Auxiliary ships are vital to maintaining a strong and efficient naval fleet. They are designed to perform multiple roles to effectively support combatant ships in and out of battle, as well as complete other similar naval operations. Although auxiliaries assist other ships and do not execute primary combatant operations, they are equipped for self-defense action.
Effective afloat support is decisive in maintaining the wide spectre of current naval operations around the globe. From supporting troops engaged in expeditionary missions, the protection of crucial shipping lanes, to engaging in humanitarian missions, afloat support has never been more important, and this trend will only continue to grow into the future.
Auxiliaries are extremely important for navies of all sizes, as without them, the primary fleet vessels cannot be effective. Thus, nearly every navy maintains an extensive fleet of auxiliaries. However, the composition and size of these auxiliary fleets varies depending on the nature of each navy and its primary mission. Smaller coastal navies tend to have smaller auxiliary vessels focusing primarily on littoral and training support roles. Larger blue-water navies tend to have large auxiliary fleets comprising longer-range fleet support vessels designed to provide support far beyond territorial waters.
In February 2019, the Army sent a letter to Congress warning the country’s organic sealift capacity will fall below the level required to move the Army’s equipment by 2024 if the Navy does not act fast. Sealift is a term used predominantly in military logistics and refers to the use of cargo ships for the deployment of military assets, such as weaponry, vehicles, military personnel, and supplies. It complements other means of transport, such as strategic airlifters, in order to enhance a state’s ability to project power.
“Without proactive recapitalization of the Organic Surge Sealift Fleet, the Army will face unacceptable risk in force projection capability beginning in 2024,” the document says, adding that the advanced age of the current fleet adds further risk to the equation. “By 2034, 70% of the organic fleet will be over 60 years old — well past its economic useful life; further degrading the Army’s ability to deploy forces,” the document reads.
“Shortfalls in sealift capacity undermine the effectiveness of US conventional deterrence as even a fully-resourced and trained force has limited deterrent value if an adversary believes they can achieve their strategic objective in the window of opportunity before American land forces arrive,” the paper reads. “The Army’s ability to project military power influences adversaries’ risk calculations.”
The recapitalization program, known as the Common Hull Auxiliary Multi-Mission Platform, was envisioned as a way to improve the country’s surge sealift force and replace other auxiliary ships such as hospital ships and submarine tenders with a common hull form.
Auxilary Ship Roles
One of the most direct ways that auxiliaries support the fleet is by providing underway replenishment to major fleet units. Oilers and tenders replenish other ships with fuel, ammunition, supplies and food. Tankers transport fuel to other locations, while other auxiliaries transport other ships and Navy personnel. Tenders are specifically designed to support a type of smaller naval unit, like submarines, Destroyer and seaplanes, providing a mobile base of operations for these units. Troopships are used to carry large number of soldiers to operational theatres. Some transport ships are highly specialized, like the ammunition ships employed by the US Navy. Salvage ships rescue and tow damaged ships hurt during battle.
Repair vessels serve as on-the-sea hubs for ship repairs. Repairing ships at sea or in forward areas is important as it allows these units to return to service quicker, while also increasing the chance of survival for ships critically damaged in battle
Radar picket to increase the radar detection range around a force. Communications Relay Ships (AGMR) are floating communications stations. Tracking ship or Range Instrumentation Ship (AGM) are equipped with antennas and electronics to support the launching and tracking of missiles and rockets
Harbor support is a critical support role, with various types of vessels including tugboats, barges, lighters, derrick-crane vessels, and others, used to move ships and equipment around the port facilities, and depot ships and tenders to service ships currently in the harbor. These vessels also help maintain the harbor by dredging channels, maintaining jetties and buoys, and even providing floating platforms for port defense weapons.
A tug or more commonly a tugboat is a secondary boat which helps in mooring or berthing operation of a ship by either towing or pushing a vessel towards the port. A tug is a special class of boat without which mega-ships cannot get into a port. Along with the primary purpose of towing the vessel towards the harbour, tug boats can be engaged in the purpose of providing essentials such as water, air, etc. to the vessel
Some ships produce research of the Navy’s operating environment and test future technology advances. Hospital ship are able to provide care in remote locates.
MSC to Welcome New Class of Tugboats to Fleet
A new class of towing and salvage vessels, will join the U.S. Navy’s Military Sealift Command (MSC) in fiscal year 2021. “The new Navajo class replaces the Powhatan class T-ATF fleet tugs, which provide towing, diving and standby submarine rescue services for the U.S. Navy, and the Safeguard class T-ARS rescue and salvage vessels, which mission includes, salvage, diving, towing, and heavy lift operations,” according to Tim Schauwecker, MSC Towing and Salvage Project Officer.
