 and 20 more. Effective Oct 2, 2007
- [AD 2006-21-06](https://openairdocs.org/ad/2006-21-06): Structural inspection revisions · Boeing DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Nov 29, 2006
- [AD 2006-18-05](https://openairdocs.org/ad/2006-18-05): Disconnect panel · Boeing DC-9-14, DC-9-15, DC-9-15F and 12 more. Effective Oct 11, 2006
- [AD 2006-18-02](https://openairdocs.org/ad/2006-18-02): Replacing the clamp bases for the fuel vent pipe · Boeing DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Oct 4, 2006
- [AD 2006-10-14](https://openairdocs.org/ad/2006-10-14): Stop pad support fittings · Boeing 717-200, DC-9-11, DC-9-12 and 22 more. Effective Jun 21, 2006
- [AD 2006-07-08](https://openairdocs.org/ad/2006-07-08): Main fuselage frame · Boeing DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective May 5, 2006
- [AD 2006-06-04](https://openairdocs.org/ad/2006-06-04): Main landing gear (MLG) · Boeing DC-9-11, DC-9-12, DC-9-13 and 17 more. Effective Apr 20, 2006
- [AD 2006-01-02](https://openairdocs.org/ad/2006-01-02): Upper lock link assembly of the nose landing gear (NLG) · Boeing DC-9-14, DC-9-15, DC-9-15F and 18 more. Effective Feb 22, 2006
- [AD 2005-13-18](https://openairdocs.org/ad/2005-13-18): Battery terminal screws · Boeing DC-9-11, DC-9-12, DC-9-13 and 20 more. Effective Aug 1, 2005
- [AD 2005-07-18](https://openairdocs.org/ad/2005-07-18): Cargo configuration · Class E cargo compartment and pallet system (Aeronautical Engineers STC SA1993SO). Effective May 11, 2005
- [AD 2005-07-03](https://openairdocs.org/ad/2005-07-03): Rear spar of the left and right wings · Boeing DC-9-11, DC-9-12, DC-9-13 and 17 more. Effective May 4, 2005
- [AD 2004-25-14](https://openairdocs.org/ad/2004-25-14): Main landing gear (MLG) · Boeing DC-9-14, DC-9-15, DC-9-15F and 17 more. Effective Jan 20, 2005
- [AD 2004-22-01](https://openairdocs.org/ad/2004-22-01): Cargo restraint strap assemblies · Cargo restraint straps (Airline Container Manufacturing STC ST01004NY). Effective Dec 1, 2004
- [AD 2004-18-11](https://openairdocs.org/ad/2004-18-11): Outboard idler hinge fitting of the left and right wing · Boeing DC-9-14, DC-9-15, DC-9-15F and 12 more. Effective Oct 13, 2004
- [AD 2004-07-05](https://openairdocs.org/ad/2004-07-05): Engine Pylon Aft Upper Spar Straps (Caps) · Boeing DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective May 5, 2004
- [AD 2004-07-04](https://openairdocs.org/ad/2004-07-04): Ballast transformers · Boeing DC-9-14, DC-9-15, DC-9-15F and 12 more. Effective May 5, 2004
- [AD 2004-05-25](https://openairdocs.org/ad/2004-05-25): Seat Locking Pins · Boeing DC-9-14, DC-9-15, DC-9-15F and 18 more. Effective Apr 19, 2004
- [AD 2003-03-15 R1](https://openairdocs.org/ad/2003-03-15-R1): Airplane Flight Manual (AFM) - oxygen masks · Boeing 707-100 Long Body, 707-100B Long Body, 707-100B Short Body and 90 more. Effective Dec 22, 2003
- [AD 2003-17-07 R1](https://openairdocs.org/ad/2003-17-07-R1): Auxiliary power unit (APU) · Boeing DC-10-10, DC-10-10F, DC-10-15 and 57 more. Effective Sep 24, 2003
- [AD 2003-09-07](https://openairdocs.org/ad/2003-09-07): Left and right main landing gear (MLG) · Boeing DC-9-14, DC-9-15, DC-9-15F and 17 more. Effective Jun 5, 2003
- [AD 2002-26-10](https://openairdocs.org/ad/2002-26-10): Corners of the Forward Lower Cargo Doorjamb · Boeing DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Feb 10, 2003
- [AD 2002-26-08](https://openairdocs.org/ad/2002-26-08): Emergency Power Switch Knob on the Overhead Switch Panel in the Flight Compartment · Boeing DC-9-11, DC-9-12, DC-9-13 and 20 more. Effective Feb 10, 2003
- [AD 2002-26-13](https://openairdocs.org/ad/2002-26-13): Left and right generator power relays · Boeing DC-9-11, DC-9-12, DC-9-13 and 20 more. Effective Feb 6, 2003
- [AD 2002-25-04](https://openairdocs.org/ad/2002-25-04): Circuit breakers · Boeing DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Jan 17, 2003
- [AD 2002-21-09](https://openairdocs.org/ad/2002-21-09): Cockpit enclosure window sill · Boeing DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Nov 29, 2002
- [AD 2002-07-06](https://openairdocs.org/ad/2002-07-06): Upper and Lower Corners and Upper Center of the Door Cutout of the Aft Pressure Bulkhead · Boeing DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective May 14, 2002
- [AD 2002-04-01](https://openairdocs.org/ad/2002-04-01): Upper Lock Link Assembly of the Nose Landing Gear (NLG) · Boeing DC-9-11, DC-9-12, DC-9-13 and 21 more. Effective Mar 28, 2002
- [AD 2001-24-27](https://openairdocs.org/ad/2001-24-27): Rudder Pedal Adjuster Hub Assembly · Boeing DC-9-11, DC-9-12, DC-9-13 and 20 more. Effective Jan 16, 2002

