During one takeoff in April 1916, his engine failed, and he badly injured his knee. The injury was aggravated while on leave in London in May 1916, and Bishop was admitted to the hospital in Bryanston Square. While there he met and befriended socialite Lady St Helier, who was a friend to both Winston Churchill and Secretary for Air Lord Hugh Cecil. After Bishop's father suffered a small stroke, St Helier arranged for Bishop to recuperate in Canada, and as a result he missed the Battle of the Somme.