Type Record · As of May 3, 2026

MD HELICOPTERS INC 500N

Rotorcraft · ROLLS-ROYC 250-C20R/2

Registered

Year Range

2000–2018

NTSB Events

Airworthiness Directives

01 / Distribution

Where the fleet lives and was built

Counts of currently-registered MD HELICOPTERS INC 500N aircraft by US state and decade of manufacture, sourced from the FAA Aircraft Registry.

By State (top 10)

MD 28.6% 4
CA 14.3% 2
DE 14.3% 2
OR 7.1% 1
MT 7.1% 1
FL 7.1% 1
MO 7.1% 1
UT 7.1% 1
PA 7.1% 1

By Decade of Manufacture

2000s 64.3% 9
2010s 28.6% 4
Unknown 7.1% 1

02 / NTSB Records

Events involving MD HELICOPTERS INC 500N aircraft

1 event(s) on file. Showing the most recent 1.

Aug 2, 2006
N520AP
Louisville, Kentucky Minor
NTSB Docket →

03 / Airworthiness Directives

FAA directives applicable to MD HELICOPTERS INC 500N

37 directive(s) on file. Showing the most recent 25 · 12 more in the Federal Register.

Nov 18, 2025

Airworthiness Directives; MD Helicopters, LLC Helicopters

The FAA proposes to supersede Airworthiness Directive (AD) 2024-23-06, which applies to certain MD Helicopters, LLC (MDHI) Model 369, 369A, 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. AD 2024-23-06 requires repetitively inspecting the torque tube assembly and roller bearings, and de…

Atlas AD → Federal Register ↗
Sep 5, 2025

Airworthiness Directives; MD Helicopters, LLC

The FAA is adopting a new airworthiness directive (AD) for certain MD Helicopters, LLC, Model 369 (Army YOH-6A), 369A (Army OH- 6A), 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This AD was prompted by multiple reports of cracked tail rotor (T/R) pedal support brackets. This AD requi…

Atlas AD → Federal Register ↗
Nov 19, 2024

Airworthiness Directives; MD Helicopters, LLC, Helicopters

The FAA is adopting a new airworthiness directive (AD) for certain MD Helicopters, LLC (MDHI), Model 369, 369A, 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This AD was prompted by a report of a seized and damaged roller bearing in the pilot interconnecting cyclic torque tube (torque…

Atlas AD → Federal Register ↗
Oct 31, 2024

Airworthiness Directives; Various Helicopters

The FAA is adopting a new airworthiness directive (AD) for various helicopters modified by certain supplemental type certificates (STCs) that approve the installation of an emergency float kit or an emergency float with a liferaft kit. This AD was prompted by the results of an accident investigation and subsequent rep…

Atlas AD → Federal Register ↗
Aug 28, 2024

Airworthiness Directives; MD Helicopters, LLC, Helicopters

The FAA proposes to adopt a new airworthiness directive (AD) for certain MD Helicopters, LLC, Model 369 (Army YOH-6A), 369A (Army OH-6A), 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This proposed AD was prompted by multiple reports of cracked tail rotor (T/R) pedal support brackets.…

Atlas AD → Federal Register ↗
Aug 8, 2024

Airworthiness Directives; MD Helicopters, LLC, Helicopters

The FAA proposes to adopt a new airworthiness directive (AD) for certain MD Helicopters, LLC (MDHI), Model 369, 369A, 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This proposed AD was prompted by a report of a seized and damaged roller bearing in the pilot interconnecting cyclic torq…

Atlas AD → Federal Register ↗
Apr 25, 2024

Airworthiness Directives; Various Helicopters

The FAA proposes to adopt a new airworthiness directive (AD) for various helicopters modified by certain supplemental type certificates (STCs) that approve the installation of an emergency float kit or an emergency float with liferaft kit. This proposed AD was prompted by the results of an accident investigation and s…

