Narrative:

On an IFR flight plan. Upon contact with approach; I was given vector of 270 degrees. I entered IMC with the autoplt flying the heading bug on the directional gyro. After a few moments; I was told by approach that I was nearing terrain and was asked what heading I was flying. The directional gyro was indicating 270 degrees; but approach was tracking me on an approximately 360 degree heading. It was then I noticed the directional gyro; compass and GPS did not match heading information. The directional gyro card had stuck in place and was frozen. Without ground reference and conflicting instruments; I disengaged the autoplt and began a turn to what I thought was 180 degrees; which was the heading given by ATC. ATC then informed me I was 'holding up air traffic at another airport.' when I exited IMC I was able to track the heading given to me by ATC and made an ILS approach; in visual conditions. Although ATC did not ask me to call; I spoke with the supervisor at the TRACON and explained what had happened. The aircraft had recently been fitted with a new directional gyro and avionics; which until this incident appeared to be working. The aircraft is now being refitted with a new directional gyro. The directional gyro in question had been yellow tagged (8130) and returned to service prior to installation in the aircraft.

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Original NASA ASRS Text

Title: A BEECH 95 ON AUTOPLT IS ALERTED BY APCH CTL OF TERRAIN. DISCOVERED AIRPLANE 90 DEGS OFF COURSE DUE TO FAILED DIRECTIONAL GYRO.

Narrative: ON AN IFR FLT PLAN. UPON CONTACT WITH APCH; I WAS GIVEN VECTOR OF 270 DEGS. I ENTERED IMC WITH THE AUTOPLT FLYING THE HDG BUG ON THE DIRECTIONAL GYRO. AFTER A FEW MOMENTS; I WAS TOLD BY APCH THAT I WAS NEARING TERRAIN AND WAS ASKED WHAT HDG I WAS FLYING. THE DIRECTIONAL GYRO WAS INDICATING 270 DEGS; BUT APCH WAS TRACKING ME ON AN APPROX 360 DEG HDG. IT WAS THEN I NOTICED THE DIRECTIONAL GYRO; COMPASS AND GPS DID NOT MATCH HDG INFO. THE DIRECTIONAL GYRO CARD HAD STUCK IN PLACE AND WAS FROZEN. WITHOUT GND REF AND CONFLICTING INSTS; I DISENGAGED THE AUTOPLT AND BEGAN A TURN TO WHAT I THOUGHT WAS 180 DEGS; WHICH WAS THE HDG GIVEN BY ATC. ATC THEN INFORMED ME I WAS 'HOLDING UP AIR TFC AT ANOTHER ARPT.' WHEN I EXITED IMC I WAS ABLE TO TRACK THE HDG GIVEN TO ME BY ATC AND MADE AN ILS APCH; IN VISUAL CONDITIONS. ALTHOUGH ATC DID NOT ASK ME TO CALL; I SPOKE WITH THE SUPVR AT THE TRACON AND EXPLAINED WHAT HAD HAPPENED. THE ACFT HAD RECENTLY BEEN FITTED WITH A NEW DIRECTIONAL GYRO AND AVIONICS; WHICH UNTIL THIS INCIDENT APPEARED TO BE WORKING. THE ACFT IS NOW BEING REFITTED WITH A NEW DIRECTIONAL GYRO. THE DIRECTIONAL GYRO IN QUESTION HAD BEEN YELLOW TAGGED (8130) AND RETURNED TO SVC PRIOR TO INSTALLATION IN THE ACFT.

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.