Historical (superseded or no longer in force):

- [AD 2022-09-18](https://openairdocs.org/ad/2022-09-18) (historical): Navigation · Boeing 707-100 Long Body, 707-100B Long Body, 707-100B Short Body and 72 more. Effective May 23, 2022
- [AD 2012-18-05](https://openairdocs.org/ad/2012-18-05) (historical): Fuel · Boeing DC-9-11, DC-9-12, DC-9-13 and 21 more. Effective Oct 11, 2012
- [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 2006-07-25](https://openairdocs.org/ad/2006-07-25) (historical): Rudder pedal bracket · McDonnell Douglas DC-8-11, DC-8-12, DC-8-21 and 44 more. Effective May 16, 2006
- [AD 2005-19-08](https://openairdocs.org/ad/2005-19-08) (historical): Main landing gear (MLG) shock strut cylinder · McDonnell Douglas DC-9-14, DC-9-15, DC-9-15F and 12 more. Effective Oct 21, 2005
- [AD 2004-23-11](https://openairdocs.org/ad/2004-23-11) (historical): Center wing rear spar · Boeing DC-9-14, DC-9-15, DC-9-21 and 11 more. Effective Dec 20, 2004
- [AD 2003-17-07](https://openairdocs.org/ad/2003-17-07) (historical): Fire Extinguishers for the Engine and Auxiliary Power Unit (APU) · McDonnell Douglas DC-10-10, DC-10-10F, DC-10-15 and 60 more. Effective Sep 24, 2003
- [AD 2003-03-15](https://openairdocs.org/ad/2003-03-15) (historical): Airplane Flight Manual (AFM) - Oxygen Masks · Boeing 707 Series (all), 720 Series (all), 727 Series (all) and 75 more. Effective Mar 7, 2003
- [AD 2003-03-08](https://openairdocs.org/ad/2003-03-08) (historical): Eletrical connectors · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Mar 7, 2003
- [AD 2001-26-24](https://openairdocs.org/ad/2001-26-24) (historical): Transformer Ballast Assembly · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 14 more. Effective Feb 8, 2002
- [AD 98-26-09](https://openairdocs.org/ad/98-26-09) (historical): Fatigue Cracking In Doorstops And Doorjamb · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Jan 22, 1999
- [AD 98-08-24](https://openairdocs.org/ad/98-08-24) (historical): Fuselage Skin Or Doubler · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective May 22, 1998
- [AD 96-21-01](https://openairdocs.org/ad/96-21-01) (historical): Main Landing Gear Hydraulic Damper Assembly · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Nov 14, 1996
- [AD 74-08-09 R2](https://openairdocs.org/ad/74-08-09-R2) (historical): Waste Receptacles · Aero Spacelines 377, 377MG, 377SGT and 268 more. Effective Jul 29, 1996
- [AD 96-13-03](https://openairdocs.org/ad/96-13-03) (historical): Structural Integrity · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Jul 24, 1996
- [AD 96-02-05](https://openairdocs.org/ad/96-02-05) (historical): Rudder Pedals Adjuster Hub Assembly · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 20 more. Effective Mar 25, 1996
- [AD 95-12-25](https://openairdocs.org/ad/95-12-25) (historical): FIREX Pipe Assembly · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 20 more. Effective Jul 24, 1995
- [AD 95-04-01](https://openairdocs.org/ad/95-04-01) (historical): AFM - Limitations - Windshear · Boeing 727-100 Series, 727-200 Series, 737-100 Series and 54 more. Effective Mar 8, 1995
- [AD 94-03-01](https://openairdocs.org/ad/94-03-01) (historical): Maintenance Inspection Program · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Mar 14, 1994
- [AD 93-13-07](https://openairdocs.org/ad/93-13-07) (historical): Install Water Drain System · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 17 more. Effective Aug 18, 1993
- [AD 92-27-07](https://openairdocs.org/ad/92-27-07) (historical): Rudder Pedals Adjuster Hub Assembly · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 20 more. Effective Jan 22, 1993
- [AD 87-14-07 R1](https://openairdocs.org/ad/87-14-07-R1) (historical): Maintenance Inspection Program · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Dec 23, 1988
- [AD 77-14-19](https://openairdocs.org/ad/77-14-19) (historical): Engine Pylon · McDonnell Douglas DC-9-11, DC-9-12, DC-9-13 and 15 more. Effective Aug 23, 1977

