Narrative:

On july/fri/2004, I 'bought off' the installation of an elevator autoplt servo. This installation is a rii or, required inspection item. I was acting as the inspector, not the maintenance technician. The aircraft is a dehavilland dash-8-200, flown by air carrier X. As I was looking at everything (cables, pulleys, safeties, etc..) one final time, I noticed that the cables from the servo motor went through their respective pulleys differently than what the amm illustrated. When I questioned the maintenance technician about this, he replied that it was likely the amm was incorrect and that the cables would rub together if they were on backwards. It was the end of a long night for me and I unfortunately did not pursue the matter any further. We performed the required operational tests, which passed and signed off the logbook. The next night (july/fri/2004 XA00 pm- the start of my shift) I decided to look into what I suspected was a misrigged autoplt servo. I realized upon inspecting several other dash-8's that aircraft X had a misrigged autoplt servo. (At this time I only suspected the servo cables were mis-routed through the inboard and outboard pulleys.) I did not suspect the cables were reversed. Tonight, july/sat/2004 aircraft X was back in ZZZ. (It was ron somewhere else last night.) (ron= remain overnight.) I inspected the elevator and autoplt servo cables and found them to be reversed. The airline autoplt was on MEL for pitching up with autoplt selected. Callback conversation with reporter revealed the following information: the reporter stated the maintenance manual pictorial is very poor with the cable drum shown with the left side inward and does not show cable routing on the servo drum. The reporter said the technician working the servo replacement assured the reporter the cable was spooled on the drum correctly. The reporter stated that the two tests on the adjustment and test procedures were not accomplished. Supplemental information from acn 623266: while spooling a cable drum servo, I inadvertently reversed the direction of the cables on the spool. The systems test worked fine, and the operation checks called out in the manual worked as required. A warning note could be added to the manual as an added reminder to verify the cable direction on the spool.

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Original NASA ASRS Text

Title: A DEHAVILLAND-8-200 WAS DISPATCHED IN NON-COMPLIANCE WITH THE AUTOPLT ELEVATOR SERVO DRUM CABLE SPOOLED INCORRECTLY.

Narrative: ON JULY/FRI/2004, I 'BOUGHT OFF' THE INSTALLATION OF AN ELEVATOR AUTOPLT SERVO. THIS INSTALLATION IS A RII OR, REQUIRED INSPECTION ITEM. I WAS ACTING AS THE INSPECTOR, NOT THE MAINT TECHNICIAN. THE ACFT IS A DEHAVILLAND DASH-8-200, FLOWN BY ACR X. AS I WAS LOOKING AT EVERYTHING (CABLES, PULLEYS, SAFETIES, ETC..) ONE FINAL TIME, I NOTICED THAT THE CABLES FROM THE SERVO MOTOR WENT THROUGH THEIR RESPECTIVE PULLEYS DIFFERENTLY THAN WHAT THE AMM ILLUSTRATED. WHEN I QUESTIONED THE MAINT TECHNICIAN ABOUT THIS, HE REPLIED THAT IT WAS LIKELY THE AMM WAS INCORRECT AND THAT THE CABLES WOULD RUB TOGETHER IF THEY WERE ON BACKWARDS. IT WAS THE END OF A LONG NIGHT FOR ME AND I UNFORTUNATELY DID NOT PURSUE THE MATTER ANY FURTHER. WE PERFORMED THE REQUIRED OPERATIONAL TESTS, WHICH PASSED AND SIGNED OFF THE LOGBOOK. THE NEXT NIGHT (JULY/FRI/2004 XA00 PM- THE START OF MY SHIFT) I DECIDED TO LOOK INTO WHAT I SUSPECTED WAS A MISRIGGED AUTOPLT SERVO. I REALIZED UPON INSPECTING SEVERAL OTHER DASH-8'S THAT ACFT X HAD A MISRIGGED AUTOPLT SERVO. (AT THIS TIME I ONLY SUSPECTED THE SERVO CABLES WERE MIS-ROUTED THROUGH THE INBOARD AND OUTBOARD PULLEYS.) I DID NOT SUSPECT THE CABLES WERE REVERSED. TONIGHT, JULY/SAT/2004 ACFT X WAS BACK IN ZZZ. (IT WAS RON SOMEWHERE ELSE LAST NIGHT.) (RON= REMAIN OVERNIGHT.) I INSPECTED THE ELEVATOR AND AUTOPLT SERVO CABLES AND FOUND THEM TO BE REVERSED. THE AIRLINE AUTOPLT WAS ON MEL FOR PITCHING UP WITH AUTOPLT SELECTED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE MAINT MANUAL PICTORIAL IS VERY POOR WITH THE CABLE DRUM SHOWN WITH THE LEFT SIDE INWARD AND DOES NOT SHOW CABLE ROUTING ON THE SERVO DRUM. THE RPTR SAID THE TECHNICIAN WORKING THE SERVO REPLACEMENT ASSURED THE RPTR THE CABLE WAS SPOOLED ON THE DRUM CORRECTLY. THE RPTR STATED THAT THE TWO TESTS ON THE ADJUSTMENT AND TEST PROCS WERE NOT ACCOMPLISHED. SUPPLEMENTAL INFO FROM ACN 623266: WHILE SPOOLING A CABLE DRUM SERVO, I INADVERTENTLY REVERSED THE DIRECTION OF THE CABLES ON THE SPOOL. THE SYSTEMS TEST WORKED FINE, AND THE OP CHKS CALLED OUT IN THE MANUAL WORKED AS REQUIRED. A WARNING NOTE COULD BE ADDED TO THE MANUAL AS AN ADDED REMINDER TO VERIFY THE CABLE DIRECTION ON THE SPOOL.

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.