CIVIL HELICOPTER PROPULSION SYSTEM RELIABILITY AND ENGINE MONITORING TECHNOLOGY ASSESSMENTS

The operating cost of a helicopter is relatively high in comparison with that of other forms of transportation. If helicopters are to become truly competitive, this disadvantage will have to be reduced. Maintenance is the largest single direct operating cost item, with the propulsion system having the greatest maintenance requirements. This study was undertaken to determine how future NASA research efforts can be most effectively focused so as to reduce propulsion related operating costs through improved reliability, maintainability, and engine condition monitoring. It is concluded that the greatest single cost improvement would be the elimination of scheduled engine maintenance by means of a true "on-condition" engine maintenance concept. For the civil helicopter scenario, this will require research to develop the algorithms, procedures, and equipment necessary to make such a concept safe and practical.