[BK m/90 from front and side] Mjölner, gliding stand off submunition dispenser

Series delivery to the Swedish Air Force has now of a gliding bomblet dispenser weapon system for Gripen and Viggen. Its official designation is Bombkapsel m/90, BK90, but is also named Mjölner, after the Norse god Thor's warhammer, which he could throw hard, far and accurately.


[BK m/90 from behind] As it is designed by DASA, formerly MBB, some details are similar to their MW1 dispenser for Tornado. DASA designation is DWS 24 (Dispenser Weapon System, 24 dispenser tubes), but it has also been referred to as DWS 39, as it was intended for JAS 39 Gripen.
Other dispensers in the same familiy includes:

DWS 16, approx  400 kg
DWS 40, approx 1000 kg
DWS 60, approx 1400 kg
The Swedish Air Force wanted a weapon that could be released at high speed and very low altitude very close to the target, as well as having a stand off range in cases where target position is known.


[BK m/90 from straight forwards] Dispensers such as MW1 and JP 233 always require you to overfly the target. Powered stand off dispensers do have longer range, but they have to be launched at higher altitudes and cannot be used at very close ranges. (They are also more expensive.)

General configuration

[General configuration]
                           The nose is 22% of total lenght.
           __    _         Submunitions section 68%, electonics
  ________/__|__/_|  \|_/  section 6%, tailcone 22%.
 /                |   | |  
 \________________|   |_|
          \__|  \_|  /| \  24 sideways firing launch  .o.o.o.o.o.o
  ________----___--        tubes, in this pattern:    o.o.o.o.o.o.
 <_______________ |        Diameter 12 cm, each with 3
                 --        submunitions.

Technical data

Length 3.505 m
Span   1.000 m  
Width  0.630 m
Height 0.595 m, fuselage 0.320 m 
Weight  600 kg  

Release altitude 30 - 500 m
Release speed M 0.6 - M 0.9
Flight altitude 30 - 200 m, terrain following
Range when launched at 50 m altitude and Mach 0.9 is more than 10 km in the direction the aircraft is flying, or 5 km to the side of the aircraft's path.

Navigation is by INS and radar altimeter.

The US DoD has in 1995 assessed its range, as the AFDS, Autonomous Free-flight Dispenser System (a development by a US subsidiary of DASA, CMD) from an F-16 to be 8 km from low altitude release and 22 km from 6100 m altitude. In that form it's also fitted with a GPS receiver.

The dispenser can be launched from very low altitude when the target "is almost under the aircraft's nose".

Air defence will have difficulties, as a large number of small targets will arrive from different directions in a very short time space.
[Schematic showing the flight path of four aircraft and their dispensers]

Submunitions

Two types of submunitions are carried, one the MJ1, a 4.0 kg air bursting warhead against soft targets; the other, MJ2 of 18 kg a proximity fuzed anti-armour warhead, also useful against semihard targets.

Immediately after ejection, submunitions are retarded by small chutes making impact point practically independent of speed and release altitude thus making computation easier for the dispenser.

Pattern is 250 m wide (also at low altitude), 300 - 400 m long.

Among the important targets mentioned by the Swedish air force are troops, bridge building equipment, (armoured) helicopters, aircraft and vehicles including APCs. Primarily it will be used against air delivered and other key units during an invasion.

DASA is testing derivate versions under the name Taurus (Target Adaptive Unitary and dispenser Robotic Ubiquity System), which is also the name of a new joint Bofors/DASA company:

which were flight tested early in 1996. Under the name KEPD 350 one version has been ordered by the German air force.

Related documents


(Source: Several issues of the Sw. AF magazine FlygvapenNytt and the Feb 1993 Air International and other magazines, additional information from DASA courtesy of Leif Pettersson)
Military aviation
Text last updated 1996 Jan 10, photos by me at Ljungbyhed 1996 Aug 25
Last modified 1998 Jan 25 by Urban Fredriksson
griffon@canit.se