Narrative:

On the night aircraft was at and on the bill of work was to perform functional check of aileron primary mechanical control backlash. The crew that was assigned to work this aircraft started the check and could not get the ailerons to pass the check. On the afternoon I was called by our station manager and was asked if I would come in and try to do the card. When I arrived approximately XA30 hours I started performing the check with lead tech and another mechanic. I myself didn't read the card fully til we had tried a couple of times and the aileron would not pass the check. We were having to facsimile our numbers from the check to the embraer tech representative because we did not have the program to do the check. We kept getting replies that we had inconsistent data due to excessive displacement from the second measurement and on. After this I proceeded to read the card from the start and I realized that we did not have the base to apply the magnetic stand to the wing. We had been using the forks from the forklift. I then proceeded to have our parts department order the base. The base was ordered aog and we received around XH30 hours. I positioned the base on the wing according to the work card and our readings were more consistent. I had received the program from our tech representative and I put our numbers in. We were still getting inconsistent data when I again realized we were writing the numbers down wrong from the dial indicator. I was putting them down as positive when they should have been negative numbers. I also had the dial indicator set up incorrectly and was reading it incorrectly. After correcting the position of the indicator and correctly reading and writing the numbers down; we then got the correct reading from the program. I had made a comment to the supervisor earlier that I thought we may have a bad aileron PCU but that I would know more after we received the base and try the procedure again. After I put the numbers in the program and everything was good the supervisor came and asked me if the PCU was bad and I told him that it was good and that I had made mistakes on the numbers and that everything was good. When we were doing the push/pull on the ailerons another tech was using the scale pushing and pulling on the aileron; and I was reading the dial indicator and writing numbers down. The other technician wrote numbers down once or twice and then had to help on another aircraft. After we installed base on the wing and tried the procedure again he had made a comment that these numbers seemed better than before. I then showed the printout of the program and the numbers that I wrote on the work card to our inspector and asked if he needed to verify and he said that he didn't but he looked at them and said ok. The only thing he needed to look at was the torquing of the hardware on the control rods.

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Original NASA ASRS Text

Title: AN EMB140 HAD AN ENGINEERING WORK CARD TO PERFORM AN AILERON CTL BACKLASH CHK. THE PROC WAS COMPLEX; LACKED INSTRUCTIONS FOR SPECIAL TOOLS AND PROCS.

Narrative: ON THE NIGHT ACFT WAS AT AND ON THE BILL OF WORK WAS TO PERFORM FUNCTIONAL CHK OF AILERON PRIMARY MECHANICAL CTL BACKLASH. THE CREW THAT WAS ASSIGNED TO WORK THIS ACFT STARTED THE CHK AND COULD NOT GET THE AILERONS TO PASS THE CHK. ON THE AFTERNOON I WAS CALLED BY OUR STATION MGR AND WAS ASKED IF I WOULD COME IN AND TRY TO DO THE CARD. WHEN I ARRIVED APPROX XA30 HRS I STARTED PERFORMING THE CHK WITH LEAD TECH AND ANOTHER MECH. I MYSELF DIDN'T READ THE CARD FULLY TIL WE HAD TRIED A COUPLE OF TIMES AND THE AILERON WOULD NOT PASS THE CHK. WE WERE HAVING TO FAX OUR NUMBERS FROM THE CHK TO THE EMBRAER TECH REPRESENTATIVE BECAUSE WE DID NOT HAVE THE PROGRAM TO DO THE CHK. WE KEPT GETTING REPLIES THAT WE HAD INCONSISTENT DATA DUE TO EXCESSIVE DISPLACEMENT FROM THE SECOND MEASUREMENT AND ON. AFTER THIS I PROCEEDED TO READ THE CARD FROM THE START AND I REALIZED THAT WE DID NOT HAVE THE BASE TO APPLY THE MAGNETIC STAND TO THE WING. WE HAD BEEN USING THE FORKS FROM THE FORKLIFT. I THEN PROCEEDED TO HAVE OUR PARTS DEPT ORDER THE BASE. THE BASE WAS ORDERED AOG AND WE RECEIVED AROUND XH30 HRS. I POSITIONED THE BASE ON THE WING ACCORDING TO THE WORK CARD AND OUR READINGS WERE MORE CONSISTENT. I HAD RECEIVED THE PROGRAM FROM OUR TECH REPRESENTATIVE AND I PUT OUR NUMBERS IN. WE WERE STILL GETTING INCONSISTENT DATA WHEN I AGAIN REALIZED WE WERE WRITING THE NUMBERS DOWN WRONG FROM THE DIAL INDICATOR. I WAS PUTTING THEM DOWN AS POSITIVE WHEN THEY SHOULD HAVE BEEN NEGATIVE NUMBERS. I ALSO HAD THE DIAL INDICATOR SET UP INCORRECTLY AND WAS READING IT INCORRECTLY. AFTER CORRECTING THE POS OF THE INDICATOR AND CORRECTLY READING AND WRITING THE NUMBERS DOWN; WE THEN GOT THE CORRECT READING FROM THE PROGRAM. I HAD MADE A COMMENT TO THE SUPVR EARLIER THAT I THOUGHT WE MAY HAVE A BAD AILERON PCU BUT THAT I WOULD KNOW MORE AFTER WE RECEIVED THE BASE AND TRY THE PROC AGAIN. AFTER I PUT THE NUMBERS IN THE PROGRAM AND EVERYTHING WAS GOOD THE SUPVR CAME AND ASKED ME IF THE PCU WAS BAD AND I TOLD HIM THAT IT WAS GOOD AND THAT I HAD MADE MISTAKES ON THE NUMBERS AND THAT EVERYTHING WAS GOOD. WHEN WE WERE DOING THE PUSH/PULL ON THE AILERONS ANOTHER TECH WAS USING THE SCALE PUSHING AND PULLING ON THE AILERON; AND I WAS READING THE DIAL INDICATOR AND WRITING NUMBERS DOWN. THE OTHER TECHNICIAN WROTE NUMBERS DOWN ONCE OR TWICE AND THEN HAD TO HELP ON ANOTHER ACFT. AFTER WE INSTALLED BASE ON THE WING AND TRIED THE PROC AGAIN HE HAD MADE A COMMENT THAT THESE NUMBERS SEEMED BETTER THAN BEFORE. I THEN SHOWED THE PRINTOUT OF THE PROGRAM AND THE NUMBERS THAT I WROTE ON THE WORK CARD TO OUR INSPECTOR AND ASKED IF HE NEEDED TO VERIFY AND HE SAID THAT HE DIDN'T BUT HE LOOKED AT THEM AND SAID OK. THE ONLY THING HE NEEDED TO LOOK AT WAS THE TORQUING OF THE HARDWARE ON THE CTL RODS.

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.