The British Aircraft Corporation TSR-2 was a cancelled supersonic strike and reconnaissance aircraft designed by the British Aircraft Corporation (BAC). It was under development throughout the late 1950s and early 1960s for the Royal Air Force (RAF); the TSR-2 designation came from "Tactical Strike and Reconnaissance, Mach 2".
The TSR-2 arose from the issuing of General Operational Requirement 339 (GOR.339) in November 1956, which sought a successor to the English Electric Canberra that would perform both conventional and tactical nuclear weapons delivery, be able to penetrate well-defended frontline areas at low altitudes and very high speeds, and attack high-value targets in rear areas. Another intended combat role was to provide high-altitude, high-speed stand-off, side-looking radar and photographic imagery and signals intelligence, aerial reconnaissance. On 1 January 1959, the project received its official go-ahead; early work was undertaken by Vickers-Armstrong in cooperation with English Electric, before Britain's aircraft industry underwent consolidation to create BAC. However, as some contributing manufacturers were employed directly by the Ministry rather than through BAC, this led to communication difficulties and cost overruns. On 27 September 1964, test pilot Roland Beamont performed the type's maiden flight.
Only one example flew and test flights and weight increases during design indicated that the aircraft would be unable to meet its original stringent design specifications. The design specifications were reduced as the result. The decision to cancel the TSR-2 programme came about out of ever-rising costs and inter-service rivalry over Britain's future defence needs. It was decided to order an adapted version of the General Dynamics F-111 instead, but that decision was also later rescinded as costs and development times of that aircraft increased as well.Dorell, David, ed. "Short Cut to Suicide." Air Pictorial, Volume 27, no. 2, February 1965, pp. Cover, 35–36. Operationally, the roles intended for the TSR-2 were taken up by other aircraft, such as the Blackburn Buccaneer and McDonnell Douglas F-4 Phantom II, both of which had been considered and rejected early in the TSR-2 procurement process. Eventually, the smaller swing-wing Panavia Tornado was developed by a European consortium and introduced during the 1980s to fulfil broadly similar requirements to the TSR-2.
Background
Previous designs
The introduction of the first jet engines in the late-World War II period led to calls for new jet-powered versions of existing aircraft. Among these was the design of a replacement for the de Havilland Mosquito, at that time among the world's leading medium bombers. The Mosquito had been designed with reduced weight to improve its speed. This led to the removal of all defensive armament, improving performance to the point where it was unnecessary. This approach was extremely successful, and a jet-powered version would be even more difficult to intercept.
This led to Air Ministry specification E.3/45. The winning design, the English Electric Canberra, also dispensed with defensive armament, producing a design with the speed and altitude that allowed it to fly past most defences. The design's large wings gave it the lift needed to operate at very high altitudes, placing it above the range where jet fighters could intercept it. The Canberra could fly over its enemy with relative impunity, making it suited to aerial reconnaissance missions. The design was so successful that it was licensed for production in the United States, one of very few such cases. The Martin RB-57D and RB-57F American-built reconnaissance subtypes further extended the wings up to a span for extremely high altitude capabilities.
Canberra replacement It was realised that the Canberra's advantages would be eroded by improvements in enemy interceptor aircraft. As early as 22 February 1952, Air Vice Marshal Geoffrey Tuttle wrote that "Frankly, I do not believe that we will get much operational value out of the Canberra from 1955 onwards... the aircraft is already out of date and I doubt its chances of survival in daylight against the present MiG-15 opposition." As the Canberra's performance appeared to be at its limit, this led to a March 1952 draft requirement for a new light bomber to replace it, but this never went anywhere.
A second round of development began after a January 1953 memo noted that the "thin wing" version of the Gloster Javelin could be modified to be a light bomber. The Javelin had an advanced navigation system that would be useful in this role. This led to operational requirement OR.328, but this was rejected as the range was too small when it was flown at low altitude. English Electric then began work on a Royal Navy requirement for a low-altitude strike aircraft, which was won by Blackburn with the Buccaneer. With minor changes, English Electric submitted their Navy entry to the RAF for the same role as OR.328. This was reviewed in October 1955, along with the winning Blackburn design, and rejected. Matthew Slattery stated that further redesign was needed to make them useful by the time they might enter service around 1960, concluding "it seems quite wrong to introduce in 1960 a subsonic aircraft that stands no hope of being supersonic."
Meanwhile, the Canberra was still proving useful in spite of new Soviet interceptors, but the widespread introduction of the first of the Soviet Union's surface-to-air missiles (SAMs) in the late 1950s was a major threat. SAMs had speed and altitude performance much greater than any contemporary aircraft. The Canberra, and other high-altitude aircraft like the British V bombers or US Boeing B-52 Stratofortress, were extremely vulnerable to these weapons. The first aircraft to fall victim to the Soviet S-75 Dvina (NATO name "SA-2 Guideline") SAM was a Taiwanese RB-57 shot down in 1959.
