# Airworthiness Directives; MD Helicopters, LLC Helicopters

**Action Urgency Score:** 65/100

| Field | Value |
|---|---|
| Agency | Transportation Department; Federal Aviation Administration |
| Type | Final rule |
| Action | Final rule. |
| Published | 2026-10-23 |
| Effective | 2026-11-27 |
| Significant | No |
| CFR parts | 14 CFR 39 |
| 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. |
| Document number | 2026-21664 |

## Why this score
- Effective date within 30 days.
- Final rule.

Source: Federal Register API (Office of the Federal Register) (https://www.federalregister.gov/documents/2026/10/23/2026-21664/airworthiness-directives-md-helicopters-llc-helicopters). Last refreshed: 2026-11-04T09:17:43.641Z.
Data from the Federal Register API; the published Federal Register document is authoritative. Informational only, not legal advice.