M/T Empire State, USS Tripoli Conduct first CONSOL At-Sea
09 June 2025
UNITED STATES --
Off the coast of Southern Calif., Military Sealift Command’s chartered Motor Tanker Ship Empire State and U.S. Navy amphibious assault ship USS Tripoli (LPH-10) conducted the first Consolidated Replenishment at Sea (CONSOL) between Tripoli and a tanker ship.
The CONSOL evolution began with the two ships making contact and Tripoli moving alongside Empire State. Once alongside, Tripoli fired shot lines to Empire State. The lines were used to deliver the fuel lines to the tanker ship, which were then connected. One hundred seven thousand gallons of F-76 diesel ship fuel was then transferred to Tripoli, taking approximately 40 mins. In total, the two ships were on station, maintaining 100 feet of distance and moving at a speed of 12-15 knots or 14-15 miles per hour for approximately 1.5 hours.
While MSC ships and MSC contract ships conduct replenishment-at-sea evolutions on a routine basis, as any civilian mariner will attest, safety is always on the forefront of their minds. Working within proximity to other ships, with the unpredictability of the seas, the potential for problems to arise is always there, and crews take every precaution seriously, as well as keeping the lines of communication between the ships, open.
“There’s always inherent risk with ships operating so close together. There’s a lot of forces in play with the ocean and the hydrodynamics of it all,” said Capt. Joseph A. Riendeau, Empire State’s civilian master. “Sometimes coordinating can be difficult when dealing with Navy ships since the communication set up is different. The personnel of the Tripoli have been very communicative, making this an easy preparation.”
The ability to take fuel from a tanker ship like Empire State allows ships, to stay at sea to refuel, rather than to come into a commercial fuel pier in port. The concept was developed to keep United States Ships out of foreign ports during times of conflict.
“The ability to CONSOL allows Navy ships to stay at sea and get fuel instead of needing to go into port,” explained Riendeau. “For my ship, it’s nice because we get to practice our UNREP skills and remain proficient.”
CONSOLs with tankers is nothing new for MSC. MSC reintroduced the ability to conduct tanker to oiler CONSOLS-at-sea in 2015. In the 1980s and 1990’s, MSC chartered Champion Class tankers (T5 tankers) UNREPing Navy oilers was commonplace, especially in the Navy’s 5th Fleet area of operations. With the switch to privately owned/Navy chartered tankers, Navy oilers refueling at Navy owned fuel piers became the favored process. Civilian tanker ships, such as Empire State, still maintained the ability to fuel at sea; the demand for fuel consolidation (CONSOL) at sea declined. Reintroducing the technology is a way to utilize a flexible platform that allows MSC to operate world-wide in a variety of missions.
MSC directs and supports operations for approximately 140 civilian-crewed ships that replenish U.S. Navy ships at sea, conduct specialized missions, preposition combat cargo at sea around the world, perform a variety of support services, and move military equipment and supplies to deployed U.S. forces. MSC exists to support the joint warfighter across the full spectrum of military operations, with a workforce that includes approximately 6,000 Civil Service Mariners and 1,100 contract mariners, supported by 1,500 shore staff and 1,400 active duty and reserve military personnel.