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Saab J35J Draken - 35556 - Side Profile View

Saab 35 Draken

sweden flag Sweden (1960)
Fighter Plane – 651 Built

A single-seat, single-engine interceptor/fighter for all-weather conditions, with low double delta wings, the Saab 35 Draken was developed in order to replace the Saab J29 Tunnan and the Saab J32 Lansen. Its first flight took place in 1955, being amongst the most advanced and remarkable fighters of its time. In 1960 it entered in service with the Flygvapnet.

Development of the Draken

Draken development started in 1949, following a requirement by the Flygvapnet for a single-seat cost-efficient interceptor with supersonic capabilities and high climbing rates, able to operate in short airstrips – or even highways, roads and unprepared runways – and easy to operate with high adaptability. As a result of both the requirements and development process, the result was a double-delta winged fighter that became the first European supersonic fighter, and also a high performance air-defence asset for Sweden. And on a similar fashion as the JAS 39 Gripen and JAS 37 Viggen, it was required the Draken to be serviced, refuelled and armed up to ten minutes by untrained ground personnel. A brake parachute was incorporated to reduce landing distance. Interestingly, a prototype was built expressly to test the double-delta wing concept: such was the Saab 210 ‘LilDraken’.

J35J in Flight - Swedish Air Force
J35J in Flight – Swedish Air Force

The Draken is also a product of the needs from a neutral nation willing to keep its neutrality, and geographically placed between the two block. This reason explains the requirements, but especially its high climbing rate capabilities, so to be able to engage high-altitude bombers and fighters – namely Soviet Union bombers and fighters. It also explains the need for STOL capacities, as the Flygvapnet was implementing a system of dispersed bases, asking for highways and roads to be used as airstrips from where the aircraft could be operating, and also to reduce damage and increase survival in case of attack.

Its very unique and remarkable double-delta wing design is also explained by the technical abovementioned requirements, which gave the aircraft very good high and low speed performances. This design made the Draken capable of executing the “Cobra” manoeuvre, and also to stand well against more recent designs, as air exercises in Austria evidenced. During development it was able to unintendedly exceed Mach 1 on its first afterburner flight. It could also sustain a force of 10G turning force. And it also had a safety feature, with the introduction of a ram turbine, placed under the nose, to provide emergency power.

Despite being conceptualized as an interceptor, it performed well in dogfights and was able to undertake ground attack, training, and reconnaissance missions as well. And it proved to be a very tough and resistant design, as it is among the few jet fighter designs to be in service for 50 years. Austria, Denmark, Finland, Sweden and US National Test Pilot School were the operators of the Draken.

The design was so unique that, in fact, the Draken was studied for the design and development of the F16XL experimental prototype.

Between 600 and 650 Draken were built, serving with the Flygvapnet until 1998, with the Finnish air force until the year 2000, the Danish air force until 1993, and the Austrian air force until 2005. The Draken also flew with the Flygvapnet ‘Acro Delta’ acrobatic team.

Design

The Draken is designed as a tailless middle double-delta wing fighter, with a single tail and a single engine (A Volvo Svenska Flygmotor RM6C, bestowing a maximum speed of 2125 km/h / 1,317 mph). Its double-delta wings allow good high and low speed performances. It also provided good fuel and armament capacity. The engine air inlets are located mid-wing at each side of the cockpit, featuring a characteristic egg shape.

Considered an easy-to-fly platform, yet not suitable for untrained pilots given the high sensibility controls, and being prone to ‘superstalls’ as a very stable platform with good low flight.

Although the avionics were in principle basic, the radar was a very sophisticated one – A PS-02/A based on the French radar Thompson-CSF Cyrano – integrated with an Ericsson version of a radar Thompson-CSF Cyrano S6 fire control system. It also incorporated VHF/UHF radio, a radio altimeter, a transponder, an IFF (Identification Friend or Foe) system, and the Swedish version of the Lear-14 autopilot. The seat of the pilot was reclined 30 degrees, similarly like the Viggen, to allow the pilot to resist G-forces. And the cockpit was fitted with air-conditioning and pressurization.

J35J Green Camouflage
J35J Green Camouflage

The engine in combination with the design, made the Draken a very manoeuvrable and fast fighter jet, with the braking parachute assisting the aircraft in the landing, reducing the distance required to reach a full stop. Earlier version of the Draken had two 30 mm Aden M/55 cannons, with later versions having only one cannon. Also some export versions kept the two cannons configuration.

