These Spitfires , which later officially became the Spitfire Mk I PR Type A , had a maximum speed of 390 mph .
Heating equipment was installed on all PR Spitfires to stop the cameras from freezing and the lenses from frosting over at altitude .
These PR Spitfires , which later officially became the Spitfire Mk I PR Type A , had a maximum speed of 390 mph .
Heating equipment was installed on all PR Spitfires to stop the cameras from freezing and the lenses from frosting over at altitude .