 This was followed by the military troop transport the Vickers Valetta, which Summers flew on 30 June 1947 at Brooklands.The prototype of the turboprop civil transport Vickers Viscount was flown from Wisley Airfield by Summers and Jock Bryce for 10 minutes on 16 July 1948.The very last prototype to have Summers at the controls on its maiden flight was the Vickers Valiant, once again with Jock Bryce as co-pilot, flown from Wisley Airfield on 18 May 1951.