Sisu and Patria Have Created New Self-Propelled Mortar

Finnish companies Sisu and Patria have created a new self-propelled mortar based on the Sisu GTP 4×4 armored vehicle and the Patria TREMOS mortar.

A photo of the new mortar was published by Sisu on its X page.

The latest Finnish self-propelled mortar system based on the Sisu GTP 4×4 armored vehicle with the Patria TREMOS modular mortar system was presented at the DALO Industry Days exhibition in Denmark.

According to SSBCrack News, this partnership builds on the previous success with Finland’s ARVE self-propelled artillery, which integrates Patria’s 155 mm 155K98 gun with a Sisu E13TP 8×8 truck.

The acronym TREMOS stands for Traditional REborn MOrtar System. The system was presented at the Future Mortar Systems conference in London in late October 2024. Subsequently, the Finnish Defence Forces announced their intention to purchase the system under the 120 KRH M3 index, with the delivery of a pre-production batch in 2025.

The Sisu GTP TREMOS system allows the integration of 120 mm or 81 mm mortars. Key capabilities include a top speed of over 100 km/h for rapid movement after firing. The rate of fire is 12-15 rounds/min; the first three TDF can be fired in 15 seconds, and the opening of fire is possible within 60 seconds after arrival.

The basic chassis of the Sisu GTP is based on the Mercedes-Benz Unimog. It has an improved suspension and its payload is 5 tons and it has a range of more than 700 km.