Narrative:

I was working on a write-up to replace the blown gasket on the 13TH stage saddle duct on #1 engine. When I removed the manifold assembly, I thought I heard something drop. I told the lead mechanic about what happened, and he looked at what I had removed. He found nothing missing. I still felt uncomfortable about the situation so I told the supervisor about the situation as well. The supervisor looked at what I had removed and he found nothing missing as well. However, I just didn't feel comfortable without a borescope inspection at the engine. As a result, I asked the inspector to borescope the engine. The inspector found nothing as well. After the inspection, I reinstalled the 13TH stage saddle duct together to the best of my knowledge. When the aircraft took off from ZZZ on nov/zz/96, the #1 engine egt reading was high. The flight crew returned and landed the aircraft. When the mechanic removed the 13TH stage duct, they found the liner was missing on the 1/B side of the #1 engine. They reinstalled the liner and the aircraft was returned to service.

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Original NASA ASRS Text

Title: A B727 RETURNED TO THE FIELD DUE TO HIGH EGT ON #1 ENG CAUSED BY THE 13TH STAGE PNEUMATIC DUCT INCORRECTLY ASSEMBLED.

Narrative: I WAS WORKING ON A WRITE-UP TO REPLACE THE BLOWN GASKET ON THE 13TH STAGE SADDLE DUCT ON #1 ENG. WHEN I REMOVED THE MANIFOLD ASSEMBLY, I THOUGHT I HEARD SOMETHING DROP. I TOLD THE LEAD MECH ABOUT WHAT HAPPENED, AND HE LOOKED AT WHAT I HAD REMOVED. HE FOUND NOTHING MISSING. I STILL FELT UNCOMFORTABLE ABOUT THE SIT SO I TOLD THE SUPVR ABOUT THE SIT AS WELL. THE SUPVR LOOKED AT WHAT I HAD REMOVED AND HE FOUND NOTHING MISSING AS WELL. HOWEVER, I JUST DIDN'T FEEL COMFORTABLE WITHOUT A BORESCOPE INSPECTION AT THE ENG. AS A RESULT, I ASKED THE INSPECTOR TO BORESCOPE THE ENG. THE INSPECTOR FOUND NOTHING AS WELL. AFTER THE INSPECTION, I REINSTALLED THE 13TH STAGE SADDLE DUCT TOGETHER TO THE BEST OF MY KNOWLEDGE. WHEN THE ACFT TOOK OFF FROM ZZZ ON NOV/ZZ/96, THE #1 ENG EGT READING WAS HIGH. THE FLC RETURNED AND LANDED THE ACFT. WHEN THE MECH REMOVED THE 13TH STAGE DUCT, THEY FOUND THE LINER WAS MISSING ON THE 1/B SIDE OF THE #1 ENG. THEY REINSTALLED THE LINER AND THE ACFT WAS RETURNED TO SVC.

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.