K5054 was the name given to the prototype Supermarine Spitfire as flown by Joseph ‘Mutt’ Summers in March 1936. The flight was such a revelation that on landing Summers said of K5054 “Don’t touch a thing". Work on K5054 started in December 1934. K5054 took off on its maiden flight at 16.30 on March 5th 1936 from Eastleigh Aerodrome in Hampshire. The flight lasted just eight minutes. Summers flew the new aircraft four times before handing testing over to test pilots Jeffrey Quill and George Pickering. K5054 was given a certificate of flight worthiness on April 2nd 1936.
The official cost of K5054 from design board to first flight was officially put at £14,637.
Though the Spitfire gained a reputation as being an excellent aircraft to fly, Summers was not initially impressed with K5054’s rudder, which he felt was too sensitive. However, that aside, the first flight of K5054 led to the famous quote of Summers about engineers changing nothing. Initial flights of K5054 gave it a top speed of 330 mph. In later trial flights, K5054 was fitted with a better-shaped propeller and this pushed its top speed to 348 mph – somewhat faster than the Hawker Hurricane.
The performance of K5054 set the standard for fighter interceptors of the day: after a series of trials the aircraft had a top speed of 349 mph at 16,800 feet. Its rate of climb was 2,400 feet a minute; K5054 took just under 6 minutes to get to 15,000 feet and it had a maximum ceiling of 35,400 feet.
In May 1936, Summers flew K5054 to RAF Martlesham Heath where it was handed over to the AAEE – the Aeroplane and Armament Experimental Establishment – where it underwent service trials for the RAF.
K5054 made its first public appearance at RAF Hendon on June 27th 1936 where it was displayed in the ‘New Types’ section at the aircraft display.
In September 1936, a report on the handling trials was released. It stated that the controls were “quick under all conditions" and that the rudder – modifed since the first flight – was “extremely effective". The report stated that the stability of K5054 in flight was “satisfactory" but that while doing acrobatics in the air K5054 was “very easy and pleasant" to fly. Take-off was “easy" and the undercarriage had “excellent shock absorbing qualities" with ground handling being “extremely good". A summary of K5054’s flying qualities was “simple and easy to fly and has no vices".
In its first few flights, K5054 was unarmed. Now work was done to fit out the aircraft with its armaments and furhter refinements were made. The Air Ministry was so impressed with what K5054 achieved that an order for 310 Spitfires was made on June 3rd 1936. When these rolled off the production line, they were known as Mark I Spitfires. However, further developments to K5054 were used in the production of the Mark II and Mark III.
K5054 became the mould for the Spitfires that fought in the Battle of Britain. However, the aircraft did not always function well. On March 22nd 1937, K5054 had to make a forced landing as a result of engine failure caused by oil pressure problems. K5054 also crashed just one day after World War Two was declared (September 4th 1939) but on this occasion the pilot, Flight Lieutenant White, was killed even though the fuselage was relatively undamaged.