 The German supply of aviation fuels was largely based on the hydrogenation of coal, due to their limited supplies of natural crude oil.At the outbreak of the war, Germany already had seven destructive hydrogenation plants in operation, with a total installed capacity of 1,400,000 t/year of oil.At the start of the war the Luftwaffe standardized on 87 octane aviation gasoline, called "B4", made from leaded hydro-petrol extracted from brown coal.