Narrative:

We were told to line up and wait runway 13. As I finished the check list we realized both sides 'red box magnetic and FD' were flashing. I immediately exited the runway and; as soon as we did; everything went back to normal without doing anything. We taxied for a few more moments then tower asked the reason for our abort. I explained that there was no abort but simply decided to exit because of the pfd red flags. I then told him that the problem went away and we were ready so he cleared us back to 13. Shortly after takeoff both red flags came back and were intermittent between the left side and the right side. Several seconds later the red flags went away but we both then had yellow 'heading' warnings flashing. We were flying 180 degrees on the LGA2 SID; whitestone climb. I then looked at my DME; it was reading 4.3 from lga; the flying pilot immediately initiated the left turn and at the same moment the departure controller told us to turn left to 360 degrees which we did. He then told us we had gone through the distance [a left turn to 040 degrees is required at 2.5 DME]. During the turn he gave us a different frequency to contact. I told the second controller that we had our heading capabilities degraded. The yellow heading kept flashing for a few minutes and then went away. We landed at our destination airport; contacted maintenance control and submitted the write up. During the event we both got distracted while trying to figure what was happening and especially which heading indication to trust. In a perfect world I would say that during an emergency of any sort the priority is to fly the airplane which we did; but not knowing which heading indicator to look at or to trust was definitely a challenge..

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Original NASA ASRS Text

Title: A BE400 Flight Crew was confronted with compass system anomalies that appeared momentarily prior to takeoff but; after exiting the runway; went away; only to return after the subsequent liftoff. ATC provided assistance in the form of headings. The warnings later disappeared.

Narrative: We were told to line up and wait Runway 13. As I finished the check list we realized both sides 'Red box MAG and FD' were flashing. I immediately exited the runway and; as soon as we did; everything went back to normal without doing anything. We taxied for a few more moments then tower asked the reason for our abort. I explained that there was no abort but simply decided to exit because of the PFD red flags. I then told him that the problem went away and we were ready so he cleared us back to 13. Shortly after takeoff both red flags came back and were intermittent between the left side and the right side. Several seconds later the red flags went away but we both then had yellow 'HDG' warnings flashing. We were flying 180 degrees on the LGA2 SID; Whitestone Climb. I then looked at my DME; it was reading 4.3 from LGA; the flying pilot immediately initiated the left turn and at the same moment the departure controller told us to turn left to 360 degrees which we did. He then told us we had gone through the distance [a left turn to 040 degrees is required at 2.5 DME]. During the turn he gave us a different frequency to contact. I told the second controller that we had our heading capabilities degraded. The Yellow HDG kept flashing for a few minutes and then went away. We landed at our destination airport; contacted maintenance control and submitted the write up. During the event we both got distracted while trying to figure what was happening and especially which heading indication to trust. In a perfect world I would say that during an emergency of any sort the priority is to fly the airplane which we did; but not knowing which heading indicator to look at or to trust was definitely a challenge..

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.