# MD Helicopters 500N

- Type: Aircraft model (FAA registry)
- Registry code: 3030001
- Manufacturer (registry): MD HELICOPTERS INC
- Model: 500N
- Aircraft type: Rotorcraft
- Category: Rotorcraft
- Engines: 1 · Turbo-shaft
- Seats: 4
- Weight class: 12,500 to 19,999 lb
- Certification: Type certificated
- Data sheet: [TCDS H3WE](https://openairdocs.org/tcds/H3WE) (OpenAirDocs)
- Holder: MD Helicopters LLC
- Registered aircraft: 13
- Page: https://openairdocs.org/model/md-helicopters-500n

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 2026-21-05](https://openairdocs.org/ad/2026-21-05): Engine/transmission coupling · MD Helicopters 369D, 369E, 369F and 3 more. Effective Nov 27, 2026
- [AD 2026-19-01](https://openairdocs.org/ad/2026-19-01): Rotorcraft flight control · MD Helicopters 369, 369 (Army YOH-6A), 369A and 11 more. Effective Oct 20, 2026
- [AD 2025-17-11](https://openairdocs.org/ad/2025-17-11): tail rotor control system · MD Helicopters 369 (Army YOH-6A), 369A (Army OH-6A), 369D and 9 more. Effective Oct 10, 2025
- [AD 2024-20-07](https://openairdocs.org/ad/2024-20-07): Emergency Equipment; Emergency Flotation Section · Apical Emergency Float Kit, P/N 20498 (STC SR00780LA or 12 others). Effective Dec 5, 2024
- [AD 2023-11-07](https://openairdocs.org/ad/2023-11-07): Ground Proximity System · Airbus Helicopters 47, 206, 210 and 237 more. Effective Jun 22, 2023
- [AD 2021-22-11](https://openairdocs.org/ad/2021-22-11): Tail Rotor Control System · MD Helicopters 369D, 369E, 369F and 7 more. Effective Jan 10, 2022
- [AD 2020-18-20](https://openairdocs.org/ad/2020-18-20): Main Rotor Blade · MD Helicopters 369A, 369D, 369E and 7 more. Effective Oct 28, 2020
- [AD 2020-11-07](https://openairdocs.org/ad/2020-11-07): Main Rotor System · MD Helicopters 369D, 369E, 369FF and 6 more. Effective Jun 30, 2020
- [AD 2019-05-04](https://openairdocs.org/ad/2019-05-04): Main Rotor Blade · MD Helicopters 369A, 369D, 369E and 7 more. Effective Apr 17, 2019
- [AD 2016-05-09](https://openairdocs.org/ad/2016-05-09): Fuel Quantity Indicating System · MD Helicopters 369A, 369D, 369E and 7 more. Effective Apr 15, 2016
- [AD 2016-04-15](https://openairdocs.org/ad/2016-04-15): Main Rotor Blades · MD Helicopters 369A, 369D, 369E and 6 more. Effective Mar 31, 2016
- [AD 2016-01-19](https://openairdocs.org/ad/2016-01-19): Rotorcraft Tail Boom · MD Helicopters 500N and 600N. Effective Feb 25, 2016
- [AD 2013-03-03](https://openairdocs.org/ad/2013-03-03): Tail rotor blades · MD Helicopters 500N, 600N and MD900. Effective Mar 15, 2013
- [AD 2008-22-52](https://openairdocs.org/ad/2008-22-52): Yaw Stability Augmentation System · MD Helicopters 500N and 600N. Effective Dec 15, 2008
- [AD 2007-12-23](https://openairdocs.org/ad/2007-12-23): Landing gear fairing support assembly · MD Helicopters 369A, 369D, 369E and 7 more. Effective Jul 19, 2007
- [AD 2005-21-02](https://openairdocs.org/ad/2005-21-02): Main rotor blade (blade) · Main rotor blades P/N 500P2300-501/503/505 (Helicopter Technology STC SR01050LA or 2 others). Effective Nov 1, 2005
- [AD 2004-20-08](https://openairdocs.org/ad/2004-20-08): Forward and center thruster control cable assembly connector (connector) · MD Helicopters 500N and 600N. Effective Oct 21, 2004
- [AD 2002-20-05](https://openairdocs.org/ad/2002-20-05): Rescue hoists · Agusta A109, A109A, A109A II and 31 more. Effective Nov 7, 2002
- [AD 2000-25-52](https://openairdocs.org/ad/2000-25-52): Main rotor blade · MD Helicopters 369A, 369D, 369E and 6 more. Effective Feb 6, 2001
- [AD 2000-08-22](https://openairdocs.org/ad/2000-08-22): Turbine Outlet Temperature (TOT) Indicating System · MD Helicopters 369D, 369E, 500N and 1 more. Effective May 22, 2000
- [AD 99-25-08](https://openairdocs.org/ad/99-25-08): Thruster Control Cable Conduit Cap · MD Helicopters 500N and 600N. Effective Mar 1, 2000
- [AD 99-20-12](https://openairdocs.org/ad/99-20-12): Bracket P/N 369F5190-1 · MD Helicopters 369D, 369E, 369FF and 2 more. Effective Nov 4, 1999
- [AD 99-08-07](https://openairdocs.org/ad/99-08-07): Engine Control And Warning System · MD Helicopters 369E, 369FF, 500N and 1 more. Effective Apr 21, 1999
- [AD 99-04-12](https://openairdocs.org/ad/99-04-12): Input Shaft Coupling Assembly · MD Helicopters 369D, 369E, 369FF and 3 more. Effective Mar 23, 1999
- [AD 98-21-12](https://openairdocs.org/ad/98-21-12): Overrunning Clutch Retainer Inspection · MD Helicopters 369D, 369E, 369FF and 1 more. Effective Oct 22, 1998
- [AD 98-14-03](https://openairdocs.org/ad/98-14-03): Transponders · Cessna 172, 172A, 172B and 230 more. Effective Aug 16, 1998
- [AD 98-15-26](https://openairdocs.org/ad/98-15-26): Main Rotor Blade Cracking Inspection · MD Helicopters 369A, 369D, 369E and 8 more. Effective Aug 3, 1998
- [AD 98-09-02](https://openairdocs.org/ad/98-09-02): Overrunning Clutch Assembly Outer Race · MD Helicopters 369, 369A, 369D and 8 more. Effective May 6, 1998
- [AD 97-15-08](https://openairdocs.org/ad/97-15-08): Transmission Output Drive Gear · MD Helicopters 369D, 369E, 369F and 2 more. Effective Aug 4, 1997
- [AD 96-10-09](https://openairdocs.org/ad/96-10-09): Blade Root End Crack Inspection · MD Helicopters 369, 369A, 369D and 8 more. Effective May 29, 1996
- [AD 96-08-03](https://openairdocs.org/ad/96-08-03): Hardpoint Assemblies · Hardpoints (Flight Trails Helicopters STC SH6080NM). Effective May 20, 1996

