Mechanic inadvertently signed off 2 sense lines as having been reconnected during an engine change. ...

Attributes
ACN	233127
Time
Date	199302
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : msp
State Reference	MN
Altitude	agl bound lower : 0 agl bound upper : 0
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	ground : preflight
Person 1
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
ASRS Report	233127
Person 2
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
ASRS Report	233137
Events
Anomaly	aircraft equipment problem : critical non adherence : far non adherence : published procedure
Independent Detector	other other : unspecified
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

I was involved in an engine change. The process I signed data card off for 2 sense lines that were not hooked up. The aircraft left msp, flew to san diego, where the problem was found and resolved. I was informed of the problem the next day. The data sign-off I signed was for a clamp I had installed but also included the 2 sense lines involved. Although I did not hook up the lines I visually checked them at the firewall which is the normal connections on an engine change. They were found disconnected at the valve instead, which I did not check. Supplemental information from acn 233137: air engine #1 bleed fault. Found pneumatic muscle pressure line from prv to tlt and sense line from upstream side of prv to tlt both disconnected. Both valves operated correctly after lines were reconnected. Further problems of this nature can be avoided by the use of a step-by-step checklist of items that are disconnected during engine replacement and that must be reconnected/installed, with inspector stamp blocks for each item. Present paperwork shows only a general description for inspection sign-off and mechanic sign-off.

Original NASA ASRS Text

Title: MECH INADVERTENTLY SIGNED OFF 2 SENSE LINES AS HAVING BEEN RECONNECTED DURING AN ENG CHANGE. ACFT WAS FLOWN ON A TRIP WITH BOTH LINES DISCONNECTED.

Narrative: I WAS INVOLVED IN AN ENG CHANGE. THE PROCESS I SIGNED DATA CARD OFF FOR 2 SENSE LINES THAT WERE NOT HOOKED UP. THE ACFT LEFT MSP, FLEW TO SAN DIEGO, WHERE THE PROB WAS FOUND AND RESOLVED. I WAS INFORMED OF THE PROB THE NEXT DAY. THE DATA SIGN-OFF I SIGNED WAS FOR A CLAMP I HAD INSTALLED BUT ALSO INCLUDED THE 2 SENSE LINES INVOLVED. ALTHOUGH I DID NOT HOOK UP THE LINES I VISUALLY CHKED THEM AT THE FIREWALL WHICH IS THE NORMAL CONNECTIONS ON AN ENG CHANGE. THEY WERE FOUND DISCONNECTED AT THE VALVE INSTEAD, WHICH I DID NOT CHK. SUPPLEMENTAL INFO FROM ACN 233137: AIR ENG #1 BLEED FAULT. FOUND PNEUMATIC MUSCLE PRESSURE LINE FROM PRV TO TLT AND SENSE LINE FROM UPSTREAM SIDE OF PRV TO TLT BOTH DISCONNECTED. BOTH VALVES OPERATED CORRECTLY AFTER LINES WERE RECONNECTED. FURTHER PROBS OF THIS NATURE CAN BE AVOIDED BY THE USE OF A STEP-BY-STEP CHKLIST OF ITEMS THAT ARE DISCONNECTED DURING ENG REPLACEMENT AND THAT MUST BE RECONNECTED/INSTALLED, WITH INSPECTOR STAMP BLOCKS FOR EACH ITEM. PRESENT PAPERWORK SHOWS ONLY A GENERAL DESCRIPTION FOR INSPECTION SIGN-OFF AND MECH SIGN-OFF.

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.

Mechanic inadvertently signed off 2 sense lines as having been reconnected during an engine change. Aircraft was flown on a trip with both lines disconnected.