Summary
The Federal Aviation Administration (FAA) proposes to adopt a new airworthiness directive (AD) that is applicable to Turbomeca S.A. Arriel 1 series turboshaft engines. This proposal would require initial and repetitive visual inspections for ingestive erosion, and cleaning if necessary, of M02 and M03 modules. This proposal is prompted by reports from the manufacturer of ingestive erosion of M02 and M03 modules. The actions specified by the proposed AD are intended to prevent an unbalance of the gas generator rotating assembly which may lead to deterioration of the gas generator rear bearing and uncommanded engine shutdown.