All 230: https://openairdocs.org/model/douglas-dc-9-21/ads.md

## Information bulletins (advisory) (2)

- [SAIB NM-15-03](https://openairdocs.org/saib/NM-15-03): Flight Controls. Issued Nov 24, 2014
- [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

## Registered aircraft (1)

- [N127NK](https://openairdocs.org/aircraft/N127NK): [Perris Valley Airport Inc](https://openairdocs.org/faa-owner/PERRIS%20VALLEY%20AIRPORT%20INC), [Perris, CA](https://openairdocs.org/faa-place/CA/Perris), S/N 47361

## NTSB investigations

None matched to aircraft with this model.

## FAA accident and incident reports

None matched to aircraft with this model.

## Service difficulty reports (52, newest 50)

As reported by operators and repair stations, by the model named in the report.

- [SDR AALA201706219024](https://openairdocs.org/sdr/AALA201706219024), Jun 19, 2017: FRAME. CRACKED. THREE WAY CRACK IN THE RIGHT MAIN LANDING GEAR WHEEL WELL FORWARD FRAME. REPAIRED IAW DWG 53-10-00-12. AIRCRAFT WAS GROUNDED.
- [SDR WX0A02009A](https://openairdocs.org/sdr/WX0A02009A), Nov 2, 2002: DUCT. RUPTURED. LAS - TAIL COMPARTMENT HIGH TEMP ANNUNCIATOR INDICATION ILLUMINATED IN FLIGHT. AIRCRAFT RETURNED TO STATION WITHOUT INCIDENT. MAINTENANCE INSPECTED TAIL COMPART
- [SDR WXOA02009A](https://openairdocs.org/sdr/WXOA02009A), Nov 2, 2002: DUCT. CRACKED. TAIL COMP HIGH TEMP ANNUNCIATOR INDIC ILLUMINATED INFLIGHT. AC RETURNED TO STATION W/O INCIDENT. MAINT INSP TAIL COMP AND ASSOC PRESS DIST SYS FOR CAUSE OF HIGH
- [SDR WXOA02009](https://openairdocs.org/sdr/WXOA02009), Nov 2, 2002: DUCT. RUPTURED. LAS - TAIL COMPARTMENT HIGH TEMP ANNUNCIATOR INDICATION ILLUMINATED IN FLIGHT. AIRCRAFT RETURNED TO STATION WITHOUT INCIDENT. MAINTENANCE INSPECTED TAIL COMPART
- [SDR WXOA02007](https://openairdocs.org/sdr/WXOA02007), Sep 18, 2002: DRIVE GEAR. FAILED. ENROUTE, NR 1 ENGINE LOW OIL PRESSURE ANNUNCIATOR INDICATION ILLUMINATED. CREW COMPLIED WITH AOM EMERGENCY/ ABNORMAL PROCEDURES. PRECAUTIONARY INFLIGHT ENGINE S
- [SDR WX0A01003](https://openairdocs.org/sdr/WX0A01003), Jul 25, 2001: PAN. CRACKED. LCQ - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND AFT CARGO DOOR CRACKED AROUND RIVNUT FASTENER AT LOWER FORWARD CORNER. ROUTED OUT CRACK ON A
- [SDR WX0A01002](https://openairdocs.org/sdr/WX0A01002), Jul 25, 2001: AILERON. DELAMINATED. LCQ - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, LEFT AILERON INBOARD TAB DELAMINATION DETECTED ON LOWER OUTBOARD SIDE. DELAMINATION REPORTED TO BE
- [SDR WX0A01001](https://openairdocs.org/sdr/WX0A01001), Jul 25, 2001: ATTACH FITTING. CRACKED. LCQ - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, CRACKED DETECTED BY VISUAL INSPECTION AT VERTICAL STABILIZER LEFT DORSAL FIN ATTACH FITTING. HFEC 
- [SDR WX0A01007](https://openairdocs.org/sdr/WX0A01007), Jul 25, 2001: FUEL LINE. LEAKING. LCQ - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, MAIN FUEL SUPPLY HOSE ASSEMBLIES ON RIGHT AND LEFT ENGINES TO FUEL CONTROL UNITS REPORTED LEAKING.
- [SDR WX0A01008](https://openairdocs.org/sdr/WX0A01008), Jul 25, 2001: WIRE. CHAFED. LCQ - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND RIGHT ENGINE AC LOAD METER IN COCKPIT OVERHEAD PANEL TO HAVE CHAFED WIRES AT CONNECTOR MAINT
