Nearly six days after the attack that brought down Malaysia Air Flight MH17, the plane's nearly 20-year-old pair of black boxes have been delivered to Malaysian authorities. The handover was the result of an agreement negotiated between Ukrainian separatist leader Alexander Borodai and Malaysian Prime Minister Najib Razak. Now the work begins to free the boxes' flight data recorders and cockpit voice recorders to reveal what they know.
Together, the two data-collecting devices can paint a picture nearly impossible to piece together through other means, which is one reason that Razak, in listing his priorities for the investigation into the downing of Flight 17, ordered them as: "first is the bodies, second is the black box, and third is the crash site."
Flight 17's "loaf" modules, as the black boxes are sometimes described in the aviation business, are designed to withstand a tremendous 3,400 Gs worth of impact. The U.S. National Transportation Safety Board, nonetheless, recommends that flight recorders be gently transferred to investigators "inside a cardboard or wooden box, wrapped in either foam or bubble-wrap or in a container filled with foam peanuts." Still, while the separatists in Donetsk, Ukraine, pulled the pair of units out of what appeared to be a white plastic trash bag, Prime Minister Razak later wrote on Facebook that the boxes "appear to be in good condition."
There are, though, other concerns when it comes to the integrity of such units. There has been a great deal of anger over the pro-Russian separatists' handling of the crash field; Australian Prime Minister Tony Abbott has called it "evidence tampering on an industrial scale." And as invulnerable as they may appear, such black boxes aren't immune to tampering. If the units are correctly hooked up to a power source and allowed to run, the data on them can be rather easily overwritten in the same way that you might record over a VHS tape.
The units aboard MH17 were manufactured by Honeywell, says the New Jersey-based company. (The devices carry markings for both Honeywell and Allied Signal; the latter acquired the former in 1999.) The cockpit voice recorder left the factory in December 1996 and weighs 17 pounds. MH17's flight data recorder left the factory 10 months later, in October 1997, and weighs 19 pounds. The modules are the first-generation of Honeywell's solid-state recorders, which replaced magnetic tapes with more resilient digital storage similar to the electronic memory card you might have in your digital camera.
The flight data recorder captures passively generated data on operating conditions, including the plane's location, speed, altitude and what is called "aircraft attitude," or the plane's orientation to the Earth. Honeywell's FDRs are capable of gathering 25 hours worth of detail on some 2,500 parameters, though the exact makeup of the active list at any time is held by the plane's manufacturer and the operating airline, in this case Boeing and Malaysia Air.
Together that data can be turned by investigators into an animation of the flight's final hours. In the case of Flight MH17, that re-creation might reveal whether and how the plane plotted a path over separatist-controlled land.
Meanwhile, the cockpit voice recorder captures both conversations among cabin staff and between ground crews, as well as ambient noises, what the NTSB calls "engine noise, stall warnings, landing gear extension and retraction, and other clicks and pops."
Those sounds can be extremely useful in many cases, especially in those involving equipment failure, pilot error, or hijacking. As the attack on MH17 was unexpected, those noises might prove less helpful. They could, however, offer insight into the plane's path, as long as the relevant discussions occurred in the flight's final minutes; MH17 was brought down more than three hours after takeoff, and unlike smaller, more compact solid-state models that hold two hours of recording, the cockpit voice recorder on Flight 17 holds just 30 minutes.
The recordings, though, could include audio of people on the plane seeing the missile attack as it was taking place.
Black boxes -- which are actually painted an eye-catching orange -- are manufactured by companies that include L-3, Universal Avionics, and Teledyne. MH17's jet was the same model plane as Malaysia Air Flight 370, which disappeared in March; both were Boeing 777-2000ERs. The latter flight also carried Honeywell-made black boxes. Of course in the case of MH370, though, the black boxes have yet to have been recovered.
Flight data recorders and cockpit voice recorders were once novel technologies. Their creation is generally credited to David Warren, a fuel expert at Australia's Aeronautical Research Laboratories, who was inspired to invent them after the crashes of several Comet jet airliners in the 1950s. But Warren struggled to have his black box adopted by Australian officials.
That acceptance problem has, at least, been solved. A half-century later, black boxes are now a key part of the aviation landscape; national authorities fight surf and rebels to get them after plane catastrophes. In the case of Malaysia Air Flight MH17, the United Kingdom's Air Accidents Investigation Branch is slated to extract and investigate the data once the boxes can be safely delivered aboard the planes of the Belgian Air Force.