This piece was originally written and submitted as part of an essay contest in September 2023.

By Trevor Phillips-Levine and Andrew Tenbusch

A large Japanese force emerged from the San Bernadino Strait, comprised of battleships and heavy cruisers, including the flagship Yamato. All that stood between them and the vulnerable U.S. landings at Leyte were the escort carriers, destroyers, and destroyer escorts of Seventh Fleet. Admiral Halsey’s Task Force 34 was ostensibly tasked to guard the San Bernardino Strait, a strategic approach north of the amphibious landings. But Halsey was then hundreds of miles away, steaming northward in dogged pursuit of a decoy Japanese carrier force. Urgent radio traffic from Commander Seventh Fleet did little to throw Halsey from pursuing the Japanese carriers until he received a pointed inquiry from Admiral Nimitz, Commander in Chief, Pacific Fleet and Pacific Ocean Areas.^1,2 The Japanese fleet successfully deceived Halsey and obfuscated their actual center of gravity for the operation by offering up some of their most prized assets as bait.

In chess, “The Queen Sacrifice” is well-known. The queen is one of the most important pieces and possesses wide mobility. In a queen sacrifice, a player risks their queen to gain a key advantage later, leveraging the perceived importance of the piece with their opponent.³ The U.S. Navy viewed its carrier forces as its center of gravity. If given the opportunity, the Japanese predicted that the U.S. Navy would pursue their aircraft carriers because the Navy would assume them to be similarly vital to the Japanese. Like chess, the battlefield is becoming an arena of persistent observation from robust satellite constellations.⁴ In a world of near-perfect information, deception becomes crucial, and the more believable the ruse, the higher the chances of success. Ruses can be made more believable by capitalizing on an adversary’s cognitive biases, such as their perceptions on what platforms are especially crucial to naval operations.

China already possesses the world’s largest navy, and the U.S. is unlikely to match China’s industrial capacity and speed in shipbuilding.⁵ Therefore, deterring and, if necessary, defeating China in naval combat will require deception to minimize U.S. vulnerability to the heavy attrition that can be quickly inflicted in a war at sea. For deception to be effective, the U.S. Navy must first be aware of how its enemies perceive its centers of gravity and then possess the willingness to use its prized assets in unconventional ways. Rather than try to force a traditional use case of the carrier onto an unprecedented threat environment, the Navy should consider novel approaches to carrier employment. Based on the currently limited reach of the Navy’s air wings, the carrier’s best use may be as a decoy force.⁶ 

Enduring Truths 

Since Fleet Problem IX in early 1929, the U.S. aircraft carrier has been recognized as an invaluable asset. However, surprise encounters with submarines and surface combatants revealed its vulnerabilities. The short range of the carrier air wings required the aircraft carrier to maneuver perilously close to the objective.⁷ Much depended upon accurate intelligence, the boldness of commanders, and luck. Some naval leaders remained unconvinced by tactics that placed the aircraft carrier at great risk. Others felt that the risk and loss of the carriers were completely justified if in the pursuit of “decisive” results.⁸

Fleet Problem IX and subsequent Fleet Problem exercises informed the development of U.S. carrier tactics for World War II. It also reinforced the desire among commanders to eliminate the enemy carriers first.⁹ Carriers remained vulnerable to shore-based air and susceptible to submarine attack. The debut of the missile age by the Kamikaze showcased the carriers’ vulnerabilities when forced within range of shore-based air and the difficulty of defending against guided munitions.¹⁰ By the war’s end, the U.S. had lost three escort carriers to Kamikazes and nine fleet carriers had taken Kamikaze hits. However, the fleet experienced greater losses among support and picket ships as they were often the first ships Kamikaze pilots would encounter.¹¹

Submarines continued to be a persistent threat. During World War II, the Japanese lost eight carriers to submarines.¹² The British lost five, while the U.S. lost four.^13,14 Decades later, during the 1980s Falklands Campaign, the British deployed 11 destroyers, six submarines, and 25 helicopters to hunt down an obsolete Argentine submarine threatening its carrier task force.¹⁵ That Argentine submarine still managed to fire torpedoes against the British fleet and survive the war. Submarines present an asymmetric threat and are costly to defend against, requiring great resources to find and track. Over the years, the Navy hollowed out the carrier’s organic anti-submarine warfare capability, leaving the air wing dependent on inorganic assets like the P-8A Poseidon to find lurking submarines across wide areas. Yet these are assets that may not be able to follow the carriers into heavily contested seas, and and the effects of climate change will likely increasingly constrain detection ranges.¹⁶

The threats to aircraft carriers are enduring and intensifying with technological advances. The necessity for carriers to maneuver within enemy weapon engagement zones to deploy offensive combat power has remained true for much of history, except in some recent regional wars. What has changed is that the carrier is less equipped to defend itself than in the past, and there is a perceived lack of willingness by U.S. leadership to stomach the loss of an aircraft carrier for the sake of employing its air wing.¹⁷

Neutering the Aircraft Carrier

Symbols of American power projection, U.S. aircraft carriers prominently featured as American options for political messaging and de-escalation. President Bill Clinton dispatched two carrier strike groups to “monitor” saber-rattling after the U.S. approved a visa for Taiwan’s leader in 1996, during the “Third Taiwan Strait Crisis.”¹⁸ The dispatched U.S. carrier strike groups were to reassure allies and bolster regional credibility. At the time, a broad consensus existed that the People’s Liberation Army was “not in a position to take Taiwan.”¹⁹ The carriers’ successful interference in China’s campaign of intimidation against Taiwan during the crisis marked a seminal moment for the PLA. Since then, China has substantially improved its area denial capabilities, joint force integration, amphibious capability, and ocean surveillance. Today, analysts acknowledge that the People’s Republic of China is better positioned to mount an invasion – and threaten carriers – than at any other time in its modern history.²⁰

The People’s Liberation Army emphasizes neutering U.S. power projection capabilities by fielding precision weapons like the Dong Feng-21D and Dong Feng-26 ballistic missiles. Besides conventional strike capabilities for infrastructure targets (i.e., airfields or ports), the Dong Feng series of weapons also possesses maritime strike capabilities to target warships.²¹ The ranges of these weapons exceed the striking range of a carrier’s current embarked air wing.²² If the carrier is to utilize its striking power in a Pacific scenario, it must close to well within range of powerful shore-based capabilities.

The accuracy of long-range precision weapons depends upon extensive, over-the-horizon cueing networks and mid-flight retargeting capabilities.²³ China’s long-range weapons are credible because of their supporting targeting infrastructure, including over-the-horizon radars, terrestrial and aerial surveillance assets, and satellite constellations.^{24, 25} The vastness of the Pacific theater and the number of ships plying the ocean at any given time impart data processing delays, where analysis must sift through benign data and isolate contacts of interest. The speed of a decision cycle is referred to as the “OODA” loop, where a speed advantage relative to the adversary is a critical component of victory.²⁶ Accelerating decision cycles will likely drive artificial intelligence integration, which can sift copious amounts of data at speeds and accuracy exceeding human analyses.²⁷ China desires to lead in artificial intelligence, and reporting indicates that its military is heavily involved in its development. The PLA views artificial intelligence as key in “intelligentized” warfare environments and disrupting the decision-making pace of adversaries.²⁸ Therefore, it is reasonable to assume that China will likely mate its extensive ocean surveillance capabilities with artificial intelligence to sift through benign noise to find carriers and other warships.

Artificial intelligence may also be used to determine operational strategies. Some algorithm training sets use historical data. Historical data composed of human decision-making and behavior are imbued with human biases. These use cases can impart latent bias to the algorithm and, in the case of the U.S. carriers, potentially cause those algorithms to inherit an affinity for carriers’ centrality to U.S. naval operations.^{29, 30} In fact, biases may manifest more significantly in algorithms, and humans’ trust in their output permanently skew their perceptions in future decision-making.³¹ Indeed, carriers played a central role in Japan’s naval campaigns before the Leyte operations, much as they did in the interwar period during the Fleet Problem exercises, reinforcing perceptions of their continued importance to Halsey.³² Artificial intelligence that learns from training data from the past 80 years of U.S. naval operations could develop similar perceptions and become self-reinforcing for human users.

Naval Deception

At the tactical level, paint schemes during both world wars on Allied shipping were designed to break up outlines, making identification and targeting by the enemy more challenging.³³ New paint schemes on Russia’s Black Sea fleet may be an attempt to thwart target recognition algorithms and image-processing seeker heads.³⁴ Other historical tactical deceptions took on more elaborate forms, as with Britain’s Q-ships during World War I. Masquerading as merchant ships to lure submarines to the surface, submarines were then ambushed by their not-so-helpless prey.³⁵

Today, arguments for the U.S. Navy to reintroduce decoys to divert attention and complicate surveillance are gaining favor.³⁶ While China’s surveillance apparatus is formidable, it is finite, and each diversion or false target saps resources from finding the true one. The PLA’s weapon allocations are impacted by this uncertainty by tying down warheads. A weapon must be reserved for a perceived threat, eliminating it as an option for striking a different target. As such, fleets-in-being require considerable diversions of resources and capabilities kept in reserve, whether those fleets are a direct participant in an operation or not. For example, Ukrainian forces were forced to divert precious resources to monitor troop concentrations in Belarus and a Russian amphibious fleet in the Black Sea, despite the unlikelihood of either force launching a successful attack.³⁷ Forcing China’s military to expend attention and munitions on ghost fleets and attractive diversions will be an essential element of operational art during conflict.

Magruder’s Principle is a concept in deception that states it is “easier to exploit the enemy’s beliefs than to alter those beliefs.”³⁸ An enemy may be completely blinded by target fixation and confirmation bias if the deception is adequate. When Halsey pressed his attack against Japan’s carrier force, there were signs it was a diversion. Navy carrier scout planes reported empty flight decks and little fighter cover over the Japanese carriers, an anomaly that should have raised many red flags. But convinced of their importance, likely influenced by the carrier’s importance to him, Halsey continued his pursuit. And despite increasingly desperate radio traffic from the commander of Seventh Fleet, he remained convinced that the destruction of Japan’s carrier force took priority over all other efforts.

