Hirtenberger MDAS - Digital aiming device for 81mm mortars

Hirtenberger Defense Systems (HDS) used the Mortar Systems Conference (Bristol, UK) on March 10th and 11th, 2020 to present the Mortar Digital Aiming Solution (MDAS), a digital aiming tool for 81mm mortars. The setting up and aiming (aiming) of bipod mortars can be carried out using this system independently of directional circles or periscopes and even without connections to Global Navigation Satellite Systems (GNSS).

The modern battlefield requires rapid and, above all, precise deployment of the respective weapon systems in order to be able to combat quickly moving targets or to only expose one's own weapon systems to enemy counterfire for a short time during operation.

Hirtenberger has therefore set itself the goal of shortening the mortar-related sensor-to-shooter cycle by digitizing the dismounted mortar systems and thus preparing them for use on the future battlefield. In this case, “digitalization” means integrating the weapon system into a battle management system and mapping the mortar in digital space, which is currently only possible for vehicle-based systems.

After the GRAM presented in 2018 for the 60 mm command mortar, the Austrian system house for mortar systems with MDAS now also offers an operational system for 81 mm bipod mortars. MDAS is not subject to ITAR regulations and, according to Carsten Barth, CEO HDS, is also able to withstand the recoil forces that occur when using 120 mm mortars. Therefore, MDAS will also become available for 120 mm mortars in the near future.

MDAS

The Mortar Digital Aiming Solution weighs less than seven kilograms and consists of two hardware components that, depending on the version, communicate either via a cable connection or wirelessly and can be transported protected in a transport box. The two system components are:

• A navigation system-independent, gyroscope-based sensor package including a battery unit (recognizable in the picture as a black box on the mortar tube), which can be attached to any 81 mortar systems in use using a tube clamp. The system is shock resistant, so it does not have to be removed from the barrel even when firing at maximum charge or when changing position. The battery charge is sufficient to ensure continuous operation of the MDAS for more than six hours.
• A display, which is attached to the mortar in place of a periscope and shows the orientation of the weapon system.

With these components alone, MDAS enables digital and independent straightening.
The system can also be integrated into a fire control system. For this use, a fire control computer (laptop or smart device) with fire control software installed is required. Computers and software can be freely chosen by the user, regardless of manufacturer.

All the data required for fire control (target reports, position data, etc.) can either be taken over automatically from a navigation system or entered manually into the MDAS via the computer. In this network, MDAS enables the integration of the mortar weapon in digital space.

MDAS is shock resistant and can remain attached to the mortar even while firing. Here shot with the 6th charge of an 81mm mortar. (Video: Hirtenberger)

functionality

The video explains how it works and the individual steps involved.

1. After reaching the firing position, the squad begins to set up the weapon system and calibrate the MDAS in parallel. As is already known from target location devices, the calibration can take up to two minutes and is carried out automatically by the system. Once the system is calibrated, it maintains it. It is therefore possible for a switched on and calibrated system to change position (firing position) several times without restarting the calibration process. This saves the time of calibration (video) when moving to the new firing position. According to Carsten Barth, the accuracy of the system is ≤ 10 mil secLat. (after 120 seconds calibration), ≤ 3 mil secLat. (after 180 seconds calibration) or ≤ 2 mil secLat. (after 240 seconds calibration).
2. Attachment of the MDAS to the weapon system using attachment points attached to the barrel and the display.
3. Calculation of the orientation of the weapon system in terms of elevation and lateral orientation by MDAS.
4. Aiming the mortar at the target.
   1. The fire control computer determines the necessary change in position of the mortar barrel in order to align it with the target.
   2. The necessary corrections are shown on the display and the mortar, depending on the system, is aimed at the target by the gunner and loader. The troop leader monitors this by means of a display on his PDA. The mortar is thus ready to fire.
5. Correction commands run analogous to step 4.2.

The video shows the individual steps involved in moving into an unprepared firing position with a squad of three equipped with MDAS. (Video: Hirtenberger)

Conclusion

According to the manufacturer, MDAS is ready for series production and is currently being tested for use in a Central European country. The concept behind MDAS offers several advantages:

1. It works independently of the weapon system and can therefore increase the combat effectiveness of mortar systems in use as a retrofit and integrate them into the battle management systems used by the armed forces. This simplifies both the management and the use of the systems.
2. Furthermore, the digitization enables a significantly faster transmission of the target data than by radio. Depending on the stability of the data connection, transmission errors (wrong understanding) are also eliminated. This allows for faster impact on target.
3. MDAS relieves the squad. This applies to both the quality and quantity of the tasks. Setting up the weapon systems can be done with less effort and the ammunition shooter setting the straightening rods does not have to expose himself in advance. Aiming with a digital display is easier to learn and also easier to carry out in stressful situations (battle) than is the case with aiming rods/collimator and periscope. As a result, training is easier and faster, and the squad size required for firing can be lower. The freed-up personnel, who are still required to transport the weapon system for combat purposes, can thus be used for additional security tasks.
4. The possibility of using the MDAS independently of the navigation system also allows it to be used in a scenario determined by electronic combat.
5. MDAS allows the mortar, where necessary and appropriate, to continue to be used in the tried and tested manner with periscope and straightening rods.

Even if the mortar weapon system is a “simple” weapon, several well-trained soldiers are necessary to be able to use this weapon system effectively, precisely and quickly. Intensive training is necessary to ensure that the interaction between observers, fire control and the individual soldiers of the mortar squad functions flawlessly, even in stressful situations inherent in combat. The time required for this is not always available, especially in armed forces that rely on conscripts or only provide mortar soldiers with a secondary function. Individual step sequences, which are carried out using hardware or software, can significantly reduce the burden on soldiers.

However, it is important that the functioning of the weapon system should not be impaired in emergency situations - failure of a support system due to malfunction, wear and tear, electronic warfare conditions. If the worst comes to the worst, the weapon system must have redundancies so that it can also be used “classically” if necessary.

MDAS has the potential to increase the operational value of classic bipod mortars by improving the leadership capability and operational speed of the weapon systems, while at the same time reducing the necessary training and personnel costs of the mortar teams.

It is up to the respective user how they want to use the freed up capacity. However, it must be borne in mind that the weight of the weapon system is not reduced by MDAS; the full squad strength is still required to transport the weapon system (change of position, etc.). Once in position, a mortar could be operated comparatively quickly by just one soldier in an emergency, for example an attack on the firing position (mechanical alignment of the mortar to the guidelines specified by the system and the preparation and loading of the ammunition), all of them Other squad soldiers could lead the infantry fire fight.

Waldemar Geiger