Saab AJ37 Viggen
Due to Sweden’s proximity to the Soviet Union, the Swedish Air Force had to assume that their fixed airfields would be destroyed in the opening hours of a war with the USSR. With that in mind, Saab was tasked with designing an aircraft that could operate away from airfields, yet still be able to reach Mach 2 at altitude and replace both the J32 Lansen in the ground attack role and the J35 Draken as an interceptor. It was a daunting task to say the least.
Because the aircraft would need high performance as well as short takeoff or landing (STOL) capability, Saab chose for what was, at the time, a radical design: the combination of a delta wing and high-mounted canards. This was to both provide better turning performance for a delta winged design, plus give lift for a short takeoff run and drag for landings. To further lower landing speed, Saab chose another ahead-of-its-time idea for the aircraft’s propulsion, using a license-built JT8D turbofan; the JT8D had to that point been an airliner engine, but it had a thrust reverser. By adding an afterburner, it would still retain the performance of contemporary fighters, although at a severe cost in range. This was not seen as a disadvantage, as the aircraft was meant to be fighting over Swedish territory in any case. Finally, Saab was to produce an aircraft that was robust in design and easy to maintain—an important consideration when it was operating away from airfields and being repaired by conscripts. Saab’s design fufilled all the requirements asked of it and was designated the AJ37 Viggen (Thunderbolt). The first AJ37 flew in December 1967 and entered service in 1972.
Though the first variant, the AJ37, was intended primarily for ground support and antishipping strikes, it was always intended for the Viggen to have growth potential. First was a two-seat conversion trainer, the SK37, which had originally not been planned, but there was more difference in flying characteristics between the “pure delta” J35 Draken and the Viggen than the Swedish Air Force had planned. The radar and one centerline fuel tank was eliminated in place of a second cockpit stepped above and apart from the first. Next was the SH37 dedicated antishipping variant, which differed from the AJ37 only in having a different radar and a long-range camera; the SF37 reconnaissance variant, with a longer “chisel” nose, no radar, and six cameras in the nose debuted in 1974.
Finally, as the J35 Draken interceptor fleet began to show its age, the JA37 interceptor came out in 1980, with a redesigned cockpit optimized for the fighter role, uprated engine, more advanced multimode radar, an internal cannon (the heavy Oerlikon KCA 30mm cannon, the heaviest installed in any European fighter), and capability to fire the Skyflash missile, a British-improved AIM-7 Sparrow. All five variants performed well and was well-liked by their pilots. JA37 pilots complained of poor vision to the rear, but the zoom climb characteristics and superb radar of the Viggen allowed them to even intercept and track USAF SR-71 Blackbirds coming out of Russian airspace. Saab attempted to market the Viggen internationally, building on the modest success of the Draken, but despite some interest from India and Japan, no buyers were found.
The Viggen was to be the primary aircraft operated by the Svenska Flygvapnet throughout the late 1970s through the 1980s and 1990s, replacing the Lansen and Draken as planned. It was continually updated throughout its lifetime, and delays to the Viggen’s replacement, the JAS39 Gripen, resulted in a comphrensive update in the mid-1990s. This was mainly an avionics update that allowed the Viggen to carry the AIM-120 AMRAAM, but also combined some of the aspects of the five variants into one airframe. These were redesignated AJSF37, and would serve until the dawn of the 21st Century. The Viggen was finally retired in 2007 in favor of the multirole fourth-generation Gripen, ending over 35 years of service in which it never fired a shot in anger.
This aircraft belongs to the 7th Fighter Wing at Satenas, Sweden, and is painted in an experimental white over light blue camouflage; this scheme was not kept, and JA37s usually carried a complicated three shades of green over gray splinter scheme.
Saab AJ37 Viggen
Due to Sweden’s proximity to the Soviet Union, the Swedish Air Force had to assume that their fixed airfields would be destroyed in the opening hours of a war with the USSR. With that in mind, Saab was tasked with designing an aircraft that could operate away from airfields, yet still be able to reach Mach 2 at altitude and replace both the J32 Lansen in the ground attack role and the J35 Draken as an interceptor. It was a daunting task to say the least.
Because the aircraft would need high performance as well as short takeoff or landing (STOL) capability, Saab chose for what was, at the time, a radical design: the combination of a delta wing and high-mounted canards. This was to both provide better turning performance for a delta winged design, plus give lift for a short takeoff run and drag for landings. To further lower landing speed, Saab chose another ahead-of-its-time idea for the aircraft’s propulsion, using a license-built JT8D turbofan; the JT8D had to that point been an airliner engine, but it had a thrust reverser. By adding an afterburner, it would still retain the performance of contemporary fighters, although at a severe cost in range. This was not seen as a disadvantage, as the aircraft was meant to be fighting over Swedish territory in any case. Finally, Saab was to produce an aircraft that was robust in design and easy to maintain—an important consideration when it was operating away from airfields and being repaired by conscripts. Saab’s design fufilled all the requirements asked of it and was designated the AJ37 Viggen (Thunderbolt). The first AJ37 flew in December 1967 and entered service in 1972.
Though the first variant, the AJ37, was intended primarily for ground support and antishipping strikes, it was always intended for the Viggen to have growth potential. First was a two-seat conversion trainer, the SK37, which had originally not been planned, but there was more difference in flying characteristics between the “pure delta” J35 Draken and the Viggen than the Swedish Air Force had planned. The radar and one centerline fuel tank was eliminated in place of a second cockpit stepped above and apart from the first. Next was the SH37 dedicated antishipping variant, which differed from the AJ37 only in having a different radar and a long-range camera; the SF37 reconnaissance variant, with a longer “chisel” nose, no radar, and six cameras in the nose debuted in 1974.
Finally, as the J35 Draken interceptor fleet began to show its age, the JA37 interceptor came out in 1980, with a redesigned cockpit optimized for the fighter role, uprated engine, more advanced multimode radar, an internal cannon (the heavy Oerlikon KCA 30mm cannon, the heaviest installed in any European fighter), and capability to fire the Skyflash missile, a British-improved AIM-7 Sparrow. All five variants performed well and was well-liked by their pilots. JA37 pilots complained of poor vision to the rear, but the zoom climb characteristics and superb radar of the Viggen allowed them to even intercept and track USAF SR-71 Blackbirds coming out of Russian airspace. Saab attempted to market the Viggen internationally, building on the modest success of the Draken, but despite some interest from India and Japan, no buyers were found.
The Viggen was to be the primary aircraft operated by the Svenska Flygvapnet throughout the late 1970s through the 1980s and 1990s, replacing the Lansen and Draken as planned. It was continually updated throughout its lifetime, and delays to the Viggen’s replacement, the JAS39 Gripen, resulted in a comphrensive update in the mid-1990s. This was mainly an avionics update that allowed the Viggen to carry the AIM-120 AMRAAM, but also combined some of the aspects of the five variants into one airframe. These were redesignated AJSF37, and would serve until the dawn of the 21st Century. The Viggen was finally retired in 2007 in favor of the multirole fourth-generation Gripen, ending over 35 years of service in which it never fired a shot in anger.
This aircraft belongs to the 7th Fighter Wing at Satenas, Sweden, and is painted in an experimental white over light blue camouflage; this scheme was not kept, and JA37s usually carried a complicated three shades of green over gray splinter scheme.