| 2016-01-19 | MD Helicopters Inc. | Feb 25, 2016 | Airframe (600N)Only with: Model 500N with rotating cone assembly P/N 500N3740-81 installed; Model 600N with rotating cone assembly P/N 500N3740-71 installed. |
| 2013-03-03 | MD Helicopters, Inc., Helicopters | Mar 15, 2013 | Airframe (600N)Only with: Models 500N and 600N with NOTAR fan blade T-T strap P/N 500N5311-5 installed; Model MD900 with T-T strap P/N 500N5311-5, 900R3442009-101, 900R3442009-103, or 900R6442009-103 installed. |
| 2008-22-52 | MD Helicopters, Inc. Model 500N and 600N Helicopters | Dec 15, 2008 | Airframe (600N)Only with: YSAS adapter tube P/N 500N7218-1 installed, excluding adapter tubes that have a production date code stamp. |
| 2008-20-05 | MD Helicopters, Inc. Model 600N Helicopters | Oct 27, 2008 | Airframe (600N)Certain serial numbers: 600N RN003–RN058. Only with: Applies only to helicopters not modified in the fuselage aft section to strengthen the tailboom attachments and longerons per MDHI Technical Bulletin TB600N-007 (original, Revision 1, or Revision 2). |
| 2005-21-02 | MD Helicopters, Inc. Model 369D, 369E, 369F, 369FF, 500N, and 600N Helicopters | Nov 1, 2005 | Airframe (600N)Only with: With an MDHI main rotor blade installed, or modified per HTC STC No. SR09172RC, SR09074RC, or SR01050LA with an HTC blade installed, as listed in the AD table by part number. |
| 2003-16-11 | MD Helicopters, Inc., Model 600N Helicopters | Sep 30, 2003 | Airframe (600N)Only with: Main rotor drive shaft assembly P/N 600N5510-1 installed. |
| 2001-24-51 | MD Helicopters, Inc. Model 600N Helicopters | Apr 29, 2002 | Airframe (600N)Certain serial numbers: 600N RN003–RN063 |
| 2000-08-22 | MD Helicopters Inc. Model 369D, 369E, 500N, and 600N Helicopters | May 22, 2000 | Airframe (600N)Only with: Analog/digital TOT indicator P/N 369D24513-1 installed (369D, 369E, 500N) or P/N 9A3420 installed (600N). |
| 99-20-12 | MD Helicopters Inc. Model 369D, D369E, 369FF, 500N, and 600N Helicopters | Nov 4, 1999 | Airframe (600N)Only with: Oil cooler blower bracket P/N 369F5190-1 installed. |
| 99-17-18 | MD Helicopters, Inc. Model 600N Helicopters | Sep 24, 1999 | Airframe (600N) |