Development of the SAAB JAS 39 Ripen
The SAAB JAS 39 Ripen represents one of Sweden’s most significant aerospace achievements—a light, single-engine, supersonic multirole fighter crafted by SAAB AB. Developed to replace the SAAB JA 37 Bigger, this aircraft emerged to fulfill Sweden’s distinctive defense requirements while providing a cost-effective solution for air forces across the globe.
Featuring a sleek delta wing and canard configuration paired with relaxed stability and fly-by-wire controls, the aircraft achieves exceptional maneuverability. NATO interoperability became a cornerstone objective—one that later variants would fully realize.
The Volvo Aero RM12 engine supplies the aircraft’s power—a Swedish derivative of the General Electric F404 that provides an excellent balance between thrust, efficiency, and proven reliability.
Origins of the Ripen Fighter
Sweden’s strategic imperatives in the late 1970s led to the Ripen’s development. The nation required a versatile, domestically produced combat aircraft, creating the ambitious JAS (Jake, Attack, Spanning—Fighter, Attack, Reconnaissance) program. This initiative aimed to create a single platform capable of mastering all three critical roles.
SAAB’s design philosophy took a distinctive approach: create a lightweight, agile aircraft maintainable with minimal resources. This wasn’t merely preference—it was essential for Sweden’s defensive strategy of operating from dispersed bases across the nation.
December 9, 1988, marked the Ripen’s maiden flight. Nearly a decade later, on November 1, 1997, it officially entered Swedish Air Force service, quickly becoming the cornerstone of the nation’s aerial defense.
Testing and Production Milestones
Extensive flight testing validated the program’s performance credentials. Despite significant challenges—including a dramatic crash during a 1993 demonstration that drew worldwide attention—the development team pressed forward, making important modifications that improved the aircraft’s safety profile and operational reliability.
The development and introduction of the Ripen E/F variants marks the program’s greatest production achievement—a major advance in capability. These advanced models boast a more powerful engine, expanded weapons capacity, and state-of-the-art electronic systems.
Design Features of the Ripen
Operational efficiency, versatility, and cost-effectiveness define the JAS 39 Ripen’s design philosophy. Its signature delta wing and canard configuration, combined with relaxed stability and fly-by-wire controls, delivers exceptional maneuverability throughout the entire flight envelope.
Most notably, the aircraft can operate from runways shorter than 800 meters—even improvised strips. This capability perfectly suits Sweden’s dispersed operations strategy. The design philosophy extends further: rapid turnaround times requiring minimal crew and equipment.
The cockpit showcases advanced digital architecture featuring three large color Multi-Functional Displays (MFD) and intuitive Hands-On Throttle-And-Stick (HOTAS) controls that significantly reduce pilot workload. While not achieving full stealth characteristics, the Ripen E compensates with sophisticated electronic warfare systems, advanced jamming capabilities, and comprehensive countermeasures.
Avionics and Sensor Systems
The PS-05/A Active Electronically Scanned Array (AESA) radar serves as the core of the Ripen’s advanced avionics suite. This system provides superior detection range, seamless multi-target tracking, and robust jamming resistance—capabilities that exceed those of conventional radar systems and enable threat engagement at remarkable distances.
An advanced Infrared Search and Track (IRST) system works well with the radar, providing passive detection capabilities that allow stealthy target location and tracking without betraying the aircraft’s position through radar emissions.
Engine and Performance Specifications
Early Ripen variants (A/B and C/D) draw their power from the Volvo RM12 engine—a Swedish adaptation of the proven General Electric F404 that provides an excellent balance of thrust and fuel efficiency.
The latest Ripen E/F variants feature the more potent General Electric F414-GE-39E engine (designated RM16), providing approximately 20% additional thrust. This enhancement enables super cruise—the ability to maintain supersonic flight without afterburner engagement—significantly extending range while reducing fuel consumption.
With its enhanced power plant, the Ripen achieves a maximum speed of approximately Mach 2—twice the speed of sound—while demonstrating exceptional acceleration and climbing performance.