Atlas AD → Federal Register ↗
Dec 6, 2021

Airworthiness Directives; MD Helicopters Inc. (MDHI) Helicopters

The FAA is adopting a new airworthiness directive (AD) for certain MD Helicopters Inc. (MDHI), Model 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This AD was prompted by a report of a spiral crack in the pilot-to-copilot tail rotor torque tube (torque tube). This AD requires a one-ti…

Atlas AD → Federal Register ↗
Aug 13, 2021

Airworthiness Directives; MD Helicopters Inc. (MDHI) Helicopters

The FAA proposes to adopt a new airworthiness directive (AD) for MD Helicopters Inc. (MDHI), Model 369D, 369E, 369F, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This proposed AD was prompted by a report of a spiral crack in the pilot-to-copilot tail rotor torque tube (torque tube). This proposed AD w…

Atlas AD → Federal Register ↗
Sep 23, 2020

Airworthiness Directives; MD Helicopters Inc. (MDHI), Helicopters

The FAA is adopting a new airworthiness directive (AD) for certain MD Helicopters Inc. (MDHI) Model 369A, 369D, 369E, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This AD was prompted by reports of abrasion strips departing the main rotor (MR) blade in- flight. This AD requires tap inspecting each MR…

Atlas AD → Federal Register ↗
May 26, 2020

Airworthiness Directives; MD Helicopter Inc., Helicopters

The FAA is adopting a new airworthiness directive (AD) for MD Helicopters Inc., (MDHI) Model 369D, 369E, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This AD was prompted by a report of non-conforming main rotor (M/R) hub lead-lag bolts (bolts). This AD requires removing certain bolts from service. Th…

Atlas AD → Federal Register ↗
May 14, 2020

Airworthiness Directives; MD Helicopters Inc. (MDHI), Helicopters

The FAA proposes to adopt a new airworthiness directive (AD) for certain MD Helicopters Inc. (MDHI), Model 369A, 369D, 369E, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This proposed AD would require tap inspecting each main rotor (MR) blade leading edge abrasion strip and is prompted by reports of a…

Atlas AD → Federal Register ↗
Feb 7, 2020

Airworthiness Directives; MD Helicopters Inc., Helicopters

The FAA proposes to adopt a new airworthiness directive (AD) for MD Helicopters Inc., (MDHI) Model 369D, 369E, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This proposed AD was prompted by a report of non-conforming main rotor (M/R) hub lead-lag bolts (bolts). This proposed AD would require removing c…

Atlas AD → Federal Register ↗
Mar 13, 2019

Airworthiness Directives; MD Helicopters, Inc. (MDHI), Helicopters

We are adopting a new airworthiness directive (AD) for MDHI Model 369A, 369D, 369E, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This AD requires inspecting each main rotor blade (MRB) for a crack. This AD was prompted by reports of cracked MRBs. The actions of this AD are intended to address an unsaf…

Atlas AD → Federal Register ↗
Nov 26, 2018

Airworthiness Directives; MD Helicopters Inc. (MDHI) Helicopters

We propose to adopt a new airworthiness directive (AD) for MDHI Model 369A, 369D, 369E, 369FF, 369H, 369HE, 369HM, 369HS, 500N, and 600N helicopters. This proposed AD would require inspecting each main rotor blade (MRB) for a crack. This proposed AD is prompted by reports of cracked MRBs. The actions of this proposed…

Atlas AD → Federal Register ↗
Mar 11, 2016

Airworthiness Directives; MD Helicopters, Inc. (MDHI) Helicopters

We are adopting a new airworthiness directive (AD) for certain MDHI Model 369A (Army OH-6A), 369H, 369HE, 369HM, 369HS, 369D, 369E, 369F, 369FF, and 500N helicopters. This AD requires inspecting the auxiliary fuel pump (fuel pump) wire routing in the left-hand fuel cell and corrective action, if necessary. This AD als…

Atlas AD → Federal Register ↗
Feb 25, 2016

Airworthiness Directives; MD Helicopters Inc., Helicopters

We are adopting a new airworthiness directive (AD) for MD Helicopters, Inc. (MDHI), Model 369A, 369D, 369E, 369FF, 369HE, 369HM, 369HS, 500N, and 600N helicopters with a certain part-numbered main rotor blade attach pin (pin) installed. This AD requires ensuring the life limit of the pin as listed in the Airworthiness…

Atlas AD → Federal Register ↗
Jan 21, 2016

Airworthiness Directives; MD Helicopters Inc.

