Selfridge was stationed at the Presidio during the great San Francisco earthquake of April 18, 1906. His unit participated in search and rescue as well as cleanup operations. In 1907, he was assigned to the Aeronautical Division, U.S. Signal Corps at Fort Myer, Virginia, where he was later instructed in flying a dirigible. He was also the United States government representative to the Aerial Experiment Association, which was chaired by Alexander Graham Bell, and he became its first secretary.