In the aftermath of the Second World War, it was decided that Sweden needed a strong air defence built around the newly developed jet propulsion technology. Project "JxR" began in the final months of 1945 with two proposals from the Saab design team led by Lars Brising. The first, codenamed R101, was a cigar-shaped aircraft somewhat similar to the American Lockheed P-80 Shooting Star. The winning design however was the "barrel" design, codenamed R 1001, which proved to be both faster and more agile.
Saab 29 Tunnan oli ensimmäinen ruotsalainen suihkuhävittäjä. Konetta on kutsuttu sen rungon muodon mukaan "tynnyriksi" tai "lentäväksi tynnyriksi".
Toisen maailmansodan loputtua Ruotsin ilmavoimat hankki englantilaisia De Havilland Vampire -hävittäjäkoneita. Saab käynnisti oman tutkimuksen suihkuhävittäjästä.
Ruotsi sai Sveitsin kautta saksalaisten sodan aikaista aerodynaamista tietotaitoa, jonka avulla se lähti suunnittelemaan nuolisiipistä konetta. Tietotaitoa toivat myös Saksasta palaavat ruotsalaiset insinöörit ja Saksasta Ruotsiin tulleet saksalaiset insinöörit.
Esimerkiksi Yhdysvallat suunnitteli pääasiassa suorasiipisiä koneita, koska saksalaisen Alexander Lippischin suunnittelemaa 45° deltasiipeä pidettiin siellä vielä tuolloin liian erikoisena.
Venäläiset ottivat nuolisiiven nopeasti käyttöön suihkukoneissaan.
Tunnanista tehtiin neljä prototyyppiä. Koneen ensilento tapahtui 1. syyskuuta 1948.
Koneita valmistettiin 1951–1956 kaikkiaan 661 kappaletta:
224 kpl versiota J 29A (hävittäjä)
361 kpl J/A 29B -versiota (hävittäjäpommittaja)
76 kpl S 29C-versiota (tiedustelu)
30 Tunnania myytiin Itävaltaan 1960-luvun alussa.
Ruotsin ilmavoimat käyttivät Tunnania vuoteen 1976 asti.
Tunnania käytettiin YK:n palveluksessa Kongon kriisin aikana 1961–1963 sotatoimissa.
The original R 1001 was designed around a mostly straight wing, but after the Swedish engineers had obtained German research data on swept-wing designs, the prototype was altered to incorporate a 25 degree sweep, first tested on a modified Saab Safir (designated Saab 201).
A member of the Saab engineering team had been allowed to review German aeronautical documents stored in Switzerland. These files captured by the Americans in 1945 clearly indicated delta and swept-wing designs had the effect of "reducing drag dramatically as the aircraft approached the sound barrier."
Length: 10.23 m (33 ft 7 in)
Wingspan: 11.0 m (36 ft 1 in)
Height: 3.75 m (12 ft 4 in)
Wing area: 24.15 m² (260.0 ft²)
Empty weight: 4,845 kg (10,680 lb)
Max. takeoff weight: 8,375 kg (18,465 lb)
Powerplant: 1 × Svenska Flygmotor RM 2B turbojet, 6,070 lbf (27 kN)
Maximum speed: 1,060 km/h (660 mph)
Range: 1,100 km (685 mi)
Service ceiling: 15,500 m (50,850 ft)
Rate of climb: 32.1 m/s (6,320 ft/min)
Armament: 4x20mm Hispano Mark V autocannon
75 mm (3 in) air-to-air rockets
Rb 24 air-to-air missiles
145 mm (5.8 in) anti-armor rockets, 150 mm (6 in) HE (high-explosive) rockets, 180 mm (7.2 in) HE antiship rockets
The SAAB 29 prototype flew for the first time on 1 September 1948. It was a small, chubby aircraft with a single central air intake, a bubble cockpit and a very thin swept-back wing. The test pilot was an Englishman, S/L Robert A. 'Bob' Moore, DFC and bar, who went on to become the first managing director of Saab GB Ltd, UK, set up in 1960.
Moore described the aircraft as "on the ground an ugly duckling – in the air, a swift." Because of its shape, The Saab J 29 was quickly nicknamed "Flygande Tunnan" ("The Flying Barrel") or "Tunnan" ("The Barrel") for short. While the demeaning nickname was not appreciated by SAAB, its shortform was officially adopted. Since then, Saab named the aircraft in order to avoid it happening again. A total of 661 Tunnans were built from 1950 to 1956, making it the largest production run for any Saab aircraft.
The J 29 was one of the first production fighters with a swept-back wing. It was fast and agile, and set the world speed record on a 500 km (310 mi) closed circuit in 1954 at 977 km/h (607.05 mph). Two S 29C (reconnaissance variant) additionally set an international speed record of 900.6 km/h (559.4 mph) over a 1,000 km (620 mi) closed-circuit course in 1955.
The crash record in early service was poor, mainly due to the inexperience with swept-winged aircraft and the lack of a two seat, dual control Tunnan trainer variant: this meant that Swedish fighter pilots could only be trained using two seat variants of the de Havilland Vampire (a straight-winged jet), before going solo in a Tunnan. 99 pilots were killed during military practice flights in Sweden.
The fighter version was retired from active service in 1965, but some aircraft were used for target towing up to 1974. The last official military flight was completed in August 1976 at the Swedish Air Force's 50th anniversary air show.
The Tunnan was the first Swedish jet aircraft to enter combat. In 1961, five J 29Bs were stationed in the Republic of Congo for a UN peacekeeping mission (ONUC), organized as the F 22 Wing of the Swedish Air Force. It was reinforced by four more J 29Bs and two S 29C photo reconnaissance Tunnans in 1962. Most of the missions involved attacking ground targets with internal cannons as well as unguided rockets. No aircraft were lost in action despite large amounts of ground fire.
Consensus of the crews and foreign observers was that the Tunnan's capabilities were exceptional. (Their secessionist adversaries used a few Fouga Magisters and other aircraft with relatively poor air combat capabilities.) The only aircraft lost was by a high-ranking officer who made a trial run and crashed during an aborted takeoff. When ONUC was terminated in 1964, some of the Swedish aircraft were destroyed at their base, since they were no longer needed at home and the cost of retrieving them was deemed excessive.