Narrative:

I previewed the task fairly quickly to look for hidden operational checks and also to get an idea of what I was getting into. Since I was only slightly familiar with the crj; I had to look up some of the sub tasks like 'standard aircraft configuration for maintenance' where I learned that the aircraft needed to be grounded before maintenance. Although it had been in the hangar most of the night; nobody had grounded it yet. So I found a ground wire and attached it correctly. I ordered the tools out; and questioned two nearby mechanics who knew the airplane better if they had performed the engineering order before. They had not. The situation actually was that it wasn't until this point in the task that my co-worker joined me and explained that she had been asked to assist me in the task. So I had her read out the task to me while I performed the maintenance. We went slowly. Pulling the circuit breakers; installing the 'do not touch' red tape on the control column wheels; and then removing the right wheel bin; which was first read out to me as; 'remove the right main landing gear wheel pin.' this didn't sound right considering that we were working on the ailerons. So upon closer examination found it to read; 'remove the right main landing gear bin;' which I partially did but did not fully remove it. The bin can be slid under the back of the wing to fuselage fairing only if the main landing gear strut is newly serviced. In this case it didn't slide all the way out but only partially out. However; I had enough space to twist my way up and gain access to insert the rig pin and reach the aileron servo but couldn't see it very well. So I chose to leave the wheel bin in that awkward; but doable position. Next I installed the rig pin and proceeded to prepare for the functional check. I had my co-worker read out the entire functional check at first and visualized it as she read it. The only thing I couldn't visualize is what the output shaft of the aileron servo mount was. So I asked my co-worker who pointed to an illustration and I saw a regular six sided nut on the illustration that I thought she was pointing to which I also identified on the actual device on the aircraft. I did; however; have to strain a little to see the nut clearly. The aileron slip clutch is tucked away in a corner of the right gear wheel bay and access is limited by a few hydraulic lines and the side that you have to access is all the way in the corner. So I had to work by feel. As I checked the breakaway torque on the adjustment nut rather than the output shaft it did not feel right to me. So going back to the book and looking at the picture closer myself I learned that I was turning the wrong thing. Deciding to get better access; I partially jacked up the right main gear enough to pull the wheel bin out. Then with a flashlight and mirror I examined the back of the slip clutch and found that the safety wire was broken on the adjusting nut and found the square drive output shaft. Now with better access I checked the breakaway torque. Found it to be out of adjustment so adjusted it according to the manual. The final step in the task is to safety the slip clutch; written as 'safety the adjustment nut with lock wire.' there is neither a note nor a picture depicting where the safety wire should be secured to. So I chose the most likely location and also where I thought the original safety wire had been fastened to. While working on the safety job; my co-worker was in the wheel well with me very close and trying to see what I was doing and holding her flashlight for me. Although I wanted the new mechanic to be close to the action; I was awkward in the small space; so I asked her to go do a small task. She finished that up quickly and then returned back to the wheel well where she stayed the remainder of the job. So I just let her stay while I finished up the safety job. From where I had pulled off the broken safety wire; it looked like it had been safetied to one of the mount screws. Finding it easier to safety to the mount screw's support ring; I safetiedit to the support ring. Again; I thought that it was equal to the former safety job. I did not notice that one part was a moving part and the other was stationary. I might have noticed this if a number of factors had been different like better visibility; more specifics in the manual on where to safety the adjustment nut; or if I had removed the original safety wire. A freedom of movement check would have quickly shown my error. Also; the incorrect safety would probably have been picked up by another mechanic checking over my work. Finally; I could have requested to work alone on the project by recognizing the extra distraction of a new mechanic.callback conversation with reporter revealed the following information: the reporter stated the engineering job card did not address the correct installation of the safety wire; other than remove and safety the adjustment nut with lock wire. No pictorial was available of the correct safety wire installation on the adjustment nut. The engineering note made no mention of an autoplt functional check. Reporter stated this job card and the maintenance manual need revision.

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Original NASA ASRS Text

Title: A CRJ700 TECHNICIAN EXPERIENCED DIFFICULTY ADJUSTING THE AILERON SERVO SLIP CLUTCH; RESULTING IN INCORRECT SAFETY WIRING ON THE ADJUSTING NUT.

