AD 2021-20-02 Requires Determining The Total Hours Time-In-Service Of Certain Part-Numbered Main Rotor Grip Assemblies

The FAA is adopting a new airworthiness directive (AD) for certain Bell Textron Inc. (type certificate previously held by Bell Helicopter Textron Inc.) Model 205B helicopters.

This AD was prompted by a notification of certain parts needing a life limit. This AD requires determining the total hours time-in-service (TIS) of certain part-numbered main rotor grip assemblies (grip assemblies), establishing a life limit for certain part-numbered grip assemblies, removing from service any grip assembly that has reached or exceeded its retirement life, creating a component history card, and removing any grip assembly from service before reaching its retirement life. This AD also prohibits installing certain grip assemblies unless the life limit was established in accordance with this AD. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective October 28, 2021.

Supplementary Information: The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to Bell Textron Inc. Model 205B helicopters with grip assembly part number (P/N) 204-011-121-005, P/N 204-011-121-113, or P/N 204-011-121-117 installed. The NPRM published in the Federal Register on June 10, 2021 (86 FR 30824). The NPRM was prompted by a notification from Bell of established life limits for certain part numbered grip assemblies that were not included in Chapter 4, Airworthiness Limitations Schedule (ALS) of Bell Helicopter 205B Maintenance Manual BHT-205B-MM-1, Revision 1, dated July 15, 1993. Bell states the life limit of 9,000 hours TIS for grip assembly part number (P/N) 204-011-121-005, P/N 204-011-121-113, and P/N 204-011-121-117 was left out of the ALS for Model 205B helicopters. Bell states this may suggest that these part numbers have an unlimited life when installed on Model 205B helicopters, whereas the retirement life is 9,000 hours TIS. This condition, if not addressed, could result in fatigue and failure of the grip assembly and loss of control of the helicopter.

Accordingly, Bell specifies updating the existing ALS to establish a life limit of 9,000 hours TIS for grip assembly P/N 204-011-121-005, P/N 204-011-121-113, and P/N 204-011-121-117. The FAA is issuing this AD to address the unsafe condition on these products.

FMI: www.regulations.gov