Historical (superseded or no longer in force):

- [AD 2024-23-06](https://openairdocs.org/ad/2024-23-06) (historical): Rotorcraft Flight Control · MD Helicopters 369, 369A, 369D and 11 more. Effective Dec 24, 2024
- [AD 2021-23-13](https://openairdocs.org/ad/2021-23-13) (historical): Ground Proximity System · Airbus Helicopters K-225, K-190A, K-240 and 237 more. Effective Dec 9, 2021
- [AD 2008-18-52](https://openairdocs.org/ad/2008-18-52) (historical): Prevent loss of yaw control and subsequent loss of control of the helicopter · MD Helicopter 500N, 600N and MD900
- [AD 2008-18-51](https://openairdocs.org/ad/2008-18-51) (historical): Vertical Stabilizer Control System (VSCS) · MD Helicopter 500N, 600N and MD900
- [AD 2000-24-51](https://openairdocs.org/ad/2000-24-51) (historical): Blade Spar · MD Helicopter 369A, 369D, 369E and 6 more

## Information bulletins (advisory) (3)

- [SAIB AIR-21-19R1](https://openairdocs.org/saib/AIR-21-19R1): AERIAL TOW EQUIPMENT, Side Pull Hook. Issued Nov 29, 2021
- [SAIB AIR-21-19](https://openairdocs.org/saib/AIR-21-19) (historical): AERIAL TOW EQUIPMENT, Side Pull Hook. Issued Nov 29, 2021
- [SAIB SW-12-45](https://openairdocs.org/saib/SW-12-45): Garmin Model 400W/500W Series GPS-WAAS Navigation System. Issued Oct 3, 2012

