On June 11, 1934 he assumed command at NAS Lakehurst, and was promoted to commander on 1 February 1935. Rosendahl served as an official observer on the German airship , on transatlantic flights between Frankfurt and Rio de Janeiro in August–September 1936. He was in command at Lakehurst on the night of May 6, 1937 and witnessed the destruction of the "Hindenburg", leading fire fighting and rescue efforts. He later testified at the Department of Commerce Inquiry into the accident and stated: