Robinson Helicopter Service Bulletin Targets Governor Controller Upgrades

According to the FAA, service bulletins are issued by aircraft manufacturers to inform owners and operators about "critical and useful information on aircraft safety, maintenance, or product improvement."

The SB, issued June 28, affects controllers with part number D270-1, revisions A through E, that were factory installed on R44 helicopters with serial numbers 2625 through 2751, R44 Cadet helicopters with serial numbers 30061, and 30071 through 30093, and R44 II helicopters with serial numbers 14364, and 14412 through 14640.

According to Robinson, the service bulletin is the result of a concern about the potential for a moisture incursion that may cause a D270-1 governor controller malfunction. This bulletin requires exchanging Revision A through E controllers for Revision F, or subsequent controllers, which incorporate additional moisture protection.

The SB also impacts factory installations on R22 helicopters with serial numbers 4825 through 4887. In addition, the affected governor controllers were also shipped as spares from October 2020 through May 2023.

Robinson Helicopters estimates complying with the service bulletin will cost approximately $1,800 per unit and take two hours.

Once the new governor controller is installed, it should be tested by having an appropriately rated person at the controls perform the starting engine and run-up checklist, per Section 4 of the R44 and R22 pilot's operating handbook. The helicopter should be operated for five minutes to verify proper governor operation.

The engine monitoring unit (EMU) should then be programmed per the R22 and R44 technicians guide, ensuring the host computer has EMU technician's software version 1.0.1.1, released June 2023, or subsequent. Appropriate maintenance record entries should then be made.

The date for compliance with the service bulletin is February 29, 2024.