EASA AD US-2025-11-07
Main Rotor Drive - Clutch Shaft Forward Yoke - Inspection / Removal / Replacement
Summary
The Federal Aviation Administration's Airworthiness Directive 2025-11-07 is a final rule addressing Robinson Helicopter Company Model R44 and R44 II helicopters. It mandates inspections and possible replacements of the main rotor drive clutch shaft forward yoke and flex plate assembly to detect fatigue cracking and prevent unsafe conditions. This directive updates previous requirements to clarify inspection procedures and introduces a specific paint remover option for alternative inspections.
What Changed
Airworthiness Directive 2025-11-07 supersedes AD 2024-19-11 by clarifying that alternative inspections of the clutch shaft forward yoke are repetitive and adding a new approved paint remover for these inspections. It also revises compliance wording to allow installation of yokes after magnetic particle inspection and updates inspection procedures accordingly.
Why It Matters
This directive is critical for aviation professionals to prevent potential failure of the main rotor drive due to fatigue cracking in the clutch shaft forward yoke, which could lead to loss of helicopter control. Operators and maintenance teams must adhere to the clarified inspection intervals and methods to ensure continued airworthiness and safety. Compliance helps avoid costly unscheduled repairs and enhances operational reliability.
What To Do
Operators of Robinson R44 and R44 II helicopters must perform visual inspections of the flex plate and yokes within 100 hours time-in-service after July 11, 2025, and follow repetitive inspection schedules as specified. If any cracks, corrosion, or loose fasteners are found, affected parts must be removed and replaced before further flight. Alternative inspections using the specified paint remover and magnetic particle inspection are allowed under clarified conditions.