Narrative:

During climb out #1 ahrs failed. I transferred flight controls to the first officer who was the pilot monitoring; until that time. We had just departed ZZZ and reached 9000 feet. We were cleared up to 12000 during the start of the failure and asked to remain at 9000 while we sorted out the problem; which was approved. We called dispatch and spoke with maintenance control who recommended we return to ZZZ. We returned to the field; followed by a normal landing and arrival to the gate; where the passengers were deplaned and the flight was canceled. An FAA inspector was in the jump seat and witnessed to entire event. My flight instruments starting to give mixed information. Then the message was displayed on the 800 panel. Ahrs failed in solid IMC conditions.

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Original NASA ASRS Text

Title: A DHC8-300 Captain's AHRS failed shortly after takeoff. The aircraft returned to the departure airport and the flight was cancelled.

Narrative: During climb out #1 AHRS failed. I transferred flight controls to the First Officer who was the Pilot Monitoring; until that time. We had just departed ZZZ and reached 9000 feet. We were cleared up to 12000 during the start of the failure and asked to remain at 9000 while we sorted out the problem; which was approved. We called Dispatch and spoke with Maintenance Control who recommended we return to ZZZ. We returned to the field; followed by a normal landing and arrival to the gate; where the passengers were deplaned and the flight was canceled. An FAA inspector was in the jump seat and witnessed to entire event. My flight instruments starting to give mixed information. Then the message was displayed on the 800 panel. AHRS failed in solid IMC conditions.

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.