JAS 39 - SAAB JAS 39 Gripen (1992 -     )

This page - Basic information, model kits
Page 2 - Postal Stamps, The prototypes
Page 3 - Other thest aircraft
Page 4  to page 11  -  JAS 39A
Page 11 to page 13 -  JAS 39B
Page 13 to page 15 -  JAS 39C
Page 16                      - JAS 39D

The JAS 39 Gripen is a true multi-role/swing-role aircraft. During the same mission with the same pilot it is able to execute tasks regarding interception, attack and reconnaissance. The aircraft may be configured into the different roles by simply pressing a button. An enemy never knows what kind of opponent he will meet.

The Swedish Air Force has been very demanding. High-technology and high performance have to be combined with a low cost profile. The trend that new aircraft systems constantly were getting more and more expensive, had to be broken. Consequently, the Gripen is 50 percent lighter than its predecessor, the 37 Viggen, but is still capable to carry the same weight of ordnance as the Viggen. Hereby the increased running costs that have been shown to follow an increased weight can be avoided. To get a lighter aircraft, new technologies as composite materials and a high level of  computerization are used.

The Swedish parliament granted in June of 1982 the financial means for the development of the JAS 39 Gripen system. Within the economical limits, also new weapon systems, electronic countermeasures and reconnaissance equipment were to be included. Five major Swedish industrial enterprises, with SAAB taking the largest share, founded ”Industrigruppen JAS” (IG JAS) to develop and manufacture the aircraft. The first prototype flew on the 9^th of December in 1988. The first deliveries to the Air Force started in 1995. F 7 at Såtenäs was the first Gripen Air Force Wing.

The Gripen is like earlier Swedish combat aircraft intended to use the war base system developed by the Swedish Air Force. During wartime, dispersed operations can be executed all around the country, using lengths of straight roads as airstrips. This demands a sturdy aircraft with STOL capability. Gripen is able to land in less than 500 metres. Even in icy conditions, the landing run is less than 800 metres. This is possible by using the moveable canard wing as an air brake. All wheels are fitted with brakes of anti-skid type. The Swedish road base system also includes means for particularly short preparation times between missions. A small team of conscripts, under the command of a technician, makes the aircraft ready in less than ten minutes between two interceptor missions.

The Gripen may be characterized as a delta-winged aircraft with moveable foreplane canards, double horizontal rudders on the leadning edge of the main wing and flaps also on its trailing edge. 25 percent of the structure of the airframe is built of Carbon Fibre Composites. The aircraft is designed to take stresses up to 9 G.

The (tripled) electronic steering system (Flight Control System) facilitates further upgrading of the aircraft with new software. It has also made possible to make the Gripen aerodynamically unstable at subsonic speeds. The computers in the steering (FCS) system constantly compensates the unstable characteristics in a way that the pilot all the time feels that the aircraft is stable to fly. This deliberate unstability gives the aircraft better manouvering performance at all speeds compared with earlier generations of combat aircraft.

The engine is manufactured by Volvo Aero at Trollhättan in co-operation with General Electric in USA. It is a further development of the reliable General Electric F404 turbofan . The Swedish designation is RM 12. The engine delivers a thrust of 8.210 kp (80,5 kN) with reheat. Without the afterburner in function, the thrust is 5.510 kp (54,0 kN). It should be observed that an unstable aircraft with moveable canard wings has a lower air resistance than a conventional aircraft. The thrust is thereby used more efficiently in a configuration like the Gripen, compared with more traditional designs. 

The cockpit is provided with three large  viewing monitors and a HUD (Head-Up-Display). The information is all the time adapted to the varying needs. Great care has been taken to aviod overloading the pilot with irrelevant information. The monitor in the middle shows the position of the aircraft on an electronic chart. The pilot control the aircraft using the HOTAS (Hands-On-Throttle-And-Stick).

A key feature of the Gripen target aquisition/weapon system is the long-range Ericsson PS-05/A multi-mode pulse-Dopple radar.

The Tactical Information Data Link System (TIDLS) makes it possible for all pilots to communicate with fellow aircraft and ground based parts of the Air Defence by encrypted data links. The systems is able to transmit and receive radar images from other aircraft (JAS 39 or the AEW S 100B) or the ground stations. This gives among many other things the pilot the advantage to fly without the radar transmitter of his own Gripen activated. Also the status of fuel and armament of other aircraft can be supervised; an advantage for the Air Commander etc.

The first single seat version of Gripen was sub-designated JAS 39A. A two-seat version, JAS 39B, was developed for training purposes, but also for regular missions when there is an advantage of a second crew member. The Air Force has ordered 204 aircraft - 176 single-seat and 28 two-seat. With the beginning in 2004, JAS 39C (single-seat) and JAS 39D (two-seat) versions will be begin to be delivered. The new versions are adepted to NATO standard. For example, they will have the standard NATO datalink, pylons capable of carrying NATO-standard weapon systems, equipment for refuelling in the air and an oxygen generation system. The instrumentation will be in the English. Altitude and speed will be indicated in feet and knots instead of in meters and km/h.

The cockpit in the newer versions will have have all multi-function displays (MFD) in colour. The MFDs are of great importance to a pilot in a fast moving battlespace. The first Gripen variants were equipped with three 5 x 6,5 inch cathode ray tube displays and conventional stand-by instruments. In the new versions, these will be replaced by three 6 x 8 inch colour LCD displays with integrated back-up modes. This will offer a 90 % display area increase over the earlier system.

Gripen is exported to the Republic of South Africa, the Czech Republic,  Hungary and Thailand.

The JAS 39A Gripen is armed basically by two RB 74 Sidewinder air-to-air missiles and a 27 mm Mauser high-speed cannon for close combat. The two-seater lacks the built-in cannon. Both version can also carry RB 99 (AIM-120 AMRAAM) air-to-air missiles for interception duties.

For ground attack missions, the Gripen, in addition to the built-in cannon is able to carry four different types of weapons. These are the Swedish developed missile RB 15F for targets at sea and RB 75 (Maverick) for ground targets. The other two alternatives are bombs in pod (bombkapsel BK 39) or twenty-four 13,5 cm attack rockets in pods.

A Reconnaissance Pod with full day- and night capacity will be available in 2002. All reconnaissance data will be available to the pilot at the same time it is recorded.

An electronic countermeasures system is installed from the beginning. The aircraft can also be equipped with a pod containing a system to jam enemy radars.

Gripen is the Swedish word for ”Griffin” in English. According to Collins National Dictionary (1966) the Griffin is ”a fabulous beast with eagle’s head and wings and lion’s body; a watchful overseer.”

Photo at top from airshow at F 7,  Såtenäs, May 2009. - JAS 39C # 39269

 JAS 39A: Length: 14,1 m. Span: 8,4 m. MTOW: 12.500 kg. Max. speed: Mach 2

JAS 39B: Length: 14,8 m. Span: 8,4 m. MTOW: 14.000 kg. Max. speed: Mach 2

For the Model Builder

Airfix and Italeri have plactic model kits of both JAS 39A Gripen and JAS 39B Gripen in scale 1:72. To the right you can see the box of the fine Italeri kit of JAS 39A in 1:48 (catalouge number 2638). Click on the thumbnail for larger image.

© Lars Henriksson