SAAB 35 DRAKEN, a short history 1993 July 24 Urban Fredriksson urf@icl.se Draken means The Dragon (or perhaps "the Kite" :-). The project "1200" to find a replacement for Saab 29 Tunnan ("Flying Barrel") started in 1949. It was intended to be an interceptor able to counter bombers flying at M 0.9 at high altitudes. To test the double delta that was a combination of a delta and thin swept wing, construction of aa small concept aircraft, Saab 210, was started in May 1950. It flew for the first time 21:st Jan 1952. (It made a 1 s small hop in Dec 1951, by mistake.) This proved to be a layout that combined good high speed properties with a low enough take off and landing speed. Intended engine for Draken was the Swedish STAL Glan, whose design was never finished, but in 1952 it was decided to go for Rolls-Royce Avons instead. In Jan 1953 the air force ordered three prototype and three series aircraft of type "35". The first prototype flew first on 25:th Oct 1955. Its engine was a RR Avon Mk.21 (RM5A in Sweden) without an afterburner. Even though speed and good climbing performace was the priority, the aircraft later showed itself to be good dogfighter too. Its instantaneous turn rate is very good, but as is typical for delta winged aircraft, induced drag bleeds off a lot of energy during turns. In order to enable it to operate from partially damaged runways and stretches of highway, it was given a brake chute to decrease the landing run. Emphasis was placed on the ability to be serviced quickly by conscripts with relatively short training. A team of seven, of which six conscripts, are supposed to be able to re-arm and re-fuel an aircraft in less than 10 min. Emergency power is supplied by a ram air turbine just behind the nose gear, extended either on hydraulic power failure, or on manual command. Can only be retracted with the engine running. Designations: J, Jakt = Fighter/interceptor Sk, Skol = Trainer S, Spaning = Reconnaissance SWEDISH AIR FORCE VARIANTS designation number delivered in service serial numbers ----- J 35A short 65 1960-61 -1976 35001-35065 RM6B (= RR Avon Mk.48A) with afterburner "type 65" Delivered without radar nor sights. Later given Thomson-CSF Cyrano radar. While unarmed, they served a single engined trainers, both for pilots and ground crews. J 35A long 25 1960-61 -1976 35066-35090 Longer afterburner , "type 66" to increase max altitude, otherwise as A short. Remaining A:s equipped with undernose IR-detectors (not the same as the F:s had) in 1966-67. ------ J 35B1 72 1962-63 35202-35273 Delivered without radars, 69 konverted into J 35B during 1964-65. Weapons as "A" variant. Engine as "A long" J 35B 69 1964-65 -1976 Zero altitude (but not zero speed) rocket seat. Improved control system. ------ Sk 35C 25 1962-63 -> 35801-35825 Two-seat trainers, rebuilt from J 35A short with same engines. At first it was thought that a trainer version would not be needed, as the company test pilots considered it easy to fly. Most air force pilots didn't agree. As we have a long term commitment to train Austrian pilots, the last 5 in service may remain after Draken is retired as a fighter. ----- J 35D1 block 1 30 1963 35275-35304 RM6C (=RR Avon Mk.60) with afterburner "type 67". Required the air intakes extended further forward. Delivered without radars. In storage most of the time until 1966. J 35D1 block 2 24 1964 35305-35328 J 35D2 block 3 66 1964-65 35329-35393 First variant to have rocket seat (0 altitude, 100 km/h) as newbuilt. (Aircraft of all variants remaining in service later got "generation 2" seats.) J 35D 120 -1968 -1984 35274-35393 D1 and D2 designations abolished when all D1:s rebuilt into D2 standard. The D variant was first thought of as B2. It has a more powerful engine, so air intakes extend further forward; 600 litres larger internal fuel capacity as well as two 530 litre external tanks. ----- S 35E 30 1965-66 -1981 35902-35931 S 35E 29 1966-68 -1981 35932-35960 Rebuilt J 35D1 block 1, retaing the 'older' style canopy, the first 30 had the 'F-style' canopy. 