A heavy mortar system with high mobility
Text: Jukka Nortio
Photos: Patria, Jari Saarentaus
Patria’s container-mounted 120mm Nemo mortar – the Nemo Container – is an excellent example of how Patria’s product development meets customer needs.
"We drafted our first plans for this kind of weapon more than ten years ago and even applied for a patent. The concept now meets customer needs," says Kari Reunamäki, Vice President of the weapon systems product line at Patria.
"One of our customers, the United Arab Emirates Navy, asked us whether Nemo could also be mounted on a transferable platform, not just fixed on a boat or vehicle."
The container can be easily moved into a firing position on a high-speed boat, a ship or on a truck; the container can also fire from any of these carriers.
Reunamäki is delighted that product development for this new weapon system has attracted the interest of customers.
"It’s great that the product has been the focus of considerable interest. When demand exists, there is no need to enter the market blind, wondering how things will work out," Reunamäki comments.
During the product development process, Patria’s experts were in touch with the United Arab Emirates Navy to ensure that the finished product took maximum account of customer needs. For example, the size of the container was decided in collaboration with the customer.
To be introduced to the public for the first time in February 2017, the Nemo Container will be the first container solution to mount a large-calibre weapon. While smaller-calibre, container-mounted weapons have been available, no Nemo-like mortar system, capable of both direct and indirect fire, has been on the market until now.
"To date, only smaller-calibre machine guns and automatic cannons have been mounted on containers."
The development of a new type of weapon system was possible thanks to the deep knowledge and long-term experience of mortar systems at Patria.
"A range of competencies are required in order to develop the knowledge needed for the integration of a heavy 120mm mortar in a container," Reunamäki says.
"We can use our weapon design expertise to conduct strength and vibration analyses related to the dimensioning of a container, for example. We know what is required for a container to withstand the recoil forces and impulse of the Nemo system. Vehicle or container manufacturers rarely understand the weapon system side of the equation.
Strength calculations and the design of the support frame were particularly complicated by the fact that the container had to include an access hatch, a top hatch and an escape hatch, which weakened its construction.
"When designing the chassis, we performed repeated strength calculations, in order to achieve a durable structure with optimal ergonomics."
The dimensions of the Patria Nemo Container are those of the standard 20-foot maritime container – and its fixing points are located in similar positions. Externally, it is no different to a standard container. The durability of the container is based on an additional support frame built between the external and internal cladding.
"The reinforced tubular structure absorbs recoil. There are more longitudinal and transverse beams in the space between the external and internal cladding than in standard containers," Reunamäki says, describing the construction.
In the firing position, the roof is 600mm lower than that of a normal maritime container. The standard height is achieved when the mortar’s transport cover is added to the top of the container.
"In the transport position, Nemo’s turret is completely hidden by the transport cover. During transport, the turret is in a direct-fire position, pointing in a different direction than during firing. The turret is rotated 180 degrees when the weapon is being used for firing. The muzzle must be located beyond the edge of the container to avoid excessive stresses in the container created by the muzzle blast," says Reunamäki.
Nemo Container meets the requirements stipulating that a mortar must be capable of flexible transfer from one location to another using suitable equipment. It is also a cost-effective solution.
"Nemo Container is significantly more cost-effective than mortar systems mounted on a separately purchased vehicle or boat."
The Nemo Container is delivered with everything that a mortar unit needs: protection for the crew, the weapon and ammunition. The container has its own power unit and air conditioning. In addition to an access hatch, the container has an escape hatch.
The customer can select NBC (Nuclear, Biological and Chemical) filtration systems, as well as the desired ballistic protection, made either of steel plates or ceramic armour. High-durability steel plating 8 to 10mm thick adds around three tons to the weight of the container.
The container has space for one hundred mortar bombs – double the number compared to that of the Nemo AMV vehicle version, for example. The container has a crew of three: two loaders and a gunner, who also acts as the commander of the unit.
The key benefit of the Patria Nemo Container is its easy mobility, which is unique to mortar systems of this calibre.
"The container can be easily moved into a firing position on a high-speed boat, a ship or on a truck; the container can also fire from any of these carriers. For example, the container’s versatile mobility enables coastal jaeger platoons to relocate this independent firing unit during a mission. This is also an excellent solution for protecting bases."
The container can also be purchased as a separate unit without the weapon system, in which case the customer can make cost-effective use of its existing Nemo equipment.
Nokian Metallirakenne manufactures the container according to Patria’s specifications. Patria itself installs the Nemo system, ammunition storage and the crew stations. The crew station comprises computers, controls, cabling and seats.
"The container manufacturer provides us a fully equipped container with a power unit, air conditioning device and a completed container frame."
The first Patria Nemo Container will be completed for the IDEX exhibition, to be held in February 2017 in Abu Dhabi.
"Before the exhibition, we will test the functionality of the system, such as the electric system and fire control. After the exhibition, we will proceed with test firing and strength tests. After these tests are completed, we will be ready to deliver Nemo Containers to the customers," Reunamäki comments.