The solution was to fly lower: since radar operates in line-of-sight, the curvature of the Earth renders low-flying aircraft invisible beyond a certain range, the radar horizon.Spick 1986, pp. 6–8. In practice, trees, hills, valleys and any other obstructions reduce this range even more, making a ground-based interception of low-flying aircraft extremely difficult. The Canberra was designed for medium- to high-altitude flight and was not suitable for continuous terrain-hugging flight. Low-level strike aircraft, or "interdictors", grew into a new class during the late 1950s. They generally had a high wing loading to reduce the effects of turbulence and cross-wind, some form of terrain-following radar to allow very low flight at high speeds, and large fuel loads to offset the higher fuel use at low altitudes.
GOR.339
Aware of the changing operational environment, the Ministry of Supply started work with English Electric in 1955, attempting to define a new light bomber to replace the Canberra.Flight, 9 October 1969, p. 570. These early studies eventually settled on an aircraft with a ferry range, Mach 1.5 speed "at altitude" and low-level range. A crew of two was required, one being the operator of the advanced navigational and attack equipment. The bombload was to be four bombs.
The requirements were made official in November 1956 with General Operational Requirement 339 (GOR.339), which was issued to various aircraft manufacturers in March 1957. This requirement was ambitious for the technology of the day, requiring a supersonic all-weather aircraft that could deliver nuclear weapons over a long range, operate at high level at Mach 2+ or low level at Mach 1.2, with STOL or possible VTOL performance. The latter requirement was a side-effect of common battle plans from the 1950s, which suggested that nuclear strikes in the opening stages of war would damage most runways and airfields, meaning that aircraft would need to take off from "rough fields" such as disused Second World War airfields, or even flat and open areas of land.
Specifically, the requirement included: Delivery of tactical nuclear weapons at low level in all weathers, by day and night Photo-reconnaissance at medium level (day) and low level (day and night) Electronic reconnaissance in all weather Delivery of tactical nuclear weapons day and night at medium altitudes using blind bombing if necessary Delivery of conventional bombs and rockets
Low level was stated to be under with an expected attack speed at sea level of Mach 0.95. The operational range was to be operating off runways of no more than . The TSR-2 was to be able to operate at above the ground at Mach 1.1; its range would allow it to operate strategically as well as tactically.
Political changes
As this specification was being studied by various manufacturers, the first of the political storms that were to dog the project reared its head, when Defence Minister Duncan Sandys stated in the 1957 Defence White Paper that the era of manned combat was at an end and ballistic missiles were the weapons of the future. This viewpoint was vigorously debated by the aviation industry and within the Ministry of Defence for years. Senior RAF officers argued against the White Paper's premise, stating the importance of mobility, and that the TSR-2 could not only replace the Canberra, but potentially the entire V bomber force.
In addition to the argument over the need for manned aircraft, additional political machinations had the effect of complicating the project. In September 1957, the Ministry of Supply informed the heads of the aviation companies that the only acceptable proposals would be those issued from teams consisting of more than one company. There was a large number of competing aircraft manufacturing companies in the UK, while orders were decreasing; thus the government intended to foster cooperation between certain companies and encourage mergers.
Another political matter that did not help was the mutual distrust between the various services. At the time that GOR.339 was being defined, the Royal Navy was proceeding with the Buccaneer. The savings associated with both forces using a common aircraft would be considerable, and Blackburn offered the RAF a version of the NA.39 — B.103A — to fit some of the GOR.339 requirements. The Chief of the Defence Staff and former First Sea Lord, Lord Mountbatten, was a loyal proponent of the Buccaneer, later claiming that five of the type could be purchased for the same price as one TSR-2. The RAF rebuffed the proposal, stating that it was unsuitable due to poor takeoff performance and the avionics not being capable of the desired role. As one RAF official put it, "If we show the slightest interest in NA.39 we might not get the GOR.339 aircraft.""The BAC TSR.2." faqs.org. Retrieved: 4 February 2010.
Another political opponent of the TSR-2 project was Sir Solly Zuckerman, at the time the Chief Scientific Advisor to the Ministry of Defence. Zuckerman had a low opinion of British technological achievements and was in favour of procuring military hardware from the United States.
Submissions
English Electric and Hawker Aircraft had already received some signals from the Air Ministry that a formal process would be starting, but all of the major manufacturers were able to quickly put together submissions: Blackburn entered B.103A, which was essentially a B.103/NA.39 (Buccaneer) with its naval equipment removed and new fuel tanks installed. De Havilland entered an upgraded version of the de Havilland Sea Vixen, the "DH.110 Tactical Bomber', modified to remove naval systems and increase fuel through a fuselage extension. It also added an upgraded version of the Rolls-Royce Avon engines, blown flaps, and an attachment point for an under-fuselage rocket engine JATO unit, all to improve takeoff performance. Vickers-Armstrongs/Supermarine offered Type 565, a similar conversion of the Supermarine Scimitar.