Aircraft was a J 21A-2 equipped with a bomb aiming sight and had pylons for bombs and rockets. It was later upgraded to be able to use two RATO rockets. J 21B Planned version armed with three nose guns, radar in the starboard boom, improved aerodynamics, P-51 style bubble canopy and a stronger engine. Suggested engines were at first the Daimler-Benz DB 605E or the Rolls-Royce Griffon engine but due to the end of the war Germany could not deliver the DB-605E and the British had not yet finished the development of the Griffon engine. It was then decided to use the Swedish DB-605B engine modified to 1700 hp. A full scale mockup was built but due to the jet age the project was scrapped at the end of 1945 due to the Saab 29 project. None built. Operators Swedish Air Force Survivors Three aircraft are preserved on permanent static display; J 21A-3, serial 21286, but rebuilt as an A 21R, at the Swedish Air Force Museum. J 21A-3, serial 21311 at F 15 Söderhamn Flygmuseum. J 21A-3, serial 21364 at the Swedish Air Force Museum. Specifications (J 21A) {{Aircraft specs |ref=Beskrivning över fpl typ 21A, häfte 1 (description of airplane type 21A, booklet 1), Beskrivning över fpl typ 21A, häfte 6 kap L. Beväpning (description of airplane type 21A, booklet 6, chapter L. armament), SAAB J21/J21R |prime units?=met |crew=1 |length m=10.45 |length note= |span m=11.6 |span note= |height m=3.97 |height note= |wing area sqm=22.2 |wing area note= |aspect ratio= |airfoil=Saab laminar airfoil |empty weight kg=3250 |empty weight note= |gross weight kg=4150 |gross weight note= |max takeoff weight kg=5200 |max takeoff weight note= |fuel capacity= internal 2x drop tanks (J 21A-1 & J 21A-2) ; 2x drop tanks (J(A) 21A-3) |more general= |eng1 number=1 |eng1 name=Daimler-Benz DB 605B |eng1 type=V-12 inverted liquid-cooled piston engine |eng1 kw=1085 |eng1 note=built by SFA |prop blade number=3 |prop name=constant-speed pusher propeller |prop dia m= |prop dia note= |max speed kmh=650 |max speed note=J 21A-1 / J 21A-2 J(A) 21A-3 |cruise speed kmh=495 |cruise speed note=J 21A-1 / J 21A-2 J(A) 21A-3 |stall speed kmh= |stall speed note= |never exceed speed kmh= |never exceed speed note= |range km=750 |range note= |combat range km= |combat range note= |ferry range km=1190 |ferry range note=J 21A-1 / J 21A-2 J(A) 21A-3 |endurance= |ceiling m=10200 |ceiling note=J 21A-1 / J 21A-2 J(A) 21A-3 |climb rate ms=15 |climb rate note=