DEVELOPMENT

When the Jaguar programme was started, it seemed at first sight that Britain and France were setting out to re-invent the Northrop F-5. In theory, the result should have been a modest design with margin­ally supersonic performance-a replace­ment for aging subsonic types used for training and light-strike duties. The air­craft finally built turned out to be a dedi­cated strike type which combines a wing-span slightly shorter than that of the war­time Messerschmitt Bf.109 with the range and payload-carrying capacity of the Lan­caster bomber. In theory, every operator of the ubiquitous Canberra was a potential customer for the Anglo-French warplane. In practice, France chose to concentrate its marketing energies on all-French types such as the Mirage III and Fl families, leaving the promotion of Jaguar to the UK-a nation not renowned for its ability to sell modern military aircraft.

Further development by the British did give the aircraft a degree of multi-role capability, but a proposed "Big-wing ver­sion"-virtually a "poor man's Phan­tom"-was never built. The only major contract for the Jaguar was placed by the Indian Air Force, which plans to procure a total of 116.
Jaguar owes its origin to Royal Air Force and Armee de Г Air requirements of the early 1960s. Britain was in the market for new advanced trainers, while the French air arm also faced the need to replace outdated Dassault Ouragan and Mystere IV fighters used for attack and close-sup­port missions. Initially, the two nations planned national programmes-the ECAT (Ecole de Combat et Appui Tactique) air­craft, and a British AST.362 project in­tended to replace the Hawker Siddeley Gnat and Hunter. Each nation produced its own design, France opting for the Breguet Br.121, while the UK pursued the v.g. British Aircraft Corporation P.45.

Discussions on possible collaboration started in the spring of 1964, with a joint requirement being hammered out during the winter of 1964/5. Combining the two requirements was a difficult task. The UK wanted a supersonic aircraft complete i with advanced avionics, while France would have been content with a simple subsonic design with a minimum of "black boxes".

By the spring, a common approach had been agreed, and a Memorandum of Understanding signed on May 17, 1965, committed the two nations to work on a j collaborative venture based on the Breguet Br.121 design. To handle the task of со- ! ordinating development and manufactur­ing by the two nations, an organisation with the cumbersome title of Societe Europeenne de Production de l'Avion j ECAT (usually referred to as SEPECAT) was set up.

By November 1965 a basic design had been completed, and construction of a prototype started the following summer. Flight testing began on September 8,1968, with the first production example fol­lowing in November 1971. In order to meet the various national requirements, four models were planned. Since the French requirement was more urgent and involved aircraft with simpler avionics, it made sense for the Armee de I'Air to take early-production aircraft, and for de­liveries to the RAF to take place on a later timescale.

First production model to fly was the Jaguar E two-seat trainer for the French Air Force, becoming airborne on September 8, 1968. Jaguar A is the French tactical-support fighter version, and was first flown on March 23, 1969. Both partners had agreed to take 200 aircraft, the French split being 40 E and 160 A versions. A navalised Jaguar M version was planned for service aboard the carriers Foch and Clemenceau. A prototype was flown in November 1969, but the Aeronavale de­cided in 1972 to scrap the project.

The RAF tackled their versions in the opposite order. First to fly, on October 12, 1969, was the Jaguar S strike version (service designation Jaguar GR.1). The Jaguar В (Jaguar T.2) two-seat trainer fol­lowed on August 30, 1971. Early plans assumed that all RAF aircraft would be two-seaters. By 1967 the chosen mix was 110 trainers and 90 strike aircraft, but a 1970 review by the contemporary Conser­vative Government resulted in Jaguar being assigned to the strike role. The final plan involved the purchase of 165 single-seaters and only 38 two-seat trainers to be used for operational conversion.

Production for France and Britain ended in December 1981 with delivery of the final Jaguar A to Armee de Air. All subsequent Jaguars have been for export. Designated Jaguar International, these are based broadly on the RAF-standard air­craft. First export customer was Oman, which ordered 24. The first flew on August 19, 1976. Ecuador ordered 12 aircraft to equip a single squadron, but the main export user is India.