An Advanced Cold Warrior

The Draken can boast not only being a radical and new design thus making it a very advanced one by the first decades of the Cold War. It was among the first fighters in incorporating an on-board radar and the earlier version of the data-link system, whose enhanced version was incorporated in the J 37 Viggen and the JAS 39 Gripen. Indeed, the Draken incorporated the STRIL 60 ground-control network that enable Draken pilots a firing guidance through the on-board instruments, being the system also capable to resist electronic jamming. Aside the fact of being the first European supersonic jet fighter, the Draken was the first fighter to have STOL capacities, and it was an aircraft that gathered valuable intelligence by producing photographic material of many new Soviet aircraft during the 70’s and 80’s. It also had a superior service ceiling in comparison with fighters of its times. Being a very resisting and long-endurance fighter, many pilots of the Draken stated that it was able to take on much newer designs.

Variants

  • J 35A – The first version of the Draken. Capable of performing fighter tasks. A small retractable wheel was placed on the rear fuselage as the angle of the nose was required to be elevated during landings to stop the airplane. But the wheel was also placed as the fuselage was enlarged, as the EBK 66 afterburner was incorporated. This version had 2 Aden 30mm cannons, installed on each engine air take, 2 to 4 Rb 24 (Swedish version of the AIM-9B Sidewinder missile) and a central fuel tank or an additional Rb 24. The afterburner installation allowed the Draken 35A to carry Bofors 135mm rockets (up to 12) in rocket pods. This version had basic avionics, being upgraded with the SB6 fire-control system, which included an infrared search and track sensor (IRST). 90 aircraft produced.
  • J 35B – Interceptor and fighter version. Its development began in 1956, before the J 65A was developed. It initially performed training task until better engines and avionics were available. This model then incorporated the air-to-ground STRIL 60 system, and new radar and fire-control systems that enhanced collision course interceptions. It had an ejection seat that allowed the pilot to eject at zero altitude. This version was armed with two 75mm Bofors cannons, folded-fin air-to-air unguided rockets, and for ground-attacks, 135mm rockets. 73 produced.
  • Sk 35C – Trainer version. Two-seat aircraft build upon J 37A airframes, being exported to Denmark and Finland. The second section was raised for the instructor’s place – being located right behind the pilot/student – and fitted with a 3D stereoscopic periscope. Upgraded with afterburners and improved avionics. The tail section was shortened, and the aircraft could be easily re-modified to its J 35A version if necessary. 25 delivered.
  • J 35D – Fighter version, equipped with a better engine – a Svenska Flygmotor RM6C – that made this version the fastest (up to Mach 2), which allowed increased payload, but also meant increasing fuel capacity. Its avionics were also upgraded, receiving a Saab FH-5 autopilot, an Ericsson PS-03 radar coupled with a Saab S7A fire-control system and a new ejection seat, replaced latter with a seat that allowed ejection on zero/zero conditions. 120 delivered.
  • S 35E – Reconnaissance version. It was unarmed but equipped with ECM measures. Fitted with seven cameras: a vertical-looking camera; a forward-looking camera on the nose; a downward/vertical looking with wide-angle camera and two sideways-looking cameras; and two long focal length vertical cameras. A downward-looking periscope and a voice recorder were fitted to allow the pilot to aim the cameras and make comments on the imagery. Latter improved with afterburners, chaff dispensers and two radar alerts, and the ability to carry on the central pylon a night-time Vinten Blue Baron multisensory night photography device. 60 delivered.
  • J 35F – Fighter version. It had improved avionics and electronics, such as integrated radars, radios, aim, infrared target seekers, and missile systems. In fact, it had the STRIL 60 incorporated. It was the version with enhanced armament, such as two semi-active radar homing Rb 27 AAM missiles, and two Rb 28 or Rb 24 AAM missiles. As a result of the new avionics, the second 30 mm cannon was supressed. Used by 18 squadrons in the Flygvapnet. 208 delivered.
  • J 35F2 – A J 35F fitted with a Hughes Aircraft Company N71 infrared sensor.
  • J 35J – Fighter version that kept the Draken in the inventories of the Flygvapnet, co-operating with the J 37 Viggen. It has six pylons, which increased the payload. It incorporated enhanced fire-control systems, infrared sensors, radar, altitude warning systems, navigation systems, IFF and modernised cockpit electronics. It also had a slightly improved RM6C engine that provided more speed. 76 delivered.
  • 35H – Proposed export version for Switzerland. None built or delivered
  • 35XD – Export versions for Denmark. It comprised the F-35 strike aircraft, TF-35 two-seat trainer and the RF-35 reconnaissance jets. Overall the 35XD were the heaviest aircraft of the Draken family, as they were optimized for strike missions. 51 delivered.
  • 35XS – Export version for Finland, some of which were locally assembled by Valmet under license in Finland. The received/assembled aircraft were the interception, fighter-bomber and training versions. 48 delivered.
  • 35BS – Used J 35B bought by Finland
  • 35FS – Used J 35F bought by Finland
  • 35CS – Used Sk 35C bought by Finland.
  • 35Ö – Version for Austria. Used J 35Ds that were refurbished and modernised by Saab, with extra 1000 flying hours, radar warning receivers, the radar of the J 35D, and chaff dispensers. Like the earlier version of the Draken, it was armed with the two 30 mm Aden cannons. 24 delivered.

