were typically in excess of predicted values. Production commenced In 1948 and in May 1951, Bråvalla Wing (F 13) received the first production aircraft. The Tunnan was produced in five main variants. The J 29A fighter was the first model to enter service, and was followed by the J 29B and J 29E fighters, and finally the afterburner-equipped J 29F fighter, which was the final variant built. There was also a dedicated reconnaissance variant, the S 29C. Between 1950 and 1956, 661 Tunnans were completed, the largest production run for any Saab aircraft. Design The Saab 29 Tunnan was the first Swedish aircraft to be specifically designed to use jet propulsion. Sweden's first jet fighter, the Saab 21R, had been modified from the piston-engined Saab 21. It is a small, chubby aircraft with a single round air intake in the nose, with the pilot under a bubble canopy directly above the air intake duct on the upper-forward section of the fuselage. It has a very thin mid-mounted moderately swept two-spar wing which is a single structure attached to the fuselage by four bolts. The undercarriage is hydraulically operated, and was designed to be suitable for use from rough airstrips. To improve pilot survivability, the Tunnan used an ejection seat Saab developed in 1943, with an explosive jettisoning system for the canopy. The Tunnan is powered with a single de Havilland Ghost turbojet which have a top speed in excess of , better performance than Sweden's de Havilland Vampires. The engine was bolted to the fuselage at three points and a special trolley was used to remove the engine for maintenance. The final version had an afterburner, the first successful one used with a British jet engine. Improvements were made to the wing to incorporate a dog-tooth leading edge, raising the critical Mach number. From 1963 onwards, all frontline J 29Fs were equipped with AIM-9 Sidewinder infrared-seeking air-to-air missiles. Operational history Sweden The J 29 was fast and agile, and set the world speed record on a 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 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