In June 1918, Summers was posted to No. 209 Squadron RAF, to fly the Sopwith Camel single seat fighter. Between 23 June and 11 August he accounted for eight enemy aircraft; four destroyed (one shared), three driven down out of control (two shared), and one shared capture. However, on 12 August 1918 his aircraft was shot down by Lothar von Richthofen of "Jasta 11", and Summers was taken prisoner. He was held as a POW until after the armistice, finally being repatriated in December 1918.