The blast force from the missile that slammed into a Malaysian plane over Ukraine, combined with the plane's dramatic deceleration, probably instantly rendered everyone on board unconscious or dead.
That's the best guess of James Vosswinkel, a trauma surgeon who led a definitive study of TWA flight 800 that exploded and crashed off New York's Long Island in 1996, killing all 230 on board. The Malaysian plane carried 298.
Vosswinkel's research found that trauma in a mid-air explosion occurs from three sources: the force of the blast, the massive deceleration when a plane going 800 km/h stops in mid-air, and the impact of the fall. Additionally, the loss of cabin pressure can cause hypoxia within seconds at 10,000 metres, leading to loss of consciousness.
"You have such horrific forces that it's essentially unsurvivable," said Vosswinkel, chief of trauma and surgical critical care at the State University of New York at Stony Brook. "No one was conscious or experienced that fall."
While none of the 230 passengers in the 1996 crash survived, most of their bodies were subsequently recovered. Though the crash occurred offshore, the analysis found none of the passengers had sea water in their lungs, suggesting none were breathing when they entered the water.
The conditions of many of the bodies found in that crash were widely divergent, according to Vosswinkel.
"You had some devastating injuries where the brain and heart were missing," he said. A couple were "totally intact; all they had was a broken neck."
It appears from public reports that flight MH17 had been struck towards its tail, blowing most of the structure away, said Bill Waldock, a professor of safety science at Embry-Riddle Aeronautical University.
The missile "uses a proximity fuse which goes off when it gets close", Waldock said. "The warhead is like a giant shotgun shell sending multiple shards of metal through the plane. It's doubtful it hit the plane, but once you lose the tail you can't fly the plane," he said.
The passengers would certainly have become unconscious, Waldock said. "It's literally an explosive decompression and would have caused a lot of g-force pushing people back in their seats."
While it would have taken the plane minutes to fall from 10,000 metres, hypoxia would have rendered anyone who survived the initial blast unconscious, he said.