Maintenance, repair and overhaul (MRO)

Maintenance, repair and overhaul

Marshall is recognised as a global authority on maintenance, repair and overhaul (MRO) for the Lockheed Martin C-130 Hercules, having built unrivalled experience on the platform since 1966.

Around the world, 18 government fleet operators rely on our capabilities to remain mission-ready and mission-capable - regardless of whether they are operating a 60-year-old C-130B or the latest C-130J Super Hercules. In 2023 alone, Marshall completed over 23,000 MRO tasks across 450,000 hours of aircraft work.

"The unique capabilities, services and response time that Marshall provides for deployed aviation squadrons, in addition to their contractual planned maintenance interval work, are an immense added value and directly contribute to the sustainment of the United States’ fleet of C-130 aircraft.”

Lt Col Kevin M. Ryan

(fmr) Commanding Officer, Fleet Readiness Center Western Pacific, US Navy

We continue to set the industry standard for accurate scheduling and management of maintenance inputs, delivering high-quality, low-risk C-130 depth maintenance with dependable turnaround times. Our exceptionally skilled team of qualified fitters and technicians is supported by our unique authorisation to produce parts in-house, as well as our resilient supply chain and component repair and overhaul network.

Our world-firsts

  • World’s first authorised Lockheed Martin Hercules Service Centre for legacy C-130 B-H aircraft

  • World’s first authorised Lockheed Martin Heavy Maintenance Centre for C-130J Super Hercules aircraft

  • World’s only MRO to gain OEM approval from Lockheed Martin for in-house manufacture of C-130J parts

Our dedicated Repairs Group supports aircraft during maintenance at our facilities and at forward locations when required, calling on Marshall’s decades of platform experience to resolve any on-aircraft issues as quickly and effectively as possible.

“Marshall is known for its unwavering commitment to the global Hercules community, providing proven support to the world’s workhorse.”

George Shultz

(fmr) Vice President & General Manager, Air Mobility & Maritime Missions, Lockheed Martin

Drawing from their familiarity of Lockheed Martin’s C-130 drawings and documentation, the team rapidly determines whether an issue can be resolved through a standard repair approach, or whether a non-standard repair is necessary.

In the latter case, Marshall is able to design and substantiate non-standard repairs C-130B through H aircraft without the need to reach back to Lockheed Martin as OEM; to date, we have completed over 10,000 repairs of this type.

We are extremely proud to be the only MRO in the world approved by Lockheed Martin to manufacture C-130J parts in-house, enabling us to significantly de-risk emerging findings during maintenance inputs and provide unmatched support for difficult-to-obtain and long-lead-time items.

"Throughout the years, we have transformed the relationship into one of cooperating and partnering. The Royal Netherlands Air Force provides the operational input, while Marshall delivers the engineering solutions – a proven and rock solid combination.

“If technical problems arise, Marshall is immediately around to support the Royal Netherlands Air Force. This focus on the customer’s true needs really distinguishes Marshall in the aerospace industry.”

Major General Sotthewes

Deputy Commander, Royal Netherlands Air Force

Flight test and ground running enclosure

Marshall is approved to conduct extensive ground testing and all categories of military and civil flight test, from experimental and developmental testing through to production and operational trials.

Qualification and Experience

Our CAA/EASA/MAA Cat 1 test pilots and lead flight test engineers have extensive experience of military and civil fixed wing aircraft operations and testing. The team’s range of front line experience includes fast jet, tactical and strategic air transport, intelligence, surveillance and reconnaissance (ISR) and maritime operations.

Marshall is a member of numerous accredited professional bodies including the Royal Aeronautical Society, the Society of Experimental Test Pilots and the Society of Flight Test Engineers.

Ground running enclosure

Marshall maintains the largest Ground Running Enclosure (GRE) and compass swing bay in Europe, measuring 90m wide and 20m high.

The multi-million-pound facility enables us to offer an unmatched engine test service, allowing conditioning of the airflow to the propellers and jet engine intakes and accommodating aircraft up to the size of a Boeing 747-400 – while significantly reducing noise during testing.

To learn more about our certification and testing capabilities, click here.

Paint facility

Providing our customers with a range of both standard and bespoke aircraft livery and paint schemes, we offer a cost-effective full strip and repaint capability, ensuring a high quality finish, all of which is delivered in-house through our strategic partnership with a specialist provider.

Capabilities include stripping the aircraft to bare metal, heavy sanding, resealing of all production joints, corrosion removal and treatment, composite repairs and complete aircraft repainting.

OEM-certified parts manufacture

Thanks to our unique OEM-authorised in-house manufacturing and special processes capability, Marshall can support customers by manufacturing parts quickly, easily and independently.

We can also undertake urgent aircraft repair parts manufacture and support the rapid prototyping of new products, overseeing the full process from planning and purchasing through to manufacture, special processes, inspection and release.

Special processes work is an essential part of our capability offering: our manufacturing support facility is NADCAP-accredited and holds prime contractor approvals from Boeing and Lockheed Martin for welding, testing, chemical processing and heat treatment of materials.

  • Our parts manufacturing processes
    • Assembly work
    • Jigs and fixture manufacture and design
    • CATIA programming
    • 3D printing/additive manufacturing
    • Sheet metal fabrication
    • Milling and turning (CNC and manual)
    • Welding
    • Laser wire printing
    • Tool and cutter grinding
    • Chemical processing, including paint
    • Thermal processing/heat treatment
    • Engraving
    • Pipework
    • Electrical wire assemblies
    • Electrical panel assemblies
    • CMM and manual inspection
    • Materials testing

To learn more about Marshall’s advanced structures and materials capabilities, click here.


Marshall’s dedicated Technical Support Group can ensure the continued airworthiness and enhance the capability of aircraft fleets.

The group’s highly experienced engineers are world leaders in providing engineering advice, structural repairs, integrated logistics support, reliability-centred maintenance analysis, obsolescence management, structural and systems integrity, fatigue monitoring, fault analysis and amendments to technical publications.

Protecting fleet availability with engineering and technical support:

  • 24hr technical support hotline
  • Continued airworthiness management
  • Reliability centred maintenance
  • Spares optimisation and cost benefit analysis
  • Technical publication management
  • Obsolescence management
  • Fleet management and repair solutions

“It’s important that we can count on our longstanding service centre at Marshall, to support one of the most active C-130J fleets in the world. Through an integrated team and dedicated support, together we can ensure the Indian Air Force’s C-130J fleet is available and ready for every mission.”

Curtis Jones

C-130 India Programme Manager, Lockheed Martin

Skills and training

Supporting the Lockheed Martin C-130 is in our blood: since 1966 we have led the way in understanding everything about this incredible aircraft.

Understandably, our customers regularly ask us to help to them develop their own capability programmes to support their fleets of legacy aircraft - a need we are fully able to accommodate, providing the necessary skills and knowledge to work proficiently on C-130B through H and J aircraft.

As a UK CAA Part 147 approved training facility, we meet the highest standards of quality assurance and regulatory compliance, enabling us to provide world-class technical training and to conduct examinations at the Aircraft Maintenance License level and perform aircraft type/task training for both the civil and defence sectors on the Lockheed Martin C-130 H, J and L100/382 aircraft.

We work closely with our customers ensure that all material is developed and delivered to meet their bespoke training and operational requirements. Our teaching staff are professionally qualified instructors, with many years of industrial and military experience in the aerospace sector.

We also have the flexibility to deliver training courses at customer facilities to further support the local development of skills and capabilities.

Learn more about our aviation skills and training offering.