EASA SIB 2010-08
Engine-driven Cooling Fan Disk Failures
Summary
EASA Safety Information Bulletin 2010-08 is an advisory document addressing engine-driven cooling fan disk failures in helicopters powered by vertical piston engines using thin sheet metal fan disks. It supports the Australian CASA Airworthiness Bulletin 63-007, which highlights the importance of proper maintenance and operation of these cooling fans to prevent catastrophic failures. The bulletin applies to all affected piston-engine helicopters registered in EU Member States and associated countries.
What Changed
This bulletin introduces a consolidated advisory emphasizing the risks of cooling fan disk failures due to fatigue cracking and operational exceedances, such as prolonged operation in critical RPM bands. It reinforces CASA's recommendations on strict adherence to manufacturer-approved maintenance and operational procedures for cooling fans and their drive systems.
Why It Matters
The bulletin is crucial for aviation professionals because cooling fan disk failures can cause severe damage to helicopter components, including flight controls, potentially leading to loss of control. Proper maintenance and operational practices reduce the risk of fan blade liberation and catastrophic failure, ensuring flight safety and reliability of piston-engine helicopters.
What To Do
Operators, maintainers, and owners should review and strictly follow the current manufacturer-approved maintenance data and operational limits for cooling fans and their drive systems. Regular inspections for corrosion, damage, and correct fan balance must be conducted, and any repairs should comply with approved data. There is no mandatory compliance deadline, but adherence to these recommendations is strongly advised to prevent failures.
AI-generated summary from official EASA source document. Always verify against the original.