Japan’s desire to use the carriers as a decoy force may have stemmed from how their air wings were previously decimated in the “Great Marianas Turkey Shoot” in the Battle of the Philippine Sea. There Admiral Spruance made a different calculation than Halsey, opting to shape the deployment of his task force in such a way as to give priority to protecting the beachhead rather than fully committing to a chase against Japanese carriers. The Japanese sent hundreds of their carrier aircraft into the teeth of American fleet defenses only to inflict negligible damage against U.S. capital ships. Unknown to the Americans, the massive losses they inflicted against Japanese aircraft removed Japan’s carriers as a credible force for the foreseeable future. When Japan opted to use its flattops as decoys, they were good for little else.

While there has been much contemporary debate on the survivability of the carrier, the Navy should also consider how the survivability of the air wing may affect future roles for flattops. An aircraft carrier is most vulnerable during aircraft launch and recovery operations when forced on predictable headings. To find a beehive, one needs only to find a bee to follow, a tactic Kamikazes used well by following returning Navy fighters.³⁹ Unknown surface contacts that are launching and recovering multiple jet aircraft may strongly stand out against the backdrop of maritime traffic to an adversary’s ocean surveillance network. However, an aircraft carrier unburdened with flight operations is free to use a variety of frustrating tactics against the enemy. In either case, a diversion requires the devotion of more surveillance for increased scrutiny by the enemy, slowing their decision processes and diverting attention.

Overcoming the Institutional Barriers

Using the carrier in non-traditional ways, like a diversion in a deception campaign, will probably meet strong resistance within the Navy. The aircraft carrier remains one of the prominent symbols of American power and prestige. Despite the occasional essay questioning the value proposition of carriers in robust peer environments or advocating unconventional uses, the U.S. Navy overwhelmingly views its carrier fleet as its crown jewels.^{40, 41} These viewpoints ossified after the end of World War II as the battleship’s fate had been sealed and the aircraft carrier took its place as the world’s premier capital ship. Over the decades, carrier aviators pervaded the Navy’s ranks and the halls of industry and government, cementing a strong advocacy network into place.

In 2015, former Navy captain and strategist Jerry Hendrix pointed out that some planners and leaders appear focused on protecting a traditional use case for the aircraft carrier and are not invested in war-winning strategies.⁴² Discussions and efforts to change the naval force through carrier reductions to fund alternative and likely more relevant and effective capabilities, like submarines, are met with stiff political resistance.⁴³ If an adversary is aware of the herculean efforts the Navy will undertake to protect its most prized assets, then it has identified an exploitable vulnerability. Their assumptions and investments in fielding anti-carrier systems are correct and will always be cheaper and easier to deploy than the platform they target.

In chess, the objective is to capture the opponent’s King, not protect its queen at all costs. But there is evidence that is exactly what is occurring.⁴⁴ Naval planners appear unwilling to consider a role for the carrier as anything other than the main effort of any naval campaign.⁴⁵ Such closed-mindedness is unlikely to result in lucky outcomes, but rather short-sighted and costly sacrifices.

Japan’s decision to use its carriers as diversions was in accordance with Magruder’s Principle and preyed directly upon Halsey’s psyche. Before discovering the Japanese carriers, Halsey remarked, “If this was to be an all-out attack by the Japanese fleet [referring to attempts to disrupt the Leyte landings], there was one piece missing from the puzzle – the carriers.”⁴⁶ While Campaign Plan Granite and Nimitz’s orders prioritized the destruction of the Japanese fleet, Halsey, ultimately pursued because these were important pieces – important because carriers were important to him.⁴⁷ Admiral Kurita ultimately made the same mistake and shifted his focus toward the escort carriers that were near the path to his main objective because he mistook them for fleet carriers. Subsequently entranced by his own carrier target fixation, even when there was abundant evidence that he was not facing fleet carriers, Kurita wasted his opportunity to exploit the decisive opening the Japanese decoy carriers had created for him.

Winning is the main objective, not forcing a use case that does not conform to reality. To outsmart your opponent, one must first know how that opponent perceives your centers of gravity. U.S. narratives, writings, and real-world operations extolling the importance of aircraft carriers do much to reinforce the perception that these queens are the U.S. Navy’s prized possessions and that they will be the main effort for any coming maritime war. Navy commanders should be ready to exercise a break with precedent to exploit this narrative by entertaining the idea that the carrier might be better suited for other roles, especially as a decoy force. If not, they risk falling victim to their own mythology.

References

[1] Nimitz’s Gray Book. Pg. 2246. Messages from CTF 77 began coming in on October 24^th at 2207. At 2235, messages grew more desperate, “Under attack.” By 2239, CTF 77 made a desperate plea to Halsey, “Fast battleships are urgently needed immediately at Leyte Gulf.” At 2329, CTF 77 once again radioed Halsey, “My situation is critical.” At 0044, Nimitz sends Halsey the fateful message, “Where is task force 34?”

[2] C. Vann Woodward. “The Battle for Leyte Gulf,” Skyhorse Publishing, Inc. 2017.

[3] No Author. “Chess Terms: Queen Sacrifice,” Chess.com, No date. (Accessed May 19^th, 2023)

[4] Gerry Doyle & Blake Herzinger. “Carrier Killer: China’s Anti-Ship Ballistic Missiles and Theater of Operations in early 21^st Century,” 2022. Pg. 39.

[5] Brad Lendon and Haley Britzky. “US can’t keep up with China’s warship building, Navy Secretary says,” CNN Online. February 22, 2023. (Accessed May 19^th, 2023)

[6] Dr. Jerry Hendrix. “Retreat from Range: The Rise and Fall of Carrier Aviation,” Center for a New American Security, October 2015. Pg. 51.

[7] I Cutis Utz. “Fleet Problem IX: January 1929,” Naval History and Heritage Command, no date. (Accessed May 20^th, 2023)

[8] Ibid.

[9] Scot MacDonald. “Evolution of Aircraft Carriers: The last of the Fleet Problems,” National Museum of the U.S. Navy, accessed August 28^th, 2023. (history.navy.mil) Pg. 36

[10] Thomas G. Mahnken. “The Cruise Missile Challenge,” Center for Strategic and Budgetary Analysis, 2005. Pg. 12-13.

[11] No Author. “Loss of USS Wasp,” “Loss of the USS Block Island,” “USS Yorktown,” “The Sinking of the USS Liscome Bay,” National Museum of the U.S. Navy, accessed August 6^th, 2023. (https://www.history.navy.mil)

[12] William P. Gruner. “U.S. Pacific Submarines in World War II,” Reprinted by the San Francisco Maritime National Park Association, Accessed August 6^th, 2023. (https://maritime.org/doc/subsinpacific.php#pg6)

[13] No Author. “Naval-History.Net,” Accessed August 6^th, 2023. (https://www.naval-history.net/WW2aBritishLosses02CV.htm)

[14] No Author. “Loss of USS Bismarck Sea,” “Loss of the USS St. Lo,” “USS Ommaney Bay,” National Museum of the U.S. Navy, accessed August 6^th, 2023. (https://www.history.navy.mil)

[15] Chris Hobson and Andrew Noble, Falklands Air War (Hinckley, UK: Midland Publishing, 2002), 157–58; John Lehmann, “Reflections on the Special Relationship,” Naval History 26, no. 5 (September 2012).

[16] Andrea Gilli, Mauro Gilli, Antonio Ricchi, Aniello Russo, and Sandro Carniel. “Climate Change and Military Power: Hunting for Submarines in the Warming Ocean,” Texas National Security Review 7, no. 2 (Spring 2024): 16-41. https://doi.org/10.26153/tsw/52240.

[17] Craig Hooper. “The Navy Is Ill-Equipped to Come to the Rescue,” Forbes, February 28^th, 2023. https://www.forbes.com/sites/craighooper/2023/02/28/when-an-american-carrier-needs-help-what-will-us-navy-do/

[18] Dana Priest & Judith Havemann. “Second Group of U.S. Ships Sent to Taiwan,” The Washington Post, March 11^th, 1996.

[19] Kristen Gunness and Phillips C. Saunders. “Averting Escalation and Avoiding War: Lessons from the 1995-1996 Taiwan Strait Crisis,” China Strategic Perspectives, December 2022. Pg. 23.

[20] David Lague & Maryanne Murray. “War Games T-Day: The Battle for Taiwan,” Reuters, November 5^th, 2021.

[21] Gerry Doyle & Blake Herzinger. “Carrier Killer: China’s Anti-Ship Ballistic Missiles and Theater of Operations in early 21^st Century,” 2022. Pg. 12, 29, & 35.

[22] Dr. Jerry Hendrix. “Retreat from Range: The Rise and Fall of Carrier Aviation,” Center for a New American Security, October 2015. Pg. 51.

[23] Gerry Doyle & Blake Herzinger. “Carrier Killer: China’s Anti-Ship Ballistic Missiles and Theater of Operations in early 21^st Century,” 2022. Pg. 35.

[24] Henk H.F. Smid. “An Analysis of Chinese Remote Sensing Satellites,” The Space Review, September 26^th, 2022. https://www.thespacereview.com/article/4453/1

[25] No author. “Project 2319 Tianbo [Sky Wave] Over-the-Horizon Backscatter Radar [OTH-B],” Global Security Organization, No Date. (Accessed May 24^th, 2023) https://www.globalsecurity.org/wmd/world/china/oth-b.htm

[26] Alastair Luft. “The OODA Loop and the Half-Beat,” The Strategy Bridge, March 17^th, 2020. https://thestrategybridge.org/the-bridge/2020/3/17/the-ooda-loop-and-the-half-beat

[27] Alex Hern. “Computers now better than humans at recognizing and sorting images,” Guardian, May 13^th, 2015.

[28] Yuan-Chou Jing. “How Does China Aim to Use AI in Warfare,” The Diplomat, December 28^th, 2021. https://thediplomat.com/2021/12/how-does-china-aim-to-use-ai-in-warfare/

[29] Based on an interview with Laruen Kahn, an artificial intelligence researcher and a policy advisor at Force Development and Emerging Capabilities at the Department of Defense.

[30] Annie Brown. “Biased Algorithms Learn From Biased Data: 3 Kinds of Biases Found in AI Datasets,” Forbes, February 7^th, 2020. (https://www.forbes.com/sites/cognitiveworld/2020/02/07/biased-algorithms/?sh=19897ab76fc5).

