Structure and Systems
Structurally TSR.2 consisted of five main elements: two centre fuselage sections, the nose section housing the two crew in tandem, the tail section with the fin, and the complete wing. Since about 80% of the fuel was carried in the fuselage, the structure was designed as an integral tank, with fuel in the forward tanks extending aft from the equipment bay to a point between the air intakes, and with rear tanks built around the engine tunnels. Systems and installations were routed through the lower fuselage to improve access.
The light alloy fuselage structure consisted mainly of skin stringer panels supported by transverse bulkhead frames. The panels were largely machined, with chemically etched skins. Tha aluminium alloy DTD5020 was used for frames and panels, RR58 for hotter regions around the powerplants, and the revolutionary X2020 aluminium-lithium alloy was used to skin the airframe. Titanium was used at the 'hot' end of the aircraft around the 'pen nib' and engine heat shields. It is possible that early radar-absorbent materials were incorporated in the structure.
The high-temperature alumino-silicate windscreen was capable of withstanding a 1.2lb (0.5kg) birdstrike at transonic speed.
In the rear fuselage were the two Olympus engines, the engine and jetpipe tunnels for which formed an integral part of the fuselage.
The delta wing was built as a single box and was used as an integral fuel tank. The total amount of fuel carried was 5650 gallons (25425 liters). Two pylons could be fitted under each wing, to carry missiles, bombs, or more fuel; the ferry tanks contained 1213 gallons (5460 liters) each. The fin and the tailplane were of the all-moving type; the tailplane sections could move in unison to provide longitudinal stability, or differentially for lateral control. The twin bogey undercarriage was capable of accepting an emergency landing at maximum take-off weight and, with low pressure tyres, allow operations from unpaved surfaces.
The small, highly loaded wing gave a smooth ride at very low altitude, but to achieve the requested take-off and landing performance, the entire wing trailing surface was fitted with blown flaps. These could be turned down to 50 degrees for landing. For take-off they were set to 35 degrees. Blowing came on automatically when more than 15 degrees of flap was selected.
Four airbrakes were fitted on the aft fuselage, in the narrow gap between the wing trailing edge and the tailplanes. The aircraft also had a braking parachute.
The crew of two sat on Martin-Baker Mk8A zero-zero ejection seats.
Dimensions
The aircraft's overall length was 89 ft ½ in (27.12m), its wing span was 37 ft 1¾ in (11.27m) and it was 23 ft 9 in (7.24m) high. Wing area was 702.9 sq ft (65.3 sq m).
Aircraft empty weight was 54750 lb (24442kg). Take-off weight for an 1125 mile (1800km) sortie would have been about 96000lb (42800kg). Maximum take-off weight would have been about 102200lb (45625kg).
Engines
The engine intakes were of half-circular type, with movable shock cones. There were auxiliary intake doors behind the lips of the main intakes.
The Bristol Olympus 22R Mk.320 was a twin-spool axial-flow engine, with variable afterburner and water injection. It was designed for sustained cruise at Mach 2, a feature which would be used later on Concorde. Each engine was to give 19600lb (87.5 kN) dry thrust, and 30600lb (136.7 kN) with full reheat. An 81-gallon (365-liter) water tank, for injection purposes, was fitted between the jetpipes. An auxiliary power plant was fitted in the fuselage forward of the weapons bay, and this provided low-pressure air for engine starting, AC electrical power for fuel pumps, throttles and the inertial platform, ground running of main engine gearboxes and air conditioning.
Four self-contained hydraulic systems were installed to provide duplicate power controls, and electrical power came from two engine-driven generators, while air tapped from the engine compressors provided pressurisation and air conditioning.
The development of the Olympus 22R engine was not without problems. In December 1962 an engine fitted to a Vulcan testbed exploded during ground running. The event was traced back to a resonant vibration of the turbine, excited by the coolant air flow for the turbine blades. In July 1964 the shaft of an Olympus engine failed during ground testing, requiring more modifications. The engine problems had not been completely cured by the time of the aircraft's cancellation.
Total internal fuel capacity was 5588 gallons. Extra fuel was available in the form of 450 gallon under-wing drop tanks, a 570 gallon tank in the weapons bay and a jettisonable ventral tank holding 1000 gallons under the fuselage. Production aircraft would have had an in-flight refuelling capability.
for operation from austere airfields, TSR.2 featured a 'pop-down' auxiliary powerplant stowed just forward of the weapons bay. This would have been started by an hydraulic motor fed from an accumulator in the aircraft; it would have then started the main engine gearboxes, and furnished electrical and hydraulic power to run fuel pumps and the avionics.