Adoption of Jaguar by the Indian Air Force was a prolonged process. The ser­vice had a long-standing Deep Penetration and Strike Aircraft (DPSA) requirement, and made no secret of its desire to buy Jaguar. Shortage of funds repeatedly de­layed the choice of a DPSA, but the selec­tion of Jaguar was finally announced in 1979.

The first 40 aircraft were delivered from the UK production line, and Hindustan Aeronautics is currently assembling addi­tional aircraft at its Bangalore plant using British-supplied parts. The first locally-assembled aircraft flew in March 1982. India originally planned to assemble 45 Jaguars from British kits, switching to full licence production. Plans for the latter option were cancelled early in 1983, and HAL will now assemble an extra 31 air­craft, bringing the total Indian production run to 76 examples. Production is reported to be running at more than one per month.

Despite a modest unit cost (by today's standards) of between $8 million and $10 million, Jaguar has not received the orders which might have been expected. Latest customer is reported to be Nigeria, which wants 18 aircraft to replace obsolescent MiG-17 and MiG-21 fighters. The original aircraft was a dedicated strike type, but the much-improved Jaguar International offers a degree of capability in the air-combat and air-superiority roles.

STRUCTURE

Dassault is responsible for the construc­tion of the forward and centre fuselage, the forward fuel tanks and the undercarriage, while British Aerospace builds the rear fuselage, air inlets, wing and tail. In order to create the Jaguar, the original Breguet design had to be reworked, growing in length and being modified to use machined panels rather than the honey­comb construction originally proposed. Use of the latter material is confined to the cockpit area.

Most of the fuselage is made from alu­minium alloy, but titanium is used in the engine bays. Airbrakes are mounted low on the fuselage sides, aft of the. main undercarriage doors and directly below the wing trailing edge.

The wing is a one-piece unit with two main spars and 40deg of sweep. No ailerons are fitted, roll control being by means of spoilers which operate in conjunction with the differential tailplane. Double-slotted flaps run the entire length of the trailing edge, while the outer sections of the leading edge are fitted with slats.

A total of 924 gal (4,200 litres) of fuel is carried in two wing tanks and four fusel­age tanks, and critical elements of the fuel system are protected by armour. The only other part of the aircraft to be armoured is the cockpit transparency, which can resist small-arms fire.

POWERPLANT

Like the airframe, the powerplant is a collaborative Anglo-French venture. The RB.172 Adour afterburning turbofan was designed by Rolls-Royce and Turbomeca. Of modular design to ease maintenance, it is a two-spool design with a two-stage LP fan and five-stage HP compressor, both driven by single-stage turbines. The com­bustion chamber is annular with 18 fuel nozzles, while the afterburner is a com­pact but fully-modulated unit.

Standard powerplant on French and UK Jaguars was originally a pair of RB.172 (Mk 102) Adours. Each develops 5,115lb (2,320kg) of thrust, 7,305lb (3,313kg) in full afterburner. France was happy to retain this engine, but the RAF has always considered Jaguar to be underpowered. British aircraft are now fitted with the Mk 104, which offers an extra 205lb (93kg) of dry thrust and 735lb (333kg) with after­burner.

For Jaguar International, the initial pow­erplant was the RB.172-26 (Mk 804)-an export version of the MK 104-but aircraft destined for India and the second batch for Oman have the Mk 811 Adour developing 5,520lb (2,503kg) of dry thrust, 8,400lb (3,810kg) with afterburner.

AVIONICS

Britain and France developed their own avionics installations for Jaguar. The French opted for relative simplicity, while the RAF installed a more sophisticated system which has generally been adopted by export customers.

Main items of avionics in French Jaguar A strike aircraft include an EMD RDN 72 Doppler radar, CSF laser rangefinder, SFIM 153-6 twin-gyro inertial platform, Crouzet type 90 navigation computer, CSF Type 31 weapon-aiming computer, Das­sault fire-control computer, and a radar-warning receiver. Some aircraft carry a Thomson-CSF/Martin Marietta ATLIS laser-designator pod.