[31] Lauren Leffer. “Humans Absorb Bias from AI – And Keep It after They Stop Using the Algorithm,” Scientific American, October 26^th, 2023. https://www.scientificamerican.com/article/humans-absorb-bias-from-ai-and-keep-it-after-they-stop-using-the-algorithm/#:~:text=She%20cites%20a%20recent%20assessment,tools%20than%20to%20other%20sources.

[32] The Battle of the Philippine Sea devastated the Imperial Japanese Navy’s pilot cadre. Unable to train pilots fast enough, the decision was made to use the Japanese carriers as diversions, and carrier aircraft would be flown off to be land-based. Meanwhile, US commanders were frustrated that Japan’s carrier force was left relatively intact after the battle and still assumed them to be threats.

[33] Sam LaGrone. “Camouflaged Ships: An Illustrated History,” U.S. Naval Institute News, March 1^st, 2013.

[34] Mia Jankowicz. “Russia is painting dark strikes on its warships to make them look smaller and confuse Ukrainian drones, says expert,” Business Insider, July 5^th, 2023. (https://www.businessinsider.com/russia-warships-paint-camouflage-confuse-ukrainian-drones-usvs-2023-7)

[35] Miriam Bibby. “Britain’s WWI Mystery Q-Ships,” The History and Heritage Accommodation Guide, No date. (Accessed May 28^th, 2023)

[36] Gary Anderson. “How Navy Decoy Drones Could Thwart China’s War Strategy in the Pacific,” Military.com, September 6^th, 2022.

[37] Andrew Higgins, “Russian Troops in Belarus Spur Debate Over the Threat to Ukraine,” New York Times, October 21, 2022, https://www.nytimes.com/2022/10/21/world/europe/ukraine-belarus-russian-troops.html

[38] Donald P. Wright. “Deception in the Desert: Deceiving Iraq in Operation DESERT STORM,” Army University Press, 2018.

[39] Trent Hone. “Countering the Kamikaze,” Naval History Magazine Vol. 34, No. 5, October 2020.

[40] Lieutenant Commander Jeff Vandenengel, USN. “100,000 Tons of Inertia,” Proceedings Vol. 146/5/1407, May 2020.

[41] Lieutenant Commanders Collin Fox & Dylan Phillips-Levine, USN. “Launch Big Missiles from Big Ships,” Proceedings Vol. 149/1/1439, January 2023.

[42] Jerry Hendrix. “The U.S. Navy Needs to Radically Reassess How it Projects Power,” The National Review, April 23^rd, 2015. https://www.nationalreview.com/2015/04/age-aircraft-carrier-over-jerry-hendrix/

[43] David Axe. “This U.S. Navy Aircraft Carrier Won’t Be Headed to the Scrapper,” The National Interest, March 3^rd, 2019.

[44] Gerry Doyle & Blake Herzinger. “Carrier Killer: China’s Anti-Ship Ballistic Missiles and Theater of Operations in early 21^st Century,” 2022. Pg. 10.

[45] Dr. R. B. Watts. “The Wrong Lessons from a Century of Conflict,” Modern War Institute, February 15, 2022.

[46] C. Vann Woodward. “The Battle for Leyte Gulf,” Skyhorse Publishing, Inc. 2017. Pg. 41.

[47] No Author. “Campaign Plan Granite,” Pg. 2.

Featured Image: South China Sea (Oct. 9, 2019) Multiple aircraft from Carrier Air Wing (CVW) 5 fly in formation over the Navy’s forward-deployed aircraft carrier USS Ronald Reagan (CVN 76). (U.S. Navy photo by Mass Communication Specialist 2nd Class Kaila V. Peters/Released)

By George Galdorisi

At no time since the end of World War II have so many nations fielded blue water navies that have roamed the globe. Navies from Australia, China, Japan, Russia, the United Kingdom, and the United States have regional and worldwide commitments. Whether it is reinforcing or challenging rules-based order at sea, showing resolve to reassure allies and deter rivals, or exercising with other navies, these fleet also recognize that they must be prepared for high-end war at sea. Comparative naval advantage has returned as a critical unit of measure in great power competition.

But despite growing threats, navies have become accustomed to traversing the oceans and littorals with near impunity. This ability is now being increasingly jeopardized, and not necessarily by conventional high-end threats. For centuries, sea mines have presented an affordable and effective option in naval warfare. That threat is increasing today. The number of countries with mines, mining assets, mine manufacturing capabilities, and the intention to export mines has grown dramatically over the past several decades. More than fifty countries possess mines and mining capability. Of these, thirty countries have demonstrated an indigenous mine production capability and twenty have attempted to export these weapons. Additionally, non-state actors have used these cheap and plentiful weapons to hazard commercial vessels and disrupt commerce on the oceans.

When policymakers, military leaders, and analysts compare the qualities of various navies, they typically think in terms of numbers of ships, submarines, aircraft, and other conventional assets. However, considering the growing threat of sea mines worldwide, the capability to employ and defeat mines forms another core consideration in gauging the balance of naval advantage. Navies must consider how to field affordable and risk-worthy unmanned systems at scale to meet the mine threat.

A Centuries Old Challenge

Mine warfare is not new. Precursors to naval mines were first invented by innovators of Imperial China. The first plan for a sea mine in the West was drawn up by Ralph Rabbards, who presented his design to Queen Elizabeth I of England in 1574. Since the invention of the Bushnell Keg in 1776 (a watertight keg filled with gunpowder that was floated toward the enemy, detonated by a sparking mechanism if it struck a ship), mine warfare has been an important element of naval warfare.¹ While the first attempt to deliver the Bushnell Keg from America’s first combat submarine, the Turtle, against a British warship in 1776 failed, subsequent attempts to employ these early mines were successful.²

Over 150 years ago, Admiral David Farragut became famous for “damning torpedoes” (which were actually mines) at the entrance to Mobile Bay during the Civil War.³ Indeed, in the early stages of the Civil War, Admiral Farragut wrote to Secretary of the Navy Gideon Welles about the sea mine threat posed by the Confederacy, stating, “I have always deemed it unworthy of a chivalrous nation, but it does not do to give your enemy such a decided superiority over you.” Farragut’s warning was eerily prescient. ⁴

The use of sea mines and countermeasures to these weapons have figured significantly in every major war and nearly every regional conflict in which the United States has been involved since the Revolutionary War. Indeed, the naval mine has been a mainstay of modern warfare. The North Sea Mine Barrage, a large minefield laid by the U.S. Navy and Royal Navy between Scotland and Norway during World War I, inhibited the movement of the German U-boat fleet. During World War I more than one thousand merchant ships and warships were lost because of the 230,000 mines used.⁵ NATO navies continue to clear these mines to this day.⁶

Mines released by U.S. Navy submarines and dropped by U.S. Army Air Force B-29 bombers in the Western Pacific during World War II sank hundreds of Japanese warships, merchant ships, and smaller vessels. During World War II 2,665 ships were lost or damaged by 100,000 offensive mines.⁷

In Korea during the early 1950s, the Soviets provided North Korea with thousands of sea mines. These were used to defend key harbors and multiple U.S. warships struck mines. During the Vietnam War, over 300,000 American naval mines were used. In 1972 Haiphong Harbor was seeded with 11,000 destructor mines and was shut down completely for months, and it took years to clear out all the American mines.⁸

In the past several decades, rogue states have indiscriminately employed sea mines. Libya used mines to disrupt commerce in the Gulf of Suez and the Strait of Bab el Mandeb. In the 1980s Iran laid mines to hazard military and commercial traffic in the Arabian Gulf and Gulf of Oman, leading to the devastating mine strike against USS Samuel B. Roberts (FFG 58). During Operation Desert Storm in 1990-1991, the threat of mines precluded the effective use of the Navy and Marine Corps expeditionary task force off Kuwait and hazarded all U.S. and coalition forces operating in the Arabian Gulf. Indeed, Operation Desert Storm highlighted the importance of mine warfare with the heavy damage dealt to USS Princeton (CG 59) and USS Tripoli (LPH 10). The U.S. Navy has an abundant history of employing mines and striking them, but it remains unclear what the U.S. Navy’s mine strategy is for modern naval warfare.

Today’s Ongoing Mine Challenge

Mine warfare remains a critical element of naval capability. In terms of availability, variety, affordability, ease of deployment, and potential impact on naval operations, mines are some of the most attractive weapons available.

Sea mines are hard to find, difficult to neutralize, and can present a deadly hazard to any vessel—especially those ships specifically designed to hunt them. They can also heavily shape behavior and weigh on the operational calculus of commanders, making them a source of potent psychological effects in the battlespace. 

Great power rivals are likely to employ mines in any conflict with the United States. Scott Truver highlighted the danger posed by China’s mine warfare capabilities, as well as those of other potentially hostile nations:

“The mine warfare experiences of America and other nations are not lost on the People’s Liberation Army Navy (PLAN). Chinese naval analysts and historians understand the asymmetric potential for mine warfare to baffle the enemy, and thus achieve exceptional combat results.’ Mines provide what some have described as affordable security via asymmetric means.”⁹

Seth Cropsey echoed similar challenges and highlighted the mining capabilities China and Russia would bring to the fight. He focused primarily on the threat from China, noting:

“One of the top global mine threats comes from China. It has been estimated that Beijing has as many as 100,000 such weapons. Those range from the old-fashioned moored contact mine to include mines that have rocket-propelled weapons and target detection systems. In the event of a conflict with China, the United States is unlikely to approach warfare from the land. That leaves us with the seas as the place where conflict is most likely to play out.

