As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BZN- ON FLIGHT 2381 TAKEOFF WARNING HORN SOUNDS AS POWER LEVERS/TORQUE REACHED 50 PERCENT TORQUE. ABORTED TAKEOFF AT 79 KNTS. AUTOFEATHER FAILED TO ARM. COMPLIED WITH AUTOFEATHER TEST, GROUND RAN AIRCRAFT. NO PARTS REPLACED. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.