Spitfire! ....and this one in the photo looks like it is the very first one that was flown.
K5054.........."The unpainted Supermarine Type F37/34 did not fly until March 1936. Although some reports say that the prototype first flew on the 6th March, it was in fact on the 5th of the month that the aircraft, built at Woolston and assembled at Eastleigh Airport, took to the air under the watchful eye of the designer, Supermarine staff, and an interested group of civil flying school pupils. The pilot, Mutt Summers, flew the aircraft, still unnamed but now registered as K5054, around the airfield checking the flaps and flying characteristics of the plane. The undercarriage was not retracted during this maiden flight. After only a few minutes K5054 landed and Summers announced to the anxious spectators that all was fine and that he did not want anything touched.
After this historic first flight, Mutt Summers made three or four more test flights. The aircraft was then returned to the workshops to be repainted high-gloss blue/grey. On the 27th March 1936 test pilot Jeffrey Quill flew K5054 to set accurate performance figures of 335 mph at 17,000 feet. This proved disappointing compared to Mitchell's estimated 350 mph. Supermarine had already been working on a new propeller with modified tips. This was fitted later on 27th March and Quill took the aircraft up again this time achieving 348 mph. This satisfied Mitchell and so the aircraft went to Martlesham Heath (near Ipswich) for RAF trials on the 26th May 1936, flown by Mutt Summers.
Only seven days later on 3rd June 1936, before any test reports had reached the Air Ministry, the Royal Air Force placed a production order for 310 Supermarine Spitfires.....
http://www.spitfiresociety.demon.co.uk/spitdev.htm
,but a small addition.