What was found
DURING THE TAXI FOR TAKEOFF, A NUMBER ONE ATTITUDE HEADING REFERENCE UNIT (AHRS) FAILURE WARNING MESSAGE ILLUMINATED. THE AIRCRAFT RETURNED TO THE GATE. OUTSTATION MAINTENANCE INSPECTED AND APPROVED THE AIRCRAFT FOR A FERRY FLIGHT TO PIT. THE FERRY WAS EXECUTED WITHOUT ANY PROBLEMS. PIT MAINTENANCE INSPECTED AND REPLACED THE NUMBER ONE AHRS UNIT, IN ACCORDANCE WITH DORNIER MAINTENANCE MANUAL 34-21-10. OPERATIONAL CHECKS WERE COMPLETED.