Twelve thousand T56 turboprop engines have been delivered to 49 countries for use in commercial and military aircraft. The Air Force and Navy are sponsoring a program to develop a cost effective T56 derivative engine with 10 1/2% fuel consumption improvement and 24% power increase. These improvements are being achieved by utilizing only previously demonstrated component technology, while retaining 90% parts commonality with the current production T56 engine. Primary changes to the engine are in the compressor and turbine. Existing T56 engines can be upgraded to the new configuration via retrofit kits installed during normal engine overhaul.