Roderic Stanley (Stan) Dallas, DSO, DSC & Bar (30 July 1891 – 1 June 1918) was an Australian fighter ace of World War I. His score of aerial victories is generally regarded as the second-highest by an Australian, after Robert Little, but there is considerable dispute over Dallas's exact total. While his official score is commonly given as 39, claim-by-claim analyses list as few as 32, and other research credits him with over 50, compared to Little's official tally of 47. Like Little, Dallas flew with British units, rather than the Australian Flying Corps. Beyond his personal combat record, Dallas achieved success as a squadron leader, both in the air and on the ground. He was also an influential tactician and test pilot. His service spanned almost the entirety of World War I fighter aviation.