The Type 45 Daring Class destroyers are each powered by two Rolls-Royce WR-21 gas turbines.
The contract is part of an innovative approach called Class Output Management, an arrangement for guaranteed availability of the WR-21 engines to support the ships' operational schedules.
The contract is for six years with options to cover the life of the vessels -- in excess of 30 years.
"This contract with Rolls-Royce formalizes the support arrangements for the WR-21 gas turbine," Chris Curtis, head of Supply Chain for U.K. Ship Support Programs at BAE Systems, said.
"We now look forward to working with Rolls-Royce as one of our key suppliers in delivering a highly incentivized and cost-effective support provision to one of the world's most advanced classes of warship."
The WR-21 is a highly efficient marine gas turbine fitted with recuperators that recover energy from the exhaust, which is used to preheat combustion air, which in turn reduces fuel consumption by approximately one-third.
"The WR-21 is the world's most technically advanced marine gas turbine, incorporating a modular design for ease of maintenance and innovative fuel efficiency features," said Matt Nadin, head of Rolls-Royce's Type 45 Support.
Rolls-Royce is supplying a range of mission critical equipment and systems to the British navy's fleet of six Type 45s. In addition to the gas turbines, this includes propellers, shaftlines and bearings, stabilizing fins and low-voltage electrical systems.