Introduction Into Commercial Service for Electronic Controls Used on Large Turbofan Engines

Hamilton Standard electronic engine controls for large Pratt & Whitney turbofan engines have completed their first two years of commercial airline service. Their successful introduction has demonstrated the feasibility of using engine mounted digital electronics to: (1) control and improve the performance of a modern aircraft engine and (2) to enhance integration of engine and aircraft systems. This paper summarizes the effect of this equipment on the customer and examines the factors which have contributed to its success, including developmental history, design criteria, reliability considerations and maintenance concepts. The advantages of a digital electronic control as an engine component are discussed along with unique considerations arising from introduction of this new product into the airline fleets.