Avionics
Attack
The navigation system was designed to be independent of ground aids. Before take-off the sortie flight plan was fed into the VERDAN digital computer by means of punched tape (VERDAN was an American product developed for the A-5 Vigilante). Navigation was based on dead reckoning using Doppler, the inertial platform and air data computer as sources. The inertial platform was accurate to within two miles in 700, and was updated from the Doppler and the side-looking radar (SLR). In the event of failure the system could continue on Doppler or inertial reference alone.
VERSAN drove a moving-map display in the cockpit, and could fly the aircraft automatically by means of the Automatic Flight Control System (AFCS), which was simultaneously fed with terrain-hugging information from the TFR.
The TSR.2 navigation system
On long sorties the navigator was to obtain an independent fix every 180km or so over well-mapped terrain. The SLAR was to be used for this. The final portion of the nav/attack system was a Ferranti monopulse terrain-following radar which would allow the aircraft to maintain an altitude of 200ft. Ride 'roughness' was adjustable by the pilot. Around 350 hours of terrain-following trials were carried out in a Buccaneer.
The TSR.2 offered the RAF their first high-performance jet with built-in passive electonic countermeasures. This was integrated with the identification and communications systems. The equipment included a complete suite of HF/UHF communications, as well as a sophisticated IFF system known as the 'Special Identification Facility'. A radar warning receiver would pick up enemy EM output and alert the crew to change course or take evasive action, and could even adjust output from the TFR or SLR to minimise the risk of detection. The actual capabilities of most of this kit remain classified.
Reconnaissance
For the reconnaissance role, a pallet could be installed in the bomb bay. This contained a Q-band sideways looking reconnaissance radar, active optical linescan and three FX.126 cameras. In addition, one forward and two sideways looking F95 cameras were permanently fitted in the aircraft's nose. Linescan could be used by day or night, and its data was intended to be transmitted directly to a ground station by radio.
The SLRR could generate high-definition radar maps using its two 15ft antennae in swathes up to 10 nm wide, with enough film to cover a length of 1500nm. The SLRR could also be used to generate Moving Target Indication (MTI) intelligence at lower altitudes, to pick up vehicles moving as slowly as 10mph. In this mode the radar map and MTI imagery would be should side-by-side, simplifying target interpretation.
The TSR.2 Reconnaissance Pack
For high-definition daytime photography the pack's three FX.126 cameras were used. Two were optimised for medium-altitude reconnaissance, with lenses of eitther 36in or 24in focal length, while the third would have been fitted with a 6in focal length lens. These offered the equivalent of a scale of 1:10000 when used at heights of 30000, 20000 and 10000 feet respectively.
Linescanner worked both as a passive daytime and active night-time imaging sensor, using a fast-spinning mirror. At an altitude of 10000ft this scanned successive strips of ground 1nm wide, and projected these onto a photo-electric cell. This device converted the variations in light intensity it received into electrical signals which could be recorded on video tape, or transmitted in near real time to a ground station up to 120nm away by a steerable antenna in the rear of the pod.
At night the system used a high-intensity light which would scan via a second rotating mirror synchonised with the receiving one, thus effectively lighting the scene below line-by-line. Movement of the light spot on the ground was so rapid that it was undetectable. This system produced imagery close to that obtained by conventional cameras, but without needing a photo-flash which would have been detectable.
Performance
The design of TSR.2 was frozen in the autumn of 1962. Basic performance was estimated as follows: cruise speed Mach 0.9 to 1.1 at sea level and Mach 2.05+ at altitude, radius of action 1125 miles (1800km) on internal fuel and 1700 miles (2700km) with underwing tanks, and ferry range 3250 to 4200 miles (5200 to 6700 km). The aircraft was to be capable of operating from semi-prepared strips 3000 to 4500ft (900 to 1350m) long and climb rate was in excess of 50000ft/min (16000m/min) at sea level.
The standard 1125-mile (1800 km) mission was to be flown with a 2000lb (900kg) bomb stowed internally, with a fuel reserve of 5% of takeoff fuel plus eight minutes loiter. Of this radius, 113 miles (180 km) were to be flown at altitude at Mach 1.7, while the 225 miles (360 km) in and out of the target area were to be flown at Mach 0.9 at 200 ft (60m). The remainder of the mission was at Mach 0.92 at altitude. A lo-lo sortie at Mach 0.9 at 200ft (60m) gave a radius of action of 795 miles (1270 km).
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