potentially dangerous nuclear power plants. For business reasons, General Electric and Westinghouse decided that the types sold would be versions based on the reactors used in nuclear submarines, but sold with dubious claims made about their cost effectiveness and safety. However, in 1964, at the Atomic Energy Commission it was found that while small reactors were safe, the bigger core sizes as used in power plants were potentially susceptible to nuclear meltdown—an accident where the reactor core could melt through the bottom of the reactor containment vessel. A study showed this could potentially happen, and if it did, it could damage the reactor. These concerns were largely kept from the public. The episode goes into some detail over attempts to find solutions to the meltdown issue. In the Soviet Union, reactors were considered too expensive, until Brezhnev came to power. Under his leadership, Anatoly Petrovich Alexandrov designed cheap reactors that were produced at high speed, with very few safety features, sometimes not even containment vessels. This was publicly criticized by experts, but the experts were sidelined. In Britain, by 1974, delays to its native advanced gas cooled reactor power plant caused Britain to adopt the American PWR design of reactors. However, in America it was being discovered that safety systems that had to work to avoid meltdown could not be guaranteed to work reliably in the complex circumstances in a nuclear reactor. Tests run on the emergency core-cooling systems to deal with pipe breaks, performed on the Atomic Energy Commission's test models in Idaho in 1971, repeatedly failed; often the water was forced out of the core under pressure. It was discovered that the theoretical calculations had no correspondence with reality. Nevertheless, they had not necessarily proved that they wouldn't work on a real reactor, so they decided to carry on with mandated safety systems, that the best evidence suggested, may well not function in the event of an accident. Engineers and scientists and regulators that tried to publicise the potential issues found that their concerns were not published, and these issues remained largely unknown to the public, and nuclear power had a high degree of confidence with the public. Then came the disasters of Three Mile Island in 1979 and Chernobyl in 1986, which changed public views on the safety of this new technology. It revealed that the industry had been hiding the problems and unpredictable nature of these