Miles M.52

The Miles M.52 was a planned British supersonic - research aircraft , which was developed between 1942 and 1945 in the greatest secrecy. The British Air Ministry canceled the project for reasons that are still controversial today, and sent the results acquired by then to the American Bell Aircraft Corporation . Two years later, the Bell X-1 made the world's first manned supersonic flight.

specification

The British company Miles Aircraft Ltd had extensive experience in the development of aircraft, but remained relatively unknown. In 1942 the British Air Ministry turned to a top-secret Treaty Specification E.24 / 43 on Miles, a research aircraft with jet engine build, which should be capable of supersonic speed to reach. The aircraft was supposed to reach over 1,600 km / h in level flight, more than double the speed record of the time, and an altitude of 11,000 meters in just 1.5 minutes.

Technical characteristics

A large number of technical innovations were to be incorporated into the M.52. Many of them point to a detailed knowledge of the aerodynamics in the supersonic range, which became publicly known only years later due to the war. In particular, very thin wings with low drag were provided, and the wing tips were shortened to avoid the effects of the conical shock wave emanating from the nose of the aircraft. Another key element was a fully movable tail unit ( pendulum rudder ), which was necessary for effective control in the supersonic range and which differed from the traditional tail unit design with rudder surfaces suspended on fins. As little information was available about the warming of flying objects in the supersonic range, the use of stainless steel was provided instead of duralumin .

Frank Whittle's latest engine development, the Power Jets W.2 / 700, was to be used as the propulsion system. However, that alone was not able to develop enough thrust for a supersonic flight. Therefore, an afterburner should also be used, then called the reheat jetpipe by the British . In order to transport more air to the afterburner than could have flowed through the relatively small engine, an additional fan was installed in front of the engine, which supplied additional air through lines around the engine. Finally, another important element was a cone on the air inlet to brake the incoming air to the subsonic speed required by the engine. This cone was also used in many post-war jets, such as B. the English Electric Lightning and the MiG-21 used.

The pilot was supposed to sit in a small cockpit within this cone, which in an emergency could be completely blown off the aircraft as an escape capsule. He should wait a while until the cone was slowed down enough to then parachute out. However, there were serious concerns about the exit from this capsule, as it could not stabilize itself at supersonic speeds, which could have caused the capsule to tumble or even break apart.

Prototypes

By 1944, construction was about 90 percent complete, and Miles was due to begin building three prototypes. In the same year, the Air Ministry signed an agreement with the USA to exchange information and data on the supersonic flight. The Bell Aircraft Company received all of the drawings and research, but the US broke the agreement and did not hand over any data. Unbeknownst to Miles, Bell had already begun designing a supersonic rocket-propelled aircraft, but the controls were still a problem there. A variable angle of attack tail appeared to be the most promising solution, and Miles' data seemed to confirm that assumption. Chuck Yeager was later able to confirm this assumption experimentally, whereupon all subsequently built supersonic aircraft had a pendulum rudder or delta wing .

Project termination

At the end of the Second World War, the first of the three prototypes of the M.52 was just over 50% complete. The flight attempts should begin only a few months later. However, the Labor government decided to cut the budget dramatically in 1946, and the head of scientific research, Sir Ben Lockspeiser , canceled the project. The decision was based on the fact that many of the captured German high-speed aircraft had swept wings , and the government believed that attempting to break the sound barrier with an aircraft with unearthed trapezoidal wings would be suicide.

Further developments

The British government launched a new unmanned missile program instead. The design was left to Barnes Wallis by Vickers-Armstrong , while the engine was taken over by the RAE . The result was basically a 1: 3 scale model of the M.52.

The first launch was on October 8, 1947, but the rocket exploded shortly after launch. A few days later, the X-1 broke the sound barrier in the USA. As a result, the Labor government's research policy was heavily criticized and the Daily Express called for the restart of the M.52 program, but to no avail. In October 1948 a second rocket was launched and reached a speed of Mach 1.5 (1800 km / h). But the rocket did not respond to the radio commands with which it was supposed to be steered into the sea in a controlled manner at the end of the test. The only thing that could be watched on the radar screen was how it was heading towards the Atlantic. Thereupon all further work was stopped.

Museum model

The Wind tunnel model of the Miles M.52 is on display at the Museum of Berkshire Aviation in Woodley , Berkshire west of London . The museum deals with historical Miles and Fairey developments.

Technical specifications

Parameter	Data
crew	1
length	8.5 m
span	8.2 m
Empty mass	3,500 kg
Top speed	1,600 km / h
Engines	1 × Power Jets W.2 / 700 (with afterburner)

Web links

Commons : Miles M.52 - Collection of Pictures, Videos and Audio Files

Museum of Berkshire Aviation Miles and Fairey aircraft