Casspir APC
The Casspir is an unusual vehicle, being in service in much the same form not only with several South African Police forces but also with the South African National Defence Force in a virtually identical form.
Built originally by TFM (Ply) Limited, the Casspir was originally based on a Bedford heavy commercial truck chassis but this was gradually modified and strengthened so that the Casspir can be taken as an original design.
The Casspir resembles an armoured truck with the armour extending to specially-shaped under-hull plates intended to reduce the effects of land mines and Casspir have repeatedly demonstrated that they can indeed survive heavy mine detonations; some have been specially equipped for detecting and clearing mines from roads in remote areas.
The first Casspir appeared in 1981. Since then over 2,500 have been produced and many have been rebuilt to extend their service lives, as production has now ceased.
The cab roof has provision for a weapon station, usually a single 7.62 mm MG but police vehicles may have all manner of anti-riot weapons, including a rapid-firing rubber bullet dispenser.
The troops (or police) are seated on outward-facing bench seats down the centre of the rear compartment and are provided with vision blocks and firing ports (police versions usually have larger vision blocks covered by grills). Entry to the rather high off the ground compartment is via a door in the rear – large roof hatches are provided.
Also produced is a Casspir ambulance, and three ‘specials’. One of these is the Duiker 5000-litre fuel tanker with the tank replacing the troop compartment.
The Blesbock is an armoured load carrier with a cargo body capable of carrying 5 tonnes of supplies – a water tank may form part of the load.
The Gemsbock is a recovery vehicle.
There have been three main models of the Casspir, the Mk 1, Mk II and Mk III, all of which have incorporated improvements as a result of operational experience. Wherever possible standard commercial components are used in the construction of the Casspir family of vehicles.
Update South African [Denel Mechem] Casspir – In service with 10 African, South American, and Asian nations, the blast-protected Casspir is at the heart of a wide family of vehicles. Those include APC, Ambulance, Blesbok Freighter/Weapons Platform, Duiker 5000-liter Tanker and Artillery Fire Control, Fire Support Team, 15-ton capacity Gemsbok Recovery, Mechem Mine-clearing, Mechem Explosives and Drug Detection System Mine Sensor, Mechem Vehicular Array Mine Detection System, Plofadder Mine-clearing System, Riot Control, and Mechem Low-Profile/ short-wheelbase vehicles.
Specification Crew: 2 Seating: 10 Weight: (combat) 12,580 kg Length: 6.87 m Width: 2.5m Height: 2.85 m Ground clearance: 0.41m Track: 2.07m Max speed: (road) 90km/h Fuel capacity: 220 litres Range: 850 km Fording: 1 m Vertical obstacle: 0.5 m Engine: ADE 352T diesel Power output: 170 hp Suspension: leaf spring Armament: 1 to 3 7.62 mm MG Variants: Blesbock, Duiker, Gemsbock
Casspir for Angola – 2014+
Angola has ordered 45 Casspir armoured vehicles from Denel Land Systems (DLS). The order is for the Casspir NG 2000B, which offers protecton to B7 and STANAG 4569 levels. It comprises 30 armoured personnel carriers (APCs) with light turrets for machine guns, four fire-support vehicles able to mount either a twin 23 mm cannon or a recoilless rifle, two command vehicles, two wide-body ambulances, two medium recovery vehicles, three logistic variants, one diesel tanker and one water tanker, as well as a spares package and initial training for drivers and mechanics.
Angola is believed to have selected the B-model because it uses a South African Powerstar 4×4 1729VX Model Euro 2 drivetrain that does not have electronic engine control interfaces, making it more reliable in African operational conditions. The `new generation’ Casspir NG 2000 can also be supplied with Euro 3- or 4-compliant drivetrains, and has been supplied with a Chinese drivetrain.
DLS has sold Casspir NG 2000 APCs to Benin (10) and to the United Nations (15) for use in Somalia, Sudan and other theatres.
Angola’s decision to buy Casspirs could be motivated by plans to participate in peace-support operations. Its forces have been conspicuously absent in this role, but Luanda appears to be looking to increase its regional influence, which will require it to participate in such missions. However, much of the Angolan Army’s equipment is either unsuitable for peacekeeping operations or extremely old and of doubtful serviceability.
