Saab 35 Draken
From Scramble - The Aviation Magazine
|Saab 35 Oe Draken|
|First Flight||25 October 1955|
|Maximum takeoff weight||kg||lb|
|Engines||one Volvo RM6A turbojet engine|
|Thrust||kN (each)||lbf (each)|
|Rate of climb||m/min||ft/min|
|Avionics||Ericsson PS-03/A radar|
|Armament||Two ADEN30 30 mm guns|
In 1949, the Royal Swedish Air Board issued a request with the designation Project 1200 for a new interceptor that would follow the Saab 29 Tunnan. This new aircraft was to have a speed of at least Mach 1.4; be able to operate off specially-built sections of public roadway under the Swedish BASE 90 distributed airbase scheme; and was to be rugged, easily maintained, and cheap to operate. Saab developed Project 1250, with a radical sweepback of 70o, followed by a double delta scheme, featuring a thick inner delta with a sweep of 80o providing accommodation for fuel and landing gear, and a thin outer delta with a sweep of 57o providing additional lift for low-speed flight and short-field operation, while retaining low-drag characteristics for high-speed flight. The wing scheme was validated using a 70% scale demonstrator aircraft, the Saab 210 LillDraken (Little Dragon). In August 1953, the Swedish government ordered three prototype and three preproduction Saab 35 Draken, based on the LillDraken design. The Avon 200 turbojet was selected as the powerplant for the production machine. A license was obtained by Svenska Flygmotor (later Volvo Flygmotor) to manufacture the Avon.
Fighter version, first flown in 1958 and 90 delivered between 1959 and 1961. The J35A Adam was fitted with a Cyrano II radar, - locally designated Ericsson PS-02/A - and armed with two ADEN30 30 mm guns and two AIM-9B (aka Rb24) missiles. The Volvo RM6 turbojet was rated at 61,3 kN, enabling a dash-speed of Mach 1,53. MTOGW 9,2 tons.
Fighter version, first flown 29 November 1959, 73 built and delivered between 1962 and 1963. The J35B Bertil had improved Ericsson PS-03/A radar and gun sights, and was also fully integrated into the Swedish STRIL 60 system, allowing the J35B to perform collision course intercepts, hitting the target from the front or the side with Bofors 75 millimeter (3 inch) folding-fin unguided rocket pods, carried by two 19-round pods. 2nd hand J35B airframes were sold to the Finnish Air Force as Saab 35BS.
25 J35As were rebuilt into a twin-seated unarmed SK35C Caesar trainer, first flown on 30 December 1959. 2nd hand SK35C airframes were sold to th Finnish Air Force as Saab 35CS.
J35D David fighter version, first flown 27 December 1960 (converted J35A prototype), 120 delivered between 1963 and 1964. Powered by the more powerful Avon 300, locally designated RM6C, rated at 77.3 kN thrust. Since the RM6C proved to be thirstier, the J35D replaced the centerline pylon with twin side-by-side fuselage pylons, both of which were wet. The wing pylons were also wet, meaning the J35D could carry four external tanks instead of one. Proved to be the fastest Draken version, capable of reaching Mach 2.
S35E Erik reconnaissance version, first flown 27 June 1963, total production 60. The radar and the armament was removed and several cameras (of ortho and oblique types) fitted. The aircraft was unarmed but was fitted with a chaff-flare dispenser in place of one of the wing tanks. A total of 28 aircraft were re-built J35Ds.
The J35F Filip was much like a late-production J 35D. 230 delivered between 1965 and 1972. This variant had improved electronics and avionics, e.g. integrated Ericsson PS-011/A radar, aim and missile systems. The aircraft's main armament were IR and SARH versions of the AIM-4 Falcon (Rb27 radar model and Rb28 infra red model) missile originally intended for the J35D, but one of the cannon was removed to make space for more avionics. Later production J35Fs were fitted with a Hughes AN/AAR-4 IRST, built under license by Ericsson. Machines with the IRST were designated "Filip Tvaa" or J35F2, with the early machines retroactively designated "Filip Ett" or J35F1. 2nd hand J35F2 airframes were sold to the Finnish Air Force as Saab 35FS.
Proposed export version for the Swiss Air Force as a replacement for their antiquated de De Havilland Vampires in the interceptor role. The J35H was to be fitted with Ferranti AI23 Airpass collision-course radar system, used in the English Electric Lightning. The evaluation of the J35H went well, but the Swiss opted for the Dassault Mirage III instead. A later proposal for an export attack variant, the "AS 35X", where "X" stood for "Export", with a dogtooth wing and General Electric J79 engine, also went nowhere.
Designation for modified 66 J35F2s airframes. J35J Johan upgrades included structural strengthening, modern electronics and cannon, additional two AIM-9P Sidewinder (Rb24) pylons under the air intakes and increased fuel capacity. 67 upgrades from low-time J 35F2s were performed in all, with the last re-delivered in August 1991. The final operational J35J sortie was in 1999.
In the mid-1980s, Saab rebuilt 24 J 35D aircraft into the J35Ö version for export to Austria, armed with AIM-9P5 all aspect Sidewinders, RWRs and chaff-flare dispensers salvaged from retired Danish Drakens. Replaced by Eurofighter Typhoon fighters.
Export model for Finland (Suomi). 12 fighter version units for the Finnish Air Force. The J35S was similar to the J35F, but had twin ADEN30 cannon and a revised avionics suite. built by Saab and assembled under licence by Valmet in Finland. Updated with new avionics, cockpit displays, navigational/attack systems, and electronic countermeasures during the 1990s, but these were finally retired in 2000 to be replaced by F/A-18C/D Hornets.
Export model based on the J35F for the Royal Danish Air Force, local designation F-35. The type was heavily modified with greater fuel capacity, a maximum external warload of 4,500 kilograms (10,000 pounds) - including the AGM-12 Bullpup, structural reinforcement, a new outer wing, stronger landing gear to handle greater weights and a runway arresting hook. Deliveries included 20 A35XD (aka F-35) single-seat strike aircraft, 20 S35XD (aka TF-35) two-seat trainer and 11 SK35XD (aka RF-35) reconnaissance models. During the WDNS upgrade of the 1980s they received the AN/ALQ-162 jammer, a Marconi 900 HUD and Ferranti LRMTS.
- Austrian Air Force (retired)
- Finnish Air Force (retired)
- Swedish Air Force (retired)
- Royal Danish Air Force (retired)