in order to determine the empty weight and center of gravity of an aircraft at the time of certification an aircraft manufacturer may use the weight of to percent and apply the average to all other aircraft

In an engine working on the diesel cycle the ratios of the weights of air and fuel supplied is 50: 1. the temperature of air at the beginning of the compression is 60 °c and the compression ratio used is 14: 1. what is the ideal efficiency of the engine. calorific value of fuel used is 42000 kj/kg. assume c, = 1.004 kj/kg k and c 0.717 kj/kg k for air