Saab JAS 39 Grippen
| JAS 39 Gripen | |
|---|---|
 | |
| Swedish Air Force JAS 39 Gripen | |
| Role | Multirole fighter |
| Manufacturer | Saab AB |
| First flight | 9 December 1988 |
| Introduction | 1 November 1997 |
| Status | Active service |
| Primary users | Swedish Air Force South African Air Force Czech Air Force Hungarian Air Force |
| Unit cost | US$ 40–60 million[1][2] |
In 1979, the Swedish government began development studies for an aircraft capable of fighter, attack and reconnaissance missions to replace the Saab 35 Draken and 37 Viggen. One of Saab's designs was chosen, and was developed into the JAS 39. Comparatively small relative to similar fighters, the Gripen has a top speed of Mach 2. Eight hardpoints allow it to carry various bombs and missiles, supplemented by the 27 mm Mauser BK-27 cannon. Its GE F404-derived Volvo-Flygmotor RM12 produces more than 80 kilonewtons (18,000 lbf) of thrust with afterburner, giving the aircraft a thrust-to-weight ratio of 0.97.
Beset by early problems with its avionics during flight testing, during which a prototype was lost, the aircraft entered service in 1997. Saab has since co-operated with other aerospace companies in marketing the aircraft internationally, and has achieved moderate success in Central Europe, South Africa and Southeast Asia. More than 264 Gripens have been delivered or ordered as of 2011
Development
Origins
By the late 1970s a replacement for Sweden's ageing Saab 35 Draken and Saab 37 Viggen was needed.[4] Sweden needed an aircraft with good short field performance for its dispersed basing plan if the nation was invaded. Mach 2 speed was also desired and it had to be affordable. The aircraft also had to be smaller than the Viggen, but with at least the same payload-range characteristics.[5] A number of foreign designs were studied, namely the F-16 Fighting Falcon, the F/A-18 Hornet,[6] the Northrop F-20 Tigershark and the Dassault Mirage 2000.[7] In the end, the Swedish government opted to build its own fighter, with the task handed to Saab (Svenska Aeroplan Aktiebolag).[6] In late 1979, the government commenced a study calling for a versatile platform capable of "JAS", which stands for Jakt (air-to-air), Attack (air-to-surface), and Spaning (reconnaissance), indicating a multirole, or swingrole, fighter aircraft that can fulfil multiple roles during the same missions.[6]A number of Saab designs were accordingly reviewed, with the most promising being "Project 2105" (redesignated "Project 2108" and later, "Project 2110"), which was recommended to the government by the Defence Materiel Administration (Forsvarets Materielverk, or FMV).[6] The aircraft studied would be a single-engine, lightweight single-seater, which embraced fly-by-wire technology, coupled with an unstable design and canards.[8] The powerplant would be the Volvo-Flygmotor RM12, a licensed-built derivative of the General Electric F404-400; engine development priorities were weight reduction and lowering component-count.[8][9] On 30 June 1982, with approval from Swedish Parliament,[10] the FMV issued contracts to prime contractor Saab covering five prototypes and an initial batch of 30 production aircraft.[8] To test several avionics intended for the JAS 39, such as the fly-by-wire controls, a Viggen was rapidly converted to operate as a test aircraft, flying by January 1983.[11] The JAS 39 received the name "Gripen"[Nb 1] through a public competition, which was announced in 1982;[13] the griffin is the heraldry on Saab's logo.
