Thomas was assigned to Jagdstaffel 9 in December 1917. He shot down his first enemy observation balloon on 3 January 1918. He carried on his career as a balloon buster for Jasta 9 through 16 March 1918, when he downed numbers seven and eight. He then transferred to Jagdstaffel 22, and shot down a ninth balloon on 21 March, and a Sopwith on the 22nd. On 23 March, he attacked another French balloon and was shot down by Jean Chaput, Marcel Haegelen, and Auguste Lahoulle. Thomas was taken prisoner of war.^[1]

• Above the Lines: The Aces and Fighter Units of the German Air Service, Naval Air Service and Flanders Marine Corps 1914 - 1918 Norman L. R. Franks, et al. Grub Street, 1993. ISBN 0-948817-73-9, ISBN 978-0-948817-73-1.