In a neverending quest for faster, more efficient expeditionary transport, the Marine Corps has learned to embrace emerging transportation technologies. Some—such as the Higgins boat and tilt-rotor aircraft—worked well and are used today. Others—such as rocket ships packed with Marines—never left the drawing board. Still others may someday become a reality.
In the 1930s and ’40s, as war appeared increasingly likely, the Marine Corps developed its amphibious warfare mission. The service scoured the technological landscape of the time, looking for inspiration even from probable adversaries. But the landing at Gallipoli in the First World War proved that amphibious landings could become deadly stalemates on the beachhead, and so the Marine Corps searched for alternatives even as it perfected the amphibious assault.
Parachutists offered one way to outflank the enemy: from above. Inspired by Russian and German airborne operations (no doubt including the German airborne assault on the island of Crete), the Marine Corps stood up three parachute infantry battalions.
And not just parachutes. The technology adopted before the war served the Marines well between 1941 and 1945, with the same equipment supporting amphibious operations across the Pacific from Guadalcanal to Iwo Jima, then again in the Korean War landing at Inchon. As the Cold War settled in and atomic power, helicopters, jet engines, and rocketry seemed the waves of the future, the Marines looked for new ways to get to the fight.
The ability of nuclear weapons to destroy invasion fleets far offshore prompted an investigation into alternative landing concepts that dispersed landing forces until the time of the attack. In January 1950, Marine Brigadier General Gerald C. Thomas, head of the Marine Equipment Board, revealed that the Marine Corps was investigating three new modes of transport for Marine landing forces: seaplanes, submarines, and helicopters.
Assault troop carrier seaplanes. The Consolidated PBY Catalina had proved very useful in World War II, combining range with water-landing capability to patrol vast swathes of the Pacific and Atlantic oceans. A modern troop-carrier seaplane might take off from the United States or forward base and deposit Marines in shallow water near land. A seaplane’s long range would place a large stretch of a defender’s coastline under threat, forcing the enemy to spread its forces over a wider area and weakening individual landing areas.
The seaplane concept would have placed Marines in faster, long-range transports, but they could only offload in the same environment—beaches—as traditional landing craft. A seaplane force would also work separately from sea-based landing forces, making coordination difficult. Adding to the concept’s challenges, the new U.S. Air Force was not a fan of the other services acquiring scores of large fixed-wing aircraft.
Submarine transports. The Marine Corps briefly deployed on submarines during World War II, as when the submarines USS Nautilus (SS-168) and Argonaut (SM-1) landed the 2nd Marine Raider Battalion on Makin Atoll. Neither submarine, however, was configured for amphibious landings, and the raiders went ashore in inflatable boats.
General Thomas and his staff likely envisioned something far larger and more specialized for Cold War operations: large, purpose-built submarine transports that could submerge and sail under enemy fleets and air forces. The underwater flotilla would rendezvous at the designated beachhead, surface en masse, and disgorge infantry, vehicles, and supplies. Submarine landing forces could achieve strategic, if not tactical, surprise.
This idea, too, had shortcomings. The Marine Corps noted at the time that while amphibious submarines might work in deep water, “they would be of limited use in securing ordinary beachheads”—faint praise from a force that trained to secure ordinary beachheads. Another problem was that submarines damaged by enemy shore-based fire would be stuck on the surface, unable to dive.
Vertical envelopment. Helicopters, staging from ships, could allow a Navy transport fleet to sit 100 miles or more offshore, out of range of artillery. Marine helicopter troop carriers would lead an assault, then those same ships could put additional Marines ashore the old-fashioned way—by landing craft—ensuring closer coordination between ground and air-assault forces. This was the mode eventually adopted, and it remains in use today.
Perhaps the most ambitious postwar Marine proposal was Project Ithacus, a proposal to use massive, single-stage-to-orbit rocket ships to transport Marines across the globe. Proposed in 1963 by the Douglas Aircraft Corporation, Ithacus envisioned a squat, blunt-nosed rocket shaped like a .45-caliber bullet. Dubbed a “ballistic transport system,” it would fly a profile similar to an intercontinental ballistic missile, lifting off from the continental United States and briefly achieving low earth orbit before reentering the atmosphere and streaking down onto the landing zone.
Ithacus would have been 210 feet tall and 70 feet in diameter. The rocket featured a crew of 4, with 6 passenger decks holding 210 Marines each, for a total landing force of some 1,200 angry, space-sick Marines. A transport version was to have carried 340 tons of cargo.
The Pentagon envisioned Ithacus as a way of quickly deploying Marines across the globe, without a fleet of vulnerable ships that took days or weeks to arrive. Ithacus had a proposed range of nearly 9,000 miles, which would have permitted a single rocket to carry more than 1,000 Marines to Moscow, Beijing, or Havana in less than an hour.
Ithacus eventually was dropped for being overly ambitious and dangerous. Such an enormous rocket was unrealistic considering the only U.S. manned spacecraft in 1963—the Gemini space capsule—was just 18 feet long and weighed less than 4 tons. Rockets were—and remain—a dangerous form of transportation with a higher failure rate than other modes. The loss of a single Ithacus would exceed Marine Corps deaths at Tarawa.
The monstrous size and ambition of the Ithacus transport was exceeded only by the grandiose plan for getting Marines off the ship in hostile territory. To get men and equipment off a 200-foot tall rocket quickly, each Marine would use a jetpack. While more technically feasible than the 1-million-ton-payload rocket, the jetpack concept was abandoned—and aerial transport for individual Marines along with it.
The September 11 attacks in 2001 renewed Pentagon interest in rapid deployment capabilities, from conventional munitions to small units of armed troops. In 2002, the Marine Corps proposed the Small Unit Space Transport and Insertion (SUSTAIN) system. SUSTAIN was conceived to send a 13-Marine fire team anywhere on Earth within two hours. This capability could be used to send special operations forces on long-range missions, reinforce Marine embassy detachments abroad, or respond to other rapidly developing contingencies.
Launched from the continental United States like Ithacus, a SUSTAIN craft would fly a nonstop mission to the edge of space, unrefueled and without the need for foreign overflight rights. It would then reenter the atmosphere over the target and deploy a parachute to lower the Marines to a gentle landing. Larger vehicles could carry more Marines, and an unmanned “common aero vehicle” resupply craft could fly a similar profile to deliver supplies. The Marines would accomplish their mission and then destroy the lander in place or schedule a pickup.
The Defense Advanced Research Projects Agency commissioned the High Operations Tempo Energetic Access to Globe and Launch Experiment, or HOT EAGLE, to explore SUSTAIN’s feasibility. In 2005, HOT EAGLE managers described the idea of a small space transport as “very promising.” (The report is silent on the possibility of creating a “space shuttle door gunner” military occupational specialty.) Financial considerations aside, the concept’s two major challenges were mass fraction—that is, the ability to deploy only a small number of Marines at a time—and reliability. SUSTAIN backers projected an initial operational capability within 30 years. Little has been heard of the program since.
The march of technology continues to provide the Marine Corps options for deploying troops overseas. The service has been pretty good at picking winners—the idea of seaplane- or submarine-launched landing forces today is less practical than ever, while time has borne out the utility of helicopter air assault.
The jetpack idea has never entirely died, either. Companies in the United States and China are developing a variety of individual transporters, from individual quadcopters to actual jetpacks, that could transform the way individual soldiers and small units move around the future battlefield.
The renewed U.S. interest in space may mean that the idea of military space transport, however expensive and potentially dangerous at present, could someday become a reality. If it does, the Marines almost certainly will lead the way.