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A composite top hat to protect a World War I Australian submarine conning tower

News International-French

5 Sep 2014

Australian based advanced composite manufacturer and composites specialist, RPC Technologies, lent its expertise to develop a secure top hat to be placed over the open conning tower hatch as part of an initiative of the AE2 Commemorative Foundation.

For the first time in 100 years the World War I Australian submarine, HMAS AE2’s (the Silent ANZAC) conning tower hatch was opened in June 2014. The wreck is intact, sitting upright in 73 meters of water in the Sea of Marmara where it fell in battle on 30 April 1915. RPC Technologies undertook the work on a pro bono basis, with the design, specialist fabrication and manufacturing being undertaken at its Corio facility.

The ‘top hat’ (hatch), specially designed and manufactured by RPC in glass reinforced plastic (‘GRP’), fits over the open conning tower hatch to prevent unauthorised entry to the submarine. The hatch had to be strong, light and securable to prevent unauthorised entry. It also had to have exceptional anti-corrosion properties to contend with both the rigours and sensitivities of a marine environment at a depth of some 73 metres.

“Composite materials like GRP give us the ability to produce complex shapes to enable multiple components to be moulded into one part which also helps to save on weight and helps reduce manufacturing costs”, says RPC’s James Zegir.

There were also special design requirements to shape and provide slots within the new hatch to allow for normal water current flow and to provide unimpeded access for marine creatures.

John O’Brien coordinated the project on behalf of RPC, with their Technical Manager, James Zegir, designing the hatch that was ultimately crafted by RPC employees Floro Cabanban with support from Dave Byrnes and Bill Jones at the Corio facility.

RPC’s 40 years’ experience in advanced manufacturing for water infrastructure, passenger rail and the Australian defence industries were also drawn upon to develop a simple yet effective design.

The ‘Silent ANZAC’ project has been a collaboration of experts, all volunteers, drawn from Australia, USA and Turkey.

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