Manufacturer: Saab
Application: Fighter-bomber
Length: 15.34m
Height: 9.42m
Wingspan: 3.89m
Empty weight: 8,000 kg
Full weight: 16,100 kg
Engine: Volvo Flygmotor RM6C
Engine thrust: 5,807/8,013 kg
Max speed: 1900 km/h/Mach 1.8
Max allowed speed, per flight manual: 1350km/h
Cruise speed: 950 km/h
Max altitude: 18,300 m
Crew: 1
F-35 Draken was considered a very simple aircraft when it came to weapon delivery, with pilots having to rely on little more than a compass, a map and a gyrostabilised optical sight. By the end of the 1970s, a program under the name of “Weapons Delivery and Navigation System” (WDNS) was begun to fix these issues. The avionics were updated with stuff such as a Lear-Siegler nav-attack computer, a Singer-Kearfott inertial navigation system, a Marconi Series 900 head-up display (HUD) and a British Ferranti laser rangefinder & marked target seeker (LRMTS, similar to that fitted to British Harrier GR.3s.). All of these systems could be fitted into the casing of the existing RF-35 nose with minor modifications, so all aircraft adopted this design with this upgrade.
It was also given a set of electronic countermeasures, with an early update being the addition of ALR-45/APR-37D radar warning receiver system, In the mid-1980s this system was upgraded to the much more user-friendly AN/ALR-69 system.

Furthermore, the EW package got expaned to the new and improved Enhanced Modular Flare and Chaff Dispenser (EMFCD), which were introduced with the AN/ALQ-162 jamming system(F/RF). This system was installed in a small pod integrated on the left wing. To counterbalance this addition, a pod of identical shape was installed on the right wing, but instead of the jammer system, this pod had the option for 5x11 countermeasure cassettes to be installed on the outwards-facing side. Another option was removing the AN/ALQ-162 entirely from the left wing, and replace it with another one of these EMFCD pods, suddenly giving the aircraft an additional 110 countermeasures to work with (F/RF).
EMFCD also brought an upgrade to the airframe itself, with an additional 12 flares being installed in the wing root of the right wing facing downwards.

Subsequently, the new airframe had 24 permanent flares installed at all times, and the option for 178 flares if all 14 of the 11-piece cassettes were switched to flares. The aircraft carried a minimum of 24 flares, and a maximum of 154 chaff. Any combination of 11-piece intervals were possible beyond this.
When the airframe was equipped with the AN/ALQ-162, 55 countermeasures would be subtracted from the 154 interchangeable dispensers (F/RF).
WDNS was meant to keep the F-35 highly capable into the mid-1990s
In 1984 the F-35 was certified to carry te MK20 Rockeye 500lbs clusterbomb, as Runway Catering Bombs were deemed advantageous for their capability.
In 1885 the French Matra Durandal was also test mounted on the aircraft, however the FKO (Forsvarskommando/Defence Command) stepped in before it was officially certified to utilise this weapon, as no deal of acquisition had been signed yet.
During the 20th to 23rd of February 1989, the aircraft was tested with, and certified for, Canadian CRV-7 rockets using the 19-hole LAU-5003/A launcher.
A bit more of a stretch, but in the period between 1984 and 1985, the FMK looked into the possibility to replace the 30mm ADEN cannons with the 20mm M39, also used on the F-100. This gun had a barrel bearing in the Super Sabre, but this could not be fitted onto a Draken. The modification was carried out on a spare S35E aircraft body Denmark had bought for spare parts, without the barrel bearings. The M39 proved to be significantly more accurate than the 30mm ADEN during their ground tests, and the FMK suggested testing this configuration for Air-toAir and Air-to-Ground shooting. The project never got further than this though. Since the tests were never carried out on a 35XD frame, it can be debated whether or not this modification should be an option at all, but it was tested on a grounded S35E and worked remarkably well.
In 1977, following the retirement of the T-33, the AN/ALE-2 chaff pods needed to be transferred to a new airframe. The only airframe in the RDAF that could deploy these pods without modification was the F-35, and so they were adopted to the twin-seat TF-35 only. This model never received EMFCD pods, but was instead given a modified AN/ALE-2 chaff pods, where the internals had been stripped out and replaced with the internals of the AN/ALE-38 chaff pods and some minor Danish improvements. This chaff pod was designated A38DK. They could be mounted on pylon 1R/L. The twin-seat configuations of all Danish aircraft at the time had the capability to be “offensive support” aircraft, by crowding and confusing enemy radar with chaff dumping.
In 1982 the AGM-12B Bullpup was phased out of arsenal, which lead to all cockpit installations and outside antennae to be removed from all airframes.
Near the end of the 1970s, the BLU-1 was also phased out of use on the airframe.
This caused the WDNS modification as a whole to sport a different loadout, which consisted of;
- 2 ADEN 30mm machine cannons (F/RF, TF 1 ADEN 30mm)
- 9 M117 750lbs bombs
- 9/14 MK82 500lbs bombs/MK82LD Snakeeye bombs
- 9 MK83 1000lbs bombs
- 9 MK20 Rockeye 500lbs clusterbombs
- 8 LAU-3/A rocket pods with 19 FFAR/CRV7 rockets each
- 2 A38DK chaff pods (TF, 1R/L)
–Exclusively on the outer most pylons (2R/L) - 2 AIM-9B FGW Mod.2
- 2 AIM-9N-2
- 2 AIM-9N-3 DE-84
– New EMFCD pylons after 2R/L - 2 EMFCD pods, 110 countermeasures (F/RF)
- 1 EMFCD pod (right wing), 1 AN/ALQ-162 (left wing), 55 countermeasures + jamming (F/RF)
A series of new Sidewinders were introduced with the upgrade. The AIM-9N-2 was a modified AIM-9J featuring an improved SR116 rocket motor with a burn time of 3.2 seconds. This increased the range and speed of the missile, while also having reduced smoke from the standard AIM-9N.
AIM-9N-3 DE-84 is an upgrade of the AIM-9N-2 with the IR proximity fuze replaced with a detector operating using active laser radiation.
http://www.esk729.dk/esk729.dk/Forside.html
http://www.draken.dk/Flyvevaabnet/FlyvevaabnetsFly/Draken.html
https://www.airvectors.net/avj35.html
http://www.stall.dk/flyvevaabnets-historie-fra-1945/fly-gennem-tiden/draken.aspx
–Books/Manuals
Flight Manual F/RF/TF-35 Vol. 1/Vol. II SAAB 35XD
Saab F-35 DRAKEN T.O.1F/RF/TF-35-1½
Lockheed F-104 STARFIGHTER T.O.1F/CF-104/D-1½ (additional ordnance details)
- Yes
- No
If you would like some more inside into the background of this aircraft, I have made a different suggestion on the original model of the F-35.