Fukushima Daiichi nuclear disaster (Unit 3 Reactor) 13 March an official of the Japan Nuclear and Industrial Safety Agency (NISA) told at a news conference that the emergency cooling system of Unit 3 had failed, spurring an urgent search for a means to supply cooling water to the reactor vessel to prevent a meltdown of its reactor core. At 05:38 there was no means of adding coolant to the reactor, owing to loss of power. Work to restore power and to vent excessive pressure continued. At one point, the top three meters of the uranium/mixed oxide (MOX) fuel rods were not covered by coolant. At 07:30 JST,
Chain of events (accident analysis) a chain of events and errors can be identified leading up to the crash. Pilot error, communications problems, fog, and airfield congestion (due to a bomb threat and explosion at another airport) all contributed to this catastrophe. Chain of events (accident analysis) In accident analysis, a chain of events (or error chain) consists of the contributing factors leading to an undesired outcome. In aviation accidents and incidents, these contributing actions typically stem from human factor-related mistakes and pilot error, rather than mechanical failure. A study conducted by Boeing found that 55% of airline accidents between 1959 and 2005 were caused