It s believed the clear-air turbulence that impacted flight SQ321 would not have been picked up on its state of the art Honeywell IntuVue 3D weather radar - a system used on many 777s.
Pilot and crew error, as well as undiagnosed faults and misfortune, can all play a part in air disasters, which Boeing s 777s have been no stranger to since they came into service in 1995.
From the heroics of pilot Chelsey Sullenberger who savely landed in the Hudson River to the evacuation of hundreds from a burning plane in Dubai, people have survived aviation disasters.