Beijing would likely concentrate on creating choke points in areas such as the archipelagos that separate East Asia from the Middle East and the South China Sea. That means that sea control and navigating around China’s anti-access and area denial capabilities will be crucial. It’s reasonable to expect that the Chinese would use mines there, and reasonable to expect that they would use mines if they decided to use force against Taiwan. Moving through those straits is crucial and being able to clear them of mines is equally important.”¹⁰

The danger of naval mines being employed short of major war is acute in the Middle East. In October 2020, a Maltese-flagged tanker was damaged by a mine while taking on crude oil the Yemeni port of Bir Ali. MV Syra reportedly suffered significant damage, resulting in an oil spill.¹¹ Shortly after this event, in November 2020, a mine in the Red Sea exploded and damaged a Greek oil tanker.¹² In December 2020, a Singapore-flagged tanker berthed at the Saudi Arabian port city of Jeddah was damaged by a mine, with Houthi militia from Yemen strongly linked to this attack.¹³ In January 2021, an oil tanker off the coast of Iraq discovered a mine attached to its hull.¹⁴ Regional navies, assisted by U.S. and U.K. navies, have stepped up mine countermeasures exercises in the Arabian Gulf.¹⁵ Most recently, France, the United Kingdom, and the United States conducted the Artemis Trident MCM Exercise in Arabian Gulf.¹⁶

As part of the 2022 Russian invasion of Ukraine, Russia mined the waters off the Crimean Peninsula. Some of those mines either broke loose or were cut loose and drifted into shipping lanes used by Ukrainian and NATO ships.¹⁷ Russia has continued to use sea mines extensively during the conflict in Ukraine. One of the most prominent examples involved Russian forces laying mines along the Dnieper River to the north of Kherson city to make it harder for the Ukrainians to cross.¹⁸

Other incidents have included Russian drifting mines that have been found along the coasts of Turkey and Romania, as well as elsewhere in the Black Sea. An Estonian cargo ship in the Black Sea was sunk by a Russian mine during this war.¹⁹ More recently, in February 2023, Turkish media claimed that a drifting sea mine exploded near Agva on the Black Sea coast.²⁰

The ability of the U.S. Navy to deal with the growing threat of sea mines is not getting better, it is getting worse. The platforms that embody the U.S. Navy’s primary mine countermeasures (MCM) capability—the MH-53E AMCM aircraft and the Avenger-class minesweeper—are scheduled to retire in the next few years, which will leave the totality of the Navy’s MCM capability in the discrete number of Littoral Combat Ships (LCS) to be outfitted with the Mine Countermeasures mission package, which has suffered multiple delays during testing and development.

This is not the MCM capability needed by a global navy facing a pervasive mine threat. Nor is it a solution that eliminates the extreme danger to Sailors who are forced to work in a minefield to accomplish their mission, especially when the minefield is overlayed with the advanced anti-ship and anti-air capabilities of a great power adversary. Fortunately, technology has advanced to the point that with the proper commitment the Navy can conduct MCM remotely by leveraging unmanned systems and take the Sailor out of the minefield.

Leveraging Unmanned Technologies to Defeat Deadly Sea Mines

For all navies, there is only one way to completely take the Sailor out of the minefield and that is to leverage unmanned technologies to hunt and destroy mines from a distance. While this principle is readily acknowledged, it is not a lack of need that has impeded the Navy’s efforts, but rather technological maturity. In the past, unmanned vehicle technologies were not mature enough to take on the complex task of mine hunting. But today, they are now capable enough. These capabilities are no longer based on concepts or early prototypes. Rather, every necessary component has been in the water and tested in operational environments. 

The following proposal is based on three subcomponent candidates that can deliver a single-sortie, autonomous mine countermeasures solution with autonomous target recognition. This design can also flexibly accommodate various towed sonars and remotely operated vehicles (ROVs).

The MARTAC Devil Ray T38 is intended as the autonomous platform for the package, and will host a communications and data transmission hub, in addition to above-water and underwater sensors.

The ThayerMahan Sea Scout Subsea Imaging System is specifically designed for missions such as mine hunting. The Sea Scout system is based on the in-production COTS Kraken Robotics Katfish-180 tow-body mounted synthetic aperture sonar. The system is designed to search for mine-like objects and is integrated by ThayerMahan’s remote operations and communications system.

The Pluto Gigas is an existing, standalone, third generation ROV with several systems deployed globally and with over 3,000 mines destroyed. The Pluto Gigas deploys an acoustically armed and detonated countermine charge that is low-cost both in production and in logistics and sustainment. Several charges can be loaded onto the T38 to enable single-sortie field clearance.

These three components can combine to deliver an effective mine hunting solution. The driving principle of this solution is to incorporate mature hardware that will minimize risk to the host platform during execution of the MCM mission. To that end, the weight and outside dimensions of the mission package are within a few inches of the dimensions of a common 11-meter RHIB. Launch and recovery should be easily accomplished using standard naval small craft handling procedures for the host vessel.

While this MCM solution is component agnostic, the leading commercial-off-the-shelf candidates for the initial solution were chosen based on their technical maturity, as well as their current use by various navies. Leveraging these commercial-off-the-shelf (COTS) systems will enable this MCM solution to move forward at an accelerated pace to speedily deliver a fleet capability in the near term.

The Need to Take Action Today to Address the MCM Challenge 

Because ships and Sailors operate daily in harm’s way, the U.S. Navy and Marine Corps—and by extension other allied navies—would be well-served to accelerate their efforts to deal with deadly sea mines. The essential components for such a system exist today, and a robust COTS MCM solution can reach fruition in the near-term.

While programs of record are developing next-generation technology, navies should invest in parallel-path solutions that leverage mature subsystems that are ready to provide capability today. It is time to put a speedy solution in the hands of Sailors.

To achieve victory, navies must get to the fight in the face of anti-access area denial capabilities of adversaries. Given the low cost, ease of deployment, and increasing proliferation of naval mines, the ability to find and clear these deadly mines makes for a major pacing challenge for navies. Developing and fielding mine countermeasures capabilities, overlooked for too long, should be a first order priority for navies today.

Captain George Galdorisi is a career naval aviator and national security professional. His 30-year career as a naval aviator culminated in 14 years of consecutive service as executive officer, commanding officer, commodore, and chief of staff. He enjoys writing, especially speculative fiction about the future of warfare. He is the author of 18 books, including four consecutive New York Times bestsellers. His latest book, published by the U.S. Naval Institute, is Algorithms of Armageddon: The Impact of Artificial Intelligence on Future Wars.

References

[1] Tyler Rogoway, “The Revolutionary War Gave Birth to the Age of Naval Mine Warfare,” The War Zone, July 4, 2016, accessed at: https://www.thedrive.com/the-war-zone/4256/the-revolutionary-war-gave-birth-to-the-age-of-naval-mine-warfare.

[2] Christopher Hevey and Anthony Pollman, “Reimagine Offensive Mining, U.S. Naval Institute Proceedings, January 2021.

[3] Farragut’s boldness is especially striking because in 1862 a Confederate mine sank USS Cairo in the Yazoo River.

[4] U.S. Navy Fact File, “U.S. Navy Mines,” accessed at: https://www.navy.mil/Resources/Fact-Files/Display-FactFiles/Article/2167942/us-navy-mines/.

[5] See, for example, Paul Ahn, “A Tale of Two Straits,” U.S. Naval Institute Naval History Magazine, December 2020 for a concise history of naval mine warfare.

[6] “NATO Forces Clear Mines off Port of Dieppe,” The Maritime Executive, April 9, 2020, accessed at: https://www.maritime-executive.com/editorials/royal-navy-clears-mines-off-port-of-dieppe.

[7] US Navy Fact File, “US Navy Mines,” accessed at https://www.navy.mil/navydata/fact_display.asp?cid=2100&tid=1200&ct=2).

[8] “Surface Forces: Mines Revisited,” Strategy Page, March 13, 2020, accessed at: https://www.strategypage.com/htmw/htsurf/articles/20200313.aspx

[9] Scott Truver, “Taking Mines Seriously: Mine Warfare in China’s Near Seas,” Naval War College Review, Spring 2012, accessed at:

https://digital-commons.usnwc.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=1429&context=nwc-review.

[10] Yasmin Tadjdeh, “Navy Invests in New Mine Warfare Technology,” National Defense Magazine (online), April 6, 2020, accessed at: https://www.nationaldefensemagazine.org/articles/2020/4/6/navy-invests-in-new-mine-warfare-technology.

[11] Edward Lundquist, “Tanker Loading Crude Damaged by Floating Mine in Yemen,” Seapower, October 9, 2020, accessed at: https://seapowermagazine.org/tanker-loading-crude-damaged-by-floating-mine-in-yemen/.

[12] Ryan White, “Greek-Operated Tanker Damaged by Mine at Saudi Terminal,” Naval News, November 25, 2020, accessed at: https://navalnews.net/greek-operated-tanker-damaged-by-mine-at-saudi-terminal/.

[13] Sam Chambers, “Hafnia Tanker at Jeddah Becomes Latest Mine Victim,” Splash 247.com, December 14, 2020, accessed at: https://splash247.com/hafnia-tanker-at-jeddah-becomes-latest-mine-victim/.

[14] “Oil Tanker Near Iraq Finds Mine on Hull as Gulf Risks Mount,” Newsmax, January 4, 2021, accessed at: https://www.newsmax.com/newsfront/cos-exe-gen-gov/2021/01/01/id/1003892/.

[15] “Saudi, UK, U.S. Naval Forces Conduct Mine Countermeasures Training,” Defense-Aerospace, November 29, 2020, accessed at: https://www.defense-aerospace.com/articles-view/release/3/214552/saudi%2C-uk%2C-u.s.-naval-forces-conduct-mine-countermeasures-training.html.

[16] Naval News Staff, “U.S. France and UK Complete Artemis Trident MCM Exercise in Gulf,” Naval News, April 13, 2023.

[17] “Weapons: Naval Mines in The Black Sea,” Strategy Page, February 2, 2023, accessed at: https://www.strategypage.com/htmw/htweap/articles/20230202.aspx.

[18] Gerrard Kaonga, “Russia Mines River as Soldiers Prepare Kherson Retreat: Kyiv,” Newsweek, October 25, 2002.

[19] Scott Savitz, “The Drifting Menace,” Real Clear Defense, (undated), accessed at: https://www.realcleardefense.com/articles/2022/11/16/the_drifting_menace_865111.html.

[20] Tayfun Ozberk, “Sea Mine Explodes on Turkey’s Black Sea Coast,” Naval News, February 14, 2023.

Featured Image: An unmanned surface vehicle is craned aboard the Independence-variant littoral combat ship USS Canberra (LCS 30), as a part of the first embarkation of the Mine Countermeasures (MCM) mission package. (U.S. Navy photo by Mass Communication Specialist 1st Class Vance Hand)

By Brent D. Sadler

June 2024 marks the 90^th year since commissioning the Ranger (CV-4), the first purpose-designed and built U.S. aircraft carrier. The Ranger stood on the legacies of several ships, most notably the converted collier Langley (CV-1), commissioned in 1922. A century of lessons learned from fleet experimentation during the interwar period, wartime experiences from World War Two, and the necessities of nuclear deterrence during the Cold War coalesced into today’s premier aircraft carrier, the Ford (CVN-78). 