- [SDR WX0A01006](https://openairdocs.org/sdr/WX0A01006), Jul 25, 2001: JACKSCREW. WORN. LCQ - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, HORIZONTAL STABILIZER JACKSCREW FAILED END PLAY CHECK PER WORK CARD 0855, SB 27A362 AND AD 2000-15
- [SDR WX0A01005](https://openairdocs.org/sdr/WX0A01005), Jul 25, 2001: SKIN. CORRODED. LCQ - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, LEVEL 1 CORROSION WAS FOUND IN LOWER AFT FUSELAGE SKIN AT AFT JACK PAD AREA. CORROSION DAMAGE TO F
- [SDR WX0A01004](https://openairdocs.org/sdr/WX0A01004), Jul 25, 2001: SKIN. CRACKED. LCQ - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND FORWARD CARGO DOOR INNER SKIN CRACKED IN THE RADIUS BELOW AFT LATCH COVER. STOP DRILLED CRAC
- [SDR WXOA99031](https://openairdocs.org/sdr/WXOA99031), Nov 13, 1999: SLAT. DENTED. AMA - BIRD STRIKE REPORTED TO LEFT WING AT 8500 FT DURING DESCENT FOR LANDING. AIRCRAFT LANDED WITHOUT INCIDENT. BIRD STRIKE INSPECTION ACCOMPLISHED IAW DC-9 MM
- [SDR WXOA99030](https://openairdocs.org/sdr/WXOA99030), Oct 22, 1999: ANGLE. CORRODED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND LEVEL 1 CORROSION ON AFT STAIR ANGLE. REMOVED CORRODED ANGLE. FABRICATED REPAIR ANGLE AND IN
- [SDR WXOA99029](https://openairdocs.org/sdr/WXOA99029), Oct 22, 1999: BEAM. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND CRACK IN GALLEY SERVICE DOOR HORIZONTAL BEAM AFT EDGE. CRACK REPORTED APPROXIMATELY .240 INC
- [SDR WXOA99028](https://openairdocs.org/sdr/WXOA99028), Oct 22, 1999: FRAME. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND THREE CRACKES ON FUSELAGE FRAME STATION 718 AT STRINGER 17L. REMOVED DAMAGED MATERIAL. PERFO
- [SDR WXOA99027](https://openairdocs.org/sdr/WXOA99027), Oct 22, 1999: FRAME. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND 3.5 INCH CRACK IN RADIUS OF FUSELAGE FRAME STATION 737 AT LONGERON 17L. REMOVED DAMAGED SECT
- [SDR WXOA99026](https://openairdocs.org/sdr/WXOA99026), Oct 22, 1999: FRAME. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND CRACK IN AFT ACCESSORY COMPARTMENT RIGHT SIDE OF FRAME 859 AT LONGERON 13R NEAR LIGHTNING HO
- [SDR WXOA99025](https://openairdocs.org/sdr/WXOA99025), Oct 22, 1999: INTERCOSTAL. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND INTERCOSTAL CRACKED AT FORWARD AREA OF AFT CARGO DOOR JAMB. REMOVED DAMAGED INTERCOSTAL AND 
- [SDR WXOA99024](https://openairdocs.org/sdr/WXOA99024), Oct 20, 1999: DOUBLER. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, FOUND INTERNAL DOUBLER EDGE OF RUDDER BROKEN AT REFERENCE ZR99. REMOVED DAMAGED INTERNAL DOUBLER. 
- [SDR WXOA99023](https://openairdocs.org/sdr/WXOA99023), Oct 16, 1999: SHEAR TIE. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, NDT HFEC INSPECTION DETECTED AND APPROXIMATE 2 INCH LONG CRACK ON SHEAR TIE BETWEEN LONGERON L14 A
- [SDR WXOA99022](https://openairdocs.org/sdr/WXOA99022), Oct 16, 1999: SUPPORT. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, NDT HFEC INSPECTION OF FORWARD CARGO DORO PER OPS 4.735 DETECTED CRACKED AT AFT SIDE OF INTERCOSTA
- [SDR WXOA99021](https://openairdocs.org/sdr/WXOA99021), Oct 15, 1999: SHEAR TIE. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, NDT HFEC INSPECTION DETECTED CRACK OF APPROXIMATELY 2 INCH LONG ON SHEER CLIP BETWEEN LONGERON L15
