AD 2004-09-29 69 FR 26022

The FAA is adopting a new airworthiness directive (AD) for Honeywell International Inc. (formerly AlliedSignal Inc., Garrett Turbine Engine Company, and AiResearch Manufacturing Company of Arizona) (Honeywell) TPE331-10 and -11 series turboprop engines with certain part numbers (P/Ns) and serial numbers (SNs) of first stage turbine disks. This AD requires initial and repetitive fluorescent penetrant inspections (FPIs) and eddy current inspections (ECIs) of the affected first stage turbine disks. This AD results from a report of a first stage turbine disk found cracked at the disk bore. The crack originated from a localized; melt related, low-alloy area of the disk. We are issuing this AD to prevent cracked first stage turbine disks from causing uncontained disk separation, resulting in engine damage and shutdown and damage to the airplane.