 He did this because he was aware that during some crashes a full bladder could prove fatal.Paul Brickhill (in "The Dam Busters") referred to the two test pilots Joseph Summers and Jeffrey Quill, as "Mutt" and "Jeff", alluding to the characters in the pioneering American comic strip created by Harry Conway "Bud" Fisher.Summers was granted a short-service commission in the RAF at the age of 21, and learned to fly on Avro 504s and Sopwith Snipes at No.