Navy Develops CONSOL Capability to Refuel Oilers at Sea

By Edward H. Lundquist - December 1, 2021

The Military Sealift Command fleet replenishment oiler USNS Rappahannock pulls alongside the U.S. flagged tanker Maersk Peary to participate in a consolidated cargo exercise, the first in more than ten years. U.S. Navy photo

Courtesy of Surface SITREP, published by the Surface Navy Association (www.navysna.org)

A key to persistent presence is the ability for the U.S. Navy warships to remain at sea for extended missions, while the key to those extended patrols is to be resupplied while on station by the Navy’s Combat Logistics Force (CLF) that delivers fuel, ammunition and stores to the fleet at sea.

Traditionally the Navy has relied on these logistics ships – including oilers, ammunition ships and stores ships — that are loaded at depots, go out to join with the fleet units to replenish them. Today, some of those depots could be targeted by long-range precision strike weapons, making the entire supply chain vulnerable to attack.

While the U.S. Navy has a large CLF fleet, it may not be large enough in a contested environment. As the range and accuracy of these weapons grows, the need to have alternatives from major supply depots and large replenishment ships becomes more important.

The Navy has the ability to pump fuel from commercial oil tankers to CLF ships at sea. This allows the CLF ships to stay closer to the fleet instead of returning to a supply depot to reload.

There are commercial tankers leased to MSC that have fuel receive-stations installed.

In a 2015 demonstration, U.S.-flagged commercial tanker M/V Maersk Peary, under charter to MSC, refueled Henry J. Kaiser-class fleet replenishment oilers USNS Rappahannock (T-AO 204) and USNS Tippecanoe (T-AO 199) while at sea. This capability is known as consolidated cargo replenishment at sea (CONSOL). While this capability has rarely been used, it does provide logisticians and operators more flexibility and options for refueling the fleet. Under normal circumstances, MSC’s leased tankers would deliver fuel to the Navy’s Defense Fuel Support Points around the world, where the CLF ships would take on their fuel and supplies to distribute to the fleet

Kaiser-class oilers operated by Military Sealift Command provide underway replenishment of fuel, fleet cargo and stores to customer ships at sea. They can carry up to 180,000 barrels of fuel oil and jet fuel that can support a carrier strike group for several days.

The purpose of the CONSOL capability is to resupply a ship that can replenish warships underway at sea. By providing fuel to CLF ships means they don’t have to return to a port to refuel. Eliminating those round-trips to a depot reduces cost and increases time on station to support the fleet. Maersk Peary was under a long-term charter to MSC at the time and was one of four MSC charters that had been specially outfitted to be able to conduct consolidated cargo capability operations with fleet replenishment oilers.

Containerized CONSOL kit

“We’re in the process of developing a ‘kit’ that can be adapted to just about any oil tanker that the military could lease. It’s called the Modular CONSOL Adapter Kit (MCAK),” said UNREP Engineer Richard Hadley of Naval Surface Warfare Center Port Hueneme Division.

By installing it on the deck of the deck of a tanker it can refuel other ships through the receiving ship’s fuel delivery hoses.”

Hadley said MCAK is a temporary installation, and faster to get done. The installation and removal doesn’t require a lengthy shipyard period to accomplish. “We’re developing is the ability to put this kit on very quickly. It’s kind of an ‘instant UNREP station.’”

Hadley said MCAK can be installed, tested, and certified within as little as three days. “You don’t have to go into a big yard period. You get a trained crew to come out and install it, then you test it and the ship is able to sail away very quickly. That is the goal. We’ve conducted a successful demonstration, and have another scheduled. Once we get the design and equipment approved, it will start going into production.”

Most commercial tankers have a relatively standard deck configuration. But MCAK won’t fit on every ship. “We tried to make it as universal as possible,” Hadley said. “But it’s not going to fit everything.”

OPLOG (short for operational logistics) is a group of engineers and naval architects finding ways to utilize technology to increase the efficiency of Military Sealift Command’s Combat Logistics Force (CLF). Sonjae Whang is the NSWC Carderock lead and program manager for OPLOG’s research and development efforts, and the Naval Operational Logistics Distribution Systems (NOLDS) prototype project.

NOLDS is designed to generate solutions, conduct developmental testing (DT) and operational testing (OT), develop and demonstrate prototypes, and transition operational logistics solutions in support of DMO. The NOLDS MCAK prototype project is led by the OPLOG program team from the Naval Surface Warfare Center (NSWC) Carderock Division (NSWC-CD).

OPLOG (short for Operational Logistics Integration R&D) is a group of engineers and naval architects finding ways to utilize technology to increase the efficiency and capability of Military Sealift Command’s Combat Logistics Force (CLF). OPLOG has been working on intra-ship and inter-ship improvements for logistics, handling and movement of cargo more efficiently on a ship, and between ships. OPLOG is also looking at new refueling and logistics systems that can improve the ability to support the distributed maritime operations (DMO) concept. Sonjae Whang is the NSWC Carderock lead and program manager for OPLOG and their current Naval Operational Logistics Distribution Systems (NOLDS) prototype project.

The NOLDS Prototype Project includes eight projects. In addition to MCAK, the team is working on Bulk Fuel Over-the-Shore Storage and Delivery System, Improved Modular Fuel and Cargo Delivery Station, Close-in Fuel Rig, Modified Fuel Rig for Astern and Over-the-Shore Refueling, Open Ocean Bulk Fuel Cache, Littoral Bulk Fuel Cache, and Rapidly Deployable Over-the-Shore Refueling System.

While both Port Hueneme and Carderock have contracting authority, the existing OTA capabilities of the Army’s Program Executive Office Simulation, Training and Instrumentation (PEO STRI) were postured to move quickly to contract for a prototype to simulate the new capabilities, and be able to transition technology to get it into the fleet faster. That’s why the MCAK contract was issued by the Army as part of the Army Contracting Command’s Training and Readiness Accelerator (TReX).

Gryphon Technologies was selected in January of this year to develop the MCAK system from concept through to engineering and fabrication and on to at-scale prototyping.

MCAK is the first project that OPLOG has developed and will be transitioning as part of the NOLDS project. OPLOG is also looking at other refueling and logistics systems that can improve the ability to support the DMO concept.

Whang said his Carderock team works closely with Hadley and the UNREP experts at Port Hueneme.

According to Whang, having a tanker that can be modified quickly to have this type of underway fuel transfer capability without a time-consuming shipyard period gives logisticians greater flexibility. Normally a tanker would have to be taken out of service to give it this capability. “That’s why we came up with this modular kit that has everything organic in the containers.”

Whang said the MCAK system can be transported to a forward area where it can be installed on tankers that can then replenish the fleet oilers so they can get back to replenishing the warships.

The MCAK system has been tested at sea aboard surrogate vessels. “We’re coming to end of development, and getting ready for kitting and containerization,” said Whang.