In the spring of 1942, the British inventor Geoffrey Pyke came up with the innovative idea of producing tracked vehicles with the capability to move across the winter landscape of Europe and attack German installations. A plan was initiated by Allied authorities to develop such a vehicle, and targets were identified in Norway, northern Italy and Romania. The vehicle was dubbed the Weasel. Only the Norwegian installation was ever seriously considered in the final planning stages, and it was dubbed Operation Plough. The Germans used the hydro-facilities in occupied Norway to create heavy water for their atomic weapons program. During Operation Plough, paratroopers with skills in demolition and winter warfare were to be airdropped into central Norway along with their Weasels. Their goal was to destroy these facilities or at least to disrupt their heavy water production. The timeframe for the assault was set for late December of 1942. It was a single purpose mission because there would be little chance for the paratroopers to withdraw to neutral Sweden once their objective was met, and whatever survivors, who were not executed by the Germans, would spend the remainder of the war as prisoners. The American officer put in charge of forming the unit was Robert T. Frederick, and he chose the name First Special Service Force. Initially, the plan was to use British, Norwegian, Canadian and American volunteers, but in the end the British and Norwegian governments declined to participate. The Force was divided into a combat echelon (three regiments) composed of Canadian and American soldiers and a service battalion of primarily American members. The men were given the nickname Braves, and the chosen insignia were crossed arrows and a spearhead in keeping with the indigenous theme.