Rolls-Royce said the Series 3.5 upgrade kits for the T56 engines have been delivered to the Air Force for installation and testing is to begin soon.
"We recognize the U.S. Air Force has a goal of improving energy efficiency and Rolls-Royce has invested to help this valued customer meet its goal," said Patricia O'Connell, president of Customer Business, Rolls-Royce Defense.
"In doing so, we improved engine reliability and performance, which will enable the Air Force to extend the life of its C-130 fleet for decades while potentially saving billions of dollars."
Rolls-Royce said T56 engine enhancements use technologies from other Rolls-Royce commercial and military engines, including new blade materials and advanced turbine airfoil designs. The upgrade doesn't require any modifications to the aircraft or systems for engine control upgrade can be performed as part of a normal engine overhaul.
The enhancements are projected to help deliver fuel savings of about 8 percent.
The Air Force said the estimated long-term savings from the upgrade will be about $3.5 billion over the C-130H fleet's lifetime.