The AS90 is a modern tracked 155mm self-propelled howitzer of British origin. The AS90 was developed in the 1980's and was selected in 1989. The first units were in active service in 1993. AS90 stands for Artillery System for the 1990's. The official UK military designation is L131.

The AS90 has a conventional layout. The crew of five consists of a commander, driver, gunner and two loaders. The driver is seated in the front hull with the drive train to his right. The turret is mounted at the rear and houses the rest of the crew.

The AS90 is armed with a 155mm L/39 howitzer connected to a fully automatic loader. The maximum range is 24.7km and 30km with assisted ammunition. A burst rate of fire of 3 rounds in less than 10 seconds can be achieved. The maximum rate of fire is 6 rounds per minute and sustained fire is 2 rounds per minute. A total of 48 projectiles are carried. A 52-caliber barrel is available. A MAG machine gun is mounted on the turret roof for self-protection.

The AS90 is operated under full armor protection. The thick steel armor provides protection from small arms fire, shell splinters and 14.5mm rounds over the frontal arc. An NBC and fire extinguishing system are standard and 10 smoke grenade dischargers are fitted to the turret.

The tracked chassis provides the AS90 with a good cross country performance. A Cummins 660hp diesel engine provides propulsion and an APU provides power when the engine is not running. Due to the weight of the system the speed is somewhat limited.

The AS90 is only used by the United Kingdom. A total of 179 units have been produced of which a large quantity will be phased out to be replaced by a lightweight and highly mobile piece of artillery. In Poland the Krab, which is an AS90 turret mated with a local chassis, is undergoing trails.