The UK and its ‘Unsinkable Aircraft Carriers’ – A guide

The term Unsinkable Aircraft Carriers first appeared during the Second World War, to describe the military use of islands in the Pacific Ocean for the American forces fighting the Empire of Japan.

Since then, Britain and other nations have considered similar strategies to secure military power projection. A look at possible British ‘unsinkable carriers’ points to the relevance of the British Overseas Territories.

Between 2014 and 2017, the UK faced a relevant military capability gap following the decommissioning of its last light aircraft carrier, HMS Illustrious, without an immediate replacement. Before that, as part of the 2010 Strategic Defence and Security Review, Illustrious’ sister-ship HMS Ark Royal was decommissioned roughly five years ahead of schedule. Most importantly, the Joint Strike Wing (or Joint Force Harrier) also faced early retirement.

The ‘British Aerospace Harrier II’ (GR7/GR9) performed its last operational flight from a carrier in late November 2010. In practice, HMS Illustrious would be operated as a helicopter platform until her mentioned decommission in 2014.

Britain’s Carrier Strike capability would initiate its recovery following the commission of HMS Queen Elizabeth in 2017, the first of two new British aircraft carriers. Two years later in December 2019, the second ship of the class, HMS Prince of Wales, entered service and initiated a preparation and training process that is expected to culminate in her first front-line duties in 2023. In the meantime, the production of the F-35B Lightning II as a successor of the Harriers progressed.

According to the British Government, after sea-trials, extensive training and exercises, the first British Carrier Strike Group is going to engage on its first operational deployment in 2021. Despite the difficulties and complexities of carrier programme, the Royal Navy is set to reaffirm itself as one of the few naval forces in the world that operate aircraft carriers for the next decades.

However, Britain and other countries can combine the aircraft carriers with another strategy to secure airpower projection over specific areas based on the so-called ‘unsinkable aircraft carriers’. The term first appeared during the Second World War when Allied officers had to describe the advantages of controlling islands in the Pacific Ocean for the war effort against the Empire of Japan. The small islands were strategically relevant as potential air bases for American aircraft in the Pacific-theatre of the conflict, enabling bombers to reach Japanese territory while giving more operational flexibility to the carrier fleet of the US Navy.

In short, an Unsinkable Aircraft Carrier is a term that can be used to describe a ‘political or geographical island’ that is used to increase a nation’s power projection capabilities. Critics of investments in aircraft carriers sometimes employ the term. Nonetheless, the concept itself is generally imprecise as in practice some of the ‘unsinkable carriers’ are not centred on projecting airpower. Instead, they usually act as traditional overseas bases for more than one branch of an armed force.

Moreover, this military concept can be associated with nations facing a relative decline in the world stage and having to choose between conventional carriers or cheaper alternatives. However, a power projection strategy can have ‘Unsinkable Aircraft Carriers’ while retaining the more flexible ‘conventional’ carriers. Moreover, having a “sovereign” unsinkable aircraft capability requires the control of overseas territories or at least enough influence to establish permanent military bases in independent countries.

This strategy has a base concept quite similar to the ‘Island Chain Strategy’ (ICS). The ICS focus in containing hostile nations through a series of installations built on enclaves or islands near the perceived threat, forming a ‘chain’ of barriers that can slow the advance of enemies and enabling the defender to organise its forces without facing the threat of imminent invasion. Some strategists argue that the Unsinkable Carrier approach is an integral part of the Island Chain Strategy or a similar but divergent approach mainly focused on ‘offensive capabilities’.

Amongst the major military powers, at least the United States, China, Britain and France use this strategy or have the wherewithal to build ‘unsinkable carriers quickly’. Other ascending powers like India have interests in exploring the possibilities of this strategy. Concerning China, the country is applying the approach to the disputed islands and atolls in the South China Sea. Since 2013, China has built seven major military installations in different islands. These new military bases have radars, airstrips, missile facilities and ports functioning as some of the most concrete and complete representations of the application of the ‘Unsinkable Aircraft Carrier Strategy’. While these bases open the South China Sea to Chinese control and serve as “access-deniers”, its ports function as staging points for Chinese operations further away. However, in 2019 reports emerged stating that the conditions of some of these state-of-the-art installations were facing quick deterioration.

