The final report into a fatal crash of a UPS cargo plane in Dubai in 2010 has made a number of safety recommendations after identifying a blaze linked to lithium batteries as the cause.
The UAE's General Civil Aviation Authority (GCAA) said the Boeing 747-400 Freighter crash in which two pilots were killed was caused by a large fire that "auto-ignited" and spread due to "inadequate" fire suppression systems.
At the time, Al Qaeda's Yemen based wing, Al Qaeda in the Arabian Peninsula (AQAP), claimed responsibility for the crash but no evidence of explosives was found on board.
The report said: "A large fire developed in palletised cargo on the main deck at or near pallet positions 4 or 5, in Fire Zone 3, consisting of consignments of mixed cargo including a significant number of lithium type batteries and other combustible materials. The fire escalated rapidly into a catastrophic uncontained fire."
It added that the fire "directly affected the independent critical systems necessary for crew survivability".
"Nearly three years following this tragic accident, UPS pilots welcome the release of this final report," said Independent Pilots Association (IPA) president Robert Travis.
"Some of the GCAA's recommendations are already being addressed by a joint company and pilot union group, the IPA/UPS Safety Task Force, created shortly after the accident," he said.
Travis added that the union has worked with UPS to design, build, test and demonstrate an active fire suppression system capable of suppressing and containing a fire for up to four hours.
"We encourage the FAA and UPS to move quickly and deliberately in approving and fully implementing this new technology," said Travis.
"We tragically lost two of our best pilots in the Dubai crash. As UPS pilots, we are determined to do everything in our power to minimise the risk associated with on-board smoke and fire events," said Travis.
"This includes proper regulations governing the carriage of hazardous materials including lithium batteries."
Twenty two minutes into the flight, at approximately 32,000 feet, the crew advised Bahrain Area East Air Traffic Control that there was an indication of an on-board fire.
Less than three minutes after the first warning to the crew, the fire resulted in severe damage to flight control systems and caused the upper deck and cockpit to fill with continuous smoke.