Saab 21R

Saab 21R
General information
Type	Fighter and attack aircraft
National origin	Sweden
Manufacturer	SAAB
Status	Retired
Primary user	Swedish Air Force
Number built	64
History
Manufactured	1950–1952
Introduction date	1950
First flight	10 March 1947
Retired	1956
Developed from	SAAB 21

The Saab 21R was a Swedish fighter/attack aircraft developed and produced by Svenska Aeroplan AB (SAAB). It was a jet-powered development of the piston-engined SAAB 21 and was the first jet aircraft to be produced by Saab. The R-suffix stands for reaktion (reaction), referencing reaktionsdrift (jet power) or reaktionsmotor (jet engine). Along with the Soviet Yakovlev Yak-15, the 21R was one of only two jet fighters to have been successfully converted from piston-powered aircraft.^[1]

Sweden was under threat during the Second World War, and ordered SAAB to develop an advanced fighter. The result was an unorthodox twin-boom pusher, with a low wing, tricycle landing gear, and a heavy forward-firing armament. Several options were then explored to improve its performance, leading to a jet-powered version.

During 1947, SAAB began converting the piston-engined J 21s to jet propulsion, which required extensive modifications. One hundred twenty-four aircraft were planned, however this number was reduced to 64 and they were instead mainly used as fighter-bombers. It saw service in the late 1940s and early 1950s before it was replaced by a new generation of fighters designed from the onset with jet propulsion, such as the de Havilland Vampire and the Saab 29 Tunnan.