The Spitfire entered operational service with the Royal Air Force 80 years ago this month. In this feature we take a look at the legendary aircraft in its earliest form.
The Spitfire is a genuine design classic. It looks beautiful with its sleek lines and distinctive semi-elliptical wings, and it was superb in the role for which it was intended - as a home defence fighter - and in other roles too.
It also sounds wonderful - the note of the Rolls Royce Merlin engine is incredibly evocative as the aircraft passes overhead. Even the name ‘Spitfire’ seems perfect to us today, certainly more inspiring and appropriate than a name it might have had - ‘The Shrew’!
In the early 1930s, the Royal Air Force was equipped with outmoded biplane fighters that were slow and lightly armed. Bomber technology was developing apace and there was a growing risk that the RAF would be unable to protect Britain from raiders in the event of another major war in Europe.
In an effort to address the evident shortfall in interceptor capability, the Air Ministry issued specification F7/30 to the British aviation industry, calling for a four gun fighter capable of 200mphat 15000ft.
In response, Supermarine’s Chief Designer, Reginald J Mitchell, initially came up with an open cockpit monoplane design ( the Type 224 ) that had an inverted gull wing configuration and a fixed undercarriage. The aircraft was something of an ‘ugly duckling’ and its performance left rather a lot to be desired.
It was not an auspicious start for Supermarine, but Mitchell (who had already been thinking about a more radical design) persevered, drawing inspiration from his fast and sleek racing seaplanes that had won the Schneider Trophy outright for Britain (at speeds around 400 mph).
A new design concept emerged - the Type 300 - which through a process of refinement evolved into an all metal monoplane with thin semi-elliptical wings, an enclosed cockpit and retractable undercarriage, powered by the new V-12 Rolls Royce PV-XII engine (later named the ‘Merlin’).
At the beginning of 1935 an impressed Air Ministry issued specification F10/35, based around Mitchell’s design. The prototype K5054 took to the air for the first time, at Southampton’s Eastleigh Aerodrome, on 5 March 1936, four months after the maiden flight (at Brooklands, Surrey) of another promising British fighter prospect, the Hawker Hurricane.
The refined Type 300 was formally named the ‘Spitfire’ in mid 1936, although the somewhat less glamorous name of ‘the Shrew’ had also been considered during development. Mitchell himself was not at all pleased with the name ‘Spitfire’ apparently.
Mitchell had unfortunately been diagnosed with cancer in 1933 and this recurred in 1936 forcing him to give up work in early 1937. He died, aged just 49, in June that year so sadly didn’t live to see his aircraft achieve legendary status. Mitchell’s story was dramatised in a stirring 1942 film - ‘The First of the Few’ - directed and starring Leslie Howard.
Early flight trials showed the Spitfire was clearly an outstanding design - simple to fly, stable in level flight and (with a top speed around 350 mph) considerably faster than the biplane fighters then in service with the RAF.
But some further enhancements were still needed before the aircraft could enter operational service - the curved windscreen gave a distorted view, the rudder proved to be somewhat oversensitive and the two-blade propeller also needed modification.
There was also an issue encountered in relation to the guns which had a tendency to jam at high altitude due to freezing, a problem that was eventually resolved by ducting warm radiator air to the gun bays.
In May 1938 the first production Spitfire flew, an initial order for 310 aircraft having been placed by the Air Ministry in 1936. No.19 Squadron, based at RAF Duxford, became the first unit to re-equip with the new fighter in August 1938.
The Spitfire was certainly a very different beast from the open-cockpit, fixed undercarriage Gloster Gauntlet biplane that RAF fighter pilots were typically flying previously. Not only did the pilots have to contend with the vastly increased speed and power of the new aircraft, they also needed to remember to lower the undercarriage before landing!
The Spitfire’s long nose did not give a particularly good view forward when the aircraft was on the ground, requiring pilots to weave the aircraft when taxiing.
Also, the compact underwing radiator did not receive a great deal of cooling ‘wash’ from the turning propellor so the engine could not be kept running on the ground for very long without risking overheating.
But in the air the graceful new aircraft handled beautifully and RAF pilots were enamoured with it, recognising that it was a true thoroughbred and was just what was needed in the face of the growing Nazi threat.
The very earliest Mark 1 Spitfires in RAF squadron service were fitted with two bladed propellors and fabric covered ailerons, and the cockpit canopy was straight-sided rather than bulbous. There was no armoured windscreen.
These first aircraft were fitted with a primitive ring and bead gunsight the would soon be replaced by a (far more effective) reflector gunsight. The port underside of the aircraft was painted black, and the starboard underside white to aid identification by Observer Corps personnel on the ground.
The Merlin engine ran on 87 octane fuel, rather than the 100 octane fuel which became the standard early in the Second World War.
The oldest surviving Spitfire, K9942, was part of the first production batch and is today displayed in early Mark 1 configuration at RAF Museum Cosford in Shropshire.
Developing a world-beater was one thing, building it in sufficient quantities proved to be quite another - at least initially.
Spitfire manufacture involved many new techniques and Supermarine, a relatively small company, also had capacity issues. Supermarine’s parent company, Vickers, were also stretched so a lot of the production work had to be sub-contracted.
However this did not go smoothly and at one stage in 1938 the Air Ministry, frustrated by the lack of progress, actually considered halting Spitfire production in favour of the Bristol Beaufighter - an intervention that potentially could have altered the outcome of the Battle of Britain.
Even those masters of mass production Morris Motors struggled to meet expectations - their giant new Spitfire factory at Castle Bromwich took longer to complete than expected and production was initially hampered by industrial disputes, skills shortages and the management’s reluctance to use Supermarine’s tooling and drawings.
No surprise then that by the outbreak of the Second World War, the RAF only had 10 operational Spitfire squadrons. Fortunately for the RAF, production of the more straightforward Hawker Hurricane had faired better, and there were 16 squadrons available.
But unlike the Hurricane, the Spitfire had considerable potential for further development which meant that Mitchell’s masterpiece was destined to remain at the cutting edge of fighter design until the arrival of the first jet aircraft late in the war.