Operators

  • Sweden – The Flygvapnet had 544 Draken: 90 J 35A; 73 J 35B; 25 Sk 35C; 120 J 35D; 60 S 35E; 208 J 35F; and 76 J 35J. Many were upgraded or modified airframes, so the number is an approximation. Many were sold to other countries.
  • Austria – The last exporter of the Drakens. The Österreicher Luftstreitskräfte received 24 J 35Ö – ex-Swedish J 35D – to replace the J 29F Tunnan in 1987. Initially many Draken (5 Sk 35C) remained in Sweden for training purposes, being replaced later by a simulator. The Austrian Draken were originally armed with two 30mm Aden cannons, as AIM missiles were restricted by a treaty after WWII. But as the crisis escalated in former Yugoslavia by 1993, deeming that cannons were not enough to protect the airspace, Austria acquired AIM 9P3 and AIM 9P5 Sidewinder missiles from the US and equipped them on the Draken.
  • Finland – The second exporter of Drakens, receiving 12 all-weather J 35XS interceptors, 7 ex-Swedish J 35BS, 24 ex-Swedish J 35FS and 5 ex-Swedish Sk 35CS, all to serve with the Suomen Ilmavoimat. Most of the received aircraft were delivered in kit form and assembled by Valmet in Finland, and had also two Aden 30 mm cannons. Finland used the Draken as interceptors and fighter-bombers, and retired them in 2000.
  • Denmark – The first country in exporting the Draken, with units being received in 1970. As the original version was the least favoured during the competition for a new Danish fighter, Saab created a new version (J 35XD), based on the J 35F. the structure was strengthened in order to allow more payload – 9 reinforced pylons – with simultaneous use possible. The landing gear was reinforced with an added arrestor hook, and had two Aden 30 mm cannons, as well as extra fuel capacity. Being a European cost-effective platform, plus the improvements, made the Kongelige Danske Flyvevåben to choose the Draken. 20 A 35XD ground attack fighters (denominated F35), 30 S 35XD reconnaissance (denominated RF35), and six Sk 35XD training (denominated TF35) were purchased. 7 additional aircraft were purchased to be cannibalized. Danish training and reconnaissance versions were fitted with cannons and pylons to carry weapons, thus having secondary combat capabilities. 5 further Drakens (TF35) were purchased. Receiving upgrades in the following years, the Draken were retired from Danish service in 1993.
  • US National Test Pilot School – Operated 6 Drakens, formerly Danish Air Force jets training and reconnaissance versions.

Draken Specifications

Wingspan 9.42 m / 30 ft 10 in
Length 15.20 m / 49 ft 10 in
Height 3.8 m / 12 ft 7 in
Wing Area 49.22 m² / 529.8 ft²
Engine 1 Svenska Flygmotor Turbofan RM6B
Maximum Take-Off Weight 10,089 Kg / 22,200 lb
Empty Weight 6.590 kg / 14,500 lb
Loaded Weight 16,000 kg / 35,273 lb
Maximum Speed 1,900 km/h / 1,200 mph
Range 3,250 Km / 2,020 miles
Maximum Service Ceiling 18,000 m /59,100 ft
Climb Rate 200 m/s ( 12,000 m/min / 40,000 ft/min )
Crew 1 (pilot)
Armament • 1 Aden 30mm Cannon
• 6 hardpoints that could allow 1700 kg of payload. A pod for a 135mm Bofors M70 rockets; air-to-air Rb 24, Rb 27 or Rb 28; external fuel tank; iron bombs; cameras.

 

Gallery

Saab J35J Draken - 35556 - Side Profile View
Saab J35J Draken – 35556
Saab 35Ö Draken - 351408 - Side Profile View
Saab 35Ö Draken – Austrian Air Force
Austrian Air Force Saab J35Oe Draken 351421
Saab J35Ö Draken – Austrian Air Force

