Summary
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.
Directive Details
AD Number
FAA-2026-4666
Document Number
2026-21664
Type
Rule
Publication Date
October 23, 2026
Effective Date
November 27, 2026
Affected Manufacturer
MD Helicopters, LLC
Criticality
routine
Emergency
No
Docket ID
Docket No. FAA-2026-4666
Topics
Official Documents
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