Saab 21R

SAAB 21R
Saab 21R in Linköping museum
Role	Fighter and attack aircraft
Manufacturer	SAAB
Designer	Frid Wänström
First flight	10 March 1947
Introduction	1950
Retired	1956
Status	retired
Primary user	Swedish Air Force
Produced	1950-1952
Number built	64
Developed from	Saab 21

The Saab 21R was a Swedish twin-boom fighter/attack aircraft made by SAAB. It was a jet-powered development of the piston-engined Saab 21 and is unusual for being the only airframe that saw service as both a piston-engined fighter, and a jet fighter. As a fighter, its service designation in the Swedish Air Force was J 21R, and saw service in the late 1940s.

Design and development

The 21R was powered by a de Havilland Goblin 3 turbojet (RM 1) and was Sweden's first jet-powered aircraft to be developed and built domestically.

There were quite a few differences between the 21A and the 21R, aside from the method of propulsion. The most notable difference was that the tailplane was raised to the top of the fins, moving it out of the way of the jet blast.

Operational history

The first prototype Saab 21R first flew on 10 March 1947, just after the Second World War. The aircraft first entered into service with F 10 in August 1950. Although the type was originally intended as a fighter aircraft, a newly developed fighter, the Saab J 29 first flew in October 1948, the number to be produced was halved from 120 to 60, and eventually all 21Rs were converted to attack aircraft as A 21RA or the A 21RB depending on the engine type.

Variants

J 21RA / A 21RA

First production series, powered by British-built engines, 34 built in 1950 (including four prototypes), retired in 1953.

J 21RB / A 21RB

Second production series, powered by Swedish-built engines, 30 built between 1950 and 1952, retired in 1956.

Operators

Sweden

• Swedish Air Force

Specifications (Saab 21RA)

Data from Attack and Interceptor Jets

General characteristics

• Crew: One
• Length: 10.45 m (34 ft 3 in)
• Wingspan: 11.37 m (37 ft 4 in)
• Height: 2.90 m (9 ft 8 in)
• Empty weight: 3,200 kg (7,055 lb)
• Max. takeoff weight: 5,000 kg (11,023 lb)
• Powerplant: 1 × de Havilland Goblin 2 turbojet, 13.8 kN (3,100 lbf)

Performance

• Maximum speed: 800 km/h (497 mph)
• Range: 720 km (450 mi)
• Service ceiling: 12,000 m (39,400 ft)
  

• Takeoff roll: 650 m (2,133 ft)

Armament

• 1x 20 mm Bofors Cannon
• 4x 13.2 mm M/39A Heavy machine guns
• Centerline pod for an additional 8x 13.2 mm M/39A Heavy machine guns
• Wing racks for either: 10x 100 mm or 5x 180 mm Bofors rockets, or 10x 80 mm anti-tank rockets.

See also

Related development

• Saab 21
  

Aircraft of comparable role, configuration and era

• Kyushu J7W
• Curtiss XP-55 Ascender
• de Havilland Vampire
• Saab 21
  

Related lists

• List of fighter aircraft
• List of military aircraft of Sweden
  

References

Notes

Bibliography

• Andersson, Hans G. Saab Aircraft since 1937 (1st ed.). London: Putnam, 1989. ISBN 0-85177-831-3.
• Billing, Peter. "SAAB's Jet Debutant". Air Enthusiast, Twenty-three, December 1983-March 1984. Bromley, UK:Fine Scroll. ISSN 0143-5450. pp. 20–30.
• Sharpe, Michael. Attack and Interceptor Jets. London: Friedman/Fairfax Publishers, 1999. ISBN 1-58663-301-5.
• Widfeldt, Bo. The Saab 21 A & R (Aircraft in Profile number 138). Leatherhead, Surrey, UK: Profile Publications Ltd., 1966.

External links

• SAAB 21 story
• J.21R in the Air - a 1948 Flight article on flying the SAAB J.21R