Британдық TSR 2 әскери ұшағының прототипі

British reconnaissance strike aircraft prototype

The British Aircraft Corporation TSR 2 is a cancelled Cold War strike and reconnaissance aircraft developed by the British Aircraft Corporation (BAC), for the Royal Air Force (RAF) in the late 1950s and early 1960s. The TSR 2 was designed around both conventional and nuclear weapons delivery: it was to penetrate well defended frontline areas at low altitudes and very high speeds, and then 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. Only one airframe flew and test flights and weight rise during design indicated that the aircraft would be unable to meet its original stringent design specifications. refn|Approximately 14 hours of flight testing were completed on airframe XR219 before the programme was cancelled, with the development phase not fully completed. The TSR 2 was the victim of ever rising costs and inter service squabbling over Britain's future defence needs, which together led to the controversial decision in 1965 to scrap the programme. It was decided to order an adapted version of the General Dynamics F 111 instead, but that decision was later rescinded as costs and development times increased. The replacements included the Blackburn Buccaneer and McDonnell Douglas F 4 Phantom II, both of which had previously been considered and rejected early in the TSR 2 procurement process. Eventually, the smaller swing wing Panavia Tornado was developed and adopted by a European consortium to fulfil broadly similar requirements to the TSR 2.

The introduction of the first jet engines in the late World War II period led to calls for new jet powered versions of practically every aircraft then flying. 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 the express intent of reducing the weight of the aircraft in order to improve its speed as much as possible. This process led to the removal of all defensive armament, improving performance to the point where it was unnecessary anyway. This high speed 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. 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 United States' 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, a US reconnaissance version of the Canberra, 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. 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. Low level strike aircraft, or "interdictors", grew into a new class of their own during the late 1950s. They generally featured high wing loading to reduce the effects of turbulence and cross wind, some form of high performance terrain following radar to allow very low flight at high speeds, and large fuel loads to offset the higher fuel use at low altitudes.

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. 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. This requirement was exceptionally 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 sufficiently flat and open areas of land. Specifically, the requirement included: The TSR 2 was to be able to operate at 200 feet (61 m) above the ground at speeds of Mach 1.1; its range would allow it to operate strategically in addition to tactical scenarios.

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 Buccaneer. 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. 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.

By February, the Air Ministry had reduced the field to three designs, Hawker Siddeley, Vickers and EE. The Ministry was highly impressed with the Vickers submission, which included not only the aircraft design, but a "total systems concept" outlining all the avionics, support facilities and logistics needed to maintain the aircraft in the field. EE, who had recently introduced the Lightning, was the only company with extensive experience with real world supersonic aircraft, which they felt gave it a huge advantage in practical terms. Hawker Siddeley, parent of Hawker, Avro and Gloster, had entered five designs. This led to some confusion and internal dissent within the company. Avro, having lost the Avro 730 project, felt that a new bomber design was naturally theirs to lead. Gloster's design remained based on Javelin, and on 11 December 1957, the Hawker design team stated flatly there was no way it would ever win the contract. A 27 January 1958 meeting between Roy Dodson, Frank Spriggs and J. R. Ewins eventually decided to promote the P.1129 as their primary submission, using the P.1129 as the basis and adding in some features from the 739. Notably, the wing was made thinner and area rule was applied to optimize the design for flight at Mach 1.34. In May, the Air Ministry issued OR.343, a refined version of GOR.339. Hawker submitted their updated "P.1129 Development", while minor variations of the other two designs were offered. Given the similarities between the Vickers and EE, there was some discussion of awarding another series of proposals, one from Vickers and EE and the other from Hawker Siddeley, but it was noted this would delay the final contract by as much as a year. It was later revealed that the decision to drop the Hawker effort had been taken as early as August, and that their later submissions were effectively a "going through the motions" effort. Official opinions of EE's management found it lacking in comparison to Vickers, but the combination of the two was felt by officialdom to be a useful marriage and accordingly the development contract was awarded to Vickers, with English Electric as sub contractor. The ultimate design was essentially the wings and tail sections of the P.17, combined with the longer fuselage of the Type 571, with the design being built in two parts, Vickers the front and EE the rear, and the bolted together at a point just in front of the wing. The existence of GOR.339 was revealed to the public in December 1958 in a statement to the House of Commons. the initials coming from "Tactical Strike and Reconnaissance, Mach 2", the 'Strike' part of the designation specifically referring in RAF terminology to a nuclear weapons role. On 1 January 1959, the project was given an official go ahead; in February, it came under the new designation Operational Requirement 343. OR.343 was more specific and built upon work from the various submissions to GOR.339 specifically stating that the low level operations would be at 200 feet (61 m) or less, and that Mach 2 should be attained at altitude.