Sources

Ängelholms Flygmuseum (n.d.). Flygplan J65 Draken Operational History.Boyne, W (December 2011). Airpower Classic. J35 Draken. Air Force Magazine, 94 (12), 68.Cpt. Moore, V. (2005). A Dragon’s Farewell. Warbirds, 28 (8), 12-16., Guerras del Siglo XX (1994). Guerras del Siglo XX, Aviones. Madrid, Spain: Editorial Altaya., Liander, P. (1999). Draken pensionerad. FlygvapenNytt, (1), 24-27.Martin, G. (2012). The Draken: One of Sweden’s finest fighters. Aircraft Information.Piccirillo, A. C. (2014). Elegance in Flight. Washington, DC: National Aeronautics and Space Administration., Sharpe, M (2001). Jets de Ataque y Defensa [Attack and Interceptor Jets, Macarena Rojo, trans.]. Madrid, Spain: Editorial LIBSA (Original work published in 2001)., WarbirdsUpdate (2013). The Swedish Air Force Historic Flight from Within the Cockpit. Warbirds News., Saab 35 Draken. (2016, April 2). In Wikipedia, The Free Encyclopedia.Winchester, J. (2012). Jet Fighters: Inside & Out. New York, NY: Rosen Publishing.X-Plane.org (2008). Dispersed Basing. X-Plane.org., Images: Draken in Flight by Alan Wilson / CC BY-SA 2.0, J35J Draken Exhibit by Alan Wilson / CC BY-SA 2.0

 

Saab Viggen - Takeoff

Saab S37 Viggen

sweden flag Sweden (1971)
Multirole Fighter Plane – 329 Built
The Saab Viggen is a single-seat, single-engine fighter with a low double delta wing and with two canards equipped with flaps, intended to replace the Saab J35 Draken. Its first flight took place in 1967. When it entered service in 1971 with the Flygvapnet, the Swedish Air Force, it was the most advanced fighter jet in Europe until the introduction of the Panavia Tornado (1981). It was also the first canard-designed aircraft to be produced in a large quantity.

Development of the Viggen

Development for the Viggen began in 1952, with the development period of 1958 to 1961 being crucial for the airplane, as it was decided to integrate the System 37 as standard arms control. This system would end integrating radar, air-defence screens (Stril 60), and computers, and the Viggen were intended to be the platform for such system. This system made the aircraft extremely advanced in comparison to other designs. Along with the Draken it was the precursor to the advanced datalink system the Gripen would later incorporate. Like most of Swedish designs, it also had short taking-off landing (STOL) capabilities (500 meters), thanks to canards, a thrust reverser – that allowed the aircraft to reverse on the ground, and an afterburner to facilitate short take offs. The engine and the remarkable HUD capability also assisted in landing operations.

Interestingly, it can withstand a force of 12G, but operational limit is 7G. It is also a multirole aircraft. However the multirole ability resides more in a basic airframe giving way to different versions: fighter-bomber, attack, tactical reconnaissance, sea reconnaissance, training, and fighter. Given the specific defence conditions of Sweden, the aircraft was required to be easily maintained and serviced by airmen with little training, within a time of 10 minutes.

329 Viggens were built, and served in the Flygvapnet until 2005. Noteworthy to mention that the Swedish Air Force was the main and only user of the Viggen. Agreements with the United States provided technology enough to increase the performance of an already advanced fighter, making it one of the most advanced during most of its service life.

Design

Saab Viggen - BankingThe Viggen is designed as a low double delta wing fighter, with a single tail and a single engine (A Volvo Turbofan Flygmotor RM8B, the most powerful installed in a jet fighter upon its introduction, achieving a maximum speed of Mach 2. It has canards with flaps that provide lift for both flight and taking-off and landing. Assessed as a very stable platform with good low flight, the canards and the combination of the engine, the thrust reverser, the HUD, and the afterburner allows for STOL capabilities (Taking off: 400 mts/ 1310 ft; landing: 450-500 mts/1640 ft).

The wings were provided with dogtooth at the attack border, in order to improve stability at high incidence angles. The structure was built with aluminium with a honeycomb structure, with the rear being totally of aluminium, allowing the Viggen to withstand the stress of no-flare landings, while the vertical stabilizer, or tail, was made tall given the requirements the large anti-ship missiles existing back then imposed on the design. It has a “hump” on the dorsal area to reduce drag. An interesting feature of the tail is that it can be folded, so to enhance the storage in underground and/or smaller hangars. Earlier version of the Viggen did not have an internal cannon, as it was considered by the days a close-range combat was not necessary, an approach that also affected other designs, such as the American Phantom F4. Further variants incorporated an internal cannon. The pilot seat was angled by 19 degress so to allow the pilot to resist better G forces.

A Cold Warrior with Digital Features

Saab Viggen - CockpitThe Viggen was intended to be a single pilot fighter, making the introduction of advanced avionics a requirement as there would be no navigator. As a result, the Viggen incorporated the CK 37 (Centralkalkylator) computer, the first airborne computer with integrated circuits, and that even remained in service with the Flygvapnet fleet of Viggens until the early years of the 21st century. During the development of the Viggen’s electronic components, operational aspects like vibration, exposure to strong forces and even crashes were considered, resulting in a very strong computer with a strong hardware capable of resisting crashes while keeping valuable information of the aircraft. It was also a very valuable computer for the Viggen, as it was able for assisting the pilot and aircraft missions and control of the aircraft.

