The Hyatt Regency walkway collapse of 1981, where a suspended walkway in a hotel lobby in Kansas City, Missouri, collapsed completely, killing over 100 people on and below the structure. The Space Shuttle Challenger disaster of 1986, in which an O-ring of a rocket booster failed, causing the external fuel tank to break up and making the shuttle veer off course, subjecting it to aerodynamic forces beyond design tolerances; the entire crew and vehicle were lost. The nuclear reactor at the Chernobyl power plant, which exploded in 1986 causing the release of a substantial amount of radioactive materials.