The United States currently employs this strategy mainly in the Indian and Pacific oceans. In the same way that the US Navy has the largest fleet of aircraft carriers in the world, the United States is the nation that has most bases that can be classified as ‘unsinkable aircraft carriers’. In the Indian Ocean, the foremost example is the Anglo-American base in Diego Garcia; the main island of the British Indian Ocean Territory (BIOT). The Island’s vast military installations and geographical position has made it one of the most relevant bases used by the American forces when deploying to South East Asia, the Middle East and parts of East Africa. Diego Garcia was also extensively used as a staging point for military campaigns in Iraq and Afghanistan.

In the Pacific Ocean, the United States controls several strategically important possessions and have extensive agreements with Japan, which allows the presence of American forces in Japanese territories. However, the US Air Force does not exclusively use the majority of these installations. The US Navy is the primary user of the base on Guam. Still, the Air Force operate airfields on Kwajalein Island (Marshall Islands) and Wake Island while having extensive installations on Japanese and South Korean territories. Amongst the American bases that can be classified as ‘unsinkable aircraft carriers’, the Kadena Air Base is a fine example.

Kadena is the most active and largest US Air Force base in the Far East. Additionally, Taiwan is generally classified as a potential ‘unsinkable American aircraft carrier’. During the Cold War, some writers also saw the UK and Japan acting as ‘staging bases’ or ‘unsinkable carriers’ for the American forces.

Through its Overseas Territories and political links with former colonies, the UK has numerous potential assets that can be classified or quickly adapted as ‘unsinkable carriers’. The British debate about this strategic approach goes back to the Cold War. In the early 1960s, the Royal Air Force (RAF) was a proponent of an approach called “Island Strategy”. The RAF held the position that the whole of Africa could be covered from the UK and its insular territories if demanded, arguing that the plans for new aircraft carriers for the Royal Navy were unnecessary. Thus, the ‘island air bases’ could provide greater value for money, and Britain should explore the potential of its overseas possessions investing in an ‘unsinkable carrier’ strategy.

The Admiralty counter-argument stated that carriers could provide greater flexibility than islands and that the risk of the end of British rule over some territories could hit Britain’s military capabilities significantly. Additionally, the ‘conventional’ carriers were an advantage for crises could emerge beyond the reach of the British airbases and the installations themselves could be engulfed by enemy military superiority and eventually used against Britain. These arguments also indicated that the ‘Island Strategy’ was a defensive approach in its core. The Admiralty’s position only grew more robust than the RAF’s during the decolonisation of British colonies in Africa and Asia that were part of the planned Island Strategy. Therefore, the Royal Navy retained its Carrier Strike capability throughout the Cold War.

By the late 1960s and early 1970s, the British Government had decided to withdraw from most of its commitments East Suez enabling the ‘sinkable but moveable’ approach to overcome the remaining ‘static but unsinkable’ ideas. Nevertheless, Britain would retain strategically relevant Overseas Territories that were used in the nineteenth century as coaling stations for the Royal Navy and British merchants. It is possible to identify some islands or enclaves under British protection acting as staging points for Britain’s expeditionary capabilities.

The most relevant possessions are Gibraltar, the Sovereign Base Areas of Akrotiri and Dhekelia, the Falkland Islands, Ascension, Santa Helena, Diego Garcia, Bermuda, and to a lesser extent the Turks and Caicos Islands, Montserrat, Anguilla, the Cayman Islands and the British Virgin Islands. It worth noting that every British Overseas Territory has potential military use, yet not every possession shares the same strategic location value.

Diego Garcia, a part of the BIOT, is one of the most common examples of an unsinkable aircraft carrier. Although the US military forces are the primary users of the extensive military installations, Britain maintains a permanent presence through the Naval Party 1002 (NP1002) for the civil administration of the territory. Moreover, the base is continuously open to the British Armed Forces. Except for the remote British territory of Pitcairn in the southern Pacific Ocean, the BIOT is last possession under Britain’s control East of Suez. As tensions grow between the Western powers and China, Diego Garcia enables is set to remain a crucial asset for independent military deployments to South East Asia.