Another important avionics element of the Viggen, working in tandem with the integrated computers, was the radar, an Ericsson PS-37 X radar. This radar was able to perform air-to-ground and air-to-air telemetry, search, track, terrain avoidance and cartography tasks. The further versions of the Viggen received enhanced avionics and electronic/digital components, enhancing their capabilities and mission performance.

Guardian of Neutrality

The Viggen is a pure product of the times it was designed and the context in which Sweden was a neutral country forced to increase its military power in order to safeguard its neutrality during the heated days of the Cold War. As Sweden was a close neighbor to the Soviet Union, many incidents between the two nations took place. Those incidents prompted Sweden to have an alert service, with round-the-clock radar surveillance, fighters and attackers on high readiness for combat, among other measures. The design therefore was intended to meet the defence needs of Sweden and the missions of the Flygvapnet.

Saab Viggen - TakeoffA first requirement was for the Viggen to have STOL capabilities, so to be able to operate from damaged runways – or runways and highways – and also from secondary airfields. The aim of such operational conditions was to increase the survival of air assets and to difficult the destruction, blocking or dispersion of such assets by an aggressor. A second requirement was the Viggen to be serviced, refuelled and rearmed in less than ten minutes by untrained personnel. This, considering that Sweden’s particular defence conditions required small and dispersed air and field bases, having little personnel and facilities. In fact, and thanks to this system, the Viggen was able to execute up to 11 sorties within a period of 24 hours. In addition, the Viggen became the main asset of Swedish air defence, intercepting, patrolling, and monitoring Soviet and Western activities and flights. This explains the multi-role capacities of the Viggen, or at least to have served as a basis for different versions using the same airframe. It also allowed Sweden to demonstrate its readiness. During the S-137 Soviet submarine incident, the submarine ran aground on the Swedish archipelago and Soviet surface vessels closed in on the Swedish coast to attempt a rescue, armed Viggens were put into the air so to ward-off the Soviets. Also, with the routine of the American SR 71 Blackbird path known, the Viggen was able to get radar-lock on the SR71 despite the jamming measures of the reconnaissance plane and thanks to coordination with ground-based radars. It is the only aircraft that managed to lock onto the SR 71.

Variants

  • AJ 37 – An all-weather attack aircraft with air-to-air secondary capacity. Considered outdated, it lacked a gun, but had increased bombing precision thank to its HUD and Weapons Aiming Computer System. Armed with rockets and iron bombs for strike missions, and Saab 305/Rb 05 or Sidewinders and 30mm cannon pods for air-to-air. It also had anti-ship capabilities thanks to the Saab 304 anti-ship missile. 108 delivered.
  • Sk 37 – Training version, with a second cockpit and the avionics and fuel removed, also lacking a radar array. It had instead of the internal fuel tank, a permanent fuel tank under the belly. It also had a shorter range. The second cockpit has two periscopes to provide forward view. It was tasked with providing pilots conversion and supersonic training. It also had secondary combat capacities. 10 were converted to electronic warfare trainers (SK 37E). 17 delivered.
  • SF 37 – All-weather reconnaissance version and intended to substitute the S35E. The nose had a peculiar form thanks to the fact that the recce equipment was placed there, with seven cameras. On the hardpoints further reconnaissance equipment was placed. One camera can take infrared pictures, two vertical cameras can take shots for high-altitude, and four cameras for low-altitude shots. It had the same armament as of the JA 37 interceptor version yet lacking of radar. 28 delivered.
  • SH 37 – Single seat version fitted for sea surveillance and attack/anti-ship roles, armed usually with the Saab 305 anti-ship missile and other ground-attack weaponry. It could also carry Sidewinder missiles for self-defence. 28 delivered.
  • JA 37 Jaktviggen – All-weather interceptor version of the Viggen, powered with a Flygmotor RM8B. Incorporated an internal 30 mm Oerlikon cannon, and could operate AMRAAM, Sidewinder or Rb71 Sky Flash missiles. Armed also with radar and infrared homing missiles. It also had upgraded avionics, such as a long-range Ericsson UAP-1023 pulse Doppler radar, enhancing target acquisition, and new computers that enhanced as well the aircraft performance. In fact, there is a coupling of radar gunsighting with the autopilot, presenting a lock information to the pilot’s HUD while increasing the cannon lock thus reducing the workload for the pilot. It also had an inertial navigation system. Furthermore, it provides tracking for land, air and sea-borne targets while resisting to ECM attacks. Some were upgraded with airframes, avionics and software modified for international duties (JA 37C, JA37D, and JA37DI) 149 delivered.
  • Saab 37 Eurofighter – Proposed replacement for NATO F-104 Starfighter. None built.
  • Saab 37 X – Proposed version to be exported to Norway. None built.