## Registered aircraft (13)

- [N103CG](https://openairdocs.org/aircraft/N103CG): [City Of Burbank](https://openairdocs.org/faa-owner/CITY%20OF%20BURBANK), [Burbank, CA](https://openairdocs.org/faa-place/CA/Burbank), built 2006, S/N LN102
- [N33C](https://openairdocs.org/aircraft/N33C): [Sunshine 123 LLC](https://openairdocs.org/faa-owner/SUNSHINE%20123%20LLC), [Wilmington, DE](https://openairdocs.org/faa-place/DE/Wilmington), built 2018, S/N LN113
- [N515TH](https://openairdocs.org/aircraft/N515TH): [Rick'S Custom Fencing And Decking Inc](https://openairdocs.org/faa-owner/RICK'S%20CUSTOM%20FENCING%20AND%20DECKING%20INC), [Hillsboro, OR](https://openairdocs.org/faa-place/OR/Hillsboro), built 2002, S/N LN099
- [N520AP](https://openairdocs.org/aircraft/N520AP): [Ln095 1vc Trustee](https://openairdocs.org/faa-owner/LN095%201VC%20TRUSTEE), [Wilmington, DE](https://openairdocs.org/faa-place/DE/Wilmington), built 2001, S/N LN095
- [N520PD](https://openairdocs.org/aircraft/N520PD): [City Of Glendale Police Department](https://openairdocs.org/faa-owner/CITY%20OF%20GLENDALE%20POLICE%20DEPARTMENT), [Glendale, CA](https://openairdocs.org/faa-place/CA/Glendale), built 2014, S/N LN111
- [N520VC](https://openairdocs.org/aircraft/N520VC): [Volusia County Mosquito Control](https://openairdocs.org/faa-owner/VOLUSIA%20COUNTY%20MOSQUITO%20CONTROL), [New Smyrna Beach, FL](https://openairdocs.org/faa-place/FL/New%20Smyrna%20Beach), built 2015, S/N LN112
- [N523HB](https://openairdocs.org/aircraft/N523HB): [Crg2 LLC](https://openairdocs.org/faa-owner/CRG2%20LLC), [Lees Summit, MO](https://openairdocs.org/faa-place/MO/Lees%20Summit), built 2007, S/N LN105
- [N70512](https://openairdocs.org/aircraft/N70512): [Bank Of Utah Trustee](https://openairdocs.org/faa-owner/BANK%20OF%20UTAH%20TRUSTEE), [Salt Lake City, UT](https://openairdocs.org/faa-place/UT/Salt%20Lake%20City), built 2000, S/N LN092
- [N910PG](https://openairdocs.org/aircraft/N910PG): [Prince Georges County](https://openairdocs.org/faa-owner/PRINCE%20GEORGES%20COUNTY), [College Park, MD](https://openairdocs.org/faa-place/MD/College%20Park), built 2000, S/N LN090
- [N911PG](https://openairdocs.org/aircraft/N911PG): [Prince Georges County](https://openairdocs.org/faa-owner/PRINCE%20GEORGES%20COUNTY), [College Park, MD](https://openairdocs.org/faa-place/MD/College%20Park), built 2000, S/N LN091
- [N912PG](https://openairdocs.org/aircraft/N912PG): [Prince Georges County Police Department](https://openairdocs.org/faa-owner/PRINCE%20GEORGES%20COUNTY%20POLICE%20DEPARTMENT), [College Park, MD](https://openairdocs.org/faa-place/MD/College%20Park), S/N LN104
- [N913PG](https://openairdocs.org/aircraft/N913PG): [Prince Georges County Police Dept](https://openairdocs.org/faa-owner/PRINCE%20GEORGES%20COUNTY%20POLICE%20DEPT), [College Park, MD](https://openairdocs.org/faa-place/MD/College%20Park), built 2008, S/N LN108
- [N977WF](https://openairdocs.org/aircraft/N977WF): [Forest View Helicopters LLC](https://openairdocs.org/faa-owner/FOREST%20VIEW%20HELICOPTERS%20LLC), [Marienville, PA](https://openairdocs.org/faa-place/PA/Marienville), built 2013, S/N LN110

## NTSB investigations (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB NYC06TA190](https://openairdocs.org/ntsb/NYC06TA190), Aug 2, 2006: MD Helicopter 500N (N520AP), Louisville, KY, substantial damage. Probable cause: The pilot's failure to maintain control of the helicopter and the flight instructor's inadequate supervision, which resulted in a hard landing and subsequent rollover.

## FAA accident and incident reports (3)

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 20190413016879I](https://openairdocs.org/incident/20190413016879I), Apr 13, 2019: Md Helicopters Inc 500N (N523HB), Santa Ana, CA, No damage. Performing right hand orbits over a location PIC [privacy data omitted] came out of the orbit and felt the right anti-torque pedal was stuck. It was diagnosed…
- [Incident 20111202027739I](https://openairdocs.org/incident/20111202027739I), Dec 2, 2011: Md Helicopters Inc 500N (N70512), Mesa, AZ, Minor damage. Factory instructional training flight (recurrent). On third straight in full down autorotation, right rear landing gear strut failed at pivoting bolt hole,…
- [Accident 20060802017559A](https://openairdocs.org/incident/20060802017559A), Aug 2, 2006: Hughes 500N (N520AP), Louisville, KY, Substantial damage. (-23) Helicopter crashed resulting in one pilot sustaining fractured vertebra and causing substantial damage to the aircraft. Pilot's statements indicate that…

