Merely for the purpose of studying the effects of a nuclear blast on civilians and ground forces, an explosive nuclear experiment was conducted at 09:53 hours on September 14, 1954. Under the direction of Marshall Zhukov, a Soviet bomber, flying at an altitude of 42,000 feet (13 kilometers), dropped a 40-kiloton nuclear bomb.
https://europeansworldwide.wordpress.com/2020/07/20/the-censored-nuclear-catastrophe
