EASA AD CF-2023-11
Fuel System — Standpipe Assembly Sharp Edges Leading to Fuel Quantity Wiring Harness Chafing Condition
Summary
Canadian Airworthiness Directive CF-2023-11 addresses a fuel system issue on Bell Helicopter Textron Canada Limited model 407 helicopters, specifically serial numbers 54832 through 54931, 54933 through 54939, and 54942 through 54954. The directive concerns sharp edges on the standpipe assembly part number 407-062-032-103 that may cause chafing of the fuel quantity wiring harness. This condition could lead to fuel quantity indication errors or potential fuel tank ignition.
What Changed
CF-2023-11 introduces mandatory inspections and corrective actions for the fuel system standpipe assembly and fuel quantity wiring harness on affected Bell 407 helicopters. It requires inspection within 300 flight hours or 6 months and mandates rework or replacement if sharp edges or damage are found. This is a new directive addressing a quality control issue identified by Bell.
Why It Matters
This directive is critical for aviation professionals because it prevents potential fuel system failures that could compromise flight safety. Operators and maintenance teams must ensure compliance to avoid erratic fuel quantity readings or fuel tank ignition risks. Timely action helps maintain airworthiness and regulatory compliance under Canadian Aviation Regulations.
What To Do
Operators of affected Bell 407 helicopters must inspect the fuel system standpipe assembly and fuel quantity wiring harness within 300 flight hours or 6 months from March 9, 2023. If sharp edges or damage are found, the standpipe must be reworked and damaged wiring harnesses repaired or replaced before further flight. Follow Bell Alert Service Bulletin 407-21-124 and coordinate with Bell for disposition instructions as needed.
AI-generated summary from official EASA source document. Always verify against the original.