The first of four flight prototypes of the "J 21R" -- the "R" stood for "reaction jet" -- performed its initial flight on 10 March 1947, with Aeke Sunden at the controls. All the prototypes were conversions of J 21s. Initial production deliveries were in the summer of 1949, with a total of 64 J 21Rs delivered. The first 34 featured the RM 1 / Goblin 1 engine with 13.1 kN (1,335 kgp / 2,945 lbf) thrust and were designated "J 21RA", while the final 30 were fitted with the RM 1A / Goblin 3 with 14.7 kN (1,500 kgp / 3,305 lbf) thrust and were designated "J 21RB".
Fighter design was moving at a rapid pace at the time and the J 21 was obsolete from the start, being quickly relegated to the attack role as the "A 21R", carrying up to ten 15 centimeter (5.9 inch) or 18 centimeter (7.1 inch) unguided rockets. It could also carry a centerline gun pod with eight 8 millimeter machine guns for strafing, with pilots finding the experience of firing all 13 guns at once to be "exciting". Handling was as good as that of the J 21, but performance was not competitive with other jet fighters of the era, and fell off badly at altitude. Endurance was poor, though the wingtip tanks of the A 21 could be fitted to improve matters. However, even as the J 21R was being put into service, SAAB was working on a much more advanced jet fighter, the "J 29 Tunnan", that would be a match for foreign jet fighters of its era. The J 21R, like many very early combat jets elsewhere, was mostly a learning experience for Swedish industry and the Flygvapnet. All J 21Rs were retired by the mid-1950s. Only one survives today.
3D model, pivots, UV map , CS: Willsonman
Physics: Willsonman with some help from DHK
Standard control setup with brakes on the 3-position switch. All the way toward you is off.
Development thread: https://forums.realflight.com/showthread.php?t=21175
Fighter design was moving at a rapid pace at the time and the J 21 was obsolete from the start, being quickly relegated to the attack role as the "A 21R", carrying up to ten 15 centimeter (5.9 inch) or 18 centimeter (7.1 inch) unguided rockets. It could also carry a centerline gun pod with eight 8 millimeter machine guns for strafing, with pilots finding the experience of firing all 13 guns at once to be "exciting". Handling was as good as that of the J 21, but performance was not competitive with other jet fighters of the era, and fell off badly at altitude. Endurance was poor, though the wingtip tanks of the A 21 could be fitted to improve matters. However, even as the J 21R was being put into service, SAAB was working on a much more advanced jet fighter, the "J 29 Tunnan", that would be a match for foreign jet fighters of its era. The J 21R, like many very early combat jets elsewhere, was mostly a learning experience for Swedish industry and the Flygvapnet. All J 21Rs were retired by the mid-1950s. Only one survives today.
3D model, pivots, UV map , CS: Willsonman
Physics: Willsonman with some help from DHK
Standard control setup with brakes on the 3-position switch. All the way toward you is off.
Development thread: https://forums.realflight.com/showthread.php?t=21175