We are adopting a new airworthiness directive (AD) for MD Helicopters Inc. (MDHI) Model 500N and 600N helicopters with certain rotating cone assemblies installed. This AD requires establishing a life limit of 10,000 hours time-in-service (TIS) on these rotating cone assemblies. This AD was prompted by the determinatio…

Atlas AD → Federal Register ↗
Sep 2, 2015

Airworthiness Directives; MD Helicopters Inc. (MDHI) Helicopters

We propose to adopt a new airworthiness directive (AD) for certain MDHI Model 369A (Army OH-6A), 369H, 369HE, 369HM, 369HS, 369D, 369E, 369F, 369FF, and 500N helicopters. This proposed AD would require inspecting the auxiliary fuel pump (fuel pump) wire routing in the left-hand fuel cell and corrective action, if nece…

Atlas AD → Federal Register ↗
Sep 2, 2015

Airworthiness Directives; MD Helicopters Inc., Helicopters

We propose to adopt a new airworthiness directive (AD) for MD Helicopters Inc. (MDHI) Model 369A, 369D, 369E, 369FF, 369HE, 369HM, 369HS, 500N, and 600N helicopters with a certain part-numbered main rotor blade attach pin (pin) installed. This proposed AD would require ensuring the life limit of the pin as listed in t…

Atlas AD → Federal Register ↗
Jun 9, 2015

Airworthiness Directives; MD Helicopters Inc.

We propose to adopt a new airworthiness directive (AD) for MD Helicopters Inc. (MDHI) Model 500N and 600N helicopters with certain rotating cone assemblies installed. This proposed AD would require establishing a life limit of 10,000 hours time-in-service (TIS) on these rotating cone assemblies. This proposed AD is pr…

Atlas AD → Federal Register ↗
Feb 8, 2013

Airworthiness Directives; MD Helicopters, Inc., Helicopters

We are adopting a new airworthiness directive (AD) for MD Helicopters, Inc. (MDHI) Model 500N, 600N and MD900 helicopters to require determining the cure date for each NOTAR fan blade tension- torsion strap (T-T strap), establishing a calendar-time retirement life for certain T-T straps, reducing the retirement life o…

Atlas AD → Federal Register ↗
Jul 19, 2012

Airworthiness Directives; MD Helicopters, Inc. (MDHI) Helicopters

We propose to adopt a new airworthiness directive (AD) for MDHI Model 500N, 600N, and MD900 helicopters to require determining the cure date for each NOTAR fan blade tension-torsion strap (T-T strap), establishing a calendar-time retirement life for certain T-T straps, reducing the retirement life of certain T-T strap…

Atlas AD → Federal Register ↗
Jan 14, 2011

Airworthiness Directives; MD Helicopters, Inc. (MDHI) Model MD900 Helicopters

This document proposes superseding an existing airworthiness directive (AD) for MDHI Model MD900 helicopters. That AD currently requires turning on both Vertical Stabilizer Control System (VSCS) switches and turning off the autopilot (AP/SAS) switch; pulling certain AP/SAS circuit breakers; installing a placard near t…

Atlas AD → Federal Register ↗
Dec 2, 2008

Airworthiness Directives; MD Helicopters, Inc. Model MD900 Helicopters

This document supersedes AD 2008-18-52 and publishes in the Federal Register an amendment adopting Emergency Airworthiness Directive (AD) 2008-22-53 which was sent previously to all known U.S. owners and operators of MD Helicopters, Inc. (MDHI) Model MD900 helicopters by individual letters. This AD requires turning ON…

Atlas AD → Federal Register ↗

07 / PMA replacement parts

FAA-approved replacement parts for MD HELICOPTERS INC 500N

22 parts on file from the FAA Parts Manufacturer Approval database. Each is a non-OEM part the FAA has authorized for use as a replacement on this aircraft type.