## Service difficulty reports (103, newest 50)

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

- [SDR 2023FA0000627](https://openairdocs.org/sdr/2023FA0000627), Jun 28, 2023: BLADE. UNKNOWN. IN RNGARDS TO THE MD 500N HOLICOPTER, LHLS IS THE SECOND LIMO THAT I HAVE THE SAME ISSUE WITH THE NOTAR FAN BLADE ASSEMBLIES HAVING A STRANGO WEAR PALLERN ON TH
- [SDR 2023FA0000626](https://openairdocs.org/sdr/2023FA0000626), Jun 28, 2023: BLADE. UNKNOWN. THO 1.1O500N HERICOPLER HAS A 13 BLADED ANTI IOFQUO FAN (NOTAR FAN) INSTEAD DO TRND1TLONAL LAIL ROLET ASSY. THE NOTAR FAN NSSY'S PIN IS 500N5300-7. THO PIN OF L
- [SDR 2006FA0000552](https://openairdocs.org/sdr/2006FA0000552), May 13, 2006: CABLE. BROKEN. PILOT WAS PRACTICING AUTOROTATION AND FELT A CHANGE IN THE PEDALS. AFTER TOUCHDOWN, HE ATTEMPTED TO HOVER BY RAISING THE COLLECTIVE, AND THE HELICOPTER BEGAN TO
- [SDR 2006FA0000509](https://openairdocs.org/sdr/2006FA0000509), May 13, 2006: CABLE. SEVERED. DURING PRACTICE AUTOROTATIONS, PILOT FELT A CHANGE IN THE ANTI-TORQUE PEDALS. AFTER TOUCHDOWN HE ATTEMPTED TO RAISE THE COLLECTIVE AND THE HELICOPTER BEGIN TO S
- [SDR 2006FA0000115](https://openairdocs.org/sdr/2006FA0000115), Oct 6, 2005: COMBUST CHAMBER. CRACKED. DURING AN INSPECTION FOR HIGH TOT THE OUTER COMBUSTION CAN WAS FOUND TO BE CRACKED IN THE LEFT (ARM PIT). (K)
- [SDR 2004FA0000733](https://openairdocs.org/sdr/2004FA0000733), Aug 11, 2004: MOUNT. OUT OF POSITION. AIRCRAFT FOUND TO HAVE CONTACT WITH FAN CONTROL ROD AND FAN DRIVESHAFT. WHICH MAY HAVE BEEN THE CAUSE OF HIGH VIBRATION IN AIRFRAME. MFG CALLED TO CHECK THE ALI
- [SDR 2004FA0000722](https://openairdocs.org/sdr/2004FA0000722), Jul 15, 2004: MOUNT. OUT OF ADJUST. AIRCRAFT OVERCOME WITH SEVERE VIBRATION ON THROTTLE ROLL UP FROM GROUND IDLE TO FLIGHT IDLE. FOUND FAN CONTROL ROD MADE CONTACT INSIDE FAN DRIVESHAFT. UPON FURT
- [SDR 2004FA0000721](https://openairdocs.org/sdr/2004FA0000721), Jul 15, 2004: MOUNT. OUT OF POSITION. AIRCRAFT FOUND TO HAVE CONTACT WITH FAN CONTROL ROD AND FAN DRIVESHAFT, WHICH MAY HAVE BEEN THE CAUSE OF HIGH VIBRATION IN AIRFRAME. MFG CALLED TO CHECK THE ALI
- [SDR GO42004F00000](https://openairdocs.org/sdr/GO42004F00000), Apr 12, 2004: CONTROL CABLE. BROKEN. DURING DAILY INSP, THE THRUSTER ASSY SYSTEM WAS OPERATED TO CHECK THE OPERATION AND SMOOTHNESS OF THIS SYSTEM. A LOUD NOISE WAS HEARD AND THE THRUSTER CONE WAS 
- [SDR CA031017004](https://openairdocs.org/sdr/CA031017004), Oct 4, 2003: FUEL CONTROL. FAILED. (CAN) AFTER LANDING, THROTTLE WAS SNAP ROLLED TO IDLE. N2 WAS NR IMMEDIATELY INCREASED TO 105 PERCENT AND STABILIZED. ENGINE WAS SHUT DOWN BY ROLLING THROTTLE T
- [SDR CA030729016](https://openairdocs.org/sdr/CA030729016), Jul 10, 2003: CONTROL CABLE. FAILED. (CAN) AT PREFLT, PILOT REPORTED A 'BINDING' AT EXTREME RT PEDAL. MAINT DISCONNECTED SECTIONS OF SYS & COULDN`T REPEAT. DAYS LATER PILOT REPORTED SIMILAR BINDING
- [SDR CA030312016](https://openairdocs.org/sdr/CA030312016), Feb 12, 2003: BEARING. MAKING METAL. (CAN) DURING A FLIGHT THE ENGINE CHIP LIGHT ILLUMINATED, THE PILOT LANDED AND THE LOWER CHIP PLUG WAS INSPECTED AND HAD SHINY PARTICLES ON IT. THE AIRCRAFT WAS 
- [SDR AUS20020748](https://openairdocs.org/sdr/AUS20020748), Jul 10, 2002: STRUT. CRACKED. (AUS) LT MAIN LANDING GEAR STRUT CRACKED FROM RIVET HOLE. CRACK LENGTH 9.525MM (0.375IN).
- [SDR CA011211017](https://openairdocs.org/sdr/CA011211017), Dec 4, 2001: STRUT. CRACKED. (CAN) CRACK FOUND ON UPPER PART OF STRUT AROUND THE BRACE ATTACHMENT HOLE.
- [SDR CA011211015](https://openairdocs.org/sdr/CA011211015), Dec 4, 2001: STRUT. CRACKED. (CAN) CRACK FOUND ON UPPER PART OF STRUT AROUND THE BRACE ATTACHMENT HOLE.
- [SDR CA011211014](https://openairdocs.org/sdr/CA011211014), Dec 4, 2001: STRUT. CRACKED. (CAN) CRACK FOUND ON UPPER PART OF STRUT AROUND THE BRACE ATTACHMENT HOLE.
