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"We should not unilaterally assume the function of policing the world. If it is easy for us to go anywhere and do anything, we will always be going somewhere and doing something."
Sen. Richard B. Russell (D-Ga.)
Chairman, Senate Armed Services Committee (1967)

"Strategy is to war what the plot is to the play; Tactics is represented by the role of the players; Logistics furnishes the stage management, accessories, and maintenance. The audience, thrilled by the action of the play and the art of the performers, overlooks all of the cleverly hidden details of stage management"
LtCol George C. Thorpe, Pure Logistics (1917)

"Victory is the beautiful, bright colored flower.
Transport is the stem without which it could never have blossomed."

Winston Churchill

"I don't know what the hell this logistics is that Marshall is always talking about, but I want some of it."
Fleet Admiral E. J. King to a staff officer (1942)

Sealift forces are those militarily useful merchant-type ships available to the Department of Defense to execute the sealift requirements of the national military strategy across the range of military operations. Called "common-user shipping," these ships will be engaged in the transportation of cargoes for two or more Services from one seaport to another or to a location at sea in the theater of operations pending a decision to move the cargo embarked ashore. The sealift force is composed of shipping from some or all of the following sources, depending on the DOD sealift requirement at that specific time: (1) active government-owned or controlled shipping; (2) government-owned reserve or inactive shipping; (3) US privately owned and operated commercial shipping; (4) US privately owned, foreign flag commercial shipping; and (5) foreign owned and operated commercial shipping.

There are several advantages to using sealift. Unit for unit, ships have a higher hauling capacity than aircraft. Ships can also carry heavy or outsized equipment. Ships can pre-position at sea near a projected threat area. They do not need overflight rights, and waters more than 12 miles from land are free for navigation. One disadvantage is the lack of speed in the majority of the sealift fleet. Some of the fleet also requires well-developed port facilities to transfer their cargo to the shore. Sealift ships have little or no defensive capabilities. They also rely heavily on civilian shipping lines and labor.

Looking at a notional 4,000-nautical-mile scenario comparing equal-cost ($20 million) lift forces [C-17s and the new large medium-speed roll-on/roll-off (RO/RO) ships] and assuming no prepositioned ships in the theater, airlift could deliver 72,000 tons of cargo in 36 days. Sealift, on the other hand, could deliver 3,960,000 tons in the same 36 days.

Military Sealift Command ships' noncombatant status makes them less costly to operate than combatant Navy ships. Traditional Navy ships are combatant vessels, meaning they have weapons aboard and are potential targets of enemy fire. As such, they must carry large crews to operate the weapons systems aboard and to protect the ships should they be damaged in battle. MSC ships are noncombatant vessels, operating behind the battle line, and are not considered likely targets of enemy fire. Their noncombatant status enables MSC ships such as the Lummus to maintain an average crew size of less than 40 while Navy ships of similar size generally have crews in the hundreds. MSC ships' merchant mariner crewmembers can also be hired as necessary, while the Navy, even in peacetime, must employ a large number of Navy combatant personnel in case of war. The skill levels of MSC's merchant mariners also enable MSC ships to operate with smaller crews.

International and maritime trade have been growing at twice the rate of the world’s economy for some time. Large merchant vessels are the most flexible and cost-effective modes of intercontinental and coastal transport. Increasingly, new markets and new resources are found overseas. As the world evolves from a collection of disconnected national and regional economies to one global inter-linked economy, freedom of commercial transit on the high seas and through straits and other navigational choke points becomes ever more important. At the same time, the ability of military forces to respond abroad in case of crisis requires the sealift and logistic support that can only be provided by the U.S. merchant fleet. The United States must assure a viable maritime industrial base to satisfy its commercial and military requirements. This is set forth in National Security Directive 28:

"The U.S. national sealift objective is to ensure that sufficient military and civil maritime resources will be available to meet defense deployment and essential economic requirements in support of our national security strategy. The Department of Defense will determine the requirements for sealift of deploying forces, follow-on supply and sustainment, shipbuilding and ship repair. In coordination with the Department of Defense, the Department of Transportation will determine the capacity of our merchant marine industries to meet these requirements and to provide the sealift required to support the essential industrial activity during wartime."

National Security Directive 28 reflected the link between the seagoing armed services, U.S.-flag merchant vessels, the merchant seamen who crew them, and the commercial maritime industrial base of ports, shipyards, and ship repair facilities. Playing a vital national security role since colonial days, the US Merchant Marine is often referred to as another arm of the nation’s defense.

Strategic Sealift Force ships are a part of the Local Defense and Miscellaneous Support Forces. This force consists of

  • Maritime Prepositioning Ships (MPS) (MSC, long-term charter-RO/RO ships) and Prepositioning Ships (PREPOs) include MSC, chartered-barge carriers, partial containers, semisubmersible, freighters, tankers, and transport oilers,
  • Fast Sealift Ships (FSS) (AKR 287 class) (EX-SL 7 prototype) (MSC, vehicle cargo ships)
  • Other ships, including ocean transportation, Hospital Ships (AH 19 class), and Aviation Logistic Support (AVB) ships.

Future contingencies of the Operation Desert Shield/Storm-scale will be even more challenging with regard to sealift demands. In the late 1990s planning stipulated the delivery of forces to theaters within 75 days (compared to the 205 days it took to close the force during Operation Desert Shield/Storm).

