MODEL RELEASED. Wind tunnel construction. Engineer working on the flow conveyors for Milan Polytechnic's wind tunnel. The bank of fans can be seen behind the conveyors. Construction of the tunnel began in 1998 and the wind tunnel started operating in 2002. The fans can produce wind speeds of up to 58 kilometres per hour. The wind tunnel has been designed to allow complex testing of civil and aeronautical models. Photographed at Milan Polytechnic's aerospace engineering department, Italy.