This legacy is more than just the evolution of the aircraft carrier as a ship; it represents a complex interaction between aircraft design, operational requirements driven by the battle space, and technology like nuclear propulsion. That said, there are consistencies throughout the evolution of the aircraft carrier: the importance of sortie rates, the advantage of longer operational range (for aircraft and ships), sensor coverage (to include scouting aircraft), and secure communications. As such, American aircraft carriers persevered over the challenge of Imperial Japan’s Kamikaze attacks, Soviet bomber long-range anti-ship cruise missiles, and will likely again over China’s anti-ship ballistic missiles. The bottom line is that the threats are not new, but how the carrier and its airwing evolve will determine its future. Contemporary nuclear-powered supercarriers, like the Ford, are built with a service life of 50 years, a timeframe equal to half the period aircraft carriers existed.

Today, the aircraft carrier faces evolving challenges and emerging technological opportunities. Amidst these challenging times, there is no single or clear picture of how these warships and their airwings will best perform in a modern blue-water war. However, with the next major war shaping up to be a modern replay of the last war in the Pacific, geography shows it is highly likely the aircraft carrier will play a leading role again, but not in traditional battle or strike group formations.

The fifty-year dilemma of today’s aircraft carriers and airwings is how to embrace various technological developments in unmanned platforms, long-range weapons, and new methods of processing massive amounts of targeting data. Wartime experience in the Pacific clarifies that getting this right is never assured. Building flexibility and adaptability is paramount for today’s aircraft carriers and airwing.

Introduction

Aircraft carrier design is based on a simple premise: launching, recovering, and sustaining aircraft at sea. In addition, a range of naval missions—strike, air defense, and submarine detection—influence naval aircraft design and inform carrier design and operations. It is an iterative process with successes and failures littered throughout the century of aircraft carriers’ existence.

Today, as historically, there are technologies weighing on the aircraft carrier and its airwing. For example, weapon systems can hold the aircraft carrier and its airwing at risk well outside its organic sensors and weapons range. Top of the threat list is the much-hyped Chinese anti-ship ballistic missile (e.g., DF-21, DF-26) with a range of more than 3,000 miles. These weapons were in steady development for almost 20 years, building on a similar Soviet weapon system of the Cold War. Today, the Houthis are employing anti-ship ballistic missiles to limited effect in the Red Sea, and China’s military is certainly taking note to improve its designs and operational concepts. Chinese air-to-air weapons outrange today’s U.S. airwings with anti-air missiles like the PL-15 or newer PL-17, with ranges of around 186 miles, and exacerbate kinematic shortcomings. Importantly, weapons’ range is only effective if fed with precise targeting. Weapon evolution is nothing new, and the carriers and their airwings evolved to overcome such threats in the past. For example, the AIM-54C “Phoenix” air-to-air missile was developed to defeat Soviet Backfire bombers before reaching its weapons’ launch range against the carriers.

The ability to make sense of massive amounts of networked sensor data is rapidly evolving for attack and defense. Effectively placing a weapon on a target hundreds of miles away or defending against such an attack is a team effort. Vital to success is the ability to reliably connect various platforms and sensors across hundreds of miles and rapidly process copious data. The key to these efforts is artificial intelligence and big data management systems to focus and speed up human decision-making. Networking the naval and even proximate land and space assets together is widely recognized as fundamental to success on the battlefield today and well into the future. Thus, it will be a key element of future carriers and their airwings.

A January 2024 Paris naval conference focused on how these forces will shape U.S. and allied navies’ next-generation aircraft carriers and naval airwings. For the host, the impending decision by the French Navy to determine the requirements for its next aircraft carrier loomed over many of the panels’ discussions.¹ The U.S. Chief of Naval Operations reflected on 100 years of U.S. aircraft carrier experience: “…one thing that you really see from carrier aviation and carrier strike groups is their adaptability.” The theme resonated throughout the conference and was echoed in the over 40 submitted papers for review, which informed the event’s numerous panels. Adaptability is a common feature of successful warship designs in naval warfare. The history of the aircraft carrier, its airwing, and associated escort ships’ success is a testament to the persistent value of adaptability.

Aircraft carriers are a significant investment, costing over $13B and requiring a highly trained crew numbering in the thousands. As such, aircraft carriers are built to last 50 years and so must be adaptable. Fifty years ago, the U.S. Global Positioning System or networked fleet units did not exist. Today’s buzz concerns a fourth industrial revolution centered on quantum computing and artificial intelligence. Technology moves fast, and being adaptable is the only way to be ready. The best way to maintain adaptability in a naval warship is with ample space and excess power generation. Observers noted that after advanced electronic warfare systems modification, the Arleigh-Burke class Pinckney sported significant bulges on its superstructure to carry the added gear and new power systems that did not fit into the already full ship.²

Milestones in Aircraft Carrier and Airwing Design

The evolution of the aircraft carrier and its airwing can be boiled down into three evolutionary periods: creation, experimentation, and adaptation. Importantly, adaptation can be broken down into two periods: wartime, notably in the Pacific, and the Cold War. Finally, a fourth era, which arguably we are in today, could be called tessellation or the covering of a space without gaps. Before diving into what tessellation implies for the future of the aircraft carrier and its airwing, a brief overview of the earlier evolutionary periods is informative.

The Age of Creation

The evolution of the aircraft carrier shortly followed aircraft entering the battlefield. For the U.S. Navy, the origin story of the aircraft carrier began with the successful takeoff and landing on an improvised at-sea platform by a plane piloted by Eugene Ely. In 1912, the first U.S. naval aviation unit was established. By 1914, the naval aviation unit was connected to the warships’ command and control network with the adoption of radio.³ However, it would be the U.K.’s improvisation to fight the First World War’s German submarine threat that saw the first viable aircraft carriers put to sea.

The first true aircraft carrier to enter service was the British warship Argus, a repurposed Italian cruise liner whose construction was halted in 1916. The Argus was put to sea in 1918, and it was too late to see combat, but its impact on Japanese and American navies was immense. Three design issues surfaced in this first aircraft carrier: speed, stability, and obstruction to flight operations from the exhaust stacks. In the case of Argus, modifications to the initially very stable cruise liner made the ship top-heavy and prone to rolls that imperiled flight operations. Smoke and physical obstruction from the exhaust stacks were remedied by placing them under the flight deck and aft. This was not a perfect solution, but it was workable. This solution also helped the third challenge, speed. For the underpowered airplanes of the day, wind speed over the flight deck to takeoff required a ship’s speed of 30 to 35 knots. Early wind tunnel studies showed that if the exhaust stacks had been above the flight deck, it would have caused unacceptable amounts of cross-deck turbulence. In 1918, flight trials were conducted with a canvas dummy island installed. With an island structure, the pilots found it easier to judge distances on landing.⁴ Many of these lessons informed the next era in aircraft carrier and airwing development.

The Age of Experimentation

1922 marked the beginning of a nearly 20-year process of experimentation and design improvements to the aircraft carrier and its airwing. That year, the Langley (CV-1) entered service as the first U.S. aircraft carrier after a two-year conversion from a collier. She became a test platform for naval aircraft carriers and airwing operations until her conversion to a seaplane tender in 1937, as a war in the Pacific loomed. During this timeframe, she was joined by the much larger converted cruisers Lexington and Saratoga. Through a series of major naval exercises called “Fleet Problems,” the Navy experimented with various operational approaches. Through the 1920s, the Navy learned that the larger aircraft carriers afforded stability, which enabled flight operations in rough seas. The Navy also realized the value of the aircraft catapult, the importance of open hangers for rapid aircraft readying, and the need to focus on sortie rate.⁵  The lessons learned from these three warships informed the first purpose-built aircraft carrier, the Ranger.

Ratified in 1922, the Washington Treaty ratified constrained naval construction by tonnage for the world powers. The treaty made naval aviation and aircraft carriers an attractive and powerful addition to the fleet for less tonnage. The Ranger design incorporated the lessons of the 1920s when it was commissioned in 1934. Originally designed with a flush deck like the Langley, an island superstructure was later added while being built to aid in flight operations, direct defensive weapons, and navigate the ship. The Ranger’s naval designers required an endurance of 10,000 miles to support long-range operations in the Pacific. War plans anticipated in the 1930s that American possessions, the Philippines and Guam, would be cut off in any war with Japan, with naval forces having to fight their way across the Pacific. During the design phase, consideration of aircraft accommodation, like deck weight constraints or catapult design limitations, weighed heavily on the Ranger’s final specifications. These considerations included compatibility with a 10,000-pound bomber with a flight deck of 665 feet.

Light cruisers, notably the New Orleans-class and the Benson-class destroyers, would eventually play a key role in supporting aircraft carrier air defenses. The Navy realized from the Fleet Problems by 1930 that surface warships, including the aircraft carrier, were susceptible to air attack, which resulted in efforts to improve air defenses at sea. Fleet Problem IX in 1929 was a watershed event; it demonstrated the value of independent carrier operations relying on the speed and range of its striking airwing while exposed to shore-based threats.⁶ Nonetheless, the too-short range of then naval aircraft and a too-modest speed advantage against surface warships meant the Navy’s early carriers were vulnerable. Eventually, this led to purpose-built escorts filling the air defense mission, mitigating the need for defenses on the aircraft carrier and freeing deck space and tonnage for more aircraft.

By 1930, the Navy considered operating heavier naval aircraft with greater range from carriers. This required greater strength of the flight deck, catapults for launching, stronger arresting gear for landings, larger hangars and elevators to move aircraft to the flight deck, and other design improvements. The airwing of the early 1930s consisted of 18 heavy-attack bombers, 12 scout planes, and 2 squadrons (36 planes) of fighters. The next generation of aircraft carriers, the Yorktown-class, was planned to carry four 18-plane squadrons, with various proposals that included dive-bombers with 1,000 payloads and fighter-bombers. All variations of the next airwing included long-range scouts, which were critical to spotting enemy fleets and launching attacks before the enemy. To accommodate the future airwing, the Yorktown-class aircraft carriers grew from Ranger’s 16,140 tons to well over 20,000 tons. The three carriers of this class played critical roles early in the Pacific theater of World War II. Yorktown was lost at the Battle of Midway, Hornet at the Battle of the Santa Cruz Islands, and Enterprise survived the war. These three aircraft carriers provided important wartime lessons that continue to inform aircraft carrier and naval aviation designs today.

