Germany is developing a new modernisation of the Leopard 2 tank

The German army has signed a number of contracts to develop a new artillery unit and power plant for the prospective modernisation of the Leopard 2 main battle tank.
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The Bundeswehr has commissioned KNDS Deutschland, Rheinmetall and Hensoldt to conduct technical research to create a more powerful tank engine, several types of 130 mm ammunition, a new weapons control system and protection systems for the Leopard 2. According to Hartpunkt, these developments will be an interim solution before the transition to the advanced MGCS tank.
The upgraded version of the Leopard 2 is expected to have improved performance in response to current threats and will have a service life of at least 25 years.
Rheinmetall has started developing three types of 130 mm ammunition for the new Rh-130 L/52 gun. The first to be produced will be the DM13 projectile required for testing. Later, the DM11 multipurpose high-explosive fragmentation munition with programmable detonation and the DM23 armour-piercing sub-calibre will be developed. Due to the large size of the new shells (1.3 m long and over 30 kg), all future models of tanks with the Rh-130 gun will be equipped with an automatic loading device and a new turret.

The Leopard 2A-RC prototype. Illustration: Hartpunkt
Two other studies, handed over to Hensoldt and KNDS Germany, relate to the development of a weapons control system. It will include automatic calibration of the gun to compensate for the effects of barrel heating from sunlight and firing.
In addition, KNDS Germany is developing an alternative OLYMP engine that will replace the MTU units. The new power unit will be supplied by Liebherr. It will have a modular design, including an internal combustion engine, manual transmission, cooling system, air filters and exhaust system.
The protection of the updated Leopard 2 will be enhanced by the integration of Hensoldt's MUSS system. It includes four sensors with missile and laser warning, an on-board computer, an infrared jamming system and smoke mortars capable of countering ATGMs.
Source: Hartpunkt