Narrative:

While cruising at FL330 just north of dib VOR on an assigned heading of approximately 060 degrees ZOB cleared us direct slt VOR. We needed to turn right to a heading of about 120 degrees magnetic. Center told us to stop our turn and gave us an immediate descent to FL310. They informed us that we were heading approximately 180 degrees. I requested a no gyroscope turn for an initial heading to slt VOR until I could get our compasses straightened out. I talked with a ZOB shift supervisor on the phone who had reviewed the tape of the situation. I assured him that I had entered the compass failure problem in the aircraft maintenance log for corrective action. He stated that there had been no critical traffic conflict and that no incident report would be filed. Callback conversation with reporter revealed the following information: the reporter stated he was flying an MD81. A glass cockpit or IRS system does not exist on the model. The problem was determined to be the wrong kind of screws were installed in the wing, non ferrous versus ferrous metal screws.

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Original NASA ASRS Text

Title: THE RPTR TURNED TO AN INDICATED HEADING OF 120 DEGS WHICH WAS ACCORDING TO CTR ABOUT 180 DEGS. THE COMPASS WAS IN ERROR AND THE RPTR REQUESTED A NO GYROSCOPE TURN FROM THE CTLR.

Narrative: WHILE CRUISING AT FL330 JUST N OF DIB VOR ON AN ASSIGNED HDG OF APPROX 060 DEGS ZOB CLRED US DIRECT SLT VOR. WE NEEDED TO TURN R TO A HDG OF ABOUT 120 DEGS MAGNETIC. CTR TOLD US TO STOP OUR TURN AND GAVE US AN IMMEDIATE DSCNT TO FL310. THEY INFORMED US THAT WE WERE HEADING APPROX 180 DEGS. I REQUESTED A NO GYROSCOPE TURN FOR AN INITIAL HDG TO SLT VOR UNTIL I COULD GET OUR COMPASSES STRAIGHTENED OUT. I TALKED WITH A ZOB SHIFT SUPVR ON THE PHONE WHO HAD REVIEWED THE TAPE OF THE SIT. I ASSURED HIM THAT I HAD ENTERED THE COMPASS FAILURE PROB IN THE ACFT MAINT LOG FOR CORRECTIVE ACTION. HE STATED THAT THERE HAD BEEN NO CRITICAL TFC CONFLICT AND THAT NO INCIDENT RPT WOULD BE FILED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED HE WAS FLYING AN MD81. A GLASS COCKPIT OR IRS SYS DOES NOT EXIST ON THE MODEL. THE PROB WAS DETERMINED TO BE THE WRONG KIND OF SCREWS WERE INSTALLED IN THE WING, NON FERROUS VERSUS FERROUS METAL SCREWS.

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.