In the 1954 Operation Castle nuclear test series at Bikini Atoll, a crucial experiment by Lew Allen proved that nuclear explosives could be used for propulsion
Two graphite-covered steel spheres were suspended near the test article for the Castle Bravo shot. After the explosion, they were found intact some distance away, proving that engineered structures could survive a nuclear fireball
I’m fairly well versed in the history of the nuclear test program, but I am unfamiliar with any propulsion test during the Castle series.
Could you kindly provide more info? Thanks.