Here's What You Need to Remember: Solutions that have been suggested to meet the new challenges posed by operating in littoral waters include using long-range carrier-based drones that will allow carriers to operate further afield from dangerous coastlines, relying on stealthy submarines to deliver cruise-missile attacks and distributing firepower across a larger fleet of individually less expensive ships.

On May 31, 2017, the U.S. Navy accepted into service USS Gerald Ford, the first of up to four new fleet carriers. The massive 1,100-foot-long vessel will eventually embark around sixty aircraft, including twenty-four F-35 Lightning stealth fighters and another twenty to twenty-four FA-18 Super Hornets. It features a faster elevator for loading munitions, and new electromagnetic launch catapults (EMALS) and arresting hooks to increase the tempo of flight operations while reducing maintenance costs. All of these new perks come at roughly a $13 billion price tag—more than twice the cost of the preceding USS George H. W. Bush.

The United States’ nuclear-powered fleet carriers are currently without rival in the world, and their onboard Carrier Air Wings can unleash tremendous sustained firepower. They serve as potent symbols of American military power, and floating air bases for campaigns in Libya, Iraq and the Balkans.

But how would the supercarriers fare when taking on something tougher than a third-world despot? Advances in missile and submarine technology put in question whether such large and expensive ships are survivable when operating within striking distance of an enemy coastline.

That striking distance is dictated by the roughly seven-hundred-mile combat radius of the carrier’s F-35C stealth fighters, with a shorter range for the Super Hornets. Inflight refueling may extend that distance a bit, though one should bear in mind that a carrier air wing has only a modest ability to refuel itself with its Super Hornet tankers without resorting to larger land-based tanker support. However, sailing a carrier strike group close enough for its fighters to attack coastal targets also places the carrier well within harm’s way of a variety of nasty new weapons.

Long Littoral Reach

One of the newer threats comes from ground-based ballistic missiles—normally a weapon we think of as exclusively used for striking land targets. However, the new Chinese DF-21D Intermediate-Range Ballistic Missiles (IRBM) possess a high degree of accuracy and the capability to adjust course midflight. Both traits enable the rocket to hit a moving target like an aircraft carrier.

The DF-21D “East Wind” IRBM has a range of nine hundred miles, and can adjust its flight path using targeting data fed to it by other platforms, including a series of Yaogan satellites put into space over the last several years. The U.S. Naval Institute claimed the massive kinetic energy of a descending DF-21D, combined with the explosive payload, could potentially destroy a carrier in one hit.

It’s important to note that the East Wind is a mobile weapons system, and could thus prove difficult to preemptively strike. On the other hand, while dozens of the missiles have been deployed to PLA units, it doesn’t appear that the weapon has ever been tested against a moving naval target.

Until recently IRBMs were nearly impossible to shoot down. Today, U.S. cruisers and destroyers carry SM-3 air-defense missiles, which supposedly might be able to swat down an incoming IRBM—although it’s not expected to be easy. There also a number of potential methods for messing up an IRBM’s guidance systems.

Stealthy Submarines—or Subs with Big Missiles

Torpedo-launching submarines sank several aircraft carriers during World War II—though both land- and carrier-based aircraft played a major role in countering the submarine threat. At the time, submarines were especially vulnerable to patrol planes because they had to surface a couple of times a day to keep their batteries charged. Even when lurking underwater, they relied on noisy air-breathing diesel engines that made them easier to pick up on sonar.

During the 1950s and ’60s, new nuclear-powered submarines increased the underwater endurance of subs from hours or a few days at best to months at a time. Nuclear propulsion also enabled them to become far faster and quieter than diesel submarines. Other innovations, such as anechoic tiles and teardrop-shaped hulls reinforced the sonar stealth trend. The quieting technology had reached such a peak by the end of the Cold War that nuclear submarines obliviously collided with each other in 1992, 1993 and as recently as 2009, due to their inability to detect each other.