Testing and production
Sweden first ordered the JAS 39 in 1982; this first order was named Batch One and consisted of 30 JAS 39A single-seaters.[15] The first Gripen was rolled out on 26 April 1987, marking Saab's 50th anniversary.[16] Originally planned to fly in 1987,[9] the first prototype (serial number 39-1) took its maiden flight on 9 December 1988 with pilot Stig Holmström at the controls.[8] During the test programme, concern surfaced about the aircraft's avionics, specifically the fly-by-wire flight control system (FCS), and the relaxed stability design configuration.[8] On 2 February 1989, the problem was highlighted with the crash of the prototype while landing at Linköping;[8] Test pilot Lars Radeström was able to walk way with only a broken arm. The cause of the crash was identified as pilot-induced oscillation (PIO), caused by problems to the FCS's pitch-control routine.[8]
To rectify the problem, Saab undertook major software improvements in conjunction with Calspan from the United States.[8] A modified Lockheed NT-33A was used to test out these changes, and, within fifteen months after the accident, flight testing resumed.[8] The programme was again hindered when, on 18 August 1993, production aircraft 39102 was destroyed in an accident during an aerial display in Stockholm. The pilot Radeström lost control of the aircraft during a roll at low altitude, and the aircraft stalled within six seconds, forcing him to eject.[8] The jet impacted into a small island near thousands of onlookers, but no one was hurt. Saab later found the problem to be high amplification of the pilot's quick and significant stick command inputs.[8] The ensuing investigations and rectification of the flaws delayed test flying by several months, resuming in December 1993.[8]
The first aircraft order also included an option for another 110, which became a firm order in June 1992.[15][17] This was named Batch Two and was made up of 96 one-seat JAS 39As and 14 two-seat JAS 39Bs.[15] The JAS 39Bs were 66 cm (26 in) longer than the A version; the second seat necessitated the deletion of the built-in cannon and a smaller internal fuel load.[15] By April 1994, five prototype Gripens and two series-produced aircraft has been completed; the only major decision left was the selection of a beyond-visual-range missile (BVR) for integration.[18]
A third batch of Gripens was ordered in June 1997. This batch called for 50 upgraded single-seat JAS 39Cs and 14 JAS 39D two-seaters.[15] Batch Three aircraft possess more powerful and updated avionics, in-flight refuelling capability with the provisions of retractable probes on the aircraft's starboard side, and an on-board oxygen-generating system for longer missions.[15] To test the viability of in-flight refuelling, Flight Refuelling Ltd outfitted a prototype (39–4), which was successfully tested with a Royal Air Force VC10 in 1988.[15] Deliveries of this batch ran from 2003 to 2008.[15][19]
Teaming agreements
During the 1995 Paris Air Show, Saab Military Aircraft and British Aerospace (BAe, now BAE Systems) formed the joint-venture company – Saab-BAe Gripen AB – with the goal of adapting, manufacturing, marketing and supporting Gripen worldwide.[15][20] The deal involved the conversion of the A and B series aircraft to the "export" C and D series, which developed the Gripen for compatibility with NATO standards.[21] This cooperation was extended in 2001 with the formation of Gripen International to promote export sales.[22] In December 2004, Saab and BAE Systems announced that BAE was to sell a large portion of its stake in Saab, and that Saab would take full responsibility for marketing and export orders of the Gripen.[23] BAE Systems sold the remaining 10 per cent of their stake in Saab in June 2011.[24]On 26 April 2007, Norway signed an agreement on a joint-development programme of the aircraft regarding co-operation in advanced development work on future versions of the aircraft. The value of the deal, which will allow Norwegian companies to take part, is about NOK 150 million over two years.[25] In June of the same year, Saab also entered an agreement with Thales Norway A/S concerning the development of communications systems for the Gripen fighter. This order for the Norwegian company is the first to be awarded under the provisions of the Letter of Agreement signed by the Norwegian Ministry of Defence and Gripen International in April 2007.[25]
In December 2007, as part of Gripen International's marketing efforts in Denmark, a deal was signed with Danish technology supplier Terma A/S which allows them to participate in an industrial co-operation programme over the next 10–15 years. The total value of the programme is estimated at over 10 billion Danish krone, and is partly dependent on whether Denmark would choose the Gripen.[26]
Gripen NG and recent developments
In 2007, a two-seat "New Technology Demonstrator" was ordered; it was presented on 23 April 2008.[28] It has increased fuel capacity, a more powerful powerplant, increased payload capacity, upgraded avionics and other improvements. The new Gripen NG (Next Generation) is also referred to as the "Gripen Demo",[29] the "Gripen E/F", or MS 21.[30][31] This version has many new parts and is powered by the General Electric F414G, a development of the Boeing F/A-18E/F Super Hornet's engine. The engine produces 20 per cent more thrust at 98 kN (22,000 lbf), enabling a supercruise speed of Mach 1.1 with air-to-air missiles (AAM).[32]
