The Denel Land Systems G6 self-propelled howitzer remains one of the most accurate long-range 155 mm guns in the world.
In 1987, during the last phase of the South African War in Angola, three pre-production G6 self-propelled howitzers entered the battle zone that was the Operational Area of South East Angola.
The ability of the gun to be set up (laid) once and then be repositioned kilometres away within minutes made it a very difficult target to pinpoint. This was achieved by utilizing an onboard inertial navigation system (INS). The vehicle’s position was determined by map reading and supplemented by an inertial gyroscopic system as well as a distance transmitting unit (DTU) to accurately determine the distance travelled in any direction. The accuracy of this system can only be achieved by maintaining a constant tyre rolling radius at specific tyre pressure settings, determined by the terrain being traversed. The tyre pressure control system (CTIS) is thus called on to monitor and correct individual tyre pressures on a continues basis.
The laying and the navigation system fitted to the first G6 prototypes were innovative and industry-leading for a number of years until the availability of the now commonly used global positioning system (GPS) technology. Nowadays an inertial-based navigation system with DTU and GPS positional corrections are used, thus improving accuracy while compensating for gyroscopic drift.
Thus, positioning and laying the gun can be achieved in a matter of seconds and the first round on target can be affected in less than a minute. The backup plan is to follow the old school sighting pole, compass and cartography route for aiming. Interestingly, when the mentioned G6 troop withdrew from Angola in late 1987, they took two days to travel 130 km over bush and unprepared terrain without suffering any tyre damage.
The importance of having the correct tyre pressures for the terrain being traversed was thus proved beyond doubt. The G6 with its six wheel configuration weighs in at 39 tons and when fully loaded, can exceed 45 tons with a tarmac top speed of 90 km/h. Individual tyre pressures are continually monitored and adjusted while in motion for both stability and safety reasons. Improved tyre and driveline life as well as crew comfort on long distance trips are also important features and benefits.
The G6 weapon system is now 33 years old with various gun and munition upgrades implemented over the years. The requirement to address vehicle platform obsolescence risks was identified in 2014 by the South African National Defence Force (SANDF) and Armscor. The consequent risk mitigation Project Mohale called for the following:
• The redevelopment and supply of obsolete component alternatives, including the testing and qualification of these proposed alternatives.
• The fitment of proposed alternatives onto a fleet leader platform supplied by the client.
• The logistic development of the components.
The central tyre pressure control system was identified as a supply risk due to the obsolesce of various subsystems and components. Denel OMC (now Vehicle Systems) evaluated various options, finally selecting Mavtech Technologies to participate and offer a fit form and function replacement solution. Mavtech Technologies installed their Tyre Pressure Control System (also known as a Central Tyre Inflation System – CTIS), to the SANDF fleet leader vehicle, which was subjected to trials and tests both at the Gerotek testing facility, as well as the Alkantpan test range. The Mavtech system was approved and qualified and accepted as a suitable replacement by both Armscor and the SANDF.
Due to the successful development and acceptance of the system, the South African National Defence Force has issued a request for the upgrade of a further 14 platforms of their existing fleet.
Mavtech’s technical team are currently together with Denel Vehicle Systems undertaking the removal and replacement of the obsolete systems, which according to Denel will be completed mid-2021.
Denis Mavrokefalos, CEO of Mavtech Technologies, said the South African Army’s show of faith in the local industry with this upgrade, opens the door for other operators, for example the United Arab Emirates and Oman who field large numbers of G6 howitzers.
“Mavtech Technologies, with over twenty years of experience in the field of Tyre Pressure Control Systems (CTIS), are proud to be part of the Muhali project. Our team of engineers and technical field service representatives stand ready to assist new and existing customers with any vehicle specific design or solution which may be required anywhere and at short notice,” Mavrokefalos said.