- [SDR CA011211013](https://openairdocs.org/sdr/CA011211013), Dec 4, 2001: STRUT. CRACKED. (CAN) CRACK FOUND ON UPPER PART OF STRUT AROUND THE BRACE ATTACHMENT HOLE.
- [SDR CA011211016](https://openairdocs.org/sdr/CA011211016), Nov 23, 2001: STRUT. CRACKED. (CAN) CRACK FOUND ON UPPER PART OF STRUT AROUND THE BRACE ATTACHMENT HOLE.
- [SDR AUS20010762](https://openairdocs.org/sdr/AUS20010762), Jul 12, 2001: OIL SYSTEM. BLOCKED. (AUS) NR 6 AND NR 7 BEARING OIL SCAVENGE PORT PARTIALLY BLOCKED BY CARBON DEPOSITS. OIL TYPE HAD BEEN CHANGED FROM MOBIL 254 TO MOBIL 291.
- [SDR 20001106SH085](https://openairdocs.org/sdr/20001106SH085), Oct 15, 2000: CONTROL ROD. CHAFED. PILOT REPORTED, DURING THROTTLE ADVANCE ON RUN-UP, A LOUD RUMBLING NOISE AND SEVERE VIBRATION STARTED ABRUPTLY AS TORQUE APPROACHED 40 PERCENT TORQUE. INSP OF A
- [SDR 20001108SH027](https://openairdocs.org/sdr/20001108SH027), Oct 13, 2000: GEAR. SPALLED. MAIN ROTOR CHIP DETECTORS PICKING UP MAJOR METAL. OPENED GEARBOX AND INSPECTED. FOUND SPALLING OF ALL GEARS. SUBMITTER SUGGESTED OIL NOT LUBRICATING UNDER LOADS
- [SDR 20001103SH001](https://openairdocs.org/sdr/20001103SH001), Oct 13, 2000: MAST. DAMAGED. FOUND PAINT SEALANT INSIDE MAIN ROTOR MAST TUBE BLISTERED AND FALLING INTO MAIN ROTOR TRANSMISSION GEARBOX. APPEARED THAT MAIN ROTOR TRANSMISSION OIL MOBILE SHC
- [SDR 20001102SH038](https://openairdocs.org/sdr/20001102SH038), Oct 13, 2000: MAST. DAMAGED. FOUND PAINT SEALANT INSIDE MAST TUBE BLISTERED AND FALLING INTO M/R TRANSMISSION GEARBOX. APPEARED THAT M/R TRANSMISSION OIL MOBILE SHC 626 IS NOT COMPATIBLE WI
- [SDR 20001102SH037](https://openairdocs.org/sdr/20001102SH037), Oct 13, 2000: MAST. DAMAGED. FOUND PAINT SEALANT INSIDE MAIN ROTOR MAST TUBE BLISTERED AND FALLING INTO M/R TRANSMISSION GEARBOX. APPEARED THAT M/R TRANSMISSION OIL MOBILE SHC 626 IS NOT CO
- [SDR 20001102SH036](https://openairdocs.org/sdr/20001102SH036), Oct 13, 2000: MAST. DAMAGED. FOUND PAINT SEALANT INSIDE MAIN ROTOR MAST TUBE BLISTERED AND FALLING INTO M/R TRANSMISSION GEARBOX. APPEARED THAT M/R TRANSMISSION OIL MOBIL SHC 626 IS NOT COM
- [SDR 20001102SH035](https://openairdocs.org/sdr/20001102SH035), Oct 13, 2000: MAST. DAMAGED. FOUND PAINT SEALANT INSIDE MAIN ROTOR MAST TUBE BLISTERED AND FALLING INTO M/R TRANSMISSION GEARBOX. APPEARED THAT M/R TRANSMISSION OIL MOBILE SHC 626 IS NOT CO
- [SDR 20001102SH034](https://openairdocs.org/sdr/20001102SH034), Oct 13, 2000: MAST. DAMAGED. FOUND PAINT SEALANT INSIDE M/R MAST TUBE BLISTERED AND FALLING INTO M/R TRANSMISSION GEARBOX. APPEARED THAT M/R TRANSMISSION OIL MOBILE SHC 626 IS NOT COMPATIBL
- [SDR 20001102SH033](https://openairdocs.org/sdr/20001102SH033), Oct 13, 2000: MAST. DAMAGED. FOUND PAINT SEALANT INSIDE MAIN ROTOR MAST TUBE BLISTERED AND FALLING INTO M/R TRANSMISSION GEARBOX. APPEARED THAT M/R TRANSMISSION OIL MOBILE SHC 626 IS NOT CO
- [SDR CA010219007](https://openairdocs.org/sdr/CA010219007), Sep 20, 2000: TUBE. LEAKING. (CAN) PILOT REPORTED INCREASED START TEMPERATURE. ON RUN-UP IT WAS DISCOVERED THAT THE LARGE AIR LINE BETWEEN THE ENGINE COMPRESSOR AND THE FIREWALL WAS LEAKING
- [SDR 20001017SH022](https://openairdocs.org/sdr/20001017SH022), Sep 18, 2000: NUT. LOOSE. AT ACTT: 23.5 HOURS, THE UNILOCK, PN 369A7010501 SN 024598-5326, WAS INSTALLED IN NEW CONDITION TO REPLACE A LEAKING UNILOCK. AFTER 23.6 HRS OF OPERATION, PILOT
- [SDR CA000920005](https://openairdocs.org/sdr/CA000920005), Aug 11, 2000: TURBINE. CARBONED. (CAN) DURING FLIGHT, A LOSS OF OIL PRESSURE AND TORQUE INDICATION WAS NOTED. AN IMMEDIATE LANDING WAS PERFORMED AND THE ENGINE WAS SECURED. THE ENGINE OIL LEVEL
- [SDR CA000110025](https://openairdocs.org/sdr/CA000110025), Dec 15, 1999: STRUT. CRACKED. (CAN) LEFT REAR LANDING GEAR STRUT STRUCTURALLY FAILED. IT APPEARS THAT THE CRACK BEGAN AT RIVET HOLE FOR STRUT FAIRING ATTACHMENT BRACKET.
