DUAL CENTRIFUGAL COMPRESSORS: THE HELICOPTER SOLUTION TO SAND AND ICE INGESTION

Aircraft operation in severe environmental conditions places extraordinary demands on engine structural design. Engines periodically ingest hail, ice, birds, sand, and other foreign objects during normal flight operation. Damage resulting from foreign object ingestion can render an engine inoperable, which ultimately leads to increased operator cost. Fans and compressors are inherently vulnerable to impact from foreign objects. The use of lightweight materials and high rotational speeds in advanced engines dictates the need for rugged, damage-tolerant compressor components. The helicopter operating environment is especially severe and places unique requirements on engine compressors, in addition, helicopter engines are often quite small, increasing the probability that foreign object impact will cause severe damage. The inherent damage tolerance and proven performance of centrifugal compressors makes effective aircraft operation in adverse environmental conditions a reality. As a result, helicopter engines with centrifugal compressors offer a significant reduction in operator cost through increased reliability, operational availability, and reduced maintenance.