The probable cause of the August 2013 crash of a UPS Airlines Airbus A300 freighter was the flight crew’s continuation of an unstabilized approach, as well as their failure to monitor the aircraft’s altitude when they descended below the minimum descent altitude without having the runway in sight. The U.S. National Transportation Safety Board (NTSB) announced these details at its September 9 hearing into the fatal accident at Birmingham-Shuttlesworth International Airport in Alabama. Both pilots aboard died in the crash, and a post-impact fire destroyed the aircraft.

The Board highlighted a number of factors that contributed to the accident, such as the first officer’s failure to accurately prepare the flight management system for the approach before the captain began the descent, an issue that left the autopilot unable to capture and fly the approach.

“When the flight path was not captured, the captain, without informing the first officer, changed the autopilot mode and descended at a rate that violated UPS’s stabilized approach criteria once the airplane descended below 1,000 feet above the airport elevation,” the NTSB report said.

The Board identified crew fatigue as a factor in the accident, and the Board felt lack of sleep was more of an issue related to the first officer’s performance than the captain’s. Although new Part 117 scheduling regulations apply only to scheduled passenger carriers, this UPS flight would have complied with those rules.

The Board also cited issues related to the Airbus’s terrain awareness and warning system.

The NTSB published 20 recommendations related to the accident that included 15 addressed to the FAA, two each to UPS Airlines and the Independent Pilots Association and one to Airbus.