The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft propulsion.
 The word "turbofan" is a portmanteau of "turbine" and "fan": the "turbo" portion refers to a gas turbine engine which achieves mechanical energy from combustion, and the "fan", a ducted fan that uses the mechanical energy from the gas turbine to accelerate air rearwards.
 Thus, whereas all the air taken in by a turbojet passes through the turbine (through the combustion chamber), in a turbofan some of that air bypasses the turbine.
 A turbofan thus can be thought of as a turbojet being used to drive a ducted fan, with both of those contributing to the thrust.
 The ratio of the mass-flow of air bypassing the engine core compared to the mass-flow of air passing through the core is referred to as the bypass ratio.
 The engine produces thrust through a combination of these two portions working together; engines that use more jet thrust relative to fan thrust are known as "low-bypass turbofans", conversely those that have considerably more fan thrust than jet thrust are known as "high-bypass".
 Most commercial aviation jet engines in use today are of the high-bypass type, and most modern military fighter engines are low-bypass.
 Afterburners are not used on high-bypass turbofan engines but may be used on either low-bypass turbofan or turbojet engines.
The Volvo RM8 is a low-bypass afterburning turbofan jet engine developed for the Saab 37 Viggen fighter.
 In 1962, the Pratt & Whitney JT8D-1 engine was chosen to power the Viggen in absence of a suitable and available engine designed for military use.
 Basically a licensed-built version of the JT8D, heavily modified for supersonic speeds, with a Swedish-designed afterburner, the RM8 was produced by Svenska Flygmotor (later known as Volvo Aero).
The Saab JAS 39 Gripen (English: "griffin" ) is a light single-engine multirole fighter aircraft manufactured by the Swedish aerospace company Saab.
 It was designed to replace the Saab 35 Draken and 37 Viggen in the Swedish Air Force ("Flygvapnet").
 The Gripen has a delta wing and canard configuration with relaxed stability design and fly-by-wire flight controls.
 It is powered by the Volvo RM12, and has a top speed of Mach 2.
 Later aircraft are modified for NATO interoperability standards and to undertake in-flight refuelling.
The Saab 38 (also known as B3LA or A 38/Sk 38) was a single-engine jet trainer and attack aircraft planned by Saab during the 1970s.
 The project was a collaboration between Saab and the Italian aircraft manufacturer Aermacchi.
 It was to replace the older Saab 105 jet trainer in the Swedish Air Force, but the aircraft never got past the drawing board and was canceled in 1979 in favour of the more advanced Saab JAS 39 Gripen fighter.
The Klimov RD-33 is a turbofan jet engine for a lightweight fighter jet that is the primary engine for the Mikoyan MiG-29 and CAC/PAC JF-17 Thunder.
 It was developed in OKB-117 led by S. P. Izotov (now OAO Klimov) from 1968 with production starting in 1981.
 Previous generations of Russian supersonic fighters such as the MiG-21 and MiG-27 used turbojets, but western fighters such as the F-111 and F-4K introduced the use of afterburning turbofans in the 1960s which were more efficient.
 The RD-33 was the first afterburning turbofan engine produced by the Klimov company of Russia in the 8000 to thrust class.
 It features a modular twin-shaft design with individual parts that can be replaced separately and has a good tolerance to the environment.
 The RD-33 is simple to maintain and retains good performance in challenging environments.
Industrigruppen JAS (IG JAS) was a Swedish industrial consortium under executive director Harald Schröder founded in August 1980 by Saab-Scania (later Saab), Volvo Flygmotor, LM Ericsson, Svenska Radioaktiebolaget Communications and Förenade Fabriksverken (FFV) for the development, construction and manufacturing of the new Swedish combat aircraft JAS 39 Gripen on behalf of the Swedish Airforce.
The tender was submitted in June 1981 to Försvarets Materielverk (FMV), and on 30 June 1982 a contract was signed for development, and for five prototype aircraft and 30 production aircraft.
Bombkapsel 90 (BK90) is the Swedish Air Force's nomenclature for a gliding stand-off submunitions dispenser, or cluster bomb, with 72 submunitions.
 It is manufactured by DaimlerChrysler Aerospace in Germany by the name of DWS 24 - "Dispenser Weapon System 24 barrels".
 The BK90 is also commonly known as DWS 39 "Mjölner" because it was intended for use with the Saab JAS 39 Gripen.
 In the future it could be also integrated on the Eurofighter Typhoon.
 Its design is very similar to that of the American AGM-154 Joint Standoff Weapon.
Link-ZA (also "Link ZA" or "LinkZA") is a tactical data link system used by the South African National Defence Force.
 It is the data communication component of the "Combat Net Interoperability Standard" (CNIS).
 Development began in the early 1990s when South Africa acquired a wide variety of high technology defence equipment such as Saab JAS 39 Gripen fighter jets, BAE Hawk lead-in fighter trainers, Valour-class frigates and other weapons systems.
 Because South Africa was not able to acquire the NATO standard Link-16 system an indigenous system was developed.
The Volvo RM12 is a low-bypass afterburning turbofan jet engine developed for the Saab JAS 39 Gripen fighter.
 A version of the General Electric F404, the RM12 was produced by Volvo Aero (now GKN Aerospace Engine Systems).
The V3E A-Darter (Agile Darter) is a modern short-range infrared homing ("heat seeking") air-to-air missile, featuring countermeasures resistance with a 180-degree look angle and 120-degrees per second track rate, developed by South Africa's Denel Dynamics (formerly Kentron) and Brazil's Mectron, Avibras and Opto Eletrônica.
 It will equip South African Air Force's Saab JAS 39 Gripen C/D and BAe Hawk 120; Brazilian Air Force's A-1M AMX, Northrop F-5BR and Gripen E/F.
 It is expected to be in production before the end of 2015.

Question: Which low-bypass afterburning turbofan jet engine is used to power the Saab JAS 39 Gripen? 
Answer: Volvo RM12