Narrative:

During a routine inspection and calibration of the torque mutipliers used on the aft engine mount bolts for the PW4000 (small engines), it was found that the wrong handle was used with the torque multiplier. Although the handles are interchangeable, the torque tables on the handles are different between the 392 and 392-a torque multipliers. Therefore, the input torques will give a different output torque when the handle label is not matched to the proper torque multiplier. Since oct/01, approximately 50 engines were produced from our engine shop. It is known how many of those engines may have had the aft mount bolts 'under-torqued' because of this mix-up. Management has been advised of the problem and has taken the necessary steps to correct any discrepancies in this process.

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Original NASA ASRS Text

Title: A SHOP TECHNICIAN RPTS INCORRECT TORQUE MAY HAVE BEEN APPLIED TO THE AFT ENG MOUNTS ON AS MANY AS 50 ENGS. CAUSED BY IMPROPER TOOLING.

Narrative: DURING A ROUTINE INSPECTION AND CALIBRATION OF THE TORQUE MUTIPLIERS USED ON THE AFT ENG MOUNT BOLTS FOR THE PW4000 (SMALL ENGS), IT WAS FOUND THAT THE WRONG HANDLE WAS USED WITH THE TORQUE MULTIPLIER. ALTHOUGH THE HANDLES ARE INTERCHANGEABLE, THE TORQUE TABLES ON THE HANDLES ARE DIFFERENT BTWN THE 392 AND 392-A TORQUE MULTIPLIERS. THEREFORE, THE INPUT TORQUES WILL GIVE A DIFFERENT OUTPUT TORQUE WHEN THE HANDLE LABEL IS NOT MATCHED TO THE PROPER TORQUE MULTIPLIER. SINCE OCT/01, APPROX 50 ENGS WERE PRODUCED FROM OUR ENG SHOP. IT IS KNOWN HOW MANY OF THOSE ENGS MAY HAVE HAD THE AFT MOUNT BOLTS 'UNDER-TORQUED' BECAUSE OF THIS MIX-UP. MGMNT HAS BEEN ADVISED OF THE PROB AND HAS TAKEN THE NECESSARY STEPS TO CORRECT ANY DISCREPANCIES IN THIS PROCESS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.