Operators

  • Sweden – The Flygvapnet has 329 Viggens, 108 of which are AJ 37, 17 were Sk 37, 28 were SF 39, 28 were SH 37, and 149 were JA 37.

Viggen Specifications

Wingspan 10.6 m / 34 ft 9 in
Length 16.40 m / 53 ft 9 in
Height 5.6 m / 18 ft 4 in
Wing Area 46 m² / 500 ft²
Engine 1 Volvo Flygmotor Turbofan RM8
Maximum Take-Off Weight 20,500 Kg / 45,194 lb
Empty Weight 11,800 kg / 26,014 lb
Loaded Weight 16,000 kg / 35,273 lb
Maximum Speed 2,125 km/h / 1,320 mph
Range 2000 Km / 1,242 miles
Maximum Service Ceiling 18,000 m /59,100 ft
Climb Rate 203 m/s ( 12,000 m/min / 40,026 ft/min )
Crew 1 (pilot)
Armament • 1 Oerlikon KCA 30mm cannon (JA 37)
• 7 hardpoints that could allow 6000 kg of payload. A pod for Aden 30 mm cannon; 135mm Bofors M70 rockets in pods for six rockets; air-to-air Saab 305/Rb 05, Rb71 Sky Flash, AMRAAM or Sidewinder missiles; air-to-surface or Maverick missiles; Anti-ship Saab 304; 120 kg iron bombs.

Sources

Anrig, C. F (2005). Flygvapnet, The Swedish Airforce in an Era of Transition. Air Power Revue, (4) 36-44.Ängelholms Flygmuseum (n.d.). Flygplan J37 Viggen., Berger, R (Ed.). Aviones [Flugzeuge, Vicenç Prat, trans.]. Colonia, Alemania: Naumann & Göbel Verlagsgessellschaft mbH., Boyne, A (July 2014). Airpower Classic. JA37 Viggen. Air Force Magazine, 97 (7), 76.Lemoin, J (2002). Fighter Planes. 1960-2002., Groebel, G (2016). The SAAB 37 Viggen., Jiewetz, B (n.d.). Central Computer for aircraft Saab 37, Viggen. DATASSABs Vänner.SAAB (n.d.). Saab 37 Viggen. Brochure., Sharpe, M (2001). Jets de Ataque y Defensa [Attack and Interceptor Jets, Macarena Rojo, trans.]. Madrid, Spain: Editorial LIBSA (Original work published in 2001)., WarbirdsUpdate (2013). The Swedish Air Force Historic Flight from Within the Cockpit. Warbirds News., Saab 37 Viggen. (2016, May 1). In Wikipedia, The Free Encyclopedia., Gunston, Bill and Mike Spick. Modern Air Combat: The Aircraft, Tactics and Weapons Employed in Aerial Warfare Today. New York: Crescent Books, 1983. Images: Saab Viggen Banking by Alan Wilson / CC BY-SA 2.0, Saab Viggen Intake by Houser Wolf / CC BY-ND 2.0, Saab Viggen Gear by Alan Wilson / CC BY-SA, Saab Viggen Takeoff by Alan Wilson / CC BY-SA, Saab Viggen Cockpit by Per80 / CC BY-SA 3.0, Saab Viggen Engine Inspection by Rune Rydh / Flygvapenmuseum / CC BY 4.0

Gallery

SAAB Gripen Armed In Flight

Saab J39 Gripen

sweden flag Sweden (1997)
Multirole Fighter Plane – 247 Built
A light single-engine multirole fighter, with a delta mid-wing and canard configuration. This aircraft has a fly-by-wire flight controls. Purposed with replacing the Saab 35 Draken and Saab J 37 Viggen AJ, SH, SF and JA versions in service with the Flygvapnet (the Swedish Air Force), and in service since 1995. Its development began in the late 70’s, with the aircraft intended to perform the same missions of the models it was replacing. As a result, the Gripen is capable of executing missions as fighter, attacker, and reconnaissance, being also a cheap yet well-powered and highly manoeuvrable jet, capable of integrating well with the Flygvapnet communication and infrastructure systems. It is also a platform with good upgrading capacities. Another special feature of this model is the short take-off and landing (STOL), alongside its agility and responsiveness at subsonic speeds, low induced drag and good supersonic performance. A product of Swedish innovation and defence needs, allowing Sweden to maintain its neutrality during the Cold War, the aircraft’s STOL characteristic came as a result of the policy of using highways and roads as airstrips, in order to reduce the potential damage to Flygvapnet air assets in case of attack, and to maintain air defence capacity. It was also intended to be an easy maintenance airplane, with conscripts having basic technical knowledge being able to do maintenance works. This increases the aircraft’s service life.

