The disaster of Air France Flight 447 (an Airbus A330) and the crash of NASA's Skylab (the first US space station) in 1979 are catastrophes of aviation with a mysterious legacy; experts investigate these historic tragedies to determine what caused these monumental failures of flight.

The nuclear meltdown of Three Mile Island in Pennsylvania (1979) and the deadly hydroelectric turbine tragedy at the Sayano-Shushenskaya Dam in Russia (2009) were power plant disasters of an unprecedented scale; experts examine the aftermath of these fatal catastrophes and explore their lasting consequences.