The two vital prototypes from which came the fighters that won the Battle of Britain. Above, the K 5054, the prototype Spitfire which was first flown on March 5th, I936, and which soon achieved 349 m.p.h. during tests. Below the first Hurricane which flew on November 6th, I935, and attained 3I5 m.p.h. while on trial at Martlesham Heath.