Adaptation – Wartime

The Atlantic theater of World War II differed from the long-range naval operations conducted in the Pacific. As such, the theater demands on the carrier and its airwing were incongruous, contributing to the Navy’s decision to send the operationally limited Ranger from the Pacific to service in the Atlantic. The Ranger ultimately served in the November 1942 invasion of North Africa in Operation Torch and attacked German shipping along the Norwegian coast in October 1943 in Operation Leader.⁷ The larger legacy carriers, Lexington and Saratoga, were retained in the Pacific and saw action early in the war. In the Pacific, operational range and striking power were paramount, correlated to the fuel carried onboard and the ability to sustain a large airwing.

Critically, the larger Lexington and Saratoga were able to operate the heavier new aircraft entering service in the late 1930s. Size and catapults mattered in ensuring an aircraft carrier could adapt to new aircraft. Wartime experience, especially during late-war countermeasures against Japanese Kamikaze suicide attacks, validated the expansion of air defenses and dedicated escorts. The loss of the Hornet and damage to the aircraft carrier Intrepid, both Essex-class, underscored the importance of machinery redundancy and the physical separation of engine rooms.^8,9 The first post-naval limitation treaty-designed fleet carrier arrived a week after the end of the war. Unconstrained by the Washington Treaty, the Midway-class was able to bridge the technological divide from propeller aircraft to jet-powered naval aviation.

During World War II, the nation lost six aircraft carriers, and it was the only time U.S. aircraft carriers were sunk from hostile action.¹⁰ At the time of its sinking, the Langley was no longer an aircraft carrier but a repurposed seaplane tender ferrying crated fighters for the defense of the Dutch East Indies. Four carriers were sunk in the first year of the war, and the last loss was the light carrier (CVL) Princeton in October 1944 at the Battle of Leyte Gulf. Once wartime industrial production hit its stride by January 1944, the Navy reached its zenith in August 1945 with a fleet of 99 aircraft carriers (28 fleet carriers and 71 escort carriers).¹¹ The bottom line is that World War II experiences validated the importance of carrier designs to ensure the ship could fight despite battle damage.¹² Modern U.S. aircraft carriers continue that legacy in stringent design specifications written in blood. Carriers are usually well protected and operated in concert with escort warships, providing air and submarine defense. 

Adaptation – Cold War

The war in the Pacific set important precedents in carrier design and reaffirmed during the conflicts of the Cold War, namely Vietnam, Korea, and the Gulf War. The Midway-class began its design process in 1940 to lead attacks on Japanese island garrisons and surface action groups. These new aircraft carriers were nearly double the size of the Essex-class at 58,600 tons and a flight deck almost 100 feet longer at 968 feet. Arriving too late to see service in World War II, the Midway-class made its mark in the early Cold War evolution of jet-powered naval aviation. The larger size enabled the carriage of more fuel, defenses, radar, and aircraft. It also allowed modernization in the 1950s to carry the first jet-powered carrier-based naval aircraft, the FH-1 Phantom. The final ten Cold War carriers were of the nuclear-powered Nimitz-class, which remain in service today. The airwing also adapted throughout this period to counter the potent Soviet submarine threat with dedicated anti-submarine warfare aircraft. After the fall of the Soviet Union, the threat was deemed minimal and could be adequately covered by land-based aircraft and shipboard helicopters. The last carrier-based anti-submarine fixed-wing aircraft, the S-3 “Viking,” ended its sea service in 2009.

What will be the carrier strike group’s development focal point for future naval combat?

Two factors weigh on the response to this question: the survivability of the carrier and its airwing under modern threats, principally Chinese, and the effective long-range employment of the airwing beyond effective enemy defenses. Of these, the factor meriting the greatest focus, given the maturity of the current Ford-class design today, is the need for longer-range aircraft and weapons. This will impact the mission-airwing-carrier developmental cycle going forward.

Today, the U.S. Navy struggles to adapt its current F/A-18 attack aircraft and increasing numbers of the F-35 to meet longer-range requirements. One bridging solution is with drones repurposed to function as tanking aircraft like the MQ-25. Of course, the F/A-18 also doubles today as a tanker, but this detracts from available aircraft to execute strike missions. This modus operandi must change and will propel designs of future carrier aircraft with operational ranges exceeding 1,500 miles. New operational requirements will also inform future carrier design, such as the requirement for larger ammo elevators, support systems, and size of the airwing, amongst other considerations. The Electromagnetic Aircraft Launch System (EMALS) is an example of a new system to avoid costly future catapult re-designs that, without, would lead to aircraft or weapon capability sacrifices.¹³ EMALS can adjust the force more precisely and across a larger spectrum used to launch aircraft, using more force for future heavier-loaded aircraft and less for lighter unmanned aircraft.

Effective long-range employment of the airwing will rely on an effective and dispersed sensor network. Much is written on this concept, referred to by the Defense Advanced Research Projects Agency (DARPA) as Mosaic Warfare. This concept would, if achieved, employ a network of sensors and weapon systems that would overwhelm an adversary while providing seamless sensor coverage, like tiles in a mosaic.¹⁴ What is needed to achieve this tessellation is largely known, leaving the resolution of various engineering and operational problems to endeavors such as the Department of Defense’s Joint All-Domain Command & Control (JADC2).¹⁵ What is clear is that target-level data will need to be passed seamlessly amongst various platforms to create the opportunity for the best-placed weapon to be employed against the enemy. The carrier will be a network-making node in this construct, providing platforms and operational control to manned and unmanned platforms. That said, given the distances and enemy interference, dispersed command nodes of the airwing will be needed beyond the carrier.

Longer-range air-to-air missiles will be another key element informing the composition and design of airwings and the aircraft carrier. New missiles may require modifications to existing carrier elevators as longer-range weapons typically are larger and heavier. These long-range weapons may include hypersonic missiles with a larger fuselage and weight, adding demands on the carrier and aircraft design.

Sortie rates still matter, giving rise to the need for what could be called a modern escort carrier. Such ships would allow large, manned carriers to focus on strike missions using heavier payloads. In contrast, largely drone-equipped carriers could provide the strike group’s air defense at a shorter range but with longer sustained operations. Given the threat of massed air, drone, and missile threats, the ability to mass large numbers of airborne aircraft continues to matter and is playing out in the Red Sea under massed Houthi missile and drone attacks.

Era of Tessellation – Carrier Operations in a Modern Pacific War

Taking the above together, the aircraft carrier and its airwing of the future are perhaps best viewed as a link between platform tiles in a sensors-weapons mosaic. The aircraft carrier sustains a robust aerial network of aircraft and assists in coordinating massive targeting data processes for prolonged periods. The carrier will critically retain the ability to execute five or more days of combat operations before leaving station to rest and refit. This aligns with the aircraft carriers’ historical experience, role, and mission. At the same time, U.S. systems’ range and response time are crucial in overwhelming the enemy’s sensors-weapons network. The U.S. system must integrate sensor coverage from carrier airwings, naval warships, shore, and space-based sensors to support long-range weapons. Response time will be critical as a modern adversary like China should be assumed to possess parity with the ability to detect and target U.S. forces. To accelerate decision cycles and targeting, Mosaic Warfare envisions massive data processing using artificial intelligence to synthesize and recommend placement for naval platforms for the best chance of victory.

In such a construct, future carrier operations offer mobility that adds significant complexity to an adversary that fixed targets cannot. Taking the fight to China inside the first island chain requires penetrating deep into China’s anti-access envelope to conduct strikes. Another carrier mission that will see added emphasis is the need to provide a screen for Army and Marine Corps forces operating within the first island chain. Those ground and amphibious forces will provide land-based weapons and sensor coverage to cue naval operations. Air Force and Navy land-based aircraft must be integrated into this tessellated sensors-weapons battlespace. Of course, to remain in the fight, land forces must also be resupplied.

The Marine Corps and the Army plan a maneuver campaign within the first island chain, which is intended to contest China’s naval and air operations. The Marine Corps concepts are expeditionary advanced base operations (EABO) and littoral operations in a contested environment (LOCE).¹⁶ These concepts inform the Marine Corps’ Force Design 2030, envisioning a light, mobile amphibious force. The Army’s concept is similar but less mobile, emphasizing long-range missile systems to include air and missile defenses. The Marines are restructuring their forces to include new formations called littoral regiments.^17,18 These new regiments are purpose-built to provide highly mobile air defenses centered on the new AN/TPS-80 radar system and road-mobile launchers of anti-ship missiles to hold enemy warships at risk just over 100 miles from shore.¹⁹

For the Army, the concept of operations is multi-domain operations (MDO). The Army will likely deploy tailored multi-domain task forces (MDTF) to counter the first island chain’s specific threats.²⁰ The MDTF would likely be equipped with air defenses, radars, and long-range rockets like the Precision Strike Missile, with an approximate 300-mile range.²¹ Also under development is long-range hypersonic weapons (LRHW) modeled on the Navy’s hypersonic weapon development with an estimated range of 1,725 miles.²²

To succeed in the first island chain, the Marines and the Army will need logistics ships and mobility to complicate Chinese targeting. A carrier and airwing designed for air dominance could provide that screen as those ground forces are re-positioned or resupplied. At the same time, ground forces would receive and provide targeting data for threats as the carrier screening force sweeps through the area.

In a modern Pacific war, the aircraft carrier and its airwing must execute a screening force along the first island chain and a surge strike force. Historically, carriers acted as screens, notably during the Battle of the Santa Cruz Islands as Marines fought on Guadalcanal.²³ Also, while evading Japan’s extended maritime defenses, carriers famously executed a series of strikes during the Doolittle Raid. By the end of the war, large fast carrier task forces executed raids on the Japanese home islands and Taiwan. As proven in that war, carriers are remarkably survivable and complicate China’s ability to defend and target U.S. forces.

