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FAA · Airworthiness Directive

Airworthiness Directives; Robinson Helicopter Company Helicopters

AD 2024-21921 Published 2024-09-26 1 model 550 US-registered tails affected Federal Register ↗

Abstract

The FAA is adopting a new airworthiness directive (AD) for all Robinson Helicopter Company Model R44 and R44 II helicopters. This AD was prompted by reports of a fractured clutch shaft forward yoke (yoke) on the main rotor (M/R) drive due to fatigue cracking. This AD requires visually inspecting a certain part-numbered flex plate assembly (flex plate) and certain part-numbered yokes, including each flex plate bolt, and depending on the inspection results, removing an affected part from service and replacing an affected part with an airworthy part. This AD also requires removing a certain part-numbered yoke from service after accumulating a certain number of hours time-in-service (TIS) or a certain number of years, or as an alternative to removing the part from service, performing a 10x or higher power magnification visual inspection and, if needed, a magnetic particle inspection. The FAA is issuing this AD to address the unsafe condition on these products.

Applicability

Aircraft makes and models this AD applies to, sorted by US-registered fleet size.

Federal Register text

Verbatim from the Federal Register publication — required actions, compliance times, parts/serial numbers, and methods of compliance. The Federal Register is the legally binding document; this rendering is for readability. Cite: 89 FR 78785.

[Federal Register Volume 89, Number 187 (Thursday, September 26, 2024)] [Rules and Regulations] [Pages 78785-78791] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 2024-21921]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-0237; Project Identifier AD-2023-00491-R; Amendment 39-22853; AD 2024-19-11] RIN 2120-AA64

Airworthiness Directives; Robinson Helicopter Company Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all Robinson Helicopter Company Model R44 and R44 II helicopters. This AD was prompted by reports of a fractured clutch shaft forward yoke (yoke) on the main rotor (M/R) drive due to fatigue cracking. This AD requires visually

[[Page 78786]]

inspecting a certain part-numbered flex plate assembly (flex plate) and certain part-numbered yokes, including each flex plate bolt, and depending on the inspection results, removing an affected part from service and replacing an affected part with an airworthy part. This AD also requires removing a certain part-numbered yoke from service after accumulating a certain number of hours time-in-service (TIS) or a certain number of years, or as an alternative to removing the part from service, performing a 10x or higher power magnification visual inspection and, if needed, a magnetic particle inspection. The FAA is issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective October 31, 2024.

View on Federal Register ↗