Compared to the Gripen D, the Gripen NG's maximum take off weight has increased from 14,000 to 16,000 kg (30,900–35,300 lb) with an increase in empty weight of 200 kg (440 lb). Due to relocated main undercarriage, the internal fuel capacity has increased by 40 per cent, with a significant increase in range. Combat radius will be 1,300 kilometres (810 mi) with six AAMs plus drop tanks, and 30 minutes on station.[33] Ferry range will be 4,070 km (2,200 nmi) with drop tanks. The new undercarriage configuration also allows for the addition of two heavy stores pylons to the fuselage. Its PS-05/A radar adds a new AESA antenna for flight testing beginning in mid-2009.[32]
Gripen Demo's maiden flight was conducted on 27 May 2008. The test flight lasted about 30 minutes and reached a maximum altitude of about 6,400 meters (21,000 ft).[34] On 21 January 2009, the Gripen Demo flew at Mach 1.2 without reheat to test its supercruise capability.[35]
Saab performed study work on an aircraft carrier based version in the 1990s. In 2009, Saab launched the Sea Gripen project in response to India's request for information on a carrier-borne aircraft. Brazil also has a potential carrier aircraft need.[36][37] Sweden awarded Saab a four-year contract in 2010 to improve the Gripen's radar and other equipment, and lower its operating costs.[38] In June 2010, Saab stated that Sweden plans to order the Gripen NG under the JAS 39E/F designation. The new variant is to enter Swedish service in 2017 or possibly earlier if export orders are received.[31]
By mid-2010 Swedish Air Force's JAS 39C/Ds had received the MS19 upgrade, which provided capability for the long-range MBDA Meteor missile, the short-range IRIS-T missile and the GBU-49 500-lb laser guided bomb.[39] The subsequent MS20 upgrade project includes full Meteor missile capability, and is to span from 2011 to 2013.[40] Next the MS21 (Gripen E/F) project is to begin circa 2015, depending on the needs of a possible foreign partner.[39]
Design
Overview
In designing the aircraft, several layouts were studied. Saab ultimately selected a delta wing-canard design with relaxed stability. The configuration provides for a high manoeuvrability along with better takeoff and landing performance.[41] The Gripen also has a low drag, enabling it to fly faster, have increased range, and carry a larger payload.[41] The totally integrated avionics make it a "programmable" aircraft, changing the software can provide for additional mission profiles.[42]
The Gripen was designed to provide for a fast sink rate and hard, short landings.[43] While lacking thrust reversers that would allow the engine to aid braking, the aircraft's canards can be angled downwards to act as air brakes.[41] The main wing is also fitted with flaps and elevons to change the flow of air around the wing.[42] In addition to being able to take off with up to 14,330 lb of rockets, bombs, or missiles, the Gripen is also equipped with a single 27 mm Mauser BK-27 cannon.[42] Of the aircraft's content, 67 per cent is sourced from Swedish or European suppliers, and 33 per cent from the United States.[2]
Avionics and systems
The Gripen uses the modern PS-05/A pulse-doppler X-band radar, developed by Ericsson and GEC-Marconi, which is based on the latter's advanced Blue Vixen radar for the Sea Harrier (which inspired the Eurofighter's CAPTOR radar as well).[44] The radar is capable of detecting, locating and identifying targets 120 km (74 mi) away,[45] and automatically tracking multiple targets in the upper and lower spheres, on the ground and sea or in the air, in all weather conditions. It can guide several air to air missiles at beyond visual range to multiple targets simultaneously.[46]On 27 March 2009, Saab and Selex Galileo signed an agreement for joint development of the Raven AESA radar based on Selex Galileo's AESA Vixen and PS-05/A.[47] This radar will be able to scan 200° from slightly behind to the left to slightly behind to the right.[48] On 9 September 2009, Gripen International offered the source code of their AESA radar as part of their bid for India's fighter competition.[49] Gripens supplied to South Africa had a large amount of their avionics components, such as the communications and electronic warfare systems, manufactured domestically instead of using standard components.[50]
Starting in 2003, Saab and BAE developed the Cobra Helmet Mounted Display System (HMDS) for both the Gripen and other aircraft, based on the Striker HMDS used on the Eurofighter.[51] By 2008, the Cobra HMDS was fully integrated into the aircraft, available as an option in the export versions and since retrofitted into both Swedish and South African Gripens.[51] Particular attention was paid to the need for rapid and safe detachment of the HMDS in the event of the pilot needing to eject.[52]
The flight controls of the Gripen have been upgraded to use the ADA programming language, which was used on final prototypes and production aircraft from 1996 onwards.[53] The Gripen's software is continuously being improved and changed to add new capabilities, in comparison the Viggen was updated only as per an 18 month schedule.[54] The Gripen was designed to form part of a "networked defence system", large quantities of data are exchanged automatically in real-time between one aircraft and shared with both other Gripen aircraft and command centres on the ground.[55]
Performance