- [SDR 2000ZZZX661](https://openairdocs.org/sdr/2000ZZZX661), Dec 9, 1999: GOVERNOR. FAILED. GOVERNOR FAILURE, UNIT BECOMES ERRATIC IN OPERATION. WILL NOT HOLD ENGINE RPM. SUBMITTER STATED EXPERIENCED THREE SUCH FAILURES THIS YEAR ON FLEET. (X)
- [SDR 99ZZZX4701](https://openairdocs.org/sdr/99ZZZX4701), Oct 25, 1999: CABLES. FRACTURED. DURING POST-CRASH EXAMINATION OF THE ANTI-TORQUE CONTROL SYSTEM, FRACTURES WERE FOUND OF THE PUSH/PULL TYPE THRUSTER CONTROL CABLES P/N 500N7201-5 AND -37. THE 
- [SDR CA990630010](https://openairdocs.org/sdr/CA990630010), Jun 4, 1999: BLADE. DAMAGED. (CAN) UPON INSPECTION, A VOID WAS DETECTED IN THE GRIP PLATE THAT IS BEYOND THE MANUFACTURER'S SET FORTH REPAIRABLE LIMITS AND ALSO OUTSIDE THE PARAMETERS OFADS
- [SDR 99ZZZX2014](https://openairdocs.org/sdr/99ZZZX2014), Apr 25, 1999: SWITCH. FAILED. PILOT TRIM SWITCH RUN-A-WAY AFT.
- [SDR 99ZZZX2358](https://openairdocs.org/sdr/99ZZZX2358), Feb 1, 1999: BEARING. FAILED. PILOT FOUND GOVERNOR SWAGING ABOVE LIMITS FOR SAFE FLIGHT. ENIGNE SURGING 20 PSI TORQUE AND 5 PERCENT N2. UPON REMOVAL OF GOVERNOR, FOUND DRIVE SHAFT LOCKED-UP.
- [SDR 98ZZZX2241](https://openairdocs.org/sdr/98ZZZX2241), May 27, 1998: ROD. CRACKED. INSPECTION FOUND GAS PRODUCER INTERCONNECT TUBE WITH CRACKS, 2 EACH, 180 DEGREES APART AT SHORT END.
- [SDR 98ZZZX2109](https://openairdocs.org/sdr/98ZZZX2109), May 22, 1998: TORQUE TUBE. MISDRILLED. COLLECTIVE TORQUE TUBE HAS BOLT HOLES NOT DRILLED TO PROPER SIZE FOR GEARBOX MOUNT BOLTS TO BE PASSED THROUGH. TWO EACH PARTS FROM FACTORY BOTH UNDERSIZED HOLES
- [SDR 98ZZZX2108](https://openairdocs.org/sdr/98ZZZX2108), May 22, 1998: TORQUE TUBE. MISDRILLED. COLLECTIVE TORQUE TUBE HAS BOLT HOLES NOT DRILLED TO PROPER SIZE FOR GEARBOX MOUNT BOLTS TO BE PASSED THROUGH. TWO EACH PARTS FROM FACTORY BOTH UNDERSIZED HOLES
- [SDR 98ZZZX2107](https://openairdocs.org/sdr/98ZZZX2107), May 22, 1998: PUSH ROD. DAMAGED. DURING INSPECTION PRIOR TO INSTALLATION, GREASE SEALS ON ROD END WERE FOUND TO HAVE DENTS AND DEFORMED FROM FACTORY BUILD-UP.
- [SDR 98ZZZX1833](https://openairdocs.org/sdr/98ZZZX1833), Jan 29, 1998: TRIM SWITCH. FAILED. CYCLIC TRIM SWITCH RUNS AWAY TO RIGHT SIDE.
- [SDR 98ZZZX177](https://openairdocs.org/sdr/98ZZZX177), Dec 16, 1997: BELLCRANK. BINDING. FOUND ON ACCEPTANCE INSPECTION THAT BELLCRANK HAS BOTH PIVOT BEARINGS PRE-LOADED TO A POINT OF NO ROTATION.
- [SDR 98ZZZX176](https://openairdocs.org/sdr/98ZZZX176), Dec 16, 1997: BELLCRANK. BINDING. FOUND ON ACCEPTANCE INSPECTION THAT BELLCRANK HAS BOTH PIVOT BEARINGS PRE-LOADED TO A POINT BEARING WILL NOT ROTATE FOR INSTALLATION.
- [SDR 98ZZZX85](https://openairdocs.org/sdr/98ZZZX85), Nov 12, 1997: HUB. VIBRATION. ERRATIC TRACK AND BALANCE .89 IPS AT 11:00 TO .15 AT 9:00 CHANGES BY SHAKING COLLECTIVE GRIP LENGTH. ALSO, APPEARS TO CHANGE BY PULLING ON BLADES.
- [SDR 98ZZZX28](https://openairdocs.org/sdr/98ZZZX28), Nov 12, 1997: BEARING. BINDING. IDLER BELLCRANK FOUND TO HAVE BOTH PIVOT BEARINGS PRELOADED TO THE POINT OF NO ROTATION OF BEARING. FOUND ON INCOMING PARTS INSPECTION.
- [SDR 98ZZZX27](https://openairdocs.org/sdr/98ZZZX27), Nov 12, 1997: BEARING. BINDING. IDLER BELLCRANK FOUND TO HAVE BOTH PIVOT BEARINGS PRELOADED TO A POINT OF NO ROTATION. FOUND ON ACCEPTANCE INSPECTION.
- [SDR 98ZZZX26](https://openairdocs.org/sdr/98ZZZX26), Nov 12, 1997: BEARING. BINDING. IDLER BELLCRANK HAS BOTH PIVOT BEARINGS PRELOADED TO A POINT OF NO ROTATION. FOUND ON INCOMING ACCEPTANCE INSPECTION.
- [SDR 98ZZZX25](https://openairdocs.org/sdr/98ZZZX25), Nov 12, 1997: BEARING. BINDING. IDLER BELLCRANK HAS BOTH PIVOT BEARINGS PRELOADED TO A POINT OF NO ROTATION. FOUND DURING INCOMING ACCEPTANCE INSPECTION.
- [SDR 98ZZZX24](https://openairdocs.org/sdr/98ZZZX24), Nov 12, 1997: BEARING. BINDING. IDLER BELLCRANK HAS BOTH PIVOT BEARINGS PRE-LOADED TO A POINT OF NO ROTATION. BINDING COULD CAUSE BOLT FAILURE. FOUND ON INCOMING ACCEPTANCE INSPECTION.

