CASR

Canadian
American
Strategic
Review

Blast  Resistant  Vehicles  –  CF Armoured Fighting Vehicles  –  October 2006 Blast-Resistant Vehicles For Beginners  —  "Scatterlings ..." Tracing the Origins of 'Mine-' and 'Blast-Resistant' Vehicles Stephen Priestley, Researcher, Canadian American Strategic Review (CASR) The downsides of  flat-bottomed armoured vehicles are obvious where landmines or roadside improvised explosive devices are encountered. If  IEDs or mines might be thwarted  by shaping the bottom of the vehicles to deflect the blast wave, why has this approach taken so long to gain acceptance? Political appearances are one reason. The origin of mine-resistant vehicles is firmly connected with apartheid in South Africa and few western armies were eager to be associated with that time.[1] "... We are Scatterlings of Africa ..."  –  The  Hard Cases  from a Troubled Land The CF's  RG-31 Nyala  Armoured Patrol Vehicles are made in South Africa. The APVs are part of a complex lineage of  blast-resistant  vehicles  developed on that troubled continent. That line began in Rhodesia (now Zimbabwe) with a series of  highly bizarre, mine-resist- ant types set on commercial chassis (eg: VW-based Leopard, above, and Pookie). Those early vehicles were mostly built as mine-detector vehicles but they showed the way with high ground-clearance and monocoque crew compartments with a V- shaped bottom. The next step was incorporating that structure into other vehicles. The Crocodile troop carrier was based on a 5t truck. Other vehicles were set on Landrover 4x4 chassis – such as the Kudu (right) and Rhino patrol vehicles. These vehicles were simply a V-bottomed crew cab perched on top of  the Landrover chassis. Crude as they were, these knocked-together vehicles were the first truly mine-resistant and therefore blast-resistant armoured personnel carriers. As conversions of existing types,  Rhodesian mine- / blast-resistant vehicles were quick to construct and made use of readily-available components. This did not go unnoticed in neighbouring South Africa facing its own anti-apartheid 'bush war'. The threats were the same: landmine blasts from below and AK-47 rifle bullets. [2] 'Body-on-Frame' Construction  –  the South Africans  Follow a  Rhodesian  Lead The first South African blast-resistant vehicles were a series of Kwêvoël [3] trucks (Samil-built Deutz 4x4s and 6x6s with armoured cabs) followed by a fully armoured personnel carrier derivative – Hippo. Buffel, a more sophisticated armoured carrier type followed.  All consisted of V-bottom armour compartments over truck frames. Buffel took the concept further, stripping away all unnecessary components. The driver station was reduced to a skinny cab[4], the engine left  largely exposed. Even the  top of  the  personnel compartment wasn't covered at first.  This was a concession to weight-saving but also a recog- nition of  Buffel top-heaviness. Such compromises showed the problem with body-on-chassis. The Buffel was a huge improvement over a straightforward truck adaptation – like the Hippo  –  both design and construction were simple, and maintenance access to the exposed drivegear could not be easier.  However, a body-on-frame mine-resistant vehicle design pays a penalty for the convenience of its construction –  that frame is a weak link. The angles and gussets of  the frame  create 'blast traps' that can topple the vehicle. A mild-steel frame, itself, is also excessively vulnerable to blast damage. A frame also means that the body must  be higher  –  exacerbating top-heaviness. [5] "Shell Game"  –  South African  Monocoque Construction  for  Mine Resistance The answer, as  with  automobiles, was to combine the frame with  the body  –  the armoured  monocoque shell is strong to support drivetrain components and to resist blast. All suspension parts, axles, and  drive- shafts are external. Engine, transfer case, and transmission are protect- ed  within the armour hull.  In other words, drivetrain  components  will be sacrificed  to the blast of  a mine but,  more often  than not,  the  hull remains intact.  Afterwards, tough suspension parts can simply be bolted back on. South Africa's  first  monocoque blast- resistant vehicle was the Casspir APC. Originally designed for police work [6], the Casspir used Unimog running gear for commonality with SADF trucks and the earlier Buffel APCs.  So, a question arises:  if  mine-resistant hulls make for perfect blast-resistant vehicles, why bother with other forms of armoured vehicle? [1] As police vehicles, the Casspirs, in particular, were associated with apartheid. [2] The hull sides are designed to stop grenade fragments and 7.62 x 39mm rounds (not  to be confused with Russian 7.62 x 53mm, equivalent to NATO  7.62 × 51mm). [3] There were several early  South African  vehicles very similar to the Rhodesian conversions – Hyena, Wolf, and Ribbok (an antelope). Kwêvoël is Afrikaans for a turaco (Corythaixoides). Buffel is Afrikaans for the Cape buffalo (Syncerus Caffer) [4] The narrow cab has a side access door and an emergency roof hatch (for use if the Buffel rolls onto its side). As shown, early-model Buffels were left-hand drives. The later Samil 20-chassised Bulldogs had right-hand drive and a covered engine. [5] The extra floor height might even make the rear compartment safer (however, to compensate for weight, the Buffel's rear compartment had to be left uncovered). In any case, blast bent the frame's mild-steel construction resulting in 'mobility kills'. [6] The concept originated with the Council for Scientific and  Industrial Research, Casspir is an anagram of CSIR and SAP (South African Police, the first client). The Casspir was built by TFM at Olifantfontein but corporate name changes become a trial: the Olifant Manufacturing Company becomes in turn Reumech OMC, Vickers OMC, Alvis OMC, and  finally BAE's  Land Systems OMC  (makers of the Nyala). Next in this In Detail Review –  CF  RG-31 Nyala APVs: Buy More, Build Better