The former head of security for the United States’ Federal Aviation Administration insists that rather than portraying the crew of the missing Malaysian Airlines Flight 370 as saboteurs, the pilots struggled heroically to save their aircraft until overcome by smoke from a catastrophic cargo fire.

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Billie Vincent who served as the FAA’s civil aviation security chief played a key policy and crisis management role in the handling of all hijackings of US aircraft in the 1980s. He was also in charge of the agency’s armed Federal Air Marshals and served as an expert witness in the trial of the Pan Am 103 terrorist bombing.

After leaving the FAA he led an international consulting firm which was contracted in the 1990s to design and implement the security system of Malaysia’s Kuala Lumpur International Airport where Flight 370, carrying 227 passengers and 12 crew, started its journey at 12.41 am on March 8 before disappearing from civilian radar en route to Beijing at 1.21 am.

Officials in Malaysia claim that, based on ‘pings’ sent from the aircraft to an Inmarsat satellite, the aircraft was deliberately diverted and may have flown as far north as Central Asia or south over the Indian Ocean. They suspect that someone on board the aircraft first disabled one of its communications systems – the Aircraft and Communications Addressing and Reporting System (ACARS) around 40 minutes after takeoff before switching off the aircraft’s transponder in a systematic effort to render the aircraft invisible to air traffic surveillance.

Speaking exclusively to Air Traffic Management, Vincent dismisses the likelihood of a bomb being detonated on board which would have ruptured the pressure hull of the aircraft citing the fact that the aircraft was tracked by a series of satellite ‘pings’. That would indicate that Flight MH370 flew for up to seven more hours which would not have been possible if it had been compromised.

“The data released thus far most likely points to a problem with hazardous materials. This scenario begins with the eruption of hazardous materials within the cargo hold – either improperly packaged or illegally shipped – or both,” says Vincent.

In his view, a fire which started in the cargo hold progressively and serially destroyed the aircraft’s communications systems; toxic fumes quickly overwhelmed the passenger cabin and the cockpit where at least one of the flight crew managed to don an oxygen mask allowing them to turn the aircraft back to Kuala Lumpur.

Flight 370 is reported to have climbed to 45,000ft which Vincent believes could have been due simply to the inability of the flight crew to clearly see and set the controls for a return to Kuala Lumpur.

Vincent guesses that control could have been regained and the aircraft sent back to a lower altitude of around 23,000 ft – which is a diversion altitude set by manufacturers of large transport aircraft to prevent a fire taking further hold and which both allows better survivability for those on board and vents the avionics bays.

The final report of a UPS B747 crash in Dubai in 2010, details how that crew similarly attempted to depressurise the freighter aircraft to slow down the fire 30 seconds after the loss of aircraft systems and flight controls. In that accident, the time interval between fire detection and the onset of aircraft system failures was around two and a half minutes.

The last verbal communication from Flight 370 was issued at 1.19 am as the aircraft left Malaysian airspace. It then disappeared from air traffic controllers’ screens at 1.21 am whilst flying over the South China Sea.

Vincent guesses that the crew did manage to stabilise the aircraft and set it on a new course before once again succumbing to either a loss of oxygen or the remaining toxic fumes.

“The airplane then continues flying until no fuel remains and crashes – most likely into the ocean as there has been no report of any Emergency Locater Transmitter (ELT) signal which can be received by satellite if the crash were on land,” says Vincent.

Vincent insists other scenarios involving hijacking and sabotage are improbable. “For instance, there is no indication that either of the pilots was criminally involved in the disappearance of this airplane. Neither has Malaysia released any data indicating anything amiss in the security clearance of the passengers for this flight. The one question raised about the two passengers travelling on stolen passports has been cleared indicating that they were planning on illegally claiming refugee status in another country, probably Germany.”

“I have yet to see anything released about the nature and content of the cargo carried in the cargo hold of Flight 370. Hazardous cargo can be legally carried on passenger aircraft. However, the amount and type of such hazardous materials are strictly controlled,” says Vincent.

While all hazardous materials must be properly contained and labelled – and declared to the airline transporting it, Vincent notes that hazardous materials have been – knowingly and unknowingly – labelled improperly for carriage on passenger aircraft in addition to having been carried on board unlawfully by passengers.

Though entirely within the law, a 2013 report by the UK’s Royal Aeronautical Society warned that passengers flying on a typical single aisle jet could be bringing more than 500 potentially lethal batteries on board – both in the cabin and the hold – to power personal gadgets.

The report documents how a fire occurred in April 2012 on a flight from Toronto to Minneapolis at 28,000ft when the battery from a passenger’s air purifier device combusted. A cabin crew member wet paper towels to put out the fire before submerging the smouldering battery in a cup of water. On the flight deck, meanwhile, the captain, smelling a strong burning electrical odour, declared an emergency and diverted to Michigan.

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