All 103: https://openairdocs.org/model/md-helicopters-500n/reports.md

## STCs that may be installed (OpenAirDocs) (176, 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 SA800EA](https://openairdocs.org/stc/SA800EA): Installation of Whelen Anti-Collision, Position, or Anti-Collision/Position Light System, and applicable associated power supplies. Whelen Aerospace Technologies
- [STC SR12310LA](https://openairdocs.org/stc/SR12310LA): Installation of MD Helicopters (MDH), LLC, 530N configuration kit. MD Helicopters, LLC
- [STC SR01050LA](https://openairdocs.org/stc/SR01050LA): Installation of main rotor blades P/N 500P2300-501/503/505. Helicopter Technology Company
- [STC SR12092IB](https://openairdocs.org/stc/SR12092IB): Manufacturing and Installation of Cargo Hold Nets. ICARUS AERO INC
- [STC SR01059LA](https://openairdocs.org/stc/SR01059LA): Installation of right side dual utility mount. Airfilm Camera Systems LLC
- [STC SH133WE](https://openairdocs.org/stc/SH133WE): Installation of C-75 cargo rack set. Isolair Inc
- [STC SH3686NM](https://openairdocs.org/stc/SH3686NM): Installation of an Isolair Model3700-110 spray tank system. (500N restricted category). Isolair Inc
- [STC SR00181IB](https://openairdocs.org/stc/SR00181IB): Installation of alternate Cabin Door Latches to replace OEM door locks. Aerologic LLC
- [STC SR00709AT](https://openairdocs.org/stc/SR00709AT): Installation of Starter-Generator Cooling Kit. Precision Heli-Support LLC
- [STC SR00771LA](https://openairdocs.org/stc/SR00771LA): Installation of right-side utility mount. Airfilm Camera Systems LLC
- [STC SR00772LA](https://openairdocs.org/stc/SR00772LA): Installation of left-side utility mount. Airfilm Camera Systems LLC
- [STC SR00862LA](https://openairdocs.org/stc/SR00862LA): Installation of aft belly utility mount. Airfilm Camera Systems LLC
- [STC SR04637CH](https://openairdocs.org/stc/SR04637CH): Replacement of existing main ship battery with Lithium Ion Battery and installation of Annunciator Control Panel. Airwolf Aerospace LLC
- [STC SR00068DE](https://openairdocs.org/stc/SR00068DE): Installation of infrared imaging system. Dart Aerospace Company
- [STC SH5247NM](https://openairdocs.org/stc/SH5247NM): Installation of external pod, camera mount, and 12 volt power provision. Dart Aerospace USA Inc
- [STC SH2735NM](https://openairdocs.org/stc/SH2735NM): Installation of pneumatic door actuators. Dart Aerospace USA Inc
- [STC SR02808LA](https://openairdocs.org/stc/SR02808LA): Installation of MD500 Side Pull Kit. Aerocraft Incorporated
- [STC SH5206NM](https://openairdocs.org/stc/SH5206NM): Installation of two underfuselage jacking hard points. Dart Aerospace USA Inc
- [STC SR00043LA](https://openairdocs.org/stc/SR00043LA): Installation of clip on Main Rotor Swashplate. Pac West Helicopters Inc
- [STC SH3319NM](https://openairdocs.org/stc/SH3319NM): Installation of Precise Flight Pulselite Control Unit in the Landing /Taxi Recognition Visual Control Light system,. Precise Flight Inc
- [STC SR01778SE](https://openairdocs.org/stc/SR01778SE): Installation of Onboard Systems International Cargo Hook Kits and Load Weigh Kit. Onboard Systems International LLC
- [STC SH2263NM](https://openairdocs.org/stc/SH2263NM): Installation of a fore-and-aft medical evacuation litter(s) kit. MD Helicopters LLC
- [STC SR04680NY](https://openairdocs.org/stc/SR04680NY): Installation of Human External Cargo (HEC) Long-Line Kit. Boost Human External Cargo Systems Inc
- [STC SR00314AT](https://openairdocs.org/stc/SR00314AT): Installation of engine firewall in Hughes 369 model helicopter. Thoroughbred Aviation Maintenance Inc
- [STC SR00450AT](https://openairdocs.org/stc/SR00450AT): Installation of a seat pan inspection panel. Thoroughbred Aviation Maintenance Inc
- [STC SR01839AT](https://openairdocs.org/stc/SR01839AT): Installation of cyclic friction levers. Thoroughbred Aviation Maintenance Inc
- [STC SR02859AT](https://openairdocs.org/stc/SR02859AT): Installation of Part Number 369HT21004 main rotor hub fairing as a direct replacement for OEM Part Number 369D21004-11 (BSC). Thoroughbred Aviation Maintenance Inc
- [STC SR03265AT](https://openairdocs.org/stc/SR03265AT): Modification of engine gearbox breather system by the installation of Heli-Tech "HT800-Engine Gearbox Breather Kit", P/N HT800. Thoroughbred Aviation Maintenance Inc