Design

The Gripen is designed as a mid-delta wing fighter, with a single tail and a single Volvo Flygmotor RM 12 engine. It has canard winglets that also serve as complement for the two aerodynamic brakes located at the sides of the rear fuselage. The combination of the canards and the delta wing design allows the Gripen to fly at 70-80 degrees of attack angle, allowing also STOL capabilities (800 mts/2600 ft airstrip). Its purposed aerodynamic instability is compensated with a fly-by-wire technology that bestows the Gripen with considerable fly characteristics. The engine also plays its part in shaping the Gripen characteristics, along with some additional features. The double digital control and double ignition allows the pilot and the aircraft to be safe in case of emergency. The engine itself is reinforced to withstand the impact of birds or foreign objects. The radar – an Ericsson pulse-Doppler – allows the Gripen to have powerful and sharp ‘eyes’, as it allows multiple target track and beyond visual range (BVR) for air-to-air; mapping ground and surface target indication and tracking for air-to-ground; and sea surface search and tracking.

The Digital Era

SAAB Gripen Parked

The JAS 39 has a Tactical Information Data Link System (TIDLS) digital network which provides the Gripen with a tactical advantage: to distribute and share radar and sensors information with up to 4 aircraft within a radio of 480 kms (300 miles), enabling tactical combat information and situation awareness. It also provides any pilot information about the position, speed, missile load, heading and fuel state of other Gripens. This provides also concealment to any pilot opening fire against a selected target, without revealing its position, while the launched missile – a medium-range air-to-air-missile (AMRAAM) – will be guided not only by the aircraft it was fired from, but also by the other aircraft, whose guidance can improve the missile’s accuracy. TIDLS technology however, is not a product enjoyed only by the Gripen’s development, but it is an enhanced version, as the JAS 35 Draken and JAS 37 Viggen had a similar and early datalink systems. As it is a multirole aircraft, this means it can change its mission while flying, as the pilot change the avionics and sensors in flight. Although the small size of the plane limits these capacities and payload, forcing missions to be considered before sorties, it also allows the aircraft to reduce detection by radar.

The Gripen goes to Battle 

SAAB Gripen Armed In Flight

The high adaptability and capacity of the aircraft to be easily upgraded allowed the Gripen to be modified in order to fit NATO standards, and to increase its export options. Alongside the British BAE, Saab improved and modified the Gripen so to be able to operate with NATO missiles, opening the open for the aircraft to carry more powerful missiles, and having also enhanced air-to-ground capabilities. Those modifications allowed the Gripen to support NATO intervention in Libya (Operation Unified Protector) with tactical air reconnaissance, enforcement of the no-fly zone, the arms embargo, and support for civilian protection. It was also able to receive updates and information from NATO E-3 AWACS airplanes. The Gripen performance was optimal during the operation, as it flew 570 missions, around 1770 flight hours, and delivered 2770 reports.

A Coveted Fighter

Saab Gripen Taxiing

Given its characteristics and its good relation cost/operation, the Saab JAS 39 Gripen has received the attention of many countries that expressed their interest in the fighter. Countries like Argentina, Austria, Belgium, Botswana, Bulgaria, Colombia, Croatia, Ecuador, Estonia, Finland, India, Indonesia, Kenya, Latvia, Lithuania, Malaysia, Mexico, Namibia, Peru, The Philippines, Portugal, Serbia, Slovakia, Slovenia, Uruguay, and Vietnam, all could become potential operators of the Gripen.

Variants

  • JAS 39A – The basic and first version entering in service with the Flygvapnet, later upgraded to the C version.
  • JAS 39B – The two-seated variant of the JAS39A, purposed for training, specialised missions and flight conversion, with the cannon and the internal fuel tank removed to allow the second crew member and life support systems.
  • JAS 39C – A NATO-compatible version with overall enhanced capabilities, as well as in-flight refuel.
  • JAS 39D – The two-seat version of the JAS 39C.
  • JAS NG – An improved version of the Gripen, having a new engine (The General Electric F414-400), a new radar (RAVEN ES-05 AESA), and increased payload and fuel capacity. Its development was undertaken through a partnership with Switzerland. A product of the changes brought by the end of the Cold War, as airbases were closed with fighter units being reduced, as well as the closure of the road base system for take offs and landings. But it is also a product of the new assessed threat Sweden could be facing, which required a new fighter with extended range, increased weapons, enhanced electronics, fighter communications (with satellite) and Electronic Warfare (EW) capability.
  • JAS 39E– Single seat version derived from the JAS NG.
  • JAS 39F – Two-seat version derived from the JAS 39E.
  • Sea Gripen – Proposed carrier version of the NG.
  • Gripen UCAV – Proposed unmanned combat version of the JAS 39E.
  • Gripen EW – Proposed electronic warfare version derived from the JAS 39F.