10620HS9-1, 10620HS9-2, 10620HS9-3, 10620HS9-4, 10620HS9-5, 10620HS9-6, 10620HS9-7, 10620HS9-8, 10620HS9-9, 10620HS9-10, 10620HS9-11, 10620HS9-12, 10620HS9-13, 10620HS9-14, 10620HS9-15, 10620HS9-16, 10620HS9-17, 10620HS9-18, 10620HS9-19, 10620HS9-20, 10620HS9-21, 10620HS9-22, 10620HS9-23, 10620HS9-24, 10620HS9-25, 10620HS9-26, 10620HS9-27, 10620HS9-28, 10620HS9-29, 10620HS9-30, 10620HS9-31, 10620HS9-32, 10620HS9-33#https://drs.faa.gov/browse/excelExternalWindow/952AAD173EC3B8DB8625825200659844.0001##

P/B Switch

Ducommun Technlogies Inc replaces 10620HS9-1, 10620HS9-2, 10620HS9-3, 10620HS9-4, 10620HS9-5, 10620HS9-6, 10620HS9-7, 10620HS9-8, 10620HS9-9, 10620HS9-10, 10620HS9-11, 10620HS9-12, 10620HS9-13, 10620HS9-14, 10620HS9-15, 10620HS9-16, 10620HS9-17, 10620HS9-18, 10620HS9-19, 10620HS9-20, 10620HS9-21, 10620HS9-22, 10620HS9-23, 10620HS9-24, 10620HS9-25, 10620HS9-26, 10620HS9-27, 10620HS9-28, 10620HS9-29, 10620HS9-30, 10620HS9-31, 10620HS9-32, 10620HS9-33
PMA holder →
041089-XXXXXXX#https://drs.faa.gov/browse/excelExternalWindow/0CD710C456EE5AAB8625859100507DB4.0001##

Cable PCIU to Gimbal Control

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
041072-XXXXXXX#https://drs.faa.gov/browse/excelExternalWindow/25F0F8BA0478F23E8625859100507E6F.0001##

Cable PCIU MKIl Slave

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
041086-XXXXXXX#https://drs.faa.gov/browse/excelExternalWindow/1962E47631D1DEF98625859100507D06.0001##

Cable PCIU to Gimbal Power

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
211000-XXXXXXX#https://drs.faa.gov/browse/excelExternalWindow/1C553D7A74354A3B8625859100507BFE.0001##

A800 Gimbal Assembly

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
041087-XXXXXXX#https://drs.faa.gov/browse/excelExternalWindow/48F18B4D2393F6D68625859100507D43.0001##

Cable PCIU to Gimbal Control

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
041088-XXXXXXX#https://drs.faa.gov/browse/excelExternalWindow/5B84BBEC358A510B8625859100507D78.0001##

Cable PCIU to Gimbal Power

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
037003#https://drs.faa.gov/browse/excelExternalWindow/71CBC60921C25B7D8625859100507F5B.0001##

Dovetail Mounting Plate, Type I, Upper

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
012025#https://drs.faa.gov/browse/excelExternalWindow/708BA1C3C552E1428625859100507EE9.0001##

PCIU Mounting Tray Assembly

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
041111#https://drs.faa.gov/browse/excelExternalWindow/6AB7B5283E32E8F98625859100507EAA.0001##

Cable Coilded Controller - 6 Way

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
011016-XXXXXXX#https://drs.faa.gov/browse/excelExternalWindow/A8FD5A0B42D8ADAE8625859100507C3D.0001##

PCIU MKII

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
091011#https://drs.faa.gov/browse/excelExternalWindow/B884AF2191B134A28625859100507F1B.0001##

