Martin Wickham writes:
In the 1990s, mines dug into the unmetalled roads leading up to isolated farms in what was Southern Rhodesia created widespread terror and had almost brought the country’s agriculture to a standstill. South Africa had developed mine protection technology which steadily improved as the threat extended into South West Africa, and by then it was considered the World leader.
However, international isolation resulting from apartheid meant that South Africa had very limited experience of military sales to overseas markets. David Brittain, then Managing Director of Alvis Vehicles Ltd saw the symbiosis of Alvis accruing the technology whilst giving South Africa openings and expertise in military exports.
On the day that Nelson Mandela was elected President of that country, 10 May 1994, Alvis announced an agreement with Mechem Industries along such lines. The groundwork had been done in the preceding year or more, when it became apparent that international opprobrium was declining together with the apartheid regime.
Acorn, like other South African mine protected vehicles, used the running gear stripped from a Unimog chassis and installed in a purpose built welded hull. Unimog (part of the Mercedes organisation) was well established as an off-road vehicle, and had been imported from Germany over many years, or manufactured under licence. The Acorn was a prototype hull embodying the same running gear, where some mine protection was traded against low profile and high performance as a scout vehicle.
Alvis trialled the prototype and sought to develop it to meet a requirement issued by MoD in the late 1990s. The principal of using standard Unimog running gear was retained, because of the export sales potential. Running gear spares would be available almost anywhere in the World, and could be ordered directly from the Mercedes group. Acorn however was based on an obsolete Unimog model, so the new design was necessarily updated, based on the latest information provided from Mercedes.
Mercedes would release information only about changes planned to hit the market 18 months ahead, because that was all that was generally necessary for suppliers making very minor adaptations. However, this major MoD contract had a lead time of several years, covering design, development, service and reliability trials etc. An armoured hull requiring very careful design, especially around maintenance access points, would be incompatible with an 18 month notification of, for example, a revised oil filter position. Following several enforced compromises and intransigence from Mercedes, Acorn was transformed into a design that failed to beat the competition into British army Service.
The Acorn developed into the Scarab, the brochure below from the Alvis Vickers website
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