Could Britain Have Been First to Fly a Supersonic Aeroplane? During the summer of 1942 the British government decided to embark upon an ambitious new project. The Air Ministry and the Ministry of Aviation approached Miles Aircraft with a secret contract for a jet engine-powered research aircraft designed to fly at a speed greater than the speed of sound.
Air Ministry specifications called for an aeroplane capable of flying more than twice as fast as any existing aircraft. At the time, no aeroplane had ever exceeded the sound barrier though there were unconfirmed reports of Spitfires and Mustangs going through the sound barrier in steep dives1.
Dubbed the Miles M.52, the secret aircraft would be designed for a speed of 1,000mph, with the ability to climb to 36,000 feet in 1.5 minutes.
The boundaries of design and technology were being pushed forward all the time. The wings of the M.52 were very thin and designed to remain within the V-shaped shockwave generated by the aircraft's nose at supersonic speeds. In the forward section of the fuselage, the pilot sat in a pressurised pod, which could be separated from the aircraft in the event of an emergency using explosive bolts. However, the pilot did not have the advantage of sitting in a modern ejector seat, meaning that he would then have to attempt to climb out of the tumbling capsule at close to supersonic speeds - a near suicidal manoeuvre.
The contract for the development of an engine for the M.52 went to the Whittle Company, headed by Frank Whittle - the inventor of the jet engine. The resulting engine was given the designation W2/700 and was fitted with an afterburner2.
In 1943, Whittle's company was taken over by Rolls Royce, which used the W2/700 as the basis for a whole series of jet engines, including the Rolls Royce Derwent, which went on to be fitted to the Royal Air Force's first operational jet fighter - The Gloucester Meteor3. Further power was to have been obtained by fitting a specially designed ducted fan to increase the airflow through the engine system. This is what modern turbofan engines currently employ.
The American Connection
In 1946 a team of American engineers from Bell Aviation, who were also working on a supersonic aircraft project, visited the top-secret research facility of the Miles Aircraft company. The British government instructed the company to co-operate fully with the Americans, in return for data on the United States' own supersonic programme4.
It is known that the Bell company had been having serious problems with control of their aircraft as it approached the sound barrier. The Miles team had overcome this snag with a completely new idea - the all-flying tailplane.
Basically, up until then, the horizontal tailplanes of all aircraft had been fitted with small flaps on their trailing edges to aid with vertical stability. The all-flying tailplane did away with these flaps, which were just not large enough to counteract the enormous forces encountered at supersonic speeds, and designed an aircraft where the entire horizontal tailplane pivoted, thus giving a much greater movable surface area with which to control the vertical pitch of the aircraft. This was a significant breakthrough, in fact Chuck Yeager5 is on record as saying that the single most significant contribution to the final success of the Bell XS-1 was the all-flying tailplane.
Within a few weeks of the American's visit, the Air Ministry Director of Scientific Research, Sir Ben Lockspeiser, cancelled the British supersonic project, saying:
...in view of the unknown hazards near the speed of sound ... [it is] considered unwise to proceed with the full-scale experiments.
Despite 90% of the design work being completed and half of the construction finished, the project fell, apparently due to a Treasury savings measure.
The Air Ministry ordered Miles to break up all jigs6 and to send all their design data to Bell Aviation. As it seems likely that the M.52 would have been flying by the summer of 1946, and since it would most likely have achieved its specified performance, it is hard not to believe the British government was pressured by the Americans to cancel the M.52 project.
This allowed the US become the first 'through the barrier', in October 1947, using the rocket-powered M.52 lookalike, the Bell XS-1. As an added bonus, the Americans' first jet engine, the General Electric Type 1, drew heavily on the designs of the British jet.
Following the cancellation of the M.52, the government instituted a new programme involving 'no danger to test pilots and economy in purpose'. This was another way of saying that it was planned to use expendable, pilotless, rocket-propelled missiles. The Royal Aircraft Establishment was responsible for the development of a suitable rocket motor and in charge of aircraft design was Barnes Wallis7 from Vickers Armstrong.
The rockets were exact 3:10 scale replicas of the M.52 and the first launch took place on 8 October, 1947.
A Mosquito light bomber took off from an RAF airfield in Cornwall with a rocket-powered model strapped to its belly. Sadly, the motor exploded shortly after launch. Following this, and the success of the XS-1 the Daily Express took up the cause for the restoration of the M.52 programme, but to no avail.
In October, 1948, a second rocket powered model was launched. This was successful and achieved a speed of Mach 1.5.
One interesting titbit of information, purportedly from a member of the development team, was that at the end of the flight, it was planned that the aircraft would be given instructions that would send it into an 'impossible manoeuvre', a 15G turn, thus destroying the aircraft and letting the pieces fall back into the sea. However, what actually happened was that on the successful completion of the test, the 'self-destruct' command was transmitted, but, instead of the aircraft being destroyed by the manoeuvre, it was suddenly discovered that the airframe was so well designed that it survived what was thought to be impossible, and it was last observed on radar heading serenely out over the Atlantic Ocean.
The final irony came when even these rocket trials were suspended, the reason being given as, 'the high cost for little return'. The consolation from this investment was the information that a small scale model of the Miles M.52 had successfully broken the sound barrier. Sadly, the United Kingdom had already lost the chance of being the first nation to break the sound barrier.