Carriage of the existing Red Beard tactical nuclear bomb had been specified at the beginning of the TSR 2 project, but it was quickly realised that Red Beard was unsuited to external carriage at supersonic speeds, had safety and handling limitations, and its 15 kt yield was considered inadequate for the targets assigned. Instead, in 1959, a successor to Red Beard, an "Improved Kiloton Bomb" to a specification known as Operational Requirement 1177 (OR.1177), was specified for the TSR 2. In the tactical strike role, the TSR 2 was expected to attack targets beyond the forward edge of the battlefield assigned to the RAF by NATO, during day or night and in all weathers. These targets comprised missile sites, both hardened and soft, aircraft on airfields, runways, airfield buildings, airfield fuel installations and bomb stores, tank concentrations, ammunition and supply dumps, railways and railway tunnels, and bridges. OR.1177 specified 50, 100, 200 and 300 kt yields, assuming a circular error probable of 1200 feet (366 m) and a damage probability of 0.8, and laydown delivery capability, with burst heights for targets from 0 to 10000 feet (3048 m) above sea level. Other requirements were a weight of up to , a length of up to , and a diameter up to (the same as Red Beard). However, a ministerial ruling on 9 July 1962 decreed that all future tactical nuclear weapons should be limited to a yield of 10 kt. The RAF issued a new version of the OR.1177 specification, accepting the lower yield, while making provision in the design for it to be capable of adaptation later for a higher yield, in the event of the political restriction being lifted. Meanwhile, the RAF explored ways of compensating for the lower yield by including, in the specifications for both the bomb and TSR 2, provision for releasing the smaller weapons in salvos, dropping sticks of four of the revised OR.1177, later named WE.177A, at intervals to prevent the detonation of the first weapon destroying the succeeding ones before they could, in turn, detonate. This led to the requirement that the TSR 2 must be able to carry four WE.177As, two internally and two on external underwing stores pylons—the width of the TSR 2 bomb bay (originally designed to accommodate a single Red Beard weapon) necessitating the reduction in diameter of the WE.177A to , the bomb's width and fin span being constrained by the need to fit two WE.177 bombs side by side in the aircraft's bomb bay. A drawback of carrying WE.177 on external pylons was a limitation due to aerodynamic heating of the bomb's casing. WE.177A was limited to a maximum carriage time of five minutes at Mach 1.15 at low level on TSR 2, otherwise the bomb's temperature would rise above its permitted maximum. This would impose a severe operational restriction on TSR 2, as the aircraft was designed for Mach 1+ cruise at this height. Nuclear stand off missiles were also proposed for the TSR 2 early in development but not proceeded with. These included an air launched development of the Blue Water missile, carried underwing, or semi recessed in the bomb bay, and an air launched ballistic missile, referred to as Grand Slam, with a warhead derived from that intended for the Skybolt missile, and a range of Conventional missiles were catered for instead, with the design originally centring on use of the AGM 12 Bullpup, then moving on to favour the French AS 30 before settling on the new OR.1168 missile (which would become the TV guided AJ 168 Martel). After the cancellation of the TSR 2, the RAF eventually filled the tactical strike requirement using McDonnell F 4 Phantom IIs with US dual key nuclear weapons, but continued their attempts to get the 10 kt limit lifted. Development of WE.177A was delayed by several years due to the Atomic Weapons Research Establishment (AWRE) at Aldermaston being inundated with work on other warhead developments. AWRE workload eased after completion of the Polaris missile warheads and work was able to resume on the WE.177A, deliveries to the RAF beginning in late 1971 for deployment on Buccaneers of RAF Germany, a year after WE.177A deliveries to the Royal Navy. Approval for high yield tactical weapons was eventually gained in 1970 and, by 1975, the RAF had WE.177C, which at almost 200 kt was a weapon very similar to what they had planned for the TSR 2 in 1959. EE had put forward a delta winged design and Vickers, a swept wing on a long fuselage. The EE wing, born of their greater supersonic experience, was judged superior to Vickers, while the Vickers fuselage was preferred. In effect, the aircraft would be built 50/50: Vickers the front half, EE the rear. The design featured a small shoulder mounted delta wing with down turned tips, an all moving swept tailplane and a large all moving fin. Blown flaps were fitted across the entire trailing edge of the wing to achieve the short takeoff and landing requirement, something that later designs would achieve with the technically more complex swing wing approach. No ailerons were fitted, control in roll instead being implemented by differential movement of the slab tailplanes. The wing loading was high for its time, enabling the aircraft to fly at very high speed and low level with great stability without being constantly upset by thermals and other ground related weather phenomena. The EE Chief Test Pilot, Wing Commander Roland Beamont, favourably compared the TSR 2's supersonic flying characteristics to the Canberra's own subsonic flight characteristics, stating that the Canberra was more troublesome. According to the Flight Envelope diagram, TSR2 was capable of sustained cruise at Mach 2.05 at altitudes between 37000 feet (11278 m) and 51000 feet (15545 m) and had a dash speed of Mach 2.35 (with a limiting leading edge temperature of 140 °C). which would also prove to be one of the reasons for the spiralling costs of the project. Some features, such as forward looking radar (FLR) and side looking radar for navigational fixing, only became commonplace on military aircraft years later. These features allowed for an innovative autopilot system which, in turn, enabled long distance terrain following sorties as crew workload and pilot input had been greatly reduced. There were considerable problems with realising the design. Some contributing manufacturers were employed directly by the Ministry rather than through BAC, leading to communication difficulties and further cost overruns. Equipment, an area in which BAC had autonomy, would be supplied by the Ministry from "associate contractors", although the equipment would be designed and provided by BAC, subject to ministry approval. The overall outlay of funds made it the largest aircraft project in Britain to date. Unlike most previous projects, there were to be no prototypes. Under the "development batch" procedure pioneered by the Americans (and also used by English Electric for the Lightning), there would instead be a development batch of nine airframes, to be built using production jigs. The choice of proceeding to production tooling turned out to be another source of delay, with the first aircraft having to adhere to strict production standards or deal with the bureaucracy of attaining concessions to allow them to exhibit differences from later airframes.

