Narrative:

On aug/xa/98, I was asked to perform a borescope inspection of the #2 engine high pressure turbine stage 1. The aircraft was a DC10-10 with CF6-6 engines, nose number xyz. While viewing the blades from the trailing edge, I found 1 blade with a defect in the radius approximately mid span. The defect was a small hole in the outer layer of the blade with a crack going out of it up and aft at a 45 degree angle toward the trailing edge. ZZZ line maintenance control was notified in which he asked us to video the defect and send it to him. After he viewed it he contacted the engineer at home who was over that area of the engine and we all got on a conference call. I described again what I saw and the controller concurred. The engineer said it sounded like a striation or erosion line in the blade and to go ahead and create a deferred item to have it re-evaluated in 4 cycles. The maintenance manual reference they told me to defer it by was for this defect in the tip area of the blade, not in the radius. The deferred number was yxyx. In the course of conversation, I also found out that the engine in the #1 position was egt limited and was to be changed (next engine out of the shop) on sep/xb/98 or sep/xc/98. The next night the engine was re-borescoped by the engineer and signed off as 'could not locate defect.' there was no effort to contact us to discuss it, they had pictures of the defect, and still just signed it off. I feel that I was given wrong information when making the deferred item and it was incorrectly deferred when it left WWW. I understand that air carrier has a very limited supply of spare engines for this aircraft, which could be another contributing factor.

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Original NASA ASRS Text

Title: A DC10-10 ON BORESCOPE INSPECTION FOUND 1 BLADE WITH DEFECT. VIDEO TAPED DEFECT AND ADVISED THE MAINT CTLR AND ENGINEER. BORESCOPED AGAIN BY TURBINE ENGINEER AND ITEM CLRED AS 'UNABLE TO FIND DEFECT.'

Narrative: ON AUG/XA/98, I WAS ASKED TO PERFORM A BORESCOPE INSPECTION OF THE #2 ENG HIGH PRESSURE TURBINE STAGE 1. THE ACFT WAS A DC10-10 WITH CF6-6 ENGS, NOSE NUMBER XYZ. WHILE VIEWING THE BLADES FROM THE TRAILING EDGE, I FOUND 1 BLADE WITH A DEFECT IN THE RADIUS APPROX MID SPAN. THE DEFECT WAS A SMALL HOLE IN THE OUTER LAYER OF THE BLADE WITH A CRACK GOING OUT OF IT UP AND AFT AT A 45 DEG ANGLE TOWARD THE TRAILING EDGE. ZZZ LINE MAINT CTL WAS NOTIFIED IN WHICH HE ASKED US TO VIDEO THE DEFECT AND SEND IT TO HIM. AFTER HE VIEWED IT HE CONTACTED THE ENGINEER AT HOME WHO WAS OVER THAT AREA OF THE ENG AND WE ALL GOT ON A CONFERENCE CALL. I DESCRIBED AGAIN WHAT I SAW AND THE CTLR CONCURRED. THE ENGINEER SAID IT SOUNDED LIKE A STRIATION OR EROSION LINE IN THE BLADE AND TO GO AHEAD AND CREATE A DEFERRED ITEM TO HAVE IT RE-EVALUATED IN 4 CYCLES. THE MAINT MANUAL REF THEY TOLD ME TO DEFER IT BY WAS FOR THIS DEFECT IN THE TIP AREA OF THE BLADE, NOT IN THE RADIUS. THE DEFERRED NUMBER WAS YXYX. IN THE COURSE OF CONVERSATION, I ALSO FOUND OUT THAT THE ENG IN THE #1 POS WAS EGT LIMITED AND WAS TO BE CHANGED (NEXT ENG OUT OF THE SHOP) ON SEP/XB/98 OR SEP/XC/98. THE NEXT NIGHT THE ENG WAS RE-BORESCOPED BY THE ENGINEER AND SIGNED OFF AS 'COULD NOT LOCATE DEFECT.' THERE WAS NO EFFORT TO CONTACT US TO DISCUSS IT, THEY HAD PICTURES OF THE DEFECT, AND STILL JUST SIGNED IT OFF. I FEEL THAT I WAS GIVEN WRONG INFO WHEN MAKING THE DEFERRED ITEM AND IT WAS INCORRECTLY DEFERRED WHEN IT LEFT WWW. I UNDERSTAND THAT ACR HAS A VERY LIMITED SUPPLY OF SPARE ENGS FOR THIS ACFT, WHICH COULD BE ANOTHER CONTRIBUTING FACTOR.

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.