Beyond the BIOT, the Sovereign Bases Areas of Akrotiri and Dhekelia are other examples of ‘unsinkable aircraft carriers’. The Western Base, Akrotiri, is home of a large Royal Air Force station (RAF Akrotiri). At the same time, the Eastern Base (Dhekelia) has a Joint Service Signal Unit that collects signals data and intelligence from the Mediterranean and Middle East region. Despite being focused on signal units, Dhekelia has a small airfield employed as a Helicopter Base for the Army Air Corps. The British Government retained these two enclaves during the ‘London and Zurich Agreements’ of 1960, which resulted in the independence of Cyprus.

Covering roughly 3% of the land area of the Island of Cyprus, the two bases grant Britain a privileged position for deployments East of Suez or operations throughout the Middle East. Since 2014, through Operation Shader, Royal Air Force has been using RAF Akrotiri as a launchpad for airstrikes against the Islamic State in Syria and Iraq. In May 2019 the British Government announced that ‘several F-35B Lightning aircraft from the 617’ flew from their base at RAF Marham ‘to spend six weeks at RAF Akrotiri as part of the Exercise Lightning Dawn’.

Situated on the Western entrance to the Mediterranean, Gibraltar is another British Overseas Territory that functions as a relevant staging post for the expeditionary capabilities of the British Armed Forces. However, classifying Gibraltar as an ‘unsinkable aircraft carrier’ requires one remark. The enclave of Gibraltar exemplifies an underlying problem with the definition of an ‘unsinkable aircraft carrier’ for most geographic or political islands rarely are used exclusively as bases for airpower. Additionally, Gibraltar – and other British possessions – are relevant for the expeditionary capabilities of the UK, which are centred on the Royal Navy. Therefore, in practice, airpower has had no monopoly or privilege over these ‘unsinkable carriers’.

The British Territories in the South Atlantic share Gibraltar’s relevance. Officially, the UK has three Overseas Territories in the area: ‘Saint Helena, Ascension and Tristan da Cunha’, the Falkland Islands and ‘South Georgia and the South Sandwich Islands’. Amongst these possessions, Ascension and the Falklands have been attracting significant military interest from the British Government since the nineteenth century, but especially after the Falklands War. In the case of Ascension, the United States and Britain jointly operates the Island’s airfield, called RAF Ascension Island or ‘Wideawake Airfield’. Ascension’s infrastructure is essential for securing connections with the Falklands without relying on the willingness of regional countries. Britain witnessed Ascension and Gibraltar’s relevance during the Falklands War when the British Task Force heading to the South Atlantic used both territories. Despite its importance, in 2017, the British Government confirmed that the RAF Ascension would be partially closed due to potholes on the runway. In January 2020, the US Air Force Installation Contracting Agency awarded a contract to an American construction firm (Fluor) to repair the airfield’s runway until the end of 2022.

In 2015, an international airport was completed on Saint Helena. Following delays, commercial flights began in 2017. The airfield gives Britain another potential staging point in the South Atlantic for deployments to the Falklands and western coast of Africa. Despite that, Saint Helena’s military potential is overshadowed by the well-established presence at RAF Ascension.

The Falkland Islands is another British territory that could be an ‘unsinkable aircraft carrier’. RAF Mount Pleasant, the territory’s main military installation, has its origins in the aftermath of the Falklands War. Britain was determined to protect its overseas possession and the Islanders’ right to decide their political future after the war that led to the death of 255 Britons, 649 Argentines and three Falkland Islanders. In 1985, RAF Mount Pleasant was officially opened, becoming fully operational the following year. The military installations host forces that have as duty preventing invading troops to overrun the British control before reinforcements can arrive from the UK. The RAF Mount Pleasant, Mare Harbour and the three ‘early-warning and airspace control radars’ present throughout the Falklands give the British forces a relative control of the surrounding areas, including the Drake Passage and the Strait of Magellan. Few of the major military powers can claim a similar control over the extreme south of the Atlantic.

Thus, considering the British territories and military installations throughout the area, the South Atlantic is secured within Britain’s power projection capabilities. However, this relative control of the South Atlantic is largely possible due to every “link” of the British chain of islands in the region. Thus maintaining a modern and fully operational military infrastructure on Ascension and the Falklands Islands is central to any conception of the South Atlantic as a main British theatre of operations.

