Developed to intercept high flying German reconnaissance aircraft, the Spitfire VI was developed for combat at extreme altitude. The cockpit was pressurised and the wings extended to end in pointed wing-tips, giving greater lift in the thin air. A Merlin 47 engine of 1,415 hp was fitted, driving a four bladed propeller. The Mk VI was produced with the “B” armament of two cannons and four machine guns. The VI had a ceiling of 40,000 feet. 100 Mk VIs were produced.