The Saab 37 Viggen ("Thunderbolt", ambiguous with ?"Tufted duck") is a Swedish single-seat, single-engine, short-medium range combat aircraft. Development work on the type was initiated at Saab in 1952 and, following the selection of a radical delta wingconfiguration, the resulting aircraft performed its first flight one 8 February 1967 and entered service in 21 June 1971. The Viggen holds the distinction of being the first canard design to be produced in quantity.Several distinctive variants of the Viggen were produced to perform the roles of strike fighter (AJ37), aerial reconnaissance (SF 37), maritime patrol aircraft (SH 37) and a two-seat trainer(SK 37). In the late 1970s, the all-weather fighter-interceptor aircraft JA 37 variant was introduced. In November 2005, the Viggen was retired from service by the Swedish Air Force, the sole operator of the type, having been replaced by the newer Saab JAS 39 Gripen.