- [SDR WXOA99020](https://openairdocs.org/sdr/WXOA99020), Oct 15, 1999: SKIN. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, CRACK DETECTED AT UPPER AFT AREA OF LEFT MLG DOOR NEAR HINGE. STOP DRILLED CRACK, INSTALLED DOUBLE
- [SDR WXOA99019](https://openairdocs.org/sdr/WXOA99019), Oct 15, 1999: ANGLE. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, NDT HFEC DETECTED A CRACK ON ANGLE P/N 9912243-10 AT THE RIGHT PYLON BULKHEAD LOWER FRONT SPAR (F/
- [SDR WXOA99018](https://openairdocs.org/sdr/WXOA99018), Oct 15, 1999: SKIN. DENTED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, DENT DISCOVERED ON RIGHT SIDE OF RUDDER BETWEEN RIBS 23 AND 24, LOCATED APPROXIMATELY 18 INCH FROM
- [SDR WXOA99017](https://openairdocs.org/sdr/WXOA99017), Oct 15, 1999: FITTING. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, NDT HFEC INSPECTIN PERFORMED PER OPS 4.751 OF LEFT PYLON 'BATH TUB' FITTING. INDICATION OF CRACK N
- [SDR WXOA99016](https://openairdocs.org/sdr/WXOA99016), Oct 15, 1999: ANGLE. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, NDT HFEC INSPECTION PERFORMED PER OPS 4.735 AT FORWARD CARGO DOOR. INDICATION OF CRACK NOTED ON IN
- [SDR WXOA99015](https://openairdocs.org/sdr/WXOA99015), Oct 14, 1999: DOOR PAN. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, CRACK DETECTED AT PAN AND INTERCOSTAL INTERSECTION OF TOP FORWARD CORNER OF FORWARD CARGO DOOR. FA
- [SDR WXOA99014](https://openairdocs.org/sdr/WXOA99014), Oct 14, 1999: ANGLE. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, NDT HFEC INSPECTION DETECTED CRACK INDICATION ON FORWARD CARGO DOOR AT FORWARD SIDE OF LOWER AFT D
- [SDR WXOA99013](https://openairdocs.org/sdr/WXOA99013), Oct 14, 1999: LONGERON. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, NDT HFEC INSPECTION DETECTED CRACK INDICATION AT LONGERON 16, FUSELAGE STATION 786 RIGHT. CRACK EV
- [SDR WXOA99012](https://openairdocs.org/sdr/WXOA99012), Oct 14, 1999: PANEL. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, VERTICAL STABILIZER ACCESS PANEL 3806 HAS CRACK PROPOGATING FROM EXISTING STOP DRILL. STOP DRILLED
- [SDR WXOA99011](https://openairdocs.org/sdr/WXOA99011), Oct 14, 1999: DUCT. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, VERTICAL STABILIZER AIR INTAKE DUCT AT 12 O'CLOCK POSITION HAS A CRACK APPROXIMATELY .25 INCHES LO
- [SDR WXOA99010](https://openairdocs.org/sdr/WXOA99010), Oct 14, 1999: FRAME. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, NDT HFEC INSPECTION AT STATION 766 RIGHT SIDE, BETWEEN LONGERON 15 AND 16, DETECTED CRACK IN RADIU
- [SDR WXOA99009](https://openairdocs.org/sdr/WXOA99009), Oct 14, 1999: SUPPORT. CORRODED. MHV - DURING AIRCRAFT SCHEDULED INSPECTON AT REPAIR STATION, LEVEL 1 SURFACE CORROSION DETECTED AT THREE PLACES IN AFT RIGHT LAV FLOOR SUPPORT FRAME, STATIONS 7
- [SDR WXOA99008](https://openairdocs.org/sdr/WXOA99008), Oct 12, 1999: CLIPS. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, CRACKS DETECTED IN TWO CLIPS ON RIGHT ENGINE LOWER APRON. REMOVED CRACKED CLIPS, FABRICATED REPAIR
