Question:  David John Shannon was selected to join the newly formed No. 617 Squadron by the most highly decorated serviceman in the country who completed over how many operations at the age of 26?
Sentence (from "Guy Gibson"): Wing Commander Guy Penrose Gibson, {'1': ", '2': ", '3': ", '4': "} (12 August 1918 – 19 September 1944), was the first Commanding Officer of the Royal Air Force's No. 617 Squadron, which he led in the "Dam Busters" raid (Operation Chastise) in 1943, resulting in the destruction of two large dams in the Ruhr area.
Relevant evidence: Yes