Pilot fatigue and aircraft approaches were among the issues raised in a US National Transportation Safety Board (NTSB) hearing today into the fatal crash of a UPS Airbus A300-600 on 14 August 2013.
The aircraft crashed while on approach to Birmingham-Shuttlesworth International airport in Alabama after originating in Louisville, Kentucky.
“We have not identified any anomalies with the airplane, systems, or enhanced ground proximity warning,” says Daniel Bower, the NTSB’s senior aviation accident investigator in testimony.
The hearing focused on the pilots’ actions as they used a non-precision localiser approach to land at the airport while its main runway was closed, as well as pilot fatigue and flight dispatch procedures.
As the flight prepared to land, the aircraft’s captain was flying and the first officer was monitoring the flight. Clouds were present 1,000ft (305m) above the ground and the sky was overcast with calm winds and 10 miles (16.1km) visibility.
Because the airport’s 11,998ft main runway 6/24 was closed for repairs, the aircraft captain prepared for a non-precision localiser approach into the 7,099ft long runway 18. Non-precision approaches are uncommon for UPS pilots.
The main runway re-opened minutes after the crash.
At about 04:47 local time, the flight crew received the sound of a “sink rate” alert from the aircraft’s enhanced ground proximity warning system (EGPWS) before the aircraft hit trees on approach to the airport.
That alert came on at about 235ft while the aircraft was descending at a rate of 1,536ft/min (7.8 m/s).The pilot started reducing speed a second later, which reached 450ft/min. A second before the initial impact, the pilot disconnected the autopilot. The minimum altitude where the pilots would have had to initiate a go-around is at 1,200ft above sea level, or about 500ft above the ground at the airport, says Bower.
About seven seconds later, the aircraft hit trees and terrain about 1.93km from the end of the runway and subsequently caught fire. Both pilots died in the crash.
The first officer made a call out at 1,000ft but did not make further call outs required by the aircraft operating manual after that time, the investigative report shows.
The crew could not intercept the landing profile they loaded because it was not sequenced properly, the investigation board found. Several parameters on the aircraft equipment would have indicated this to the crew, including the autopilot turning off, says William Andrew Middleton Jr., a UPS pilot.
Fatigue was a main focus of the hearing, and cockpit voice recorder transcripts show that the pilots mentioned that they have encountered feeling tired on trips. Data from the hearing showed that UPS’ pilots called off duty due to fatigue issues on 138 flights in 2013. Of those calls, 38 were related to flying on the Airbus A300, or nearly 28%. The main reason for the calls on that aircraft type was how the schedule was constructed, says Lauri Esposito, a UPS first officer who flies Boeing 757 and 767 aircraft.
The NTSB will use the facts of the hearing to determine the probable cause of the accident when the investigation is complete.