An attempt was made to achieve operational integration between naval carriers and their airwings with other services called Air-Sea Battle. The concept was born from a collaboration between the Navy and Air Force in 2009 to address the challenge of China’s capabilities by developing and practicing new joint tactics.²⁴ However, it failed to gain traction and funding, and by January 2015, it had been folded into the Joint Staff, effectively sideling the effort.²⁵ In a January 2023 article, Admiral James Foggo and Steven Wills argued for resurrecting the Air-Sea Battle, given developments in long-range weapons advances in networks.²⁶ The time is ripe for a relook. After all, achieving effective operational tessellation of the Western Pacific requires a high degree of integration. The carrier and its airwing will be a critical, mobile platform enabling significant sensors-weapons tessellation of the battlefield. The carrier and its airwing must be seamlessly integrated with land and space-based platforms and sensors to overcome China’s significant sensor and missile threats. This will require technological advances as advocated by the proponents of Mosaic Warfare, but also developing the operational rigor learned through a new series of fleet problems backed by a resurrected Air-Sea Battle initiative.

Conclusion

The good thing is that the technology being proven now on Ford, like the advanced arresting gear and electromagnetic aircraft launch systems, provides the flexibility needed for deploying a wider range of aircraft with future munitions. The key will be how well these systems have performed recently in the Eastern Mediterranean during the ship’s 2023 deployment. This information will inform decisions for future carrier and airwing designs and operations that maximize flexibility and adaptability – a core feature and advantage of the aircraft carrier stretching back to its origin.

Captain Brent Sadler (Ret.) joined the Heritage Foundation as a Senior Research Fellow in 2020 after a 26-year naval career in nuclear submarines and as a foreign area officer. He has extensive operational experience in the Western Pacific, having served at Seventh Fleet, Indo-Pacific Command, as Defense Attache in Malaysia, and as an Olmsted Scholar in Tokyo, Japan.

References

1. “Paris Naval Conference 2024: The Evolving Role of the Carrier Strike Group,” French Institute of International Relations, January 25, 2024 (accessed February 27, 2024).

2. Sam LaGrone, “Navy Refining Plan for its $17B Destroyer Electronic Warfare Backfit with 4 Test Ships,” USNI News, January 19, 2024 (accessed February 27, 2024).

3. E. B. Potter, Sea Power: A Naval History, second edition (Annapolis: U.S. Naval Institute, 1981), pg. 500-501.

4. David Hobbs, British Aircraft Carriers (Yorkshire: Seaforth Publishing, 2013), pg. 119-129.

5. Norman Friedman, U.S. Aircraft Carriers: An Illustrated Design History (Annapolis: Naval Institute Press, 1983), pg. 47.

6. Albert A. Nofi, To Train the Fleet for War: The U.S. Navy Fleet Problems, 1923-1940 (Newport: U.S. Naval War College Press, 2010). Pg. 109-126.

7. “USS Ranger (CV-4),” Naval History and Heritage Command, (accessed March 7, 2024).

8. “Structural Repairs in Forward Areas During World War II,” Bureau of Ships, December 1949, pg. 82-84,  (accessed March 8, 2024).

9. Norman Friedman. U.S. Aircraft Carriers: An Illustrated Design History (Annapolis: Naval Institute Press, 1983), pg. 91 and 154-155.

10. Cid Standifer, “Sunk, Scrapped or Saved: The Fate of America’s Aircraft Carriers,” USNI News, August 18, 2014 (accessed May 1, 2024).

11. Thomas Heinrich, Warship Builders: An Industrial History of U.S. Naval Shipbuilding 1922-1945 (Annapolis: Naval Institute Press, 2020), pg. 91-92, 97-102 and 114-116.

12.  Bureau of Ships, “Structural Repairs in Forward Areas During World War II,” U.S. Navy Department, December 1949, pg. 89-97, (accessed May 2, 2024).

13. “Electromagnetic Aircraft Launch System (EMALS),” Naval Air Systems Command (accessed May 2, 2024).

14. “DARPA Tiles Together a Vision of Mosaic Warfare: Banking on cost-effective complexity to overwhelm adversaries,” Defense Advanced Research Projects Agency (accessed May 1, 2024).

15. “Summary of the Joint All-Domain Command and Control Strategy,” Department of Defense, March 2022 (accessed May 2, 2024).

16.  Andrew Feickert, “U.S. Marine Corps Force Design 2030 Initiative: Background and Issues for Congress,” Congressional Research Service, June 30, 2023, pg. 1,3,7 and 11, (accessed April 27, 2024).

17. “Marine Littoral Regiment,” U.S. Marine Corps, January 11, 2023 (accessed May 2, 2024).

18. “Marines Strike Ship With Pair of Naval Strike Missiles,” U.S. Marine Corps, August 21, 2021 (accessed May 2, 2024).

19. “2^nd Battalion, 11^th Marine Regiment Becomes First Marine Unit to Fire NMESIS Missiles,” U.S. Marine Corps, June 29, 2023 (accessed May 2, 2024).

20. Andrew Feickert, “Defense Primer: Army Multi-Domain Operations (MDO),” Congressional Research Service, January 2, 2024 (accessed April 27, 2024).

21. Andrew Feickert, “U.S. Army Long-Range Precision Fires: Background and Issues for Congress,” Congressional Research Service, March 16, 2021, pg. 16-18, (accessed May 2, 2024).

22. Andrew Feickert, “The U.S. Army’s Long-Range Hypersonic Weapon (LRHW): Dark Eagle,” Congressional Research Service, March 13, 2024 (accessed May 2, 2024).

23. Lars Celander, How Carriers Fought: Carrier Operations in World War II (Philadelphia: Casemate, 2018), pg. 158-171.

24. “Air-Sea Battle,” Air-Sea Battle Office, May 2013, pg. 4, (accessed May 2, 2024).

25. Sam LaGrone, “Pentagon Drops Air Sea Battle Name, Concept Lives On,” USNI News, April 27, 2024 (accessed May 2, 2024).

26. James Foggo and Steven Wills, “Back to the Future: Resurrecting ‘Air/Sea Battle’ in the Pacific,” Breaking Defense, January 24, 2023 (accessed May 2, 2024).

Featured Image: Eugene Ely flies his Curtiss pusher biplane from the USS Birmingham in Hampton Roads, Virginia, on Nov. 14, 1910, the first time an airplane took off from a U.S. warship. (Photo via Wikimedia Commons)

By Andrew Song

How does one find an object not meant to be found? Forensic maritime investigators in 2017 stumbled across this question when searching for the disappeared ARA San Juan (S-42) – an Argentinian submarine whose mission centered around stealth. Despite the environmental challenges and the restrictions imposed by the profile of submarines, several complementary forensic tools have emerged as authoritative standards and best practices for underwater search operations. These include: (1) optimization of preliminary search boxes through Bayesian probabilities, with updates for posterior probabilities throughout the search; (2) side-scanning sonar systems; and (3) unmanned underwater vehicles (UUVs) for imagery, access, and identity verification. In explaining the efficacies and drawbacks of such methods, this analysis highlights the importance and evolving future of search optimization strategies.

How to Find a Lost Submarine

Forensic maritime investigators confront distinct challenges not relevant for traditional land-based investigations. Unlike terrestrial-based forensics, pre-established knowledge of a local maritime environment is sparse. Scientists have mapped 1/5th of the sea floor to modern standards with 100m resolution, but that means almost 290 million square kilometers of seafloor—twice the surface area of Mars—have not yet been surveyed.¹ Furthermore, the remoteness of submarine operational areas casts a wide speculative net for a submarine’s last location, acting as a red herring for planners. For instance, the French Navy finally found the Minerve in July 2019 after searching since 1968, but the submarine’s position was only 28 miles off the coast of Toulouse.²

The absence of existing charts, therefore, necessitates simultaneous 4-D mapping of the area—which is in short supply. Submarine debris is unidentifiable in satellite and aerial images due to surface opacity and the extreme depth of wreckages. Stratification conceals wreckage and clearing sedimentary buildup becomes extremely complicated due to sheer volume. An onsite “walk-over” survey, as described by Fenning and Donnelly³ in their description of geophysical methodologies, is simply impossible in a marine environment. Acidity and pH levels of the water also influence rates of decomposition, and must be considered for a simulation in the casualty scenario.

1: Bayesian Search Strategies

Constructing a preliminary search box requires meticulous strategizing and calculations. An error associated with misanalysis of primary sources can inevitably mislead search and rescue planners, delaying a submarine’s discovery. This occurred in the case of the USS Grayback, as Navy officials mistranslated the final coordinates of the submarine documented by a Japanese carrier-based bomber.⁴ An incorrectly interpreted digit in the longitudinal coordinates created an erroneous search area straying 160 kilometers from the Grayback’s actual location.⁵

Pitfalls in relying on a single source cause planners to use search strategies based on Bayesian statistics. At a rudimentary level, Bayes’ theorem leverages probabilities of an event and prior knowledge regarding the condition of such event to produce a reasonable prediction of an event’s occurrence. Stakeholders will first formulate a range of possible stories surrounding a missing submarine’s location, pulling from all potential sources (eyewitness testimony of submarine’s last submergence, operational logs, mission record, etc.). The credibility and value of each piece of evidence will be judged by investigators and experts who will then collectively assign statistical weight to possible scenarios. For instance, the USS Scorpion’s forensic team invited experienced submarine commanders to present reasonable hypotheses that the scientists would later input into a probability density function.⁶ Such probability density functions assist planners in prioritizing certain search zones for surveying. Investigators resort to Bayesian statistics and Bayesian inference models because of its predictive power and the comprehensive results derived from relatively few inputs. Figure A demonstrates a four-step hierarchical convention in a Bayesian search strategy. The diagram summarizes the effects of updates on the model and introduces the posterior probability function (PPF).

When a search area fails to yield any evidence pointing to a submarine, a posterior probability function will be calculated. A PPF’s utility and role is best explained by Equation (1-2)’s hypothetical representation of a grid square’s probability of containing a submarine. Variable q represents the probability of successful detection of a wreck and p quantifies the probability that the grid square does contain the wreck. Failing to find a wreck in a grid square will revise the probability of that grid square into p prime—a posterior probability.⁷ In this theoretical situation, the probabilities (for purely illustrative purposes) are: that a wreck in the grid square is 67% and the chances of a side-scan sonar identifying an anomaly is 85%.