- [SDR WXOA99007](https://openairdocs.org/sdr/WXOA99007), Oct 11, 1999: ANGLE. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, PERFORMED NDT HFEC INSPECTION PER OPS 4.735. RESULTS OF INSPECTION DETECTED CRACK ON ANGLE P/N 991
- [SDR WXOA99006](https://openairdocs.org/sdr/WXOA99006), Oct 6, 1999: FRAME. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, AFT ACCESSORY COMPARTMENT FRAME 859 AT LONGERON L13 IS CRACKED BY LIGHTNING HOLE. STOP DRILLED CRA
- [SDR WXOA99005](https://openairdocs.org/sdr/WXOA99005), Oct 6, 1999: DUCT. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, CRACK DETECTED IN COOLING EXHAUST DUCT AT FUSELAGE STATION 261 AND LONGERON L21. WELDED CRACKS TWO
- [SDR WXOA99004](https://openairdocs.org/sdr/WXOA99004), Oct 6, 1999: BRACKET. CRACKED. MHV - DURING AIRCRAFT SCHEDULED INSPECTION AT REPAIR STATION, LEFT WING SLAT TRACK NR 2 FORWARD LOWER PANEL BRACKET CRACKED AND OUTBOARD BRACKET HOLE ELONGATED.
- [SDR WXOA98001](https://openairdocs.org/sdr/WXOA98001), Oct 14, 1998: CONNECTOR. FAILED. FAT - DURING ACCOMPLISHMENT OF SCHEDULED AIRCRAFT MAINTENANCE, FOUND DAMAGED ELECTRICAL WIRING CONNECTOR AT PRODUCTION SPLICE FOR ROWS 9-10 (RT) CABIN INTERIOR 
- [SDR GTIA9700290](https://openairdocs.org/sdr/GTIA9700290), May 21, 1997: BATTERY PACK. DISCHARGED. DTW - FLT 621 - RIGHT OVERWING EXIT LIGHT INOPERATIVE. FOUND LIGHT SOCKET BROKEN AND BATTERY PACK BATTERIES LOW, REPLACED LIGHT ASSY AND BATTERY PACK BATTERIES.
- [SDR GTIA9700251](https://openairdocs.org/sdr/GTIA9700251), Mar 13, 1997: PS4 LINE. BROKEN. CHS - FLT 301 - RIGHT NR 2 ENGINE LOST PARTIAL POWER FROM 1.95 TO 1.6 FOR A FEW MINUTES AND THEN SPOOLED DOWN TO IDLE. WOULD NOT PRODUCE MORE THAN 1.1 FPR. FOLL
- [SDR GTIA9700187](https://openairdocs.org/sdr/GTIA9700187), Mar 8, 1997: CONNECTOR. LOOSE. ACY - FLT 514 - DURING PUSH BACK AT RSW, APU SHUT ITSELF DOWN FOR NO REASON. A RESTART WAS SUCCESSFUL, BUT APU AGAIN SHUT ITSELF OFF AFTER APPROXIMATELY 30 SECO
- [SDR GTIA9700238](https://openairdocs.org/sdr/GTIA9700238), Feb 27, 1997: SWITCH. FAILED. DTW - FLT 905 - LEFT THRUST REVERSER UNLOCK LIGHT STAYED ON AFTER DEPLOYMENT. DEFERRED IAW MEL 78-1, CAT 'C' DMI NR 00210. REMOVED AND REPLACED REVERSER UNLOCK 
- [SDR 96NK208](https://openairdocs.org/sdr/96NK208), Sep 26, 1996: CONNECTOR. CORROSION. LOG PAGE 028581. AIR RETURN. AFTER TAKEOFF, GEAR RETRACTED. LEFT MAIN LANDING GEAR INDICATED DOWN WITH NO RED (UNSAFE) LIGHT. DOOR LIGHT WAS OUT. GEAR INDICATIO
- [SDR GTIA96NK189](https://openairdocs.org/sdr/GTIA96NK189), Aug 16, 1996: RELEASE MECH. OUT OF ADJUST. LOG PAGE 027001. TAIL CONE FAILED TO RELEASE DURING TAIL CONE RELEASE SYSTEM CHECK. ADJUSTED TAIL CONE RELEASE SYSTEM MECHANISM IAW DC-9 MM 53-50-0. OPS CHECKS 
- [SDR 96ZZZX3274](https://openairdocs.org/sdr/96ZZZX3274), Mar 22, 1996: BAL RESISTOR. OUT OF ADJUST. BOS/BOS - FLT 361 - ABORTED TAKEOFF, NR 2 ENGINE EGT WAS ERRATIC. THE NR 2 ENGINE EGT GAUGE STOPS AT APPROXIMATELY 350 DEGREES WHEN TAKEOFF POWER WAS APPLIED. F
- [SDR 96ZZZX2843](https://openairdocs.org/sdr/96ZZZX2843), Mar 22, 1996: BALANCE RESISTOR. OUT OF TOLERANCE. BOS/BOS - FLT 361 - ABORTED TAKEOFF, NR 2 ENGINE EGT WAS ERRATIC. THE NR 2 ENGINE EGT GAUGE STOPS AT APPROXIMATELY 350 DEGREES WHEN TAKEOFF POWER WAS APPLIED.