Operators

  • Brazil – 28 Gripen JAS 39E and 8 Gripen JAS 39F on order, with options of assembling some locally, while the Brazilian Navy is interested in the Sea Gripen for use on its single aircraft carrier. Brazil could export Gripen into the regional market. There is a provision for joint development with Sweden.
  • Czech Republic – 14 Gripens on lease (12 JAS 39C and two JAS 39D) until 2027 and to replace the existing Mig 21 fleet. given the current tensions between the West and Russia, Czech Republic government considered leasing 6 more Gripens. Gripen have had a good use by the Czech Air Force, with membership of the NATO Tiger Association, awarding the Tiger Meet Silver Tiger Award as ‘Best Squadron’. Gripen from Czech Republic also take part in NATO Baltic Air Policing, while performing homeland defence duties at the same time.
  • Hungary – 12 Gripens on a lease-and-buy basis (11 JAS 39 C and one JAS 39D) until 2022. Two Gripens lost in crashes. Hungarian Gripens have been taking part of NATO Baltic Air Policing since 2015.
  • South Africa – 26 Gripens are in service with the South African Air Force (17 JAS 39C and 9 JAS 39D), facing restricted operation given lack of qualified pilots and financial resources. However, South African Gripens enjoyed a local EW development – in cooperation with Israel – and datalink, as well as radar weather mode. The Gripens saw action when securing South African airspace during the FIFA 2010 World Cup, supporting South African troops in the Democratic Republic of Congo in 2013, and taking part in Nelson’s Mandela funeral.
  • Sweden – The Flygvapnet has 156 Gripen, 50 of which are JAS 39A, 13 are JAS 39B, 60 are JAS 39C and 11 are JAS 39D. Two (a JAS 39C and a JAS 39D) were lost in accidents.
  • Thailand – 12 Gripens (8 JAS 39C and 4 JAS 39D) serve with the Thai Air Force, where eventually 6 more Gripen would be bought. As these Gripen operate over the Andaman Sea and Gulf of Thailand, they have anti-ship capacities.
  • United Kingdom – Operated by the Empire Test Pilots’ School, with 3 JAS 39B, with training and testing purposes.

Gripen Specifications

Wingspan  8.4 m / 27 ft 7 in
Length  14.10 m / 46 ft 3 in
Height  4.7 m / 14 ft 9 in
Wing Area 30 m² / 323 ft²
Engine 1 Volvo Flygmotor turbofan RM12
Maximum Take-Off Weight 14000 Kg / 30,900 lb
Empty Weight 6800 kg / 15,000 lb
Loaded Weight 8500 kg / 18,700 lb
Maximum Speed 2450 km/h / 1522 mph
Range 3250 KM / 1,983 miles (with external drop fuel tanks)
Maximum Service Ceiling 16000 m /52,500 ft
Climb Rate 100 s from brake release to 10 km altitude / 180 s approx to 14 km
Crew 1 or 2
Armament • 1 Mauser BK 27 27mm cannon
• 6 hardpoints that could allow 6 air-to-air missiles, 4 air-to-radar missiles, 4 air-to-surface missiles, 5 smart bombs, 2 anti-ship missiles, 5 bombs, 2 stand-off weapons, 2 ECM Pods, 2 recce Pods, 1 FLIR/LDP Pod, 2 AACMI Pods, and 3 fuel tanks

Gallery

J39C Gripen of the Flygvapnet – Swedish Air Force armed with wingtip IRIS-T Missiles
J39C Gripen of the South African Air Force equipped with a wing drop tank and IRIS-T missiles

Sources

Berger, R (Ed.). Aviones [Flugzeuge, Vicenç Prat, trans.]. Colonia, Alemania: Naumann & Göbel Verlagsgessellschaft mbH. , Hellenius, B (March 2014). Griffin Takes Wing. Air Forces Monthly, (312), 50-65. , SAAB (March 2016). Gripen brochure. , SAAB (n.d.). Gripen-Advanced Weapons Flexibility. , SAAB (n.d.). Gripen dimensions. , Singh, V (May-June 2014). The Gripen forges ahead – in ‘Super’ mode. VAYU Aerospace & Defence Review, (3) 61-65.  , Sharpe, M (2001). Jets de Ataque y Defensa [Attack and Interceptor Jets, Macarena Rojo, trans.]. Madrid, Spain: Editorial LIBSA (Original work published in 2001). , Wikipedia:Saab JAS 39 Gripen Images: SAAB Gripen Taxiing by Airwolfhound / CC BY-SA 2.0 ,  SAAB Gripen Parked by Milan Nykodym / CC BY-SA 2.0 , SAAB Gripen Armed in Flight by AereiMilitari.org / CC BY-NC 2.0