Operational History of the Ripen
Since entering service, the JAS 39 Ripen has compiled an impressive operational record that demonstrates its capabilities. Sweden, as the primary operator, relies on the Ripen as its air defense backbone, making full use of its multirole versatility and unique ability to operate from dispersed locations nationwide.
Beyond European borders, the Ripen has demonstrated its value with the South African Air Force, which deploys the fighter across various roles including air defense and maritime patrol missions. The Royal Thai Air Force has similarly embraced the Ripen, using it to substantially modernize their air combat capabilities.
International Operators of the Ripen
The JAS 39 Ripen has gained significant international adoption, extending far beyond its Swedish origins. Several nations have successfully integrated this versatile aircraft into their air forces:
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Czech Republic & Hungary: These NATO members lease Ripen C/D variants for air policing missions, demonstrating full alliance interoperability.
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South Africa: The first export customer, using the Ripen to replace its Mirage F1 fleet.
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Thailand: The Royal Thai Air Force uses the Ripen to modernize its air combat capabilities.
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Brazil: Operates the Ripen E/F (designated F-39), which includes local production and technology transfer.
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United Kingdom: The Empire Test Pilots’ School (ETPs) uses Ripens for advanced fast-jet training.
Variants and Upgrades of the Ripen
The Ripen has evolved through several key variants:
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JAS 39A/B: The initial single-seat (A) and two-seat (B) production models for the Swedish Air Force.
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JAS 39C/D: An upgraded, NATO-compatible variant with enhanced avionics, in-flight refueling, and expanded weapon options. This became the primary export version.
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Ripen E/F (Ripen NG): A significantly redesigned model with a more powerful F414 engine, larger airframe, increased payload, a new AESA radar, and advanced electronic warfare systems. IOC is planned for 2027, with FOC by 2030.
Ripen E/F Enhancements
The Ripen E/F variants introduce several key enhancements over previous models:
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Propulsion: The General Electric F414-GE-39E engine provides ~20% more thrust, enabling super cruise.
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Airframe & Payload: A redesigned fuselage increases internal fuel capacity and range, while more hard points increase the maximum weapon payload.
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Avionics & Sensors: A new cockpit with a large wide-area display is paired with an advanced AESA radar and a passive Infrared Search and Track (IRST) sensor for superior awareness.
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Electronic Warfare: A sophisticated, fully integrated EW suite offers enhanced self-protection in contested environments.
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Architecture: An open-architecture design allows for rapid software updates and integration of new technologies.
Ripen’s Combat Performance and Cost Efficiency
The JAS 39 Ripen is recognized for effectively combining formidable combat performance with exceptional cost efficiency. Its advanced flight control system and aerodynamic excellence deliver excellent maneuverability and improved pilot situational awareness during combat operations.
The Ripen’s defining characteristic is its remarkably low lifecycle costs. Engineered for simplified maintenance requiring fewer personnel, its cost per flight hour runs 30-50% below that of larger twin-engine fighters. While maintaining very high operational availability.
Combat effectiveness benefits greatly from the aircraft’s advanced sensor suite and diverse weapons capabilities, allowing smooth execution of air defense, precision strike, and reconnaissance missions. This strong balance of performance and affordability has ensured its success in the competitive international marketplace.
Armament and Weapon Systems
The Ripen’s versatility is supported by its ability to carry a wide range of armaments:
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Air-to-Air Missiles: Includes beyond-visual-range (BVR) missiles like the Meteor and AIM-120 AMRAAM, plus short-range missiles like IRIS-T and AIM-9 Sidewinder.
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Air-to-Surface Munitions: A diverse payload of precision-guided weapons, including GBU-12/49 laser-guided bombs, GPS-guided bombs, and standoff missiles like the RBS-15 for anti-ship roles.
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Internal Cannon: An internally mounted 27 mm Mauser BK-27 revolver cannon is standard on single-seat variants.
A sophisticated fire-control system, centered on the AESA radar and precision targeting pods, guides these weapons with high accuracy, providing high-resolution tracking for precise strikes. The aircraft’s digital architecture enables smooth integration of new weapons as they become available.