Despite the increasing costs the first two of the development batch aircraft were completed. Engine developmentrefn|The loss of the Avro Vulcan flying testbed aircraft and two ground failures in 1964 resulted in the TSR 2 engine development being far behind schedule. In the days leading up to the testing, Denis Healey, the Opposition shadow secretary for defence, had criticised the aircraft saying that by the time it was introduced it would face "new anti aircraft" missiles that would shoot it down making it prohibitively expensive at £16 million per aircraft (on the basis of only 30 ordered). Test pilot Roland Beamont finally made the first flight from the Aeroplane and Armament Experimental Establishment (A&AEE) at Boscombe Down, Wiltshire, on 27 September 1964. Initial flight tests were all performed with the undercarriage down and engine power strictly controlled—with limits of and 10000 feet (3048 m) on the first (15 minute) flight. Shortly after takeoff on XR219's second flight, vibration from a fuel pump at the resonant frequency of the human eyeball caused the pilot to throttle back one engine to avoid momentary loss of vision. Only on the 10th test flight was the landing gear successfully retracted—problems preventing this on previous occasions, but serious vibration problems on landing persisted throughout the flight testing programme. The first supersonic test flight (Flight 14) was achieved on the transfer from A&AEE, Boscombe Down, to BAC Warton. On flying the TSR 2 himself, Dell described the prototype as handling "like a big Lightning". Over a period of six months, a total of 24 test flights were conducted. Most of the complex electronics were not fitted to the first aircraft, so these flights were all concerned with the basic flying qualities of the aircraft which, according to the test pilots involved, were outstanding. The last test flight took place on 31 March 1965. Although the test flying programme was not completed and the TSR 2 was undergoing typical design and systems modifications reflective of its sophisticated configuration, "[T]here was no doubt that the airframe would be capable of accomplishing the tasks set for it and that it represented a major advance on any other type." There had been some interest in the TSR 2 from Australia for the Royal Australian Air Force (RAAF), but in 1963, the RAAF chose to buy the F 111 instead, having been offered a better price and delivery schedule by the American manufacturer. Nonetheless, the RAAF had to wait 10 years before the F 111 was ready to enter service, by which time the anticipated programme cost had tripled. The RAF was also asked to consider the F 111 as an alternative cost saving measure. In response to suggestions of cancellation, BAC employees held a protest march, and the new Labour government, which had come to power in 1964, issued strong denials. However, at two Cabinet meetings held on 1 April 1965, it was decided to cancel the TSR 2 on the grounds of projected cost, and instead to obtain an option agreement to acquire up to 110 F 111 aircraft with no immediate commitment to buy. This decision was announced in the budget speech of 6 April 1965. The maiden flight of the second development batch aircraft, XR220, was due on the day of the announcement, but following an accident in conveying the airframe to Boscombe Down,

To provide a suitable alternative to the TSR 2, the RAF settled on a combination of the F 4 Phantom II and the Blackburn Buccaneer, some of which were transferred from the Royal Navy. These were the same aircraft that the RAF had derided in order to get the TSR 2 go ahead, but the Buccaneer proved capable and remained in service until 1994. The RN and RAF versions of the Phantom II were given the designation F 4K and F 4M respectively, and entered service as the Phantom FG.1 (fighter/ground attack) and Phantom FGR.2 (fighter/ground attack/reconnaissance), remaining in service (in the air to air role) until 1992. The RAF's Phantoms were replaced in the strike/reconnaissance role by the SEPECAT Jaguar in the mid 1970s. In the 1980s, both the Jaguar and Buccaneer were eventually replaced in this role by the variable geometry Panavia Tornado, a much smaller design than either the F 111 or the TSR 2. Experience in the design and development of the avionics, particularly the terrain following capabilities, were used on the later Tornado programme. In the late 1970s, as the Tornado was nearing full production, an aviation businessman, Christopher de Vere, initiated a highly speculative feasibility study into resurrecting and updating the TSR 2 project. However, despite persistent lobbying of the UK government of the time, his proposal was not taken seriously and came to nothing.