“MSC and the Fleet commanders will benefit by having new, state-of-the-art and highly capable platforms that can perform a wide range of missions ranging from towing and salvage, diving operations and submarine rescue,” he said. The primary mission of the fleet tug is towing and submarine rescue with the secondary mission of salvage. Rescue and salvage ships conduct salvage with a secondary mission of towing. According to Schauwecker, the Navajo class will combine the capabilities of both classes into a single class for greater efficiency.
“The major improvements include a significant bollard pull increase that will enable the ship to tow virtually any ship currently in the USN inventory. The new ships include additional deck space to account for the requirements of the submarine rescue diving and recompression system, including transfer under pressure, a 40-ton heave compensating crane to assist with underwater salvage operations such as lifting aircraft wreckage out of the water, dynamic positioning which provides the ability to automatically maintain position and heading in the water by using its propellers and thrusters despite the environmental conditions, and berthing for an additional 42 personnel (other than crew) in 2-6 person staterooms. The ship will also have modern automation and engineering systems that include environmentally friendly main propulsion diesel engines,” he said.
MSC search and rescue vessels have contributed greatly to a variety of missions around the world including recovery efforts for John F. Kennedy Jr.’s plane crash, the USS Guardian grounding, TWA flight 800, Hurricane Katrina and the SS El Faro sinking. The introduction of dynamic positioning will greatly enhance the ship’s capabilities.
“During the search for EL Faro by USNS Apache, the tether for the remotely operated vehicle (ROV) had to be cut and re-terminated nearly every day because the ship was not able to hold a fully stable position manually. The search depth was around 15,000 feet and the umbilical would get twisted due to the ships movement. It took four hours for the ROV to get to the bottom and another four hours to get back to the surface. A dynamic positioning ship can hold heading and position within a couple of degrees and a few meters, making it a much more stable platform to operate from,” said Schauwecker.
Future Common Hull Auxiliary Multi-Mission Platform (CHAMP)
The evolving CHAMP concept envisages the use of common newbuild hulls to replace up to five different types of ship: sealift, aviation logistics support, hospital, repair tender, and command and control. But following studies last year, the Navy found one hull wouldn’t cover all the disparate functions the Navy wants to fulfill with the platform. Now the service thinks it has a better answer: two platforms.
“We started out thinking it was going to be one hull … but what we found from our own examination and from industry feedback is that these missions fall into two basic categories,” Capt. Scot Searles, the strategic and theater sealift program manager, said in a brief at the annual Surface Navy Association’s national symposium.
“One is a very volume-intensive category where you need large volume inside the ship — that’s the sealift mission where you are trying to carry a lot of Marine and Army cargo. The other bucket it falls into is the people-intensive mission. When you talk about a hospital ship or a submarine tender, those are people-intensive, and we found we didn’t need as much internal volume. It could be a smaller ship but needed more berthing capability.”
Four US shipyards have received contracts to explore options for a future Common Hull Auxiliary Multi-Mission Platform (CHAMP) that could potentially replace several ageing classes of US Navy (USN) auxiliary and sealift vessels.
Bollinger Shipyards, General Dynamics National Steel and Shipbuilding Company, Philly Shipyard Inc, and VT Halter Marine were awarded firm-fixed-price and cost-plus-fixed-fee contracts on 3 June by the Naval Sea Systems Command (NAVSEA). Each contract is valued at USD2.9 million.
Chinese military exploring new ways of replenishment support at sea
The Taihu, a military supply ship, conducted a replenishment docking with civilian container ship Fuzhou in an offshore area in mid-November 2019 amid the Chinese People’s Liberation Army’s (PLA) exploration of new ways to replenish ships at sea, the PLA Daily reported. This was the first time for Taihu to receive supplies from a civilian vessel, according to the report.
The success of the replenishment laid a foundation for mutual replenishment of various kinds of materials between military and civilian ships, it read. The naval fleet is usually accompanied by supply ships. When supply ships start to deplete their cargo, they need to return to port for replenishment to restore their original capacity.
“It would save a lot of time if other ships could replenish these ships at sea,” Yu Yongyue, chief of staff of the detachment under the Northern Theater Command which Taihu serves, was quoted as saying.
Yu noted that mutual supply at sea between military and civilian ships is common in the navies of world powers.