Narrative:

During initial climb we experienced a red heading failure flag on both the pilot and co-pilot side pfd's and mfd's (all four screens showed the red heading flag ). As well as a red FD flag for the flight director on both attitude indicators. The heading bug was also inoperative not allowing us to select assigned headings. In addition both side mfd's went black no longer showing us our moving map display which includes our flight plan waypoints and route. The weather in our destination had been IFR most of the day and we were now only able to get heading information from our magnetic compass. Our customers had an automobile and other comfort amenities in the departure airport. We elected to divert back to the departure airport. We did not declare an emergency. Center declared an emergency for us on there own. I knew the weather at the departure airport had improved drastically over a few hours earlier and I knew a VFR visual approach could be accomplished. We descended through the high overcast layer of which the base was approximately 4400 feet. While being vectored back to the departure airport with reference only to our magnetic compass. On landing in the departure airport we weighed approximately 23;500 pounds. Which is 150 pounds more then the designed maximum landing weight of 23;350 pounds. Therefore we did an overweight landing. On runway touchdown our descent rate was only 200 feet per minute. Our customers were not disappointed and I offered to get them anything they needed while a recovery plane was on it's way to take our customers to the original destination.

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Original NASA ASRS Text

Title: A BAE-125-850XP departed a CTAF airport and during initial climb red HDG flags appeared on the Captain's and First Officer PFDs and MFD with all heading sources lost; so ATC declared an emergency and the flight returned to the departure airport.

Narrative: During initial climb we experienced a RED HDG failure flag on both the pilot and co-pilot side PFD's and MFD's (All four screens showed the RED HDG flag ). As well as a RED FD flag for the flight director on both attitude indicators. The HDG BUG was also inoperative not allowing us to select assigned Headings. In addition both side MFD's went black no longer showing us our moving map display which includes our flight plan waypoints and route. The weather in our destination had been IFR most of the day and we were now only able to get heading information from our magnetic compass. Our customers had an automobile and other comfort amenities in the departure airport. We elected to divert back to the departure airport. We did not declare an emergency. Center declared an emergency for us on there own. I knew the weather at the departure airport had improved drastically over a few hours earlier and I knew a VFR Visual approach could be accomplished. We descended through the high overcast layer of which the base was approximately 4400 feet. While being vectored back to the departure airport with reference only to our magnetic compass. On landing in the departure airport we weighed approximately 23;500 pounds. Which is 150 pounds more then the designed maximum landing weight of 23;350 pounds. Therefore we did an overweight landing. On runway touchdown our descent rate was only 200 feet per minute. Our customers were not disappointed and I offered to get them anything they needed while a recovery plane was on it's way to take our customers to the original destination.

Data retrieved from NASA's ASRS site 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.