BvS20AS

AB BOFORS BvS20AS is an air-transportable, medium-weight, turreted self-propelled howitzer based on the proven technology of the Haubits FH77 howitzer in service with the Royal Union Army. The system is fully autonomous and provides the highest performance, but with reduced cost, crew levels and weight.

The intention was to integrate the gun module into available in-service chassis and after a number of proposal BOFORS decided to use the BvS10 chasis in order to satisfy the Royal Union Army requeriments.

The development programme was started in early 2003 and a fully functioning demonstrator started in the second quarter of 2005. The demonstrator included a fully automatic loading system which loads the projectiles and the charges.

In 2007 the Royal Union Army ordered the first 150 units of a total 600 units until 2011.

Gun module
The system is operated by a crew of two. The BvS20AS uses the main gun components from the FH77 – the barrel and elevating mass, the shell loader and flick rammer. The system also has a separate dedicated auxiliary power unit. The turret is of lightweight aluminium armour construction.

The 12.5t turret carries 30 projectiles and charges. The autoloader is based on a modified shell loader and an automatic charge loader. The charge loader will automatically compose the selected charges using any Joint Ballistics Memorandum of Understanding (JBMOU) compliant charge module. The autoloader is powered by a 24V electrical supply.

A lifting system is installed at the front of the turret allowing the crew to reload the magazine from outside the vehicle. The ammunition feed has an automatic inductive fuse setting system. The pneumatically operated flick rammer rams the shells into the breech with elevation angle-dependent ramming pressure control.

Chasis
The BvS10 chassis was modified with stronger torsion bars and extra shock absorbers. The crew cabin is separated from the firing module. The crew cabin is fitted with a computerised fire control system with the TERMA armament ballistic kernel software implemented and linked to the artillery command and control system or to other command and control systems. The system can be loaded and fired manually.

The cabin provides protection against small arms rounds, anti-personnel mines, bomblets and nuclear, biological and chemical warfare attack.

Performance
The BvS20AS can fire against stationary and moving targets at a rate of six to eight rounds a minute including Multiple-Round Simultaneous-Impact (MRSI) firing. Using standard rounds the maximum range is 30km; this is increased to more than 40km with base bleed rounds.