The principle of many parts of the airframe do not require maintenance or are low cost to maintain, as well as the physical structuring of the aircraft, means that Gripen will have a notably longer life than the preceding Viggen, expected to be around 50 years.[54]
Operational history
Sweden
On 29 March 2011, the Swedish prime minister announced that eight Gripens would be deployed to support the UN-mandated no-fly zone over Libya. The Swedish fighters are limited to supporting the no-fly zone and will not perform ground attack sorties.[62] Parts of the media speculate that the Gripen's involvement may encourage sales.[63] On 8 June 2011, the Swedish government announced an agreement to extend the deployment of the five Gripens.[64] As of 24 October 2011, Gripens have flown more than 650 combat missions, almost 2,000 flight hours and delivered approximately 2000 reconnaissance reports to NATO.[65]
Other operators
NATO users
The Czech Air Force and the Hungarian Air Force operate the Gripen; each currently leases 14 ex-Swedish Air Force aircraft, with the option of eventually acquiring them.[66] In December 2001, the Czech Government announced that the Gripen had been selected; and stated that a major factor in this decision was the provision of a generous financing and offset program by Gripen International.[67] Hungary also received an offset arrangement, valued at 110 per cent of the cost of the 14 fighters.[68] Hungary's decision to lease the Gripen came as a surprise, earlier the government had announced the intention to procure the F-16 instead.[69]Initially, Hungary had planned to lease aircraft from Batch II, however the inability to conduct aerial refuelling and employ US guided weapons led to an upgraded variant being developed to meet NATO requirements.[70] The export Gripen underwent refuelling tests in 1998 at Boscombe Down, UK, in response to Hungary's needs.[71]
South Africa
In 1999, South Africa signed a contract with BAE/Saab for the procurement of 26 Gripens (C/D standard) with minor modification to meet their requirements.[21] Deliveries to the South African Air Force commenced in April 2008.[72] By April 2011, 18 aircraft, nine two-seater aircraft and nine single-seater's had been delivered.[73] In May 2011, as allegations of bribery to prevent a possible cancellation of the Gripen procurement continued, Saab issued strong denials over any payments being made.[74] In the following month, Saab announced that payments of around $3.5 million had been made by partner BAE Systems.[75]Thailand
The Royal Thai Air Force ordered six Gripens (two single-seat C-models and four two-seat D-models) in February 2008 to replace some F-5s, with deliveries beginning in 2011.[76] Six more Gripen Cs were ordered in November 2010 with deliveries from 2013.[77] The Gripens are to be based at Surat Thani Airbase.[78] The first of the six aircraft were delivered on 22 February 2011.[79] It is believed that Thailand may eventually order as many as 40 Gripens.[80]Fighter Training Schools
The Empire Test Pilots' School (ETPS) in the United Kingdom has used the Gripen for advanced fast jet training of pilots since 1999.[81]Potential and future operators
- Brazil
- Croatia
- Denmark
- Netherlands
- Switzerland
- United Kingdom
- Others
Missed contracts
- Austria
- Finland
- Germany
- India
The Indian Air Force (IAF) conducted extensive field trials and evaluated Gripen's flight performance, logistics capability, weapons systems, advanced sensors and weapons firing.[121] In April 2011, the IAF rejected Gripen's bid in favour of Eurofighter Typhoon and Dassault Rafale.[122] Senior Indian Air Force officials while happy with the improved capabilities of Gripen NG, identified its high reliance on US-supplied hardware, including electronics, weaponry, and GE F414 engine as a factor that may hamper its export potential.[123]
- Poland
According to a former Polish military defence vice-minister, the JAS 39 offer was better. Saab's offer also included participation in fighter research and technologies.[125][126]
- Norway
On 10 February 2009, Swedish defence minister Sten Tolgfors stated that Norway had miscalculated the deal. The offer was for 48 aircraft over 20 years, but Norway had extrapolated it to operating 57 aircraft over 30 years, thus doubling the cost. The Swedish Ministry of Defence has several other objections to Norway's calculations. Among other things, Norway projected the operational costs for their F-16s on both candidates, and did not consider the operational costs of Sweden's Gripens. Norway also calculated with more aircraft losses in accidents than what Sweden considers reasonable based on their operational experience of the type. According to Tolgfors, Norway's decision will make it more difficult to sell the Gripen to other countries.[133] Tolgfors said that the Gripen does not meet the requirements set by the Norwegian government,[134] though some media reports claim those requirements are tilted in favour of the F-35.[135]
- Romania
Variants
- JAS 39A
- Fighter version that first entered service with the Swedish Air Force in 1996. A modification program has started and 31 of these will be upgraded to C/D standard.[139]
- JAS 39B
- Two-seat version of the A variant. This variant is 0.66 metre (2 ft 2 in) longer than the single seat version.[15] Rear-cockpit does not have a HUD (an image from the front cockpit HUD can be presented on the rear cockpit flight data display), reduced fuel load and no internal gun.
