Thought provided by Colin Jolly, please refer to the the picture named 'Dads Hydraulics' in the picture gallery: One of the great things during meetings with Les was his ongoing interest in the technologies on which his career was based. One example was the prototype special grout mixer developed for the military, shown in the photograph. The grout was used to repair bomb craters in airport runways, after the Falklands runway had been almost closed to aircraft. I had tested the vehicle’s ability to produce (without seizing up) very rapidly-setting grout repairs to craters created on wartime runways in the New Forest. Only twenty years later did I discover that the hydraulic oil drive systems for the vehicle had been designed and commissioned by Les.