UK Jaguar S aircraft are equipped with a Marconi Avionics digital/inertial naviga­tion and weapon-aiming subsystem (NAV-WASS) based on an MCS 920M digital computer, a Marconi Avionics air-data computer, Ferranti Type 105 laser rangefinder and Type 106 marked-target seeker, Smiths Industries HUD, and a three-gyro inertial platform. A fairing in the tail fin houses the antennas for a Marconi Avionics radar-warning receiver.

When Jaguar entered service it was the most complex strike aircraft ever fielded by the RAF, but quickly earned the respect of its crews. Continuously-computed impact point (CCIP) attacks display an average miss distance of 50ft (15m). Parts of NAVWASS are currently being replaced by a new Ferranti FIN 1064 digital nav/ attack system which started flight test in 1981.

India has specified an advanced suite of avionics for its Jaguar force. This includes a new HUD and weapon-aiming system similar to that in Sea Harrier, plus a Ferranti COMED combined map and elec­tronic display. Eight aircraft will be fitted out for maritime strike, with a Thomson-CSF Agave radar in a modified nose and a Ferranti laser ranger in a chin-mounted fairing.

The UK Ministry of Defence is using a single Jaguar to flight test a quadruplex fly-by-wire control system incorporating Mar­coni Avionics flight-control computers and control-surface actuators developed by Dowty Boulton-Paul. Flight tests started in 1982, gradually exploring high-angle-of-attack and relaxed stability. In the current stage and final stage of the programme, the wing planform has been modified to make the aircraft inherently unstable.

ARMAMENT

Five external hardpoints - one beneath the fuselage and two under each wing-allow Jaguar to carry up to 10,500lb (4,763kg) of ordnance. Normal loads can include l,000lb (450kg) bombs, BL755 or Beluga cluster bombs, or launchers for 68mm SNEB unguided rockets. Two 30mm ADEN (UK) or DEFA 533 (France) cannon are mounted internally in the lower fusel­age. Jaguar International can carry two Magic or Sidewinder air-to-air missiles on overwing pylons a location which gives the IR seeker heads a clear field of view in air combat.

Specialised stores carried by French aircraft include the AS.37 Martel anti-radar missile, the new AS.30L laser guided missile (aimed using the ATLIS pod) or the AN52 tactical nuclear weapon. UK Jaguars can carry nuclear weapons, but no details have been released. Harpoon has been offered for anti-shipping use.

PERFORMANCE

Jaguar lacks the Mach 2 performance of rival types such as the Mirage Fl, having a top speed of Mach 1.6 at 36,000ft (11,000m). At the low altitudes for which it was designed, a clean aircraft can comfortably out-run first- and second-gen­eration MiG-21 Fishbeds, and is marginal­ly faster than the third-generation Fish-beds, managing Mach 1.1 at sea level.

The aircraft is in its element at low level. For most of the time, the Adours are running at more than 90 per cent of full rpm, operating at high efficiency. Under the same conditions, a Mach 2 type would be running its engines at a less efficient 70 to 80 per cent of full rpm. This feature, coupled with the low specific fuel con­sumption of the Adour, gives the Jaguar a long range-460nm (852km) hi-lo-hi, and 290nm (537km) lo-lo-lo. These figures assume the use of internal fuel only. H underwing tanks are carried, range is in­creased by 65 to 70 per cent.

A tactical support aircraft needs to be able to operate from short strips. Given a payload of four l,000lb (450kg) bombs, the Jaguar needs only 2,890ft (880m) of runway. Even with eight such bombs, take-off run is only marginally above the 4,000ft (1,200m) airstrip length assumed when the Fairchild A-10 was designed.

Some export customers operate Jaguar as a general purpose fighter, and its per­formance as an interceptor is acceptable. Aircraft fitted with the Adour Mk 804 can reach 36,000ft (11,000m) in 2.5 minutes. The structure is stressed to accept +8.6g, so the pilot is free to throw the aircraft around in combat, as many a USAF fighter pilot has learned to his cost during Red Flag sorties.

OPERATORS

UK (165 Jaguar S and 38 Jaguar B), France (160 Jaguar A and 40 Jaguar E), Ecuador (12 Jaguar International), India (116 Jaguar International on order), Oman (24 Jaguar International), plus Nigeria (18 Jaguar International on order).