Narrative:

Enroute on a ferry flight; we were descending thru FL400 when we had a dual heading failure. The captain and first officer had the 'heading fail' red annunciator on each pilot's pfd HSI. We completed the checklist and declared an emergency. We descended in VFR conditions and landed [without incident].

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Original NASA ASRS Text

Title: CE-560XL Captain reported loss of both his and First Officer heading information. Flight declared an emergency and diverted to a nearby airport.

Narrative: Enroute on a ferry flight; we were descending thru FL400 when we had a dual heading failure. The Captain and First Officer had the 'HDG FAIL' red annunciator on each pilot's PFD HSI. We completed the checklist and declared an emergency. We descended in VFR conditions and landed [without incident].

Data retrieved from NASA's ASRS site as of July 2013 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.