The Luftwaffe test pilot Lothar Sieber (April 7, 1922 - March 1, 1945) may have inadvertently became the first man to break the sound barrier on 1 March 1945. This occurred while he was piloting a Bachem Ba 349 "Natter" for the first manned vertical takeoff of a rocket in history. In 55 seconds, he traveled a total of 14 km (8.7 miles). Unfortunately, there was a crash and he perished violently in this endeavor. Very little of his remains were found in the 15 ft deep crater, but he did receive a funeral with full military honors.[20]
https://en.m.wikipedia.org/wiki/Sound_barrier