Summary
The FAA proposes to adopt a new airworthiness directive (AD) for Honeywell International Inc. (formerly AlliedSignal Inc. and Garrett Turbine Engine Co.) TFE731-2 and -3 series turbofan engines with certain part number (P/N) low pressure turbine (LPT) stage 1 disks installed. This proposed AD would require for TFE731-2 and -2C series engines, initial and repetitive measurements and calculations to determine acceptance, and adjustment or replacement if necessary, of the LPT stage 1 nozzle assembly. This proposed AD would also require for TFE731-3, -3A, -3AR, -3B, -3BR, and -3R series engines, replacement of LPT stage 1 disks with serviceable disks. This proposed AD also allows replacement of the LPT stage 1 disk with a disk having a part number not listed in the proposed AD as optional terminating action to the repetitive actions. This proposal results from a report of an uncontained failure of the LPT stage 1 disk installed in a TFE731-3-1H turbofan engine. We are proposing this AD to prevent additional uncontained failure of the LPT stage 1 disk, and possible damage to the airplane.