All 52: https://openairdocs.org/model/douglas-dc-9-21/reports.md

## STCs that may be installed (OpenAirDocs) (207, first 50)

Approved for this model: the STC's model list names it on its data sheet, or a series that includes it. In force first, then newest. The registry doesn't record which STCs an aircraft has.

- [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 ST00030IB](https://openairdocs.org/stc/ST00030IB): Installation of Test Tech ELT. APTOZ EHF
- [STC ST09181AC](https://openairdocs.org/stc/ST09181AC): Installation of main landing gear spotlights. The Boeing Company
- [STC ST03885AT](https://openairdocs.org/stc/ST03885AT): Installation of an Avionica, Inc. avCM Cellular Module. Aircraft Systems and Manufacturing Inc
- [STC SA2040NM](https://openairdocs.org/stc/SA2040NM): Installation of closet and windscreen. Safran Cabin Inc
- [STC SA3469NM](https://openairdocs.org/stc/SA3469NM): Installation of Closet/Stowage Compartments/Coat Compartment/ Coatroom. Safran Cabin Inc
- [STC SA3494NM](https://openairdocs.org/stc/SA3494NM): Installation of auxiliary galley. Safran Cabin Inc. Lists DC-9 Series
- [STC SA3165NM](https://openairdocs.org/stc/SA3165NM): Installation of Floor Proximity Emergency Escape Path Marking System. Bruce Aerospace Inc
- [STC ST00092LA](https://openairdocs.org/stc/ST00092LA): Instalation of interior fluorescent cabin lighting system. Bruce Aerospace Inc
- [STC ST00069AT](https://openairdocs.org/stc/ST00069AT): Installation of a Fairchild Digital or Sundstrand Universal expanded parameters digital flight data recorder. Acron Aviation Inc
- [STC ST01518NY](https://openairdocs.org/stc/ST01518NY): Installation of Flight Systems Cabin Surveillance System (CSS). Acron Aviation Inc
- [STC ST02472AT](https://openairdocs.org/stc/ST02472AT): Installation of a mini Quick Access Recorder (QAR) model MKI, MKII, or MKIII. Aircraft Systems and Manufacturing Inc
- [STC ST00984CH](https://openairdocs.org/stc/ST00984CH): Installation of Rockwell Collins FPI-955 Electronic Horizontal Situation Indicators (EHSI). Amphenol Cable and Interconnect Technologies Inc
- [STC ST01017CH](https://openairdocs.org/stc/ST01017CH): Installation of an AlliedSignal CAS-81 TCAS II System with dual AlliedSignal Mode S Transponders. Amphenol Cable and Interconnect Technologies Inc
- [STC ST01019CH](https://openairdocs.org/stc/ST01019CH): Installation of a Rockwell Collins GNLS-910 GPS Flight Management System. Amphenol Cable and Interconnect Technologies Inc
- [STC ST01167CH](https://openairdocs.org/stc/ST01167CH): Installation of an AlliedSignal MK-VII Enhanced Ground Proximity Warning System. Amphenol Cable and Interconnect Technologies, Inc
- [STC ST01404CH](https://openairdocs.org/stc/ST01404CH): Installation of Universal Avionics System Corporation Multi-Function Display. Amphenol Cable and Interconnect Technologies, Inc
- [STC ST01818CH](https://openairdocs.org/stc/ST01818CH): Installation of a Honeywell Enhanced Ground Proximity Warning System. Amphenol Cable and Interconnect Technologies, Inc
- [STC ST01887CH](https://openairdocs.org/stc/ST01887CH): Installation of GPS antenna provisions. Amphenol Cable and Interconnect Technologies, Inc
- [STC ST01936WI](https://openairdocs.org/stc/ST01936WI): Installation of LED lights. AeroLED's Holdings LLC
- [STC ST02876AT](https://openairdocs.org/stc/ST02876AT): Installation of a Free Flight Model 2101 I/O Approach Plus Global Positioning System (GPS), Universal Model MFD 640 Multi-function Display (MFD), and Provisions for an Aviation Communication & Surveillance Systems (ACSS) Terrain & Traffic Collision Avoidance System (TTCAS). Woven Electronics, LLC
- [STC ST00098IB](https://openairdocs.org/stc/ST00098IB): Introduction of ADS-B Out. STC Twenty One Limited
- [STC ST02896AT](https://openairdocs.org/stc/ST02896AT): Installation of a Kannad Model 406-AF Emergency Locator Transmittter (ELT). Woven Electronics LLC
- [STC ST03735AT](https://openairdocs.org/stc/ST03735AT): Installation of a LED Indirect Cabin Lighting System. Woven Electronics LLC
- [STC SA2534SW-D](https://openairdocs.org/stc/SA2534SW-D): Replacement of Switch assembly Int'l Inflatables Co. P/N 68748, with DME Corp. P/N L-140 in emergency evacuation slide lighting system. Astronics Luminescent Systems Inc. Lists DC-9 Series
