The main problem of mortars at all stages of their existence was mobility. The calculation could not have time to fold and leave the position and because of this fall under enemy fire. With the development of technology, it became possible to install mortars on self-propelled chassis, but this was also less useful than we would like. This time, the detection means were "spoiled" - the mortar mine has a relatively low speed and a specific flight path, which makes it easier for the enemy to detect the position of the mortarmen using radar stations. Accordingly, after detection, a blow will soon follow. The exits were obvious: reducing the time for preparing for shooting, and most importantly, for leaving the position; improving the rate of fire of the mortar and increasing the speed of the ammunition.
Sweden and Finland, represented by BAE Systems Hagglunds and Patria Weapon Systems, respectively, in the late 90s, decided to jointly solve all the problems of self-propelled mortars at the same time. The task was, to put it mildly, difficult, but both firms coped with it. Responsibilities were distributed as follows: the Finns make the mortars themselves, and the Swedes - the gun turret and related systems. The project was named AMOS (Advanced MOrtar System - Mortar system of the future). An eight-wheeled armored personnel carrier made by Patria was initially chosen as a chassis for a self-propelled mortar, and later the AMOS turret was installed on the CV90 armored platform chassis.
Initially, two prototypes of the gun turret were created. Both of them had two 120 mm mortars. All their differences were based on the fact that instance "A" had muzzle-loaded mortars, and the prototype "B" mortar was breech-loaded. In addition to the features of the loading system, there were significant differences in the firing range: the breech-loading mortar hit three kilometers further than the muzzle-loading one. Thus, the maximum combat range of AMOS at this stage reached 13 kilometers. Polygon comparative tests of the two prototype towers were carried out on combat vehicles with a wheeled chassis. The range, ease of loading and some other advantages of the B prototype quickly left no doubt which version of AMOS would become the basis for a serial combat vehicle. The turret with breech-loading mortars was installed on the CV90 chassis - a promising Swedish single platform for a whole family of armored vehicles. Once again, Tower B has proven its worth. At the same time, it was possible to find out the behavior of the tracked platform with a gun turret installed on it.
The AMOS system, like other mortars, is primarily intended for firing from closed positions. For this reason, the tower only has bulletproof booking. Nevertheless, the designers also provided for the possibility of direct fire: vertical aiming of both mortars is possible within the range from -5 to +85 degrees. Horizontal guidance is provided by rotating the turret; there are no dead zones. The mortars are equipped with a semi-automatic loading system, thanks to which a burst of ten rounds can be fired within four seconds. For self-defense, a 7.62 mm machine gun is installed on the turret. Mortars can use all types of 120mm mortar mines provided for by NATO standards, including guided ones. I must say that due to the peculiarities of the ballistics of the existing mines and some aspects of the "anatomy" of the mortar on the AMOS + CV90 bundle, the maximum firing range had to be reduced from thirteen to ten kilometers. At the beginning of the tests, the new twin mortars could produce a total of only 10-12 rounds per minute. The refinement of the automatic loader over time made it possible to bring this figure to 26 rounds per minute.
Perhaps the most difficult part of a mortarman's combat work is calculating the parameters of the shot, such as the elevation angle. The AMOS combat module includes computing equipment that allows for relatively quick aiming of mortars. Also, the computer can produce guidance when firing in motion at speeds up to 25-30 km / h. In this case, the effective firing range is reduced to five kilometers. But the main new feature of the self-propelled mortar, which the developers "boast", is preparation for firing on the move. In other words, all the necessary calculations and guidance of the weapon can be done in motion. This is followed by a short stop, a series of shots and the car continues to move. It is argued that the accuracy with this method of firing is not worse than when firing from a completely stationary position. Obviously, for such firing, the computer must "know" the coordinates of the target and the coordinates of the place from where the self-propelled gun will shoot. With the current widespread distribution of satellite navigation systems, this looks real.
As already mentioned, any NATO 120 mm mines can be used as ammunition for the AMOS system. High-explosive fragmentation ammunition provides reliable defeat of enemy manpower, unprotected and lightly armored vehicles. A direct hit on a heavier vehicle can cause serious damage, but this is the exception rather than the rule. In the future, it is possible to create other types of mortar mines, for example, thermobaric ones. However, so far only high-explosive fragmentation ammunition is used.
Finnish-Swedish cooperation in the creation of the AMOS mortar system ended with the fact that in the second half of the 2000s, a number of self-propelled mortars entered the armed forces of both countries. Finland in 2006 ordered 24 AMOS self-propelled guns, the total cost of which exceeded the figure of one hundred million US dollars. Sweden turned out to be "more economical" and a little later ordered only two dozen mortars. The Swedish order is interesting not only in quantity: the first two dozen AMOS are installed on the CV90 chassis, but in the future, the SEP platform, which is currently being developed, can become the "carrier" of the mortar tower.
For those customers who consider two mortars an overkill, a modification of the combat module called NEMO (NEw MOrtar - New Mortar) was created. NEMO, unlike AMOS, has only one barrel. The rest of the differences in the combat vehicle are somehow connected with this fact. Interestingly, the NEMO self-propelled mortar proved to be more popular and successful than the original AMOS. Apart from Finland and Sweden, only Poland has shown its interest in a double-barreled mortar, and even then, for several years now, it has not been able to decide on its intentions regarding the purchase of it. Several contracts have already been signed for the supply of NEMO. Saudi Arabia has ordered 36 NEMO modules, Slovenia wants two dozen self-propelled mortars, and the United Arab Emirates wants 12 towers. Moreover, Arabia will independently install NEMO towers on the chassis of floating armored personnel carriers, and the UAE - on patrol boats. A curious use for a mortar.
As you can see, AMOS and NEMO modules can be installed on different chassis. In particular, Poland is going to put them on KTO Rosomak armored personnel carriers. The developers of the mortars themselves claim that their towers can also be installed on the chassis of the British FV510 Warrior infantry fighting vehicle and even on the Russian BMP-3. For the installation of the tower with mortars, no special design changes are required. With such undemanding media requirements, AMOS and NEMO systems may have good prospects. Their future depends only on the wishes of potential customers.
