You were on your own.
Excerpts below from the Nuclear Files Org. Update on 4/27/2021: inexplicably, this link is broken. I can access other decades, but for some reason I cannot pull the file on nuclear accidents in the 1950s from the archived nuclearfiles.org 13 February 1950U.S.A., Pacific Ocean- A B-36 which developed serious mechanical difficulties on a simulated combat […]
…not until 1949 that decrypted cables from the United States Army Signal Intelligence Service (SIS)’s “Venona” project revealed Fuchs was a Soviet spy.