Narrative: I PREVIEWED THE TASK FAIRLY QUICKLY TO LOOK FOR HIDDEN OPERATIONAL CHKS AND ALSO TO GET AN IDEA OF WHAT I WAS GETTING INTO. SINCE I WAS ONLY SLIGHTLY FAMILIAR WITH THE CRJ; I HAD TO LOOK UP SOME OF THE SUB TASKS LIKE 'STANDARD ACFT CONFIGURATION FOR MAINT' WHERE I LEARNED THAT THE ACFT NEEDED TO BE GNDED BEFORE MAINT. ALTHOUGH IT HAD BEEN IN THE HANGAR MOST OF THE NIGHT; NOBODY HAD GNDED IT YET. SO I FOUND A GND WIRE AND ATTACHED IT CORRECTLY. I ORDERED THE TOOLS OUT; AND QUESTIONED TWO NEARBY MECHANICS WHO KNEW THE AIRPLANE BETTER IF THEY HAD PERFORMED THE ENGINEERING ORDER BEFORE. THEY HAD NOT. THE SITUATION ACTUALLY WAS THAT IT WASN'T UNTIL THIS POINT IN THE TASK THAT MY CO-WORKER JOINED ME AND EXPLAINED THAT SHE HAD BEEN ASKED TO ASSIST ME IN THE TASK. SO I HAD HER READ OUT THE TASK TO ME WHILE I PERFORMED THE MAINT. WE WENT SLOWLY. PULLING THE CIRCUIT BREAKERS; INSTALLING THE 'DO NOT TOUCH' RED TAPE ON THE CTL COLUMN WHEELS; AND THEN REMOVING THE R WHEEL BIN; WHICH WAS FIRST READ OUT TO ME AS; 'REMOVE THE R MAIN LNDG GEAR WHEEL PIN.' THIS DIDN'T SOUND RIGHT CONSIDERING THAT WE WERE WORKING ON THE AILERONS. SO UPON CLOSER EXAMINATION FOUND IT TO READ; 'REMOVE THE R MAIN LNDG GEAR BIN;' WHICH I PARTIALLY DID BUT DID NOT FULLY REMOVE IT. THE BIN CAN BE SLID UNDER THE BACK OF THE WING TO FUSELAGE FAIRING ONLY IF THE MAIN LNDG GEAR STRUT IS NEWLY SERVICED. IN THIS CASE IT DIDN'T SLIDE ALL THE WAY OUT BUT ONLY PARTIALLY OUT. HOWEVER; I HAD ENOUGH SPACE TO TWIST MY WAY UP AND GAIN ACCESS TO INSERT THE RIG PIN AND REACH THE AILERON SERVO BUT COULDN'T SEE IT VERY WELL. SO I CHOSE TO LEAVE THE WHEEL BIN IN THAT AWKWARD; BUT DOABLE POSITION. NEXT I INSTALLED THE RIG PIN AND PROCEEDED TO PREPARE FOR THE FUNCTIONAL CHK. I HAD MY CO-WORKER READ OUT THE ENTIRE FUNCTIONAL CHK AT FIRST AND VISUALIZED IT AS SHE READ IT. THE ONLY THING I COULDN'T VISUALIZE IS WHAT THE OUTPUT SHAFT OF THE AILERON SERVO MOUNT WAS. SO I ASKED MY CO-WORKER WHO POINTED TO AN ILLUSTRATION AND I SAW A REGULAR SIX SIDED NUT ON THE ILLUSTRATION THAT I THOUGHT SHE WAS POINTING TO WHICH I ALSO IDENTIFIED ON THE ACTUAL DEVICE ON THE ACFT. I DID; HOWEVER; HAVE TO STRAIN A LITTLE TO SEE THE NUT CLRLY. THE AILERON SLIP CLUTCH IS TUCKED AWAY IN A CORNER OF THE R GEAR WHEEL BAY AND ACCESS IS LIMITED BY A FEW HYD LINES AND THE SIDE THAT YOU HAVE TO ACCESS IS ALL THE WAY IN THE CORNER. SO I HAD TO WORK BY FEEL. AS I CHKED THE BREAKAWAY TORQUE ON THE ADJUSTMENT NUT RATHER THAN THE OUTPUT SHAFT IT DID NOT FEEL RIGHT TO ME. SO GOING BACK TO THE BOOK AND LOOKING AT THE PICTURE CLOSER MYSELF