Narrative:

A mooney was on an overflight at 7;000. The aircraft was handed off to the next approach facility and then the previous approach facility called the second approach facility regarding the aircraft that all of sudden was turning northbound (almost a 180 degree turn) for no apparent reason. At this time I also noticed the turn around and was trying to ascertain from the pilot on what exactly was happening and if assistance was needed and/or if he wanted to continue. The pilot was having problems maintaining headings and altitudes. After about 4-5 minutes of trying to get information out of him and pointing out the aircraft to multiple facilities; it appears that the cause of the event was an electrical compass failure.

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Original NASA ASRS Text

Title: Controller described an unanticipated turn by an IFR aircraft requiring numerous coordination efforts; later advised the aircraft experienced an electrical compass failure.

Narrative: A Mooney was on an overflight at 7;000. The aircraft was handed off to the next Approach facility and then the previous Approach facility called the second Approach facility regarding the aircraft that all of sudden was turning northbound (almost a 180 degree turn) for no apparent reason. At this time I also noticed the turn around and was trying to ascertain from the pilot on what exactly was happening and if assistance was needed and/or if he wanted to continue. The pilot was having problems maintaining headings and altitudes. After about 4-5 minutes of trying to get information out of him and pointing out the aircraft to multiple facilities; it appears that the cause of the event was an electrical compass failure.

Data retrieved from NASA's ASRS site as of April 2012 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.