The majority of the British Overseas Territories in the Caribbean and North Atlantic could be used or adapted to become an ‘unsinkable carrier’. Nevertheless, excluding Bermuda, – that has seen its geostrategic position being used by the RAF and US Air Force during the World Wars and Cold War – other possessions have not witnessed the same level of military presence. Additionally, following the reduction of the British military presence in the region as part of the decolonisation process, Britain would maintain a training base in Belize.

Lastly, the infrastructure of the Cayman Islands, Turks and Caicos, the British Virgin Islands and Anguilla in the Caribbean can offer support to Britain’s military during emergencies. It is worth mentioning that Montserrat’s only international airport was destroyed in 1997 by an eruption of the nearby Soufrière Hills volcano; its replacement was completed in 2005, but the new runway is half the length of its predecessor. Despite the significant reduction of British military presence in the Caribbean since the 1960s, the British Government continues deploying vessels of the Royal Navy and Royal Fleet Auxiliary to the region, especially during the Caribbean hurricane seasons.

Defence agreements with friendly nations are also part of London’s strategy to retain a voice in different regions while keeping the costs as low as possible. Since 2014, the country has been investing in permanent military bases in Bahrain and Oman as part of an approach seeking to reaffirm Britain as a global player. However, the Royal Navy and Royal Fleet Auxiliary are the focus of these military bases. The leading British base for air operations in the region is located at the Al Udeid Air Base, in the United Arab Emirates. Deployments of the Operation Shader use Al Udeid and RAF Akrotiri.

The Five Power Defence Arrangements (FPDA) also enables the UK to have close defence cooperation with Australia, New Zealand, Malaysia and Singapore. Additionally, Brunei permanently bases a British Gurkha Battalion as part of agreements between London and the Bruneian Sultan. Currently, the British presence in Brunei is centred on land forces that have access to significant military facilities and training areas of the Asian nation.

Therefore, Britain is amongst the few countries that have at disposal ‘unsinkable aircraft carriers’ or can quickly adapt the existing infrastructure of overseas territories when needed. As the country with more military bases overseas, the United States is also the one at the forefront of the ‘unsinkable carrier’ strategy. The American Government uses bases in foreign countries or American possessions throughout the world that act as supporting assets to the US Navy fleet of aircraft carriers. These bases are a valuable addition to the United States’ power projection, aiding the nation to secure its presence overseas. In a reduced scale, China is experiencing the strategy in the South China Sea while France shares some of Britain’s characteristics: the use of its overseas territories or agreements with friendly countries.

As already explained, the British Overseas Territories are essential assets for the UK’s expeditionary capabilities. Some of these territories have military installations that have been supporting British interests around the world for decades. However, classifying them as ‘unsinkable aircraft carriers’ might downgrade their relevance for the other two branches of the Armed Forces while overstating their value for British airpower. The British Overseas Territories are more than airfields to the UK. Although the current local installations limit their capabilities, the Territories can act as supporting bases for the three branches of the British Armed Forces.

In 1982, Gibraltar and Ascension confirmed their importance while providing staging points for the Task Force sent to recapture the Falkland Islands. Nevertheless, the Overseas Territories complements conventional military capabilities. Without an adequate Armed Force, Britain might witness itself being unable to utilise the strategic potential of these possessions when necessary. At the same time, the label ‘unsinkable aircraft carriers’ would be insignificant without the assets meant to use them when demanded.

Since the 1960s, Britain gave independence to several possessions that once were considered strategic pivots of British power. Amongst these, Malta is one of the few that had the label ‘unsinkable aircraft carrier’ when London granted independence. However, some territories opted to maintain their political links with London, continuing to be defended by the UK against external threats.

The current British Overseas Territories have been supporting British interests around the globe for centuries. The debate about classifying and using some of them as potential ‘unsinkable aircraft carriers’ displays their enduring relevance to the UK.

In short, even considering the term and its usefulness as a strategic approach open to criticism, a significant part of any study about a ‘British Unsinkable Aircraft Carriers’ strategy has to take into consideration the potential of the British Overseas Territories.