Airworthiness Directives; MD Helicopters, LLC Helicopters
The FAA is adopting a new airworthiness directive (AD) for certain MD Helicopters, LLC (MDHI) Model 369D, 369E, 369F, 369FF, 369H, and 500N helicopters. This AD was prompted by a report of mechanical damage to the main transmission drive shaft coupling (coupling). This AD requires a one-time visual inspection of the couplings for cracks of the splines and, depending on the results, replacement of the couplings. The FAA is issuing this AD to address the unsafe condition on these products.
What this item does
The short version, using the agency's own summary text.
The FAA is adopting a new airworthiness directive (AD) for certain MD Helicopters, LLC (MDHI) Model 369D, 369E, 369F, 369FF, 369H, and 500N helicopters. This AD was prompted by a report of mechanical damage to the main transmission drive shaft coupling (coupling). This AD requires a one-time visual inspection of the couplings for cracks of the splines and, depending on the results, replacement of the couplings. The FAA is issuing this AD to address the unsafe condition on these products.
Final rule.
Important dates
The dates that matter most for this item.
Published
October 23, 2026
Starts
November 27, 2026
Who published it
The agencies listed in the official filing.
Federal rulebook sections mentioned
These are the parts of the Code of Federal Regulations cited in the filing.