Mamba APC
At first sight the Mamba APC resembles a somewhat bulky but conventional personnel carrier but it was developed not only as an APC but as a mine protected vehicle for operations in areas where land mines are likely to be encountered. It was developed following along series of mine-proofed vehicles specifically produced to counter the mine warfare conditions once prevalent along the South African borders and in the former Rhodesia.
The Mamba originally produced by Reumech Sandock, thus has an armoured underside with sloped plates intended to direct the worst of a mine blast away from the vehicle. The chassis itself is based around the use of Unimog components and the Mamba thus has a remarkable cross-country performance.
The steel upper hull can be armoured virtually according to requirements but is usually proof against small arms fire and ammunition splinters. The interior has the commander and driver seated side by side and up to nine troops seated in close proximity in the rear; entry to all position is via a single door at the rear or via roof hatches.
The commander has a roof hatch over which a MG can be mounted, if required, All occupants are provided with bullet-proof windows and the entire roof can be opened up when necessary The rear area can be readily configured to form an armoured ambulance or a command vehicle.
Other body types include a flatbed body for load carrying, to mount light weapons, or to accommodate a recovery hamper. It has been proposed that the Mamba could be fitted out as a VIP protected transport. The Mamba has been acquired by the South African National Defence Force and several other countries.
Specification Crew: 2 Seating: 9 Weight: (combat) 6,800 kg Length: 5.46m Width: 2.205m Height: 2.495m Ground clearance: 0.4 m Track: 1.79m Max speed:(road)102km/h Fuel capacity: 200 litres Range: 900 km Fording: 1 m Vertical obstacle: 0.4m Engine: Mercedes-Benz OM352 diesel Power output: 123 hp Suspension: coil spring Armament: 1 x7.62 mm MG (if fitted)
Enter the MRAP
Mines and explosive devices are hardly new to warfare. Massive mine fields were emplaced in every theatre during World War II and the Korean War while locally manufactured booby-traps were a common hazard faced by patrols in the jungles and rice paddies of Vietnam. Generally these were un-attended and passive with their detonation triggered by the action of the vehicle or soldier that happened upon them. They were unexpected and deadly with adverse affects on troop morale which caused them to move more cautiously. They also were extensively used in Rhodesia and against the South African Defence Forces (SADF) in its incursions into Angola, Namibia and Zambia in the Border Wars from 1966 to 1990. In fact, the use of mines was adopted as the principle tactic of the People’s Liberation Army of Namibia (PLAN) against the SADF. Mines came to define the conflict.
This tactical aspect of the South African conflict received little international attention by the major armies but it forecast the dominating role that mines and IEDs would take on in coming conflicts. It also offered some ready-made solutions for protecting against these threats though SADF’s development and fielding of armoured V-hull vehicles. South African developers, including the company OMC that perfected the monocoque hull, developed designs that resisted the blast of an explosion under the vehicle belly or wheels. Combining an angled belly, unencumbered hull form, increased ground clearance and breakaway suspension components, its designers were able to provide a series of vehicles that reliably protected the vehicle’s occupants. A key part of the design’s effectiveness was in directing the blast forces away from the vehicle’s welded armoured crew compartment (which became known as its `citadel’). The initial Casspir Mine Protected Vehicle (MPV) design was introduced in 1980 and remains in service with over 22 nations. The design concept was further perfected by TFM Industries as Mamba and later expanded by OMC as the RG-31 Nyala MPV. The value of these mine protected vehicles was well recognised and they were acquired and employed in various United Nations peacekeeping operations.
The magnitude of the IED threat in Afghanistan and Iraq and the inadequacy of up-armouring efforts became evident and a team from the US travelled to South Africa where it viewed a Casspir successfully cross a live mine field.
V-Shaping
Two approaches to V-shaping – the Casspir and the Mamba armoured personnel carriers.
Included Angle of the V-Shaping on Certain Rhodesian Armoured Vehicles.