3 SKa 24-600 long focal length cameras, one in the nose, two in place of the guns; one forward facing SKa 16B, one downward looking wide angle Ska 24-44 and two sidelooking SKa 24-100 all in the nose, all made by OMERA/Segid in France. Engine as "D". ------ J 35F1 230 1965-72 -1989? 35401-35630 J 35F2 <---- above includes F2 -----> F2 was fitted with IR-detectors from the beginning, F1:s never had one. ----- J 35J 66 1987-91 -1997? probably classified Extensively rebuilt J 35F:s ----- "Missing" serials are mostly aircraft retained by the manufacturer. There were 13 (*) prototypes, of which at least the first five were originals, the rest were probably converted series aircraft. No serials officially available for F and J, as they are still in service. (*) 14 if you count the demonstration aircraft J 35H (Helvetica), so total number produced in 1954-1989 is 612. ----- | Weapons options. All later variants can carry | all external weapons earlier can. _ n _ -----<_>(.)<_>----- Built in: 2 x 30 mm Aden guns with 150 rounds each J 35A "short" T 530 litre external tank x x x x 4 x Rb 24 (AIM-9B), firably singly or in pairs Inverted "Y" pylon under centre fuselage. ----- J 35A "long" rrr rrr 12 x 135 mm rockets for ground attack rrr rrr ----- J 35B R R 2 pods of 19 x 75 anti-aircraft rockets. A single salvo. ----- Sk 35 C is a totally unarmed trainer. ----- J 35D has the "Y" pylon replaced with two separate. T T 2 x 530 litre tanks. ----- S 35E is an unarmed reconnaissance version T T T T 4 x 530 litre tanks iii iii 6 x 80 kg magnesium flash bombs. KB BOX-9 chaff/flare dispenser MSK Night recce pod, IR film cameras and electronic flashes. ----- J 35F Left gun removed to make space for electronics. x x x x More missile types: Rb 27 (AIM-26B), Rb 28 (AIM-4C) and Rb 24J (AIM-9J) ----- J 35J has wing pylons wet; extra pylons under forward wings. x x x x x x 6 x missiles: Rb 24J (AIM-9J), Rb 27 (AIM-26B). T T T T 4 x 530 litre tanks. EXPORTS Finland Saab 35BS 6 Reworked J 35B Saab 35F 24 Secondhand Sk 35C 5 Secondhand Saab 35XS 12 Almost as J 35F, built in Finland 351301-351312 Denmark (Saab 35XD) F-35 20 Delivered with plain nose, now given laser 351001-351020 rangers, so they look a lot like RF-35s RF-35 20 Reconnaissance, cameras in nose similar 351101-351120 TF-35 11 Two-seat trainer 351151-351161 All has higher gross weight than Swedish versions, due to more internal fuel. Delivered with weapon pylons under the air intakes. Austria Saab 35OE 24 Reworked J 35D:s. No missiles, but they are now considering it. ----- Data for variants J 35A short - S 35E: Lenght: 15.21 - 15.34 m, Span: 9.4 m, Height: 3.9 m, Wing area: 49 m^2 Empty weights: 6590 - 7311 kg, Max take off weights: 10089 - 11973 Engine thrust: 4890 - 5845 kp; 6520 - 7880 kp with afterburner Take off run: 413 - 774 m, Landing: 810 - 921 m; 510 - 680 with chute Internal fuel: 2240 - 2820 litre, External: 1, 2, or 4 x 530 litres Data for J 35J Empty weight: 8500 kg, Max load: 2000 kg, Max take off weight: 15000 kg Engine thrust: 5845 kp; 7880 kp with afterburner Max speed: Mach 2.0 The Danish F/RF-35s have slightly larger span, the same number of pylons as J 35J, larger 1100 litre tanks and are thus quite heavier. [Main source: the magazine Kontakt, issue 93]