Proof-of-concept Improved Modular Fuel Delivery System (iMFDS) will help the Navy convert commercial tankers into E-STREAM-compliant refueling assets — strengthening fuel logistics for Distributed Maritime Operations.

IRON MOUNTAIN, Mich. — July 8, 2026 — Appleton Control Systems (ACS), a division of True Bear Engineering, LLC, has been awarded a contract to develop and demonstrate a proof-of-concept Improved Modular Fuel Delivery System (iMFDS) designed to enhance the U.S. Navy’s at-sea refueling capabilities. The system will be engineered for rapid installation aboard commercial tankers during short-term availability, allowing those vessels to deliver fuel to the fleet with minimal permanent ship modifications and welding.

The award reflects a growing Navy priority: sustaining a dispersed fleet across vast operating areas. As the Navy expands its adoption of Distributed Maritime Operations (DMO), an approach that spreads combat power across wide distances to complicate adversary targeting — the demand for flexible, distributed fuel logistics has grown accordingly. Distributed forces cannot rely on a concentrated supply chain, and the ability to quickly bring additional refueling assets online has become a critical enabler of fleet readiness.

The iMFDS is ACS’s answer to that challenge. Rather than requiring lengthy shipyard periods and extensive structural rework, the system is being designed as a modular, rapidly installable package that can turn a commercial tanker into a capable refueling platform during a short-term availability. By minimizing permanent modifications and welding, the approach reduces cost, shortens installation timelines, and preserves the flexibility of the host vessel.

Engineered to Standard, Built for Harsh Environments

The proof-of-concept system will include all equipment required for E-STREAM-compliant fuel delivery. E-STREAM (Electronic Standard Tensioned Replenishment Alongside Method) represents the Navy’s modernized family of underway replenishment systems, built around electronic controls and programmable performance to move fuel and cargo between ships while underway. Designing to that standard ensures the iMFDS can integrate cleanly with established fleet replenishment practices.

Every element of the system will be constructed to military standards to withstand the rigors of both pier-side and at-sea environments — continuous duty in salt spray, vibration, shock, and temperature extremes. That discipline reflects ACS’s core approach: engineering that goes beyond the minimum requirement, with documentation and quality systems built to perform when testing matters most.

A Trusted Naval Supply Partner

Appleton Control Systems is a proud supplier of shipboard equipment and systems for U.S. Navy and Coast Guard vessels, with more than 50 years of combined team experience in underway replenishment (UNREP) systems. That depth of experience spans control systems, machinery and deck equipment, and mechanical drive solutions for demanding marine and defense applications, which positions ACS to solve technically challenging, customer-specific problems.

The company also views the award as a continuation of a regional legacy. “We greatly appreciate our role in carrying on the long tradition of the naval equipment supply base in Upper Michigan and northern Wisconsin,” the company noted.


“This contract is exactly the kind of work we were built to do, solving a hard, mission-critical problem under a tight standard and delivering a system the fleet can count on. Keeping ships fueled and ready across a distributed force is one of the Navy’s toughest logistics challenges, and we’re proud to bring our underway replenishment experience and engineering discipline to it. It’s also a privilege to carry forward the naval supply tradition of Upper Michigan and northern Wisconsin.”
— Geoff White, Owner, Appleton Control Systems / True Bear Engineering, LLC

What Comes Next

Under the contract, ACS will develop and demonstrate the iMFDS proof of concept, validating an approach that could give the Navy a faster, lower-impact path to expanding its at-sea refueling capacity. Success would offer fleet planners a practical option for scaling fuel delivery in step with the operational demands of Distributed Maritime Operations without the cost and schedule burden of permanent ship modifications.

About Appleton Control Systems

Appleton Control Systems (ACS), a division of True Bear Engineering, LLC, is an engineering-led U.S. manufacturer and systems integrator headquartered in Iron Mountain, Michigan. ACS designs, builds, and supports ruggedized control systems and mechanical drive solutions for harsh-environment applications across marine defense, mining, industrial, and utility markets. The company competes on precision, compliance discipline, and integrated engineering capability and helps customers define, refine, and execute on technically demanding requirements. Learn more at appletoncontrols.com.

Media Contact

Appleton Control Systems

Steve Tarnowski – Business Development Director

Email: steve.tarnowski@acsengr.com

Web: appletoncontrols.com