- [STC SA2539SW-D](https://openairdocs.org/stc/SA2539SW-D): Replacement of light assembly, International Inflatables Co. P/N68555-1 with DME Corp. EL-104, EL-104A, and EL-104B in emergency slide lighting system. Astronics Luminescent Systems Inc. Lists DC-9 Series
- [STC SA863EA](https://openairdocs.org/stc/SA863EA): Incorporation of DME Corporation emergency evacuation slide lighting system. Astronics Luminescent Systems Inc. Lists DC-9 Series
- [STC ST02929AT](https://openairdocs.org/stc/ST02929AT): Installation of an Artex Model C406-1 Emergency Locator Transmitter (ELT). Woven Electronics LLC
- [STC ST03838AT](https://openairdocs.org/stc/ST03838AT): Installation of an Universal Avionics Application Server Unit (ASU) System Class II Electronic Flight Bag (EFB). Technical Aero Services Inc
- [STC SA1220NW](https://openairdocs.org/stc/SA1220NW): Installation of Universal flight data recorder. Honeywell International Inc
- [STC SA5920NM](https://openairdocs.org/stc/SA5920NM): Installation of 980-4100-HQUS Flight Data Recorder and Penny and Giles Quick Access Recorder in accordance with Document 755-3024, Rev. New-1, or later FAA approved revision. Honeywell International Inc
- [STC ST00074AT](https://openairdocs.org/stc/ST00074AT): Installation of a Bendix/King Mode S transponder. Honeywell International Inc
- [STC ST00075AT](https://openairdocs.org/stc/ST00075AT): Installation of a CAS-81 TCAS II. Honeywell International Inc
- [STC ST00791SE](https://openairdocs.org/stc/ST00791SE): Installation of a solid state cockpit voice recorder. Honeywell International Inc
- [STC ST01828AT](https://openairdocs.org/stc/ST01828AT): Installation of a RTA-83A VHF Communication System. Honeywell International Inc
- [STC SA3748SW](https://openairdocs.org/stc/SA3748SW): Installation of heat exchanger assembly (P/N 184060). Honeywell International Inc
- [STC SA4398SW](https://openairdocs.org/stc/SA4398SW): Modification of air to air heat exchanger (P/N 179450-2-2 or194110-1). Honeywell International Inc. Lists DC-9 Series
- [STC SA640NW](https://openairdocs.org/stc/SA640NW): Installation of contemporary deep rack interior. Safran Cabin Inc. Lists DC-9 Series
- [STC ST00939LA](https://openairdocs.org/stc/ST00939LA): Installation of passenger entertainment system. Burrana Inc. Lists DC-9 Series
- [STC ST03574AT](https://openairdocs.org/stc/ST03574AT): Installation of a Talon Aerospace Anti-Collision Light. Aaxico Technical Services Inc
- [STC ST04002AT](https://openairdocs.org/stc/ST04002AT): Installation of a Talon LED Replacement Wing and Tail Mounted Anti-Collision Lights. Aaxico Technical Services Inc
- [STC ST04177AT](https://openairdocs.org/stc/ST04177AT): Installation of a Talon Aerospace LED Replacement General Purpose Lamps. Aaxico Technical Services Inc
- [STC SA2410NM](https://openairdocs.org/stc/SA2410NM): Installation of a Hughes-Avicom Audio Tape Reproducer. Burrana Inc. Lists DC-9 Series
- [STC SA2169CE](https://openairdocs.org/stc/SA2169CE): Installation of King KNS 660 flight management system. Honeywell International Inc
- [STC SA4817NM](https://openairdocs.org/stc/SA4817NM): Installation of standard windshear systems. Honeywell International Inc
- [STC SA8047NM](https://openairdocs.org/stc/SA8047NM): Installation of Honeywell Digital air data computer (DADC). Honeywell International Inc
- [STC ST04340NY](https://openairdocs.org/stc/ST04340NY): Installation of TCAS 7.1 (ACAS II) upgrade of Prior Existing TCAS 7.0. Scandinavian Avionics Design ApS
- [STC SA8339SW](https://openairdocs.org/stc/SA8339SW): Installation of a fuselage nose radome shell. The NORDAM Group LLC
- [STC ST02636LA](https://openairdocs.org/stc/ST02636LA): Modification to upgrade the existing XS-950 Mode S Transponder system to add ADS-B Out. Aviation Communication and Surveillance Systems (ACSS) LLC
- [STC SA3327NM](https://openairdocs.org/stc/SA3327NM): Installation of Kevlar composite Aft Tip Fairing for vertical stabilizer. Aviation Technical Services

All 207: https://openairdocs.org/model/douglas-dc-9-21/stcs.md

## The same model under other registry codes

Amateur-built copies and renamed makers get their own codes.

- [Mcdonnell Douglas DC-9-21](https://openairdocs.org/model/mcdonnell-douglas-dc-9-21): 0 registered aircraft, registry code 302205C

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