To improve occupant survivability by way of reducing acceleration to the occupants, much of the effort has centred on the deflection of the blast wave away from the vehicle. And so, most modern armoured vehicles have V-shaped hulls to achieve this.
Blast defection through V-shaping was developed in the early 1970s by the South Africans. During this time, they modified a WWII-vintage Swedish SKPF M/42 APC by integrating a special-shaped steel capsule with a 43° V-shaped bottom (Hoffman et al. 1991). Generally speaking, geometry dictates that the smaller the included angle of the V-shaping, the more the blast energy will be deflected, and therefore, a lower vertical impulse will be delivered to the vehicle. However, the height of the vehicle will also increase with the potential to make handling and stability more problematic. Picture above lists some of the included angles of vehicles used by the Rhodesians. Notably, the Camel was named so due to its `ungainly’ appearance.
For vehicles where it is simply not possible to introduce a V-shape to the hull due to height and handling problems that may arise, it is possible to introduce a `double V’-shape (or essentially a `W’-shape). With this concept, instead of the blast being solely directed to the outside of the vehicle, a double V-shaped arrangement means that some of the blast is directed into the centre of the vehicle (Lee 2013). The blast is then spread fore and aft along the vehicle’s central axis using a suitably reinforced `duct’ that is concave downward. The deformation of the internal angled parts leads to a downward `pull’ on the central concave part thereby countering some of the upward impulse from the blast. Therefore, this provides a route to provide some meaningful blast protection in vehicles that would otherwise not be able accommodate a full `V’-shape.
A slight modification to this concept is the structural blast chimney method where a small (approximately laptop-sized) chimney is integrated into the centre of the vehicle (Tunis and Kendall 2013). This chimney provides a vent for the blast and therefore minimises the upward acceleration of the vehicle.
Different concepts for AFV hull design showing the pathways taken by a blast wave. (a) Flat bottom, (b) ‘V’ shaped, (c) Blast chimney concept.
General Techniques for Mine Protection
Other techniques for increasing the survivability in armoured vehicles can include using `breakable’ wheel axles so that the blast is not trapped by the wheel structure, energy-absorbing materials to accommodate the blast-wave energy and sufficient spacing from the blast to reduce the energy density of the waves in contact with the structure. The Buffel (a South African troop carrier) used some of these techniques.
As long as the occupants are sufficiently strapped down, and there are no loose projectiles to fly around the cabin, a principal factor to consider is the acceleration to the occupant. This is why it is often expedient to `insulate’ the individual from fast-deforming structures such as floor plates. However, where the occupant is subject to acceleration (due to the upward movement of the vehicle), or where the occupant is in direct contact with an accelerating structure such as a floor plate, then serious injury can occur.
Protection measures employed in an AFV.
roll over (or be shunted sideways) when being subjected to a blast wave. Angled hulls are also advantageous from a ballistic point of view. Having a decent amount of armour is obviously going to help survivability. The sides of hulls are particularly vulnerable to attack from IED fragments, explosively formed projectiles, shaped-charge jets and high-explosive shell fragments and, of course, bullets. It is also necessary to add a spall shield. These are generally constructed from glass fibre-reinforced plastic or ultra-high-molecular-weight polyethylene composite materials. Their advantage is that during a high-velocity attack, the diameter of the cone of fragments that is produced will be reduced. This leads to less lethality and greater survivability of a crew. The reinforcement of the welds is also crucial to ensure that the vehicle does not suffer structural failure during blast loading. Welds are often the weak point in a structure, and therefore, good quality control needs to be maintained.
A typical schematic of protection measures that are usually employed by an AFV is shown in pictures above.
In the same fashion that the V-shaping leads to an increased deflection prospect for blast-wave energy, having angled hull leads provide that advantage from a side-on blast. This can reduce the propensity of the vehicle to Additionally, it is beneficial to keep the occupant away from any dynamically deforming part – such as a floor plate. During a blast, the floor plate can be subjected to high accelerations that can lead to serious injury – particularly in the lower leg. Therefore, suspended seats and foot rests are used for this purpose.
