WASHINGTON — The U.S. Air Force has awarded Rolls-Royce a sustainment contract to maintain, repair and overhaul engines for the Air Force Global Hawk and U.S. Navy Triton fleets.

The six-year, $420 milllion indefinite-delivery, indefinite-quantity contract also includes sustainment engineering services for Rolls-Royce’s AE 3007H engine, the same one that powers the Global Hawk and Triton, as well as several commercial airliners. The contract services will be completed at Tinker Air Force Base in Oklahoma, where Rolls-Royce and the Air Force have a public-private partnership to operate an engine depot.

“Rolls-Royce has a long and successful history of supporting U.S. Air Force and Navy engines, and our innovative public-private partnership at Tinker Air Force Base has enabled us to work together in a new way and will be a key component of maximizing engine availability," said Paul Craig, president of Rolls-Royce’s defense services division.

“This new contract includes engine services for the Navy’s Triton fleet, and we look forward to continuing this public-private partnership for years to come, focusing on customer support and enhancing mission success,” he added.

The Global Hawk has been suggested as a possible alternative to the JSTARS battle management program.

Gen. Mike Holmes, head of Air Combat Command, told reporters in February the Global Hawk could see further investment as the service looks to replace JSTARS' ground moving target indicator, or GMTI, radar capability.

"The Global Hawk Block 40 is certainly not the same thing as JSTARS, but it does provide useful GMTI information,” Holmes said. “We’ll spend some money to bring that information and make it more useful in real time.”

The Triton UAV is preparing to take on a key role in intelligence, surveillance and reconnaissance missions for the Navy, given its high-altitude, long-endurance capabilities. While the Navy relies on the P-8 Poseidon for anti-submarine surveillance, the Triton will perform high-altitude ISR to fill gaps.

The Australian government announced June 26 it will purhcase six Northrop Grumman MQ-4C Tritons for more than $1 billion. When life sustainment costs are calculated into the deal, the estimated value increases to more than $5 billion.