说明:
Made in 1953, "Operation Doorstep" shows the Upshot-Knothole Annie nuclear weapons test conducted by the United States as part of Operation Upshot-Knothole. This took place at the Nevada Test Site on 17 March 1953, and was nationally televised. The broadcast as well as this film suggests that it is possible to survive an a-bomb blast, as long as you have a good fallout shelter or other protection. Unfortunately, just a few years after this film was made, larger and larger yield nukes and the H-bomb made the proposition of survival quite unlikely. Operation Doorstep was a civil defense study conducted by the Federal Civil Defense Administration in conjunction with the Annie tests. It studied the effect of the nuclear blast on two wooden frame houses, fifty automobiles and eight bomb shelters designed for residential use. The film shows blast and thermal effects on mannequins, automobiles, and wooden frame houses, simple basement shelters and complex underground, reinforced-concrete shelters. Soldiers involved in the Desert Rock V exercise are seen in their foxholes with Civil Defense leaders. Observers on "News Nob" are shown illuminated by the explosion. Stop-motion views are shown of a house blown apart by the blast wave. The administration concluded that if windows were left open to prevent the car collapsing on its occupants a car would be "relatively safe" from a small nuclear bomb if at least ten blocks away from the hypocenter. The homes in the study were constructed in such a way as to minimize the thermal effects of Annie, with an eye towards determining if, in the absence of fire, the basement of the closer home — 3,500 feet (1,100 m) from the hypocenter — might shelter its occupants, while the second — at 7,500 feet (2,300 m) — could remain standing. Both homes performed as expected under the conditions of their construction. We encourage viewers to add comments and, especially, to provide additional information about our videos by adding a comment! See something interesting? Tell people what it is and what they can see by writing something for example like: "01:00:12:00 -- President Roosevelt is seen meeting with Winston Churchill at the Quebec Conference." This film is part of the Periscope Film LLC archive, one of the largest historic military, transportation, and aviation stock footage collections in the USA. Entirely film backed, this material is available for licensing in 24p HD and 2k. For more information visit https://periscopefilm.com/
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