- [STC SR02693LA](https://openairdocs.org/stc/SR02693LA): Installation of a redundant system for the primary Cargo Hook system when conducting Human External Cargo (HEC) external loads operations. Onboard Systems International LLC
- [STC SH4908NM](https://openairdocs.org/stc/SH4908NM): Fabrication of Onboard Systems Model 200-034-00, 200-034-01, and 200-034-02 Load Weigh Kits. Onboard Systems International
- [STC SR00407SE](https://openairdocs.org/stc/SR00407SE): Fabrication of Onboard Systems Model 200-187-00 cargo hook kit. Onboard Systems International LLC
- [STC SR00525SE](https://openairdocs.org/stc/SR00525SE): Fabrication of Onboard Systems Model 200-231-00 and 200-231-01 Cargo Hook Attach Point Kit and installation of these Cargo Hook Attach Point Kits. Onboard Systems International
- [STC SR00892SE](https://openairdocs.org/stc/SR00892SE): Fabrication of Onboard Systems International Model 200-264-00, 200-264-01, and 200-264-02 Cargo Hook Kits. Onboard Systems International
- [STC SR02001SE](https://openairdocs.org/stc/SR02001SE): Fabrication and installation of Model 72448 locking fuel cover assembly. Timberline Aerospace LLC
- [STC SR02704SE](https://openairdocs.org/stc/SR02704SE): Installation and maintenance of the Sunspot 36 and 46 series lights. AeroLED's Holdings LLC
- [STC SR01343NY](https://openairdocs.org/stc/SR01343NY): Installation of main rotor blade tie down tips. VIH Aerospace Inc
- [STC SR04539NY](https://openairdocs.org/stc/SR04539NY): Installation of the Human External Cargo (HEC) System. Boost Human External Cargo Systems Inc
- [STC SR04194NY](https://openairdocs.org/stc/SR04194NY): Installation of a Garmin G500(H) TXi Display System. Aerospace Design & Compliance LLC
- [STC SH4655NM](https://openairdocs.org/stc/SH4655NM): Installation of Soloy 375-1000 series auxiliary fuel system. Fifty-Ten-Yankee LLC
- [STC SR02712LA](https://openairdocs.org/stc/SR02712LA): Installation of Torque Indicating Systems. Precision Heli-Support LLC
- [STC SR02124SE](https://openairdocs.org/stc/SR02124SE): Installation functionality. of Data Garmin Required: transponders: (1) Garmin GTX Master 345/345R Drawing with List ADS-B (MDL), Out and In 005-00734-A4, functionality;. Garmin International Inc
- [STC SH656GL](https://openairdocs.org/stc/SH656GL): Installation of auxiliary fuel system. Fargo Manufacturing Co
- [STC SH907GL](https://openairdocs.org/stc/SH907GL): Installation of a starter generator cooling system. Fargo Manufacturing Co
- [STC SR02129CH](https://openairdocs.org/stc/SR02129CH): Installation of Fargo 19-gallon auxiliary fuel tank with STC SH656GL. Fargo Manufacturing Co
- [STC SA615EA](https://openairdocs.org/stc/SA615EA): Installation of a Whelen Anti-Collision Strobe Light System as replacement for originally installed anti-collision lights. Whelen Aerospace Technologies
- [STC SR00359BO](https://openairdocs.org/stc/SR00359BO): Installation of Parmetheus Plus LED PAR36 and PAR46 taxi and landing lights. Whelen Aerospace Technologies
- [STC SH2554NM](https://openairdocs.org/stc/SH2554NM): Installation of Modified front window canopy. The NORDAM Group LLC
- [STC SH8418SW](https://openairdocs.org/stc/SH8418SW): Installation of pop out windows. The NORDAM Group LLC
- [STC SR00821DE](https://openairdocs.org/stc/SR00821DE): Installation of Automatic Dependent Surveillance - Broadcast (ADS-B) Out and in functionality using the BendixKing KT74 Transponder and qualified position sensor and ADS-B In Receiver. Peregrine
- [STC SR02058SE](https://openairdocs.org/stc/SR02058SE): Fabrication of Aerometals Fuel Vent Emergency Shutoff Valve Assembly in accordance with Aerometals Master Drawing List No. Aero-MDL-002, Revision A, dated February 24, 2010, or later FAA-approved revision; and installation of this assembly in accordance with Aerometals Installation Instructions No. Aero-Inst-001, Revision NC, dated April 07, 2009, or later FAA-approved revision. Aerometals

All 176: https://openairdocs.org/model/md-helicopters-500n/stcs.md

## The same model under other registry codes

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

- [Mcdonnell Douglas Helicopter 500N](https://openairdocs.org/model/mcdonnell-douglas-helicopter-500n): 27 registered aircraft, registry code 3027374

---
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.