On Oct. 11 the aircraft carrier Gerald R. Ford, the largest warship ever built—and the most expensive—was floated for the first time at Huntington Ingalls’ shipyard in Newport News, Virginia. The 1,100-foot-long Ford, under construction since 2009 at a cost of $14 billion, boasts a new electromagnetic catapult and facilities for more than 70 warplanes and helicopters, including next-generation drones and stealth fighters still in development.

The sheer awe attending Ford’s progress towards front-line service, slated for 2016, has obscured a less visually impressive but arguably more important milestone for the world’s leading maritime force. On Sept. 15, shipyard workers at General Dynamics’ National Steel and Shipbuilding Company in San Diego floated the John Glenn, the second example of a new but little-known class of dock ship called a “mobile landing platform.”

Few people appreciate it, but the innocuous-looking John Glenn is also a sort of aircraft carrier … in everything but name. But she’s a different kind of carrier than Ford. She’s less specialized and much less heavily armed and armored—and greatly cheaper as a consequence: just $500 million. Her construction, starting in 2012, represents an important trend in the U.S. Navy.

Unheralded by many observers, the sailing branch is buying more copies of less expensive and more flexible vessels like John Glenn, rather than investing solely in the priciest, niche kinds of ships like Ford. The Navy thus has a chance at avoiding the dreaded budgetary “death spiral,” in which more and more money buys less and less hardware, forcing a military branch to shrink into irrelevance.

In that way, the brute-simple John Glenn represents the future of U.S. naval power—even more so than the high-tech starship Ford. Cheaper ships can be more numerous. More numerous ships can maintain a wider presence. “Presence is our mandate,” said Adm. Jonathan Greenert, the Navy’s top officer.

Montford Point. NASSCO photo

The empty vessel

John Glenn, her predecessor Montford Point and two more planned platform ships are modified versions of an oil tanker, minus the oil tanks. The 840-foot ships are little more than vast empty storage and a sprawling deck. The Navy envisions buying various equipment kits that can be installed on the MLPs to help them perform different missions.

“One could easily envision this ship serving as a repair ship, a hospital ship, an aviation depot-support ship, or a dedicated [Littoral Combat Ship] mothership in the future — given the appropriate mission capability package was developed and fitted. It’s 800 feet of ‘use your imagination,’” Adm. Mark Buzby, head of Military Sealift Command, told Breaking Defense.

Even without a kit fitted, the baseline vessel has special features. By taking in seawater, John Glenn and the other MLPs can partially submerge, bringing their decks flush with the waves so that hovercraft can move on and off. In this way the MLPs are able to send troops and supplies ashore in the wake of a natural disaster or as part of an invasion or peacekeeping force.

Future kits could include a hangar with extra aviation facilities. The next two dock ships after John Glenn, known as Afloat Forward Staging Bases, are going to be built with the flying gear already installed. The MLPs’ decks can support vertical-takeoff drones, helicopters, V-22 tiltrotors and Harrier and F-35B jump jets. Just two other U.S. ship types—carriers and big-deck assault ships—can launch fixed-wing planes.

With fewer repair and supply facilities than a full flattop like Ford, the MLPs can’t support many aircraft or for very long. Nor can the platform ships, which are slow and lack heavy armor and self-defense missiles, survive in a stand-up fight against a determined foe. They’re also crewed by a few dozen civilian mariners from Military Sealift Command rather than by thousands of combat-trained Navy sailors.

Combat is an option. The British Royal Navy similarly outfitted cargo ships crewed by civilians with flight decks to carry Harriers during the 1982 Falklands War. But the MLPs are best suited for operations short of full-scale war. They’re the right size—and the right price.

John Glenn and her sister ships “more closely resonate with some of the missions of the future,” Greenert said in an October speech. Those missions include “counter-piracy, maritime security and missions to protect and work with allies,” according to Seapower magazine.

Monford Point. NASSCO photo

The affordable fleet

The four planned MLPs are part of a big push for cheaper ships that’s tied to the Navy’s longstanding plans to grow the fleet from today’s roughly 280 vessels to more than 300 over the next decade or so—all without spending much more than Washington’s usual $12 billion a year for shipbuilding.

The sailing branch is trying to acquire: 50 speedy, lightly armed Littoral Combat Ships, 10 fast catamaran transport vessels plus the four dock ships for a combined cost of around $35 billion. Most of these ships are already on contract or under construction.

All of the LCSs, catamarans and MLPs are based on civilian ship designs. With ample empty space, they can carry a wide range of cargoes and aircraft and, in the case of the LCSs, different light weapons.

The idea is for these cheaper vessels wherever possible to take the places of the Navy’s front-line destroyers, cruisers, amphibious ships and aircraft carriers, maintaining American presence on routine patrols while freeing up the tougher, more expensive warships like the flattop Ford to prepare for what they do best: fight a full-on shooting war.

The Navy’s ever-shifting mix of low-end and high-end ships is one of its defining institutional advantages in an era of constrained funding. The Air Force is quickly shedding all but its most expensive and high-tech warplanes, rapidly shrinking into a silver-bullet force optimized for an unlikely major war. The Army likewise is getting smaller and prioritizing sophisticated new ground vehicles.

Only the Navy is able to actually expand its force structure on a flat budget—all thanks to ships like John Glenn, the aircraft carrier by another name.

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