The Navy's Military Sealift Command (MSC) provides ocean transportation for DoD cargo and U.S. forces around the world. More than 70 strategic sealift ships transport military equipment, supplies and petroleum to support U.S. forces overseas. This number is expandable and includes both government and privately-owned vessels - mainly tankers and dry cargo ships. In peacetime, more than 95 percent of DoD cargo is transported on US flag ships.

During large strategic deployment operations, sealift support is typically conducted in three phases. MSC is able to provide rapid, sustained response in a changing world with three operational strategies - prepositioning, surge and sustainment sealift.

Pre-positioning (PREPO) afloat is made up of ships from the Afloat Pre-positioning Force (APF) of the Military Sealift Command (MSC). Prepositioning involves having necessary logistical support aboard ships that are strategically located near potential crisis areas. The flexibility inherent in the APF makes this force a key element in joint operation planning; the APF is capable of supporting the plans for the entire range of military operations. Pre-positioned cargoes aboard APF shipping include the capability to provide humanitarian assistance with food rations, medical supplies, habitability sets (i.e., tents), potable water-making machinery, engineer support equipment, and motor transport. To enable the early delivery of combat power to a theater of operations, additional equipment such as tanks and artillery are pre-positioned. Elements of the APF may be temporarily moved to take up position close to a potential employment area, either to signal national resolve during an evolving crisis or enhance the timely delivery of supplies and equipment upon the decision to deploy a decisive force.

The Military Sealift Command (MSC) Prepositioning Program provides operationally ready ships to the military services and the Defense Logistics Agency. At the end of 1999, MSC's Afloat Prepositioning Force consisted of 37 ships, with 35 operating at prepositioning sites in the Mediterranean Sea, Diego Garcia in the Indian Ocean and Guam in the western Pacific. The Afloat Prepositioning Force is divided into three parts:

  1. Maritime Prepositioning Ships operated for the U.S. Marine Corps;
  2. Combat Prepositioning Ships operated for the U.S. Army;
  3. Logistics Prepositioning Ships operated for the U.S. Navy, Air Force and Defense Logistics Agency.

During non-activated periods, ships are layberthed in a 4 or 5-day Reduced Operating Status (ROS-4/5) or in an inactive 10/20 day status (RRF-10/20). While in ROS-4/5, a cadre crew provides for ship's safety, and maintain and operate all major and auxiliary machinery systems. Ships will be capable of getting underway within 4 or 5 days for transit to port of embarkation. While in RRF-10/20, ships are maintained in ready reserve fleet sites, and capable of being towed to shipyard for activation within 10/20 days.

Surge shipping delivers the heavy combat power and accompanying supplies in order to facilitate the deployment of predominantly continental US (CONUS) based forces to anywhere in the world. Surge shipping is the transportation of critically needed military equipment such as tanks, trucks, armored vehicles and helicopters in the early stages of a contingency. Surge shipping must be capable of handling outsized and heavy items of unit equipment. These include large numbers of wheeled and tracked vehicles and helicopters for which RO/RO ships are most suitable. Containerships should not be overlooked in surge operations as they have the capability to transport combat support (CS) and CSS equipment. "Surge" includes ships from the US Transportation Command (USTRANSCOM)-controlled fleet; for example, the Fast Sealift Ships (FSS), the Ready Reserve Force (RRF), Large, Medium Speed Roll-On/Roll-Off (RO/RO) (LMSR) vessels, and the commercial market (when contracted by USTRANSCOM for support of US forces). Surge shipping delivers the heavy combat power and accompanying supplies in order to facilitate the deployment of predominantly continental US (CONUS) based forces to anywhere in the world.

Sustainment refers to shipping provided by the US merchant fleet, mostly containerships, to deliver large quantities of resupply and ammunition to forward-deployed forces augmented as necessary by the RRF. Sustainment shipping maintains the supply pipeline with armament, food and other materiel necessary for continued presence overseas. Resupply and sustainment shipping moves the equipment, parts, and supplies necessary to sustain the force. It is largely breakbulk cargo, which is readily convertible to containerized storage, or POL products.

Comparison of Army and Marine Corps Afloat Prepositioning
Marine Squadron Set Army Brigade Set
M1A1 Tanks 30 (58 planned) a 123
Artillery (155 mm howitzers) 30 towed 24 self-propelled
Bradley Fighting Vehicles 0 126 with TOWs
Armored Personnel Carriers 109 100
Armed HMMWVs 129 (72 with TOWs) 40
Multiple-Launch Rocket System 0 9
Personnel to Marry Up with Each Set 17300 9,900 interim; 19,900 final
Aircraft to Marry Up with Each Set 73 fixed-wing, 75 rotary-wing 0
Strategic Airlift Sorties Required 249 (including sorties 101 interim; 152 final
carrying rotary-wing aircraft)
Sustainment 30 days 15 days for a heavy brigade;
30 days on separate
prepositioned containerships
SOURCE: Congressional Budget Office based on data from the Department of Defense and Lt. Col. Paul Wisniewski, USMC, "Dueling Prepo,"  
                Armed Forces Journal International (September 1994), p. 23.
NOTE: TOW = tube-launched, optically tracked, wire-guided missile; HMMWV = high mobility multipurpose wheeled vehicle.
a. One Marine squadron already includes 58 M1A1 tanks, and the Marine Corps plans to increase the number in the other two squadrons by 1998.

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Page last modified: 07-07-2011 12:53:00 ZULU