Historically , many accidents and catastrophes have resulted from microsleep episodes in these circumstances . For example , a microsleep episode is claimed to have been one factor contributing to the Waterfall train disaster in 2003 ; the driver had a heart attack and the guard who should have reacted to the train 's increasing speed is said by his defender to have microslept , thus causing him to be held unaccountable . On May 31 , 2009 , an Air France plane ( Air France Flight 447 ) carrying 228 people from Brazil to France crashed into the Atlantic Ocean , killing everyone on board . The pilot of the plane reported " I did n't sleep enough last night . One hour – it 's not enough , " handing over control to the two co-pilots who did not respond appropriately when the plane was in distress . Perhaps the most notable example was the Chernobyl nuclear reactor accident in Ukraine in April , 1986 . The reactor began to overheat at about 1:30 am because critical cooling valves were shut off . The shiftworkers , sleep-deprived and likely experiencing microsleeps with consequent reduced decision-making ability , mistakenly disabled the cooling system , causing the reactor to overheat . As a result , there was a destructive explosion , resulting in numerous radiation-related injuries and casualties
Air France Flight 447
Air France Flight 447
Microsleep