GB 'Super Sportster', the famous 'flying cask' of brothers Granwill, the winner of Thompson's prize race in 1931 and 1932, was built by the firm Aircraft GB in 1931. Everything in aircraft's design was sacrificed to speed. Robert Hall, the plane's chief designer from the US, practically turned it into a flying engine. The aircraft appeared to be very difficult in piloting and caused the death of many well-known pilots.