I LEARNED THAT I WAS TURNING THE WRONG THING. DECIDING TO GET BETTER ACCESS; I PARTIALLY JACKED UP THE R MAIN GEAR ENOUGH TO PULL THE WHEEL BIN OUT. THEN WITH A FLASHLIGHT AND MIRROR I EXAMINED THE BACK OF THE SLIP CLUTCH AND FOUND THAT THE SAFETY WIRE WAS BROKEN ON THE ADJUSTING NUT AND FOUND THE SQUARE DRIVE OUTPUT SHAFT. NOW WITH BETTER ACCESS I CHKED THE BREAKAWAY TORQUE. FOUND IT TO BE OUT OF ADJUSTMENT SO ADJUSTED IT ACCORDING TO THE MANUAL. THE FINAL STEP IN THE TASK IS TO SAFETY THE SLIP CLUTCH; WRITTEN AS 'SAFETY THE ADJUSTMENT NUT WITH LOCK WIRE.' THERE IS NEITHER A NOTE NOR A PICTURE DEPICTING WHERE THE SAFETY WIRE SHOULD BE SECURED TO. SO I CHOSE THE MOST LIKELY LOCATION AND ALSO WHERE I THOUGHT THE ORIGINAL SAFETY WIRE HAD BEEN FASTENED TO. WHILE WORKING ON THE SAFETY JOB; MY CO-WORKER WAS IN THE WHEEL WELL WITH ME VERY CLOSE AND TRYING TO SEE WHAT I WAS DOING AND HOLDING HER FLASHLIGHT FOR ME. ALTHOUGH I WANTED THE NEW MECHANIC TO BE CLOSE TO THE ACTION; I WAS AWKWARD IN THE SMALL SPACE; SO I ASKED HER TO GO DO A SMALL TASK. SHE FINISHED THAT UP QUICKLY AND THEN RETURNED BACK TO THE WHEEL WELL WHERE SHE STAYED THE REMAINDER OF THE JOB. SO I JUST LET HER STAY WHILE I FINISHED UP THE SAFETY JOB. FROM WHERE I HAD PULLED OFF THE BROKEN SAFETY WIRE; IT LOOKED LIKE IT HAD BEEN SAFETIED TO ONE OF THE MOUNT SCREWS. FINDING IT EASIER TO SAFETY TO THE MOUNT SCREW'S SUPPORT RING; I SAFETIEDIT TO THE SUPPORT RING. AGAIN; I THOUGHT THAT IT WAS EQUAL TO THE FORMER SAFETY JOB. I DID NOT NOTICE THAT ONE PART WAS A MOVING PART AND THE OTHER WAS STATIONARY. I MIGHT HAVE NOTICED THIS IF A NUMBER OF FACTORS HAD BEEN DIFFERENT LIKE BETTER VISIBILITY; MORE SPECIFICS IN THE MANUAL ON WHERE TO SAFETY THE ADJUSTMENT NUT; OR IF I HAD REMOVED THE ORIGINAL SAFETY WIRE. A FREEDOM OF MOVEMENT CHK WOULD HAVE QUICKLY SHOWN MY ERROR. ALSO; THE INCORRECT SAFETY WOULD PROBABLY HAVE BEEN PICKED UP BY ANOTHER MECHANIC CHKING OVER MY WORK. FINALLY; I COULD HAVE REQUESTED TO WORK ALONE ON THE PROJECT BY RECOGNIZING THE EXTRA DISTRACTION OF A NEW MECHANIC.CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE ENGINEERING JOB CARD DID NOT ADDRESS THE CORRECT INSTALLATION OF THE SAFETY WIRE; OTHER THAN REMOVE AND SAFETY THE ADJUSTMENT NUT WITH LOCK WIRE. NO PICTORIAL WAS AVAILABLE OF THE CORRECT SAFETY WIRE INSTALLATION ON THE ADJUSTMENT NUT. THE ENGINEERING NOTE MADE NO MENTION OF AN AUTOPLT FUNCTIONAL CHK. RPTR STATED THIS JOB CARD AND THE MAINT MANUAL NEED REVISION.

Data retrieved from NASA's ASRS site as of January 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.