Of course, carriers are always escorted by destroyers or frigates specialized in antisubmarine warfare. Furthermore, long-distance maritime patrol planes and shipboard helicopters also assist in sweeping the seas for enemy subs. However, while Russian submarines were initially much noisier than their Western counterparts during most of that period, later Cold War designs, such as the nuclear-powered Akula class, were nearly peers to their Western counterparts in quietness.

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Nuclear submarines, however, cost well over $2 billion apiece in modern times, so noisier diesel submarines remain more common across the world. However, in the 1990s Sweden deployed the first submarine to use Air Independent Propulsion (AIP), the Gotland. A variety of AIP technologies allow for a new generation of very quiet and very cheap ship-hunting submarines that cost as little as roughly one-sixth the price of a nuclear submarine, and can operate up to two to four weeks underwater, albeit at fairly slow speeds.

China now possesses fifteen Type 41 submarines, employing the same Stirling AIP system as the Gotland, with another fifteen planned, while dozens of German-made Type 212, 214 and 218 AIP submarines are entering service across Europe and Asia. In fact, the Pacific in particular has become the site of a veritable submarine arms race.

Both nuclear and AIP submarines, including the Gotland, have repeatedly succeeded in sinking aircraft carriers during NATO naval exercises. This is even more alarming considering how cheap the latter type of submarines are to build. In addition to being quiet, AIP submarines possess the range and endurance to hunt for carriers across regional waters, even if most aren’t suitable for deep-ocean operations. Another limitation is that they are significantly slower than the carriers they are hunting, especially while attempting to maximize battery life, forcing them to rely more on ambush tactics.

Still, creeping up to within torpedo range of a carrier strike group is a risky business. Some submarines are designed to hunt their targets from afar. The Russian Oscar-class cruise missile submarine, for example, is not especially stealthy, but it does not have to get close to a carrier group’s surface escorts, thanks to the four-hundred-mile range of its P-700 Granit missiles, which it can launch while underwater. The ten-meter-long missiles travel at supersonic speeds, and are designed to network together to overwhelm defensive countermeasures.

Cruise Missile Defense

This brings us into the realm of missile defense, a long-established threat that carrier strike groups have evolved to counter. While carriers carry short-range antiaircraft missiles and Phalanx CIWS guns for self-defense, their escorting Ticonderoga-class cruisers and Arleigh Burke–class destroyers are armed with a diverse array of medium- and long-range air antiaircraft missiles, designed to thin out incoming missile barrages from hundreds of miles away. These defenses are backed up by networked radars and coordinated by the sophisticated Aegis defense system.

The challenge facing carrier strike groups today is that new antiship missiles are becoming faster, longer-range and more widespread, and can be deployed from platforms including long-distance patrol planes and bombers, small and stealthy fast-attack boats, and even shipping containers concealed in a harbor.

The greater range means new missiles can be more safely lobbed at the carrier without necessarily entering within range for easy retaliation. The greater speed means they are harder to shoot down. And the ability to deploy them from a variety of platforms means the missile-launching units might prove difficult to detect and comprehensively eradicate preemptively.

Take, for example, the Russian Kalibr cruise missile, the “Sizzler” antiship variant of which can strike naval targets up to four hundred miles away. The missile skims just above the sea, making it difficult to detect at a distance, before leaping up to three times the speed of sound on the terminal approach—offering a challenging target for missile-defense systems. The Kalibr can be fired not only from underwater by submarines, but also by relatively small and cheap corvettes.

The heavier but shorter-range BrahMos missile entering use on sea, land and air platforms in the Indian military approaches the target at Mach 2.8, and is designed to perform an L-shaped evasive maneuver to fool a ship’s missile defenses. And China, needless to say, has developed its own range of similar antiship missiles, including both clones of Russian weapons as well as truly indigenous designs.

Even more troubling for a carrier’s air defenses are a new generation of hypersonic missiles—weapons exceeding five times the speed of sound. On June 3, Russia claimed to have successfully tested the hypersonic Zircon missile, with a reported speed of 4,600 miles per hour.