Grip Controller Mounting Bracket

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
041071-XXXXXXX#https://drs.faa.gov/browse/excelExternalWindow/C42453749CB44DA18625859100507E32.0001##

Cable PCIU MKII Power In

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
041068-0000010#https://drs.faa.gov/browse/excelExternalWindow/C3301D9C2FAE81A58625859100507CC5.0001##

Trakka Cable MD 520 Cable Kit

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
041110-XXXXXXX#https://drs.faa.gov/browse/excelExternalWindow/E39A0C25D2D2161B8625859100507DF2.0001##

Cable PCIU MKII to TCP and Grip Controller

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
021015-0101000#https://drs.faa.gov/browse/excelExternalWindow/E401E12617E178BD8625859100507C86.0001##

Grip Control, Black Light

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
037322#https://drs.faa.gov/browse/excelExternalWindow/F203A16191B6EF3A8625859100507F96.0001##

Dovetail Mounting Assembly

Trakka Systems USA, LLC replaces Modification Part
PMA holder →
369-430-100#https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID197463610620220927150325.0001##

369 HUMAN EXTERNAL CARGO HOOK SYSTEM

Mechanical Specialties LLC replaces Modification Part
PMA holder →
M2002-9#https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID175819960920240802183933.0001##

Brush, Electrical Contact

Miraj Corporation replaces 200SGL1009
PMA holder →
#https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID132285269820220819173041.0001##

Wesco Manufacturing, Inc.
PMA holder →
WM150SG-K1#https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID128739939020220816120605.0001##

Overhaul Hardware Kit 150SG, 160SG Series Starter Generators

Wesco Manufacturing, Inc. replaces Aircraft Parts Corporation (APC)/Skurka 150SGXXXX, 160SGXXXX Starter Generators Per Wesco Manufacturing Content List Document No.: WM1002K-1 Rev.: NR Date: 8/1/22 or later FAA-approved revisions
PMA holder →
M150SG1379-8#https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID183008701220220808142319.0001##

Washer, Lock

Miraj Corporation replaces 150SG1379-8
PMA holder →

04 / Regulations watching this type

Advisory Circulars and Federal Register activity for MD HELICOPTERS INC 500N

Advisory Circulars

No ACs explicitly mention this type. Showing universal operating-rule ACs that apply to all aircraft.

Recent Federal Register activity

Latest rulemakings touching general operating rules (Part 91) and maintenance rules (Part 43).

05 / Aircraft of this type

All 14 registered N-numbers

Every tail currently on the FAA registry for this make/model. Click an N-number to query the FAA Aircraft Inquiry; rows flagged ● have NTSB events on file. Tails seeded with full TallyAero pages link directly.

14 of 14

N-number	St	Year	Status	NTSB	FAA
N103CG	CA	2006	Active	·	Look up ↗
N33C	DE	2018	Active	·	Look up ↗
N515TH	OR	2002	Active	·	Look up ↗
N520AP	DE	2001	Active	●	Look up ↗
N520GK	MT	2002	Active	·	Look up ↗
N520PD	CA	2014	Active	·	Look up ↗
N520VC	FL	2015	Active	·	Look up ↗
N523HB	MO	2007	Active	·	Look up ↗
N70512	UT	2000	Active	·	Look up ↗
N910PG	MD	2000	Active	·	Look up ↗
N911PG	MD	2000	Active	·	Look up ↗
N912PG	MD	—	Active	·	Look up ↗
N913PG	MD	2008	Active	·	Look up ↗
N977WF	PA	2013	Active	·	Look up ↗

Source — FAA Aircraft Registry · click "Look up" to query the live registry record (owner, address, last airworthiness)

05 / Sources & Methodology

Every count traces back to a primary US-government source

FAA Aircraft Registry →
Refreshed Apr 27, 2026

Available
NTSB CAROL →
Refreshed Apr 27, 2026

Available
Federal Register (FAA Airworthiness Directives) →
Refreshed Apr 27, 2026

Available

We render counts and lists as the agency publishes them. Read the methodology →