- JAS 39C
- NATO-compatible version of Gripen with extended capabilities in terms of armament, electronics, etc. This variant can also be refuelled in flight.[21]
- JAS 39D
- Two-seat version of the C variant.[21]
- Gripen Demo
- A two-seat technology demonstrator for improvements slated for the Gripen NG.[34]
- Gripen NG/IN
- (Next Generation) Proposed version with new engine (F414G), increased fuel capacity, higher payload, upgraded avionics and other improvements. The Gripen IN version was a contender for the Indian MRCA competition.[118]
- Sea Gripen
- Proposed carrier-based version based on the NG variant;[36][37] currently in development.[107]
Operators
Czech Republic- The Czech Air Force has 14 Gripens on lease, including 2 two-seaters, with all in operation in January 2011.[61]
Hungary- The Hungarian Air Force has 14 Gripens on a lease-and-buy arrangement, including two two-seaters (C/D versions) in service as of January 2011.[61] The final three aircraft were delivered in December 2007.[140]
South Africa- The South African Air Force (SAAF) ordered 26 aircraft (down from 28), 9 two-seater D-models and 17 single-seat C-models.[10] The first delivery, a two-seater, took place on 30 April 2008.[72] The South African Air Force has nine single-seaters and nine two-seaters in inventory as of January 2011.[141]
Sweden- The Swedish Air Force originally ordered 204 aircraft, including 28 two-seaters. Sweden leases 28 of the aircraft, including 4 two-seaters, to the Czech and Hungarian Air Forces. In 2007, the Swedish government stated that only around 100 JAS 39C/D Gripens will be kept in an operational state.[142] The SAF has 120 JAS 39s, including 53 JAS 39As, 10 JAS 39Bs, 45 JAS 39Cs and 12 JAS 39D Gripens in service in January 2011.[61]
Thailand- The Royal Thai Air Force has ordered 12 JAS 39 Gripens (8 single-seat JAS 39C and 4 JAS 39D two-seaters). The first 6 aircraft were delivered in February 2011.[79]
United Kingdom- Empire Test Pilots' School. ETPS instructor pilots and students undergo simulator training with the Swedish Air Force, and go on to fly the two-seater Gripen at Saab in Linköping, in two training campaigns per year (spring and autumn). The agreement was renewed in 2008.[143]
Accidents and incidents
Main article: Accidents and incidents involving the JAS 39 Gripen
As of July 2011, the Gripen has been involved in eight incidents, including five hull-loss accidents, resulting in minor injuries.[144] The first two accidents occurred in 1989 and 1993; these were related to flight control software issues.[145] One aircraft was destroyed in a ground accident during engine testing.[146]Specifications (JAS 39 Gripen C/D)
- Crew: 1 (2 for JAS 39D)
- Payload: 5,300 kg ()
- Length: 14.1 m (46 ft 3 in), two-seater: 14.8 m (48 ft 5 in)
- Wingspan: 8.4 m (27 ft 7 in)
- Height: 4.5 m (14 ft 9 in)
- Wing area: 30.0 m² (323 ft²)
- Empty weight: 6,800 kg[147] (12,600 lb)
- Loaded weight: 8,500 kg (18,700 lb)
- Max takeoff weight: 14,000 kg (31,000 lb)
- Powerplant: 1 × Volvo Aero RM12 afterburning turbofan
- Dry thrust: 54 kN (12,100 lbf)
- Thrust with afterburner: 80.5 kN (18,100 lbf)
- Wheel track: 2.4 m (7 ft 10 in)
- Maximum speed: Mach 2 (2,204 km/h, 1,372 mph) at altitude
- Combat radius: 800 km (500 mi, 432 nmi)
- Ferry range: 3,200 km (2,000 mi) with drop tanks
- Service ceiling: 15,240 m (50,000 ft)
- Wing loading: 283 kg/m² (58 lb/ft²)
- Thrust/weight: 0.97
- Guns: 1 × 27 mm Mauser BK-27 Revolver cannon with 120 rounds (only available on single-seat A/C model)
- Hardpoints: 8 (three on each wing and two under fuselage) and provisions to carry combinations of:
- Rockets: 4× rocket pods 13.5 cm rockets
- Missiles:
- 6× Rb.74 (AIM-9) or Rb 98 (IRIS-T)
- 4× Rb.99 (AIM-120) or MICA
- 4× Rb.71 (Skyflash) or Meteor
- 4× Rb.75
- 2× KEPD.350
- 2× Rbs.15F anti-ship missile
- Bombs:
- 4× GBU-12 Paveway II laser-guided bomb
- 2× Bk.90 cluster bomb
- 8× Mark 82 bombs
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