LONDON — The Marshall Aerospace and Defence Group is the chief beneficiary of a £369 million ($547 million) deal announced Dec. 30 by the British Ministry of Defence to support the Royal Air Force's fleet of C130-J Hercules airlifters up to 2022.

The deal is the latest phase of the Hercules Integrated Operational Support (HIOS) program signed by maintenance provider Marshall, aircraft maker Lockheed Martin and engine supplier Rolls-Royce in 2006.

In a joint statement, the three companies said the program had increased –J availability by a third and cut costs by about 20 percent.

The agreement will take spending on HIOS-related support to more than the £1 billion mark with the prospect of more to come now that the MoD has decided to extend the planned out-of-service date of the Hercules fleet from 2022 to at least 2030.

Although the out-of-service date in the recent government strategic defense and security review (SDSR) was revised to 2030, one MoD source said it could be 2035 before the fleet is finally scrapped.

Marshall celebrates it 50th anniversary of working with the RAF on the Hercules in 2016 and any extension in service to 2035 could see the company's involvement in the platform run to nearly three quarters of a century.

The company has built a substantial business on the back of the work for the RAF and supports another 10 Hercules operators around the world from its Cambridge, England, base and is working on several airframes for customers like Sweden and the Netherlands.

Adraian Baguley, the director of air support at the MoD's Defence Equipment & Support organisation, said the new HIOS deal "builds upon improved performance at a lower cost that will deliver strategic and tactical air-transport capability and excellent value for UK defense."

The SDSR said the  24 strong -J fleet would eventually be reduced to 14 aircraft. Two aircraft earmarked for helicopter refuelling duties are included in the fleet.

The –J's are extensively utilized by British special forces for covert insertion and supply although it does also undertake other conventional airlifter missions alongside the RAF's fleet of Airbus A400M and Boeing C-17 aircraft.

The A400M was to have taken over special forces duties after 2022, but commanders here have argued for some time that the Airbus aircraft was too large for the role.

The RAF flew it's first A400M operation earlier this month supporting the deployment of additional combat jets to their base in Cyprus as Britain extended its bombing campaign against Islamic State to include Syria as well as Iraq.

Running on elements of the C-130J fleet is part of a significant hike in special forces spending revealed in the SDSR in November.

"We will upgrade our helicopters and transport aircraft so that they can deploy further and faster," the SDSR said.

The Hercules will likely be updated with installation of the new Block 8.1 standard upgrade of avionics and other systems, some earmarked to enhance special forces capabilities. Some fatigue-related work is also a possibility.

The airlifter was one of several platforms to have their out-of-service date extended by the SDSR.

The Sentry airborne early warning aircraft, Sentinel R1 battlefield surveillance platform, the Shadow intelligence machine and the Rivet Joint signals intelligence aircraft can all expect to be involved in extended maintenance arrangements with industry. In some cases, like the Sentry, a sizeable modernization program could also be in the cards.