Finnish Defence Forces to develop mortar mobility by a new system

In the Army, a project is underway to develop mortar mobility by a new, modular and mobile 120mm mortar M3 weapon system.

The Army has developed in co-operation with the Finnish Defence Forces’ Logistics Command and Patria Land a new, heavy M3 mortar system (M3 denotes Modular Mobile Mortar), the pre-series of which will be procured by the FDF Logistics Command from Patria Land. The new mortars will be delivered to the Army during 2025. The total value of the procurement will be EUR 4,7 million excluding VAT. 

Heavy mortars are used to provide support for forces in combat. In the future, the role of mortars will become more prominent as the forces’ organic heavy fire units of indirect fire.

The new weapon system will be fitted and mounted onto a vehicle top from which a request for fire will be executed directly, resulting in increased mortar mobility. The system will utilise the already existing barrel and battle management system that have been integrated to the module with magazine, recoil mechanism and inertial navigation system. The module allows fires from practically all standard container-lock-fitted vehicles. In case of vehicle malfunction, the module can be transfered to another vehicle to continue mission execution.

The mortar remains ready for fire direction without specific preparations in all types of soil, and its firing capacity equals at least that of a towed mortar. Finnish-made with security of supply for its components and sparts, the weapon system is easy to operate and cost-efficient.

– The new M3 system will improve our forces’ mobility, protection, and effectiveness. The development of the system sets an example of co-operation that has advanced quickly all the way from concept generation, to prototype test fires, to testing the system, to pre-series requirement specifications, to its operational concepts and tactics. The pre-series systems to be procured will be fielded for use case experiences, and the decisions concerning possible additional acquisitions will be made at a later point in time. The objective is to start conscript training using the new mortars during 2026, says Inspector of Infantry, Colonel Ari Lehmuslehti from the Army Command.

Movement and maneuver are decisive

The development of mortar mobility is threat-driven. An unfortified mortar has no protection to counter air-to-ground threats, and it remains easily detectable while conducting a request for fire. Modern weapon locating radars are almost immediately able to track and calculate the start point for a trajectory of a mortar projectile. A firing position may also be identifiable from the air by, among other, satellites or drones even in case of no fires from a firing position. Also, engaging targets at long range will not alone provide protection.

An efficient technique for threat-reduction is to execute a request for fire rapidly at a non-prepared firing position and to relocate immediately after firing. Good tactical movement and maneuver will also compensate for projectile ranges. A vehicle-fitted mortar system allows executing the request for fire closer to the target and enables relocating after mission completion.

For additional information on mortars, see the Finnish Defence Forces’ equipment catalogue:

-    Light mortar 81 KRH (puolustusvoimat.fi)
-    Heavy mortar 120 KRH (puolustusvoimat.fi)
-    Armoured Mortar Vehicle XA-361-AMOS (puolustusvoimat.fi)