The competition for ever faster aircraft in World War II pushed the development of internal combustion engine aircraft and their propellers to their theoretical and mechanical limits of performance.  The solution to providing more power was found in the axial and centrifugal flow turbine engines.  Ken Weiler will discuss the transition from the final development of the internal combustion engines and the aircraft equipped with them, to the aircraft flying with the early, primitive turbine engines.  We'll look at the early jet and rocket-powered aircraft of the major combatants.