DYNAMIC CHARACTERISTICS OF AN ASSEMBLY OF PROP-FAN BLADES.
The renewed interest in propeller propulsion is based on large reductions expected in fuel burned and direct operating costs compared to advance turbofan propulsion. Current predictions indicate that a prop-fan (Advanced Propeller) powered 120-passenger aircraft will burn 20% less fuel than a similar turbofan powered aircraft. Potentially greater benefits are predicted with counter-rotating prop fans. Test results are presented including both steady deformations and vibratory frequencies and mode shapes of the prop fan in vacuum centrifugal environment. Several unique measurement techniques were used during the program including determination of the steady-state deformations by measuring the angular deflections of a laser beam reflected from mirrors bonded to the blades. 9 refs.