Alexei Leonov

"On 18 March 1965, a 30-year-old Soviet Air Force pilot named Alexei Leonov opened the hatch of an inflatable airlock on Voskhod 2 and became the first human being to float free in space."https://spacedaily.com/sd-in-1965-soviet-cosmonaut-alexei-leonov-stepped-outside-voskhod-2-for-the-first-spacewalk-in-history-and-his-suit-ballooned-so-badly-in-vacuum-that-he-had-to-bleed-oxygen-through-a-valve-to-fit-ba/