Narrative:

During accomplishment of job card; drain pitot static system; leak check alternate static/auxiliary pitot system; standby airspeed/standby altimeter check; a leak was found in the auxiliary 1 pitot lines. As part of troubleshooting; lines were capped as we moved aft through the aircraft to isolate the leak. 2 leaks were found. The first leak was at an elbow fitting near the auxiliary 1 pitot tube. The elbow was not in stock and ordered. After 4 days aircraft without part; the elbow arrived. We installed it and found the auxiliary 1 pitot continued to leak out of limits. We then started isolating auxiliary 1 lines moving aft. We located a cracked t-fitting near the elevator feel computer; replaced it from local stores. The auxiliary 1 pitot line to the elevator feel computer; on the cabin side of the aft pressure bulkhead; inadvertently remained capped. We then accomplished satisfactory leak checks of the auxiliary 1 pitot system per step 5 and low range leak checks of auxiliary 1 and auxiliary 2 system per step 6. Removed and replaced elevator feel computer and connected the auxiliary 1 pitot line that was found capped at the aft pressure bulkhead. It is possible that both leak checks (steps 5 and 6 of job card) could have been successfully accomplished with the auxiliary 1 line capped at the aft pressure bulkhead. Auxiliary 1 system pressure would indicate on the standby airspeed indicator comparator is basically invisible to the test set. This may have been prevented by any or all of the following: a functional check of the elevator feel system per amm; and (added to job card) a complete visual inspection of all affected lines; a flag at any capped lines; a more complete recording of work in progress entries; and an 'ok to install' the aft galley on its install job card.

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Original NASA ASRS Text

Title: A B757-200 WAS FOUND WITH THE AUX-1 PITOT-STATIC LINE TO THE ELEVATOR FEEL COMPUTER STILL CAPPED; ON THE CABIN SIDE OF THE AFT PRESSURE BULKHEAD. THIS WAS NOT NOTICED WHEN THE AFT GALLEY WAS INSTALLED.

Narrative: DURING ACCOMPLISHMENT OF JOB CARD; DRAIN PITOT STATIC SYS; LEAK CHK ALTERNATE STATIC/AUX PITOT SYS; STANDBY AIRSPD/STANDBY ALTIMETER CHK; A LEAK WAS FOUND IN THE AUX 1 PITOT LINES. AS PART OF TROUBLESHOOTING; LINES WERE CAPPED AS WE MOVED AFT THROUGH THE ACFT TO ISOLATE THE LEAK. 2 LEAKS WERE FOUND. THE FIRST LEAK WAS AT AN ELBOW FITTING NEAR THE AUX 1 PITOT TUBE. THE ELBOW WAS NOT IN STOCK AND ORDERED. AFTER 4 DAYS ACFT WITHOUT PART; THE ELBOW ARRIVED. WE INSTALLED IT AND FOUND THE AUX 1 PITOT CONTINUED TO LEAK OUT OF LIMITS. WE THEN STARTED ISOLATING AUX 1 LINES MOVING AFT. WE LOCATED A CRACKED T-FITTING NEAR THE ELEVATOR FEEL COMPUTER; REPLACED IT FROM LCL STORES. THE AUX 1 PITOT LINE TO THE ELEVATOR FEEL COMPUTER; ON THE CABIN SIDE OF THE AFT PRESSURE BULKHEAD; INADVERTENTLY REMAINED CAPPED. WE THEN ACCOMPLISHED SATISFACTORY LEAK CHKS OF THE AUX 1 PITOT SYS PER STEP 5 AND LOW RANGE LEAK CHKS OF AUX 1 AND AUX 2 SYS PER STEP 6. REMOVED AND REPLACED ELEVATOR FEEL COMPUTER AND CONNECTED THE AUX 1 PITOT LINE THAT WAS FOUND CAPPED AT THE AFT PRESSURE BULKHEAD. IT IS POSSIBLE THAT BOTH LEAK CHKS (STEPS 5 AND 6 OF JOB CARD) COULD HAVE BEEN SUCCESSFULLY ACCOMPLISHED WITH THE AUX 1 LINE CAPPED AT THE AFT PRESSURE BULKHEAD. AUX 1 SYS PRESSURE WOULD INDICATE ON THE STANDBY AIRSPD INDICATOR COMPARATOR IS BASICALLY INVISIBLE TO THE TEST SET. THIS MAY HAVE BEEN PREVENTED BY ANY OR ALL OF THE FOLLOWING: A FUNCTIONAL CHK OF THE ELEVATOR FEEL SYS PER AMM; AND (ADDED TO JOB CARD) A COMPLETE VISUAL INSPECTION OF ALL AFFECTED LINES; A FLAG AT ANY CAPPED LINES; A MORE COMPLETE RECORDING OF WORK IN PROGRESS ENTRIES; AND AN 'OK TO INSTALL' THE AFT GALLEY ON ITS INSTALL JOB CARD.

Data retrieved from NASA's ASRS site as of May 2009 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.