 Four years later, he was a member of the U.S. field hockey team at the 1936 Summer Olympics in Berlin, during which he met Adolf Hitler.Turnbull enlisted in the Maryland National Guard as an aviation cadet and was commissioned as a second lieutenant on June 24, 1940.He was mobilized along with the rest of the Maryland National Guard in February 1941, just prior to the U.S. entry into World War II.