Understanding the evolving role of the aircraft carrier

A recent piece published in 'Marium', our Center for Global Affairs and Strategic Studies' maritime and naval forum, provides a detailed analysis of the evolving roles of both the submarine and the aircraft carrier, discussing whether the carrier has become obsolete against a new plethora of anti-ship risks in the Indo-Pacific region.

Indeed, the discussion over the role and place for aircraft carriers in modern fleets has been going on for many decades and is still a subject of discussion. As King's College Professor Tim Benbow eloquently describes, "for Air Forces, [carriers] represent the heresy of air power outside their control [...] For armies and for politicians, they are capital-intensive assets which mean less to spend on other defense and non-defense priorities."

However, although precise in some of its assertions, the article raises several topics which are part of a much broader discussion, one about the future of naval warfare in general rather than just a submarine versus aircraft carrier discussion; and thus, deserve to be further explained to avoid any potential misinterpretations.

The aircraft carrier needs to be understood as a powerful naval tool - often referred to as 100,000 tons of naval diplomacy - with a number of different roles which have evolved since its inception in the early 20thcentury and are still evolving in the face of China's massive A2/AD defensive network. In essence, these ships have had six doctrinal roles.

Being the Eyes of the Fleet was their original role before and during World War II, placing them behind the battleline so that they could send their aircraft to scout for the enemy fleet. During World War II emerged a new use for them known as Cavalry, supporting 'hit and run' raids to disrupt enemy operations as the cavalries in the 19th century did. Carriers were thus able to move around the enemy lines delivering quick pulses so long as they remained unlocated by their opponent.

The third role is as Capital Ship, fighting the so-called 'decisive battles' while relying on the principle of calculated risk (fighting only when being sure that the enemy would not inflict more damage that what could be inflicted upon him). Then came the Nuclear Strike Platform (delivering nuclear weapons against enemy territory), primarily as a direct response to the concern in Washington that the B-36 bombers could fail in their task.

Another role is the one known as Geopolitical Chess Piece, which denotes their use by many US presidents during the last decades by way of sending them around the globe to showcase American concern and resolve, commonly referred to as 'showing the flag.' Although not exclusively, the latest deployment of the USS Gerald R. Ford Carrier Strike Group (CSG) to the Eastern Mediterranean has an element of this in combination with its primary task of crisis response.

Lastly, carriers have been used as an Airfield at Sea (the most known role) since the days of the early Cold War, providing support to operations ashore but with their mobility constrained by the limited defenses against sea-control threats (such as those displayed by modern-day China). This is one of the roles which carriers will still continue to play in the near future, although under a much riskier operational environment.

The evolution of the strategic environment at sea, and thus, of naval warfare, have made these roles central to aircraft carrier operations throughout their existence. Roles such as cavalry or eyes of the fleet became obsolete with the advent of new precision-guided weapons, while others remain useful today under very specific circumstances. In essence, the employment of the aircraft carrier throughout history has been governed by the degree of risk the Navy was willing to tolerate, and the circumstances at sea demanding the them to intervene.

The author is right in concluding that carriers remain a critical element in the fleets of most naval powers, and that "both ships are built for different missions, yet they both play critical roles in security and international relations". However, it is precisely because of this last statement that idea of comparing both ships against each other is something to be avoided. They are two completely different assets.

The article also confuses two different discussions as if they were a single one. They are not: one is the discussion over the obsolescence of aircraft carriers (a long-standing discussion which also haunted the mighty battleships decades ago) and the other is the discussion over which of them (carrier or submarine) is better suited to be employed as a nuclear strike platform.

With the former, it is undoubtedly the case that the role of aircraft carriers is evolving and will keep doing so as new technologies reshape the ways naval warfare is understood. But they will remain an important tool for those navies who can find a use for them. As professor Benbow asserts, "carriers will continue to evolve. They will deploy unmanned aircraft alongside their existing complement. They will operate in a closely integrated fashion with other surface, subsurface, air and space systems." In the case of the US, China's network of A2/AD systems in the South China Sea will most likely relegate them to operate behind-at least-the first island chain as part of the US Navy's new concept of Distributed Maritime Operations (DMO).

As for the latter, submarines have clearly substituted carriers as nuclear strike platforms due to their stealth and lethality, and because they are easier to operate for such purposes. Nuclear-powered ballistic-missile submarines (SSBNs) are today one of the primary nuclear strike platforms for many navies around the world, not only the US` Ohio-class or China`s Jin-class (known as Type 094), but also Russia`s Borei-class based in Severomorsk or the United Kingdom`s Vanguard-class based in Scotland. But this is the only aspect in which a comparison between the carrier and the submarine is feasible and actually makes sense.

The article misses the point in another discussion related to carriers. What should a ship need to have or do for it to be considered an aircraft carrier? The author puts all aircraft-capable ships in a single category, even though there are several differences between them. "Currently, only the United States, United Kingdom, France, China, India, Italy, Russia, Japan, Turkey, and Spain have aircraft carriers capable of operating fixed-winged aircraft, with some of those same countries operating helicopter carriers" he argues. However, Spain and Turkey don't have aircraft carriers, but rather amphibious ships capable of carrying an airwing of either SOVL jets or helicopters. They to distinguish among them has to do with their primary roles and design.

Aircraft carriers are labelled with 'CV' to distinguish them from other kinds of carrier-capable ships. In the case of those that are nuclear-powered, like the French 'Charles de Gaulle' or the Ford and Nimitz classes operated by the US, they are labeled with CVN (with the N meaning nuclear). CVs (with variants such as the CVAs, CVBs or CVSs operated by the U.S. during World War II) and CVNs are what we commonly refer to as aircraft carriers, which can perform the different doctrinal roles discussed above and operate both fixed-wing aircraft and helicopters.

From the countries listed in the article, only the United States, the United Kingdom, France, China, Italy, India and Russia operate aircraft carriers. The rest of aircraft-capable ships are amphibious ships, like Amphibious Transport Docks or Landing Platform Docks (LPDs), Landing Helicopter Assault ships (LHAs) or Landing Helicopter Docks (LHDs). Japan's Izumo-class is the only particular case considered by some a helicopter carrier, although it is technically classified as a helicopter-carrying destroyer (DDH) by the Japanese Maritime Self Defense Forces (JMSDF) mainly due to Japan's foreign policy.

Spain's L-61 'Juan Carlos I' and Turkey's L-400 'Anadolu' built by Spanish shipbuilder Navantia are LHDs, as are the Wasp and Tarawa classes from the US Navy. They are able to operate both helicopters and aircraft, and in the case of the Anadolu, unmanned aerial vehicles (UAVs). Yet, their predominant functions are focused on supporting amphibious operations. Thus, as explained by CAPT Robert C. Rubel, "despite their ability to operate STOVL jets, these ships cannot be considered true aircraft carriers" because "they cannot adequately perform the doctrinal roles that aircraft carriers have historically fulfilled".

In conclusion: a discussion between the carrier or the submarine raises many problems and should be avoided. Each of them remains powerful assets, but their employment is not governed by the ability of a given nation to afford them. Rather, their use of strategic needs, which at the same time are dictated by the different characteristics of the strategic environment for each navy. Both of them offer a different set of capabilities, with their advantages and disadvantages, and which will keep evolving over the following decades as new technologies continue to transform naval warfare. Carriers are designed for a series of missions which have also evolved over time, but not all carrier-capable ships can be considered as such. Submarines have substituted the carrier for some kinds of missions, but each of them remains a completely different weapon and should therefore not be compared against one another.