The journey to the Viggen
Development work on what would become the SAAB 37 Viggen aircraft began as early as 1952, three years before the SAAB 35 Draken aircraft first flew. This shows how rapid the pace of aircraft development was at that time. Planning began for a Draken replacement even before it had flown for the first time, and similarly for the SAAB 32 Lansen the same year as that aircraft first flew!
Many projects – Many ideas
The first project was called the 1300 with several different solutions. The first requirement was for a fighter aircraft to intercept supersonic bombers at high altitude. Then came the desire for a ground attack aircraft that could destroy enemy air bases and missile ramps. Over 100 different proposals were put forward under the project heading, of which the one furthest along was aircraft A 36. In 1956 project 1350/36 was launched, followed by 1400. The first was more specifically intended to be a further development of the SAAB 32 Lansen and 35 Draken, but project 1400 was means to plan for a new aircraft to be delivered 2 or 3 years or so after delivery of project 1300.
Project 1300 ended in 1956 and project 1350/36 took over as the principal aim. It became evident that Aircraft A 36 would be far too expensive, and the designers moved on.
Money became tight
The Air Staff who controlled the direction of development began to have financial constraints and in the mid-1950s there were many who believed that drones and missiles would soon replace all manned aircraft. Hence the Air Staff pressed for as cheap aircraft as possible.
As a result the above-mentioned projects were abandoned, and even project 1400 was the last throw in an attempt to produce a less expensive alternative. However missile projects were assigned priority over aircraft. As a consequence all of SAAB’s projects were halted.
SAAB was forced instead to work on its own with various ideas and existing production, but in 1961 came a turning point when the Air Staff brought out a new requirement specification for a new fighter aircraft project called 1500/37. Now all the old project studies became useful.
The all-in-one aircraft was born
Most interesting as far as project 1500/37 was concerned was its vision of an all-in-one aircraft that would be capable of performing all three principal tasks, interception (Jakt), ground attack (Attack) and reconnaissance (Spaning). Another requirement was for it to be capable of operation from unprepared runways only 500 metres long. It should be supersonic at low height and fly at twice the speed of sould at great height.
SAAB acted quickly and presented a number of proposals as soon as March 1961. In September a new specification arrived at SAAB with somewhat more limited requirements. Now the requirement emphasised an aircraft able to attack at low height that could replace the SAAB 32 Lansen. It should exceed Mach 1 at low height and be easy to service in the field. Its weight should be about 10 tons.
SAAB proceeded and in June 1962 the proposal was selected that would form the basis for the development of aircraft 37. From this moment it took about 5 years before the first prototype took off on 8 February 1967 with pilot Eric Dahlström at the controls.
The Viggen became the first aircraft in series production to be equipped with canard wings (foreplanes), small additional aerofoils on each side of the cockpit. These aerofoils contributed to the short take-off distance that was a requirement. In the event of a conflict aircraft would be spread out over a large number of small field air bases that to some extent utilised roads.
Long runways were a luxury that the Viggen must do without. For stopping, reverse thrust was developed, whereby the engine thrust was directed forward, allowing the pilot to use engine power to come to a halt in a very short distance.
Viggen was produced in several versions. Here is a two-seater trainer SK37 taking of showing the peculiar two wheeled undercarriage. Note that the large payload is not a bomb but a drop tank for extra fuel. Photo Peter Langsdale.