Introduction
The FAA has issued a new Special Airworthiness Information Bulletin (SAIB 2024-05) for Robinson R44 Raven I and II helicopters. SAIBs are non-regulatory information published by the FAA to provide guidance and recommendations for airworthiness concerns that are not yet considered unsafe conditions. You can find more information on SAIBs and search for SAIBs on the FAA’s website.
This SAIB (2024-05) is to alert owners, operators (pilots), maintenance technicians, and inspectors of an airworthiness concern regarding potential loosening of the gearmotor assembly (gearmotor) on belt-tension actuators (clutch).
Video
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Background
The FAA received reports of loose gearmotors on R44 helicopters from both domestic and international operators. Investigation determined the cause to be out-of-spec internal screws and potential missing thread lock in some gearmotors that left the manufacturer.
Robinson Service Bulletin (SB-115)
In September 2023, Robinson updated the R44 maintenance manual to include gearmotor assembly torque stripe verification in the 100-hour/annual inspection procedures. Additionally, Robinson released an R44 Service Bulletin (SB-115) in October 2023, requiring a one-time verification of gearmotor security and the application of a torque stripe for future visual inspections.
Pilot Preflight
During preflight checks, pilots should ensure the torque stripe is intact and the gearmotor is secure. If your R44 does not have a torque stripe, ask your mechanic to refer to the FAA SAIB and RHC’s SB-115 and the R44 Maintenance Manual.
More Info
For more information check out the following:
- SAIB 2024-05
- SAIBs on the FAA’s website
- R44 maintenance manual
- Service Bulletin SB-115
- Australian Transport Safety Bureau, Accident Investigation AO-2023-005
Feedback
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