Under those numeric assumptions, if the submarine were not found in the first survey, then a second survey of the same grid square, as denoted in Equation (3), will yield a secondary posterior probability of approximately 4.2%. Taken together, 4.2% represents the chances of success in finding the submarine in the given grid square in a second sweep.

Bayesian strategies are a staple of operations analysis search theory. For instance, the U.S Coast Guard incorporates Bayesian search strategies into its Search and Rescue Optimal Planning System (SAROPS).⁸ Successful outcomes produced by Bayesian search strategies have led to a general consensus on the technique’s utility. Identification of the underwater wreckage site of Air France Flight AF 477 underscored this utility. In the 2011 discovery, investigators created probability density functions (PDFs) from weighted scenarios supplemented by anterior knowledge of nine commercial aircraft accidents, known flight dynamics, and final trajectories.⁹ These PDFs drew search boxes that broadened until a Brazilian corvette recovered components of AF 477 buoyed on the surface.

However, Bayesian search strategies warrant legitimate criticism for their implicit use of subjective analysis. Terrill and Project Discover’s usage of Bayesian search strategies narrates a story of arbitrary values associated with each scenario. This is seen especially when the researchers place heavy subjective weight on interview data from the few remaining witnesses of a B-24 bomber’s last location.¹⁰ Taken together, Bayesian search strategies force analysts to quantify what is essentially qualitative information (e.g., the probability that an elderly man can accurately recall the events of the crash). These limitations create possibilities for higher uncertainty and a wider confidence interval. In addition, Bayesian search strategy can overshadow other powerful methods to form search boxes such as a Gittins index formula.¹¹

2: Implementation of Side-Scanning Sonar for Seabed Imaging

Sonar, otherwise known as sound navigation and ranging, is a method that leverages sound propagation as a way to detect an object’s position and to visualize shapes from acoustic signatures in the form of echoes. The return frequency and radiated noise of an object allow for target acquisition and safe navigation by submarines dependent on the vicinity’s sound velocity profile; for researchers hoping to find inactive submarines, side-scan sonars lend mapping capabilities.

These devices construct images from cross-track slices supplied by continuous conical acoustic beams that reflect from the seafloor—wave emission speed can reach nearly 512 discrete sonar beams at a rate of 40 times a second.¹² Data produced by side-scan sonars assembles a sonogram that converts into a digital form for visualization. The utility of side scan sonars is trinitarian; they create effective working images of swaths of sea floor when used in conjunction with bathymetric soundings and sub-bottom profiler data.¹³ Form factors of side-scan sonars allow the device to be highly mobile and serve as flexible, towable attachments for the tail of any-sized ships, giving liberty to human operators to adjust the directionality of ensonification. In addition, side-scan sonars contain adjustable frequency settings. A change in a side-scan sonar’s frequency will affect the sonar’s emitting wavelength, giving the operator flexibility on target acquisition. Side-scan sonars can operate as low as the 50kHz range to cover maximum seabed area; alternatively, the instrument can operate at 1 MHz for maximum resolution. This feature is extremely vital because submarines alter in length by model and different bodies of water share unique sound velocity profiles. Another advantage with side-scan sonars is their high precision record at sub-meter accuracy level for horizontal planes and at the centimeter-error level for vertical planes.¹⁴

Side-scan sonar systems exist as a vital apparatus to any search operation because the alternatives for mapping are minimal. Methods other than side-scan sonars like low-frequency multi-beam bathymetric data scanners, when reappropriated, are imperfect in object identification accuracy and better for scanning large seabed topographic structures like underwater mountains.¹⁵ Recent advances in magnetic anomaly detectors¹⁶ appear promising for future seabed exploration, but these instruments still require parallel approaches or in-tandem usage with side-scan sonars. Until magnetometers can extend their range beyond identifying magnetic objects in the Epipelagic Zone—the uppermost layer of the ocean where sunlight is still available for photosynthesis—side-scan sonars will be more consistent and versatile than magnetometers.

Deployment of side-scan sonar occurs in the intermediary stage of search operations. A vessel will have a side-scan sonar mounted on or embedded in a towfish. Tethered to the main vessel, the side-scan sonar will perform a proper sonar survey of a proposed area by maintaining a rigid survey line along with a consistent towfish “altitude” when trailing the ship. Technicians carefully check the GPS receiver of the towfish to rectify course deviations, if needed, by manually changing the ship and towfish’s heading. A side-scan sonar operates with a survey mode to capture anomalies, which visual graphs will register and mark for later investigation by an unmanned underwater vehicle (UUV).

Unfortunately, handlers of side-scan sonars will notice several limitations that must be accommodated. A restriction to side-scan sonars is their inability to image directly below side-scan transducers. In other words, ships must compensate for a side-scanner’s blind spot by staggering their mow-the-lawn strategy. In addition, side-scan sonars contain software that prohibits the surpassing of a certain speed limit for towing, lest the receiver show significant scattering, absorption, and incoherent imagery. Like other instruments, side-scan sonars’ physical power consumption can be a variable for constraint.

Lastly, side-scan sonars perform according to the quality of the bathymetric data supplied. By themselves, side-scan sonars cannot efficiently identify changes in gradients and sound velocity profiles in real-time. High frequency/high resolution sonars operate at relatively short ranges via direct path sound propagation, which limits the refraction of sound waves and consequent distortion. This means the side-scan sonar will have a handicap in reporting the propagation paths of its rays and the sound channels, meaning knowledge of shadow zones may be omitted.¹⁷ This is a search investigator’s worst nightmare because failure to adequately search a grid may lead to incorrect, permanent marking of a square not holding a target. Imperfect data or simply lack of bathymetry data also contribute to the limitation of side-scan sonars.

3: Integration of Adaptive Unmanned Underwater Vehicles for Forensic Searches.

Since their introduction in the 1960s, UUVs have played a major role in every forensic investigation for a lost submarine. UUVs act as surrogates to human divers who cannot comfortably operate for extended periods of time at depths greater than 100 meters. To illustrate the need for UUVs, the USS Grayback was discovered at a depth of 1,417 feet (431 meters)¹⁸ — an impossible depth for divers, but not for the submarine itself. UUVs support forensic scientists in more than just underwater photography. UUVs collect bathymetry data, use ultrasonic imaging, measure strength of ocean currents, and detect foreign objects by their inertial or magnetic properties. Variants of UUVs are categorized into two robotic classes: remotely operated underwater vehicles (ROVs) and autonomous underwater vehicles (AUVs). ROVs allow for direct piloting by a human operator from a remote location with signal. AUVs function independently and follow pre-programmed behavioral search patterns.

The UUV variant, Remus 100,¹⁹ manufactured by Woods Hole Oceanographic Institute, deceptively resembles a torpedo, but functions as an effective explosive ordnance disposal detection device for the Navy. When refitted for search operations, the Remus (AUV) variant can perform dual-frequency side-scan sonar operations in independent mow-the-lawn search sequences.²⁰ The Remus’ transponder wields GPS and doppler velocity logs that have proven to be more accurate in measurements than earlier AUVs. Customarily, forensic actors will deploy ROVs and AUVs for close-up identification or routine investigation of an anomaly, instead of wide-area search missions. These ROVs display high-definition, colorized video feeds for operators on a vessel; the latency between pilots and the ROV ranges from one to two seconds, making for fast time on responsive decisions.

Conclusion

This analysis examines a trinity of contemporary methods revolving around statistics and autonomous vehicles that aid officials in search and rescue operations for submarines. Corporations and officials should note that innovating and constructing more effective models in search operation becomes worthwhile when speed determines the ability to save lives. While this analysis discusses the employment of the aforementioned technology in the context of submarines, these methods can be theoretically implemented for other maritime interests: finding missing planes, undertaking the historical preservation of shipwreck sites, and embarking on deep-sea mining. For all these reasons, the U.S. has an inherent stake in advancing a discussion about progress in submarine search and rescue tactics.

Andrew Song is a U.S. Navy Nuclear Submarine Officer. His previous publications have appeared in The Wall Street Journal, The National Interest, Military Review, Journal of Indo-Pacific Affairs, and Proceedings. He graduated with a B.A. in Global Affairs from Yale University in 2022.

References

¹ Amos, Jonathan. “One-Fifth of Earth’s Ocean Floor Is Now Mapped.” BBC News. BBC, June 20, 2020. https://www.bbc.com/news/science-environment-53119686.

² “DOS Involved in the Finding of the French Submarine La Minerve.” Deep Ocean Search, October 3, 2019. http://www.deepoceansearch.com/2019/10/03/dos-involved-in-the-finding-of-the-french-submarine-la-minerve/.

³ Fenning, P. J., Donnelly, L. J., 2004. Geophysical techniques for forensic investigation. Geological Society of London Special Publications, 232, 11-20.

⁴ Elfrink, Tim. “A WWII Submarine Went Missing for 75 Years. High-Tech Undersea Drones Solved the Mystery.” The Washington Post. WP Company, November 11, 2019. https://www.washingtonpost.com/nation/2019/11/11/uss-grayback-discovered-tim-taylor-lost-project/.

⁵ Ibid.

⁶ L.D. Stone, “Operations Analysis during the Underwater Search for Scorpion” Naval Research Logistics Quarterly, vol. 18(2), pp. 141–157. 1971

⁷ Terrill, E., Moline, M., Scannon, P., Gallimore, E., Shramek, T., Nager, A., Anderson, M. (2017). Project Recover: Extending the Applications of Unmanned Platforms and Autonomy to Support Underwater MIA Searches. Oceanography, 30(2), 150-159. Retrieved March 1, 2021, from http://www.jstor.org/stable/26201864

⁸ Stone, L. (2011). Operations Research Helps Locate the Underwater Wreckage of Air France Flight AF 447. Phalanx, 44(4), 21-27. Retrieved March 2, 2021, http://www.jstor.org/stable/24910970

⁹ Soza & Company, Ltd. (1996). The Theory of Search: A Simplified Explanation: U.S. Coast Guard. Contract Number: DTCG23-95-D-HMS026. Retrieved on 2010-07-18 from http://cgauxsurfaceops.us/documents/TheTheoryofSearch.pdf

¹⁰ Terrill, E. “Project Recover.” Oceanography 2017.

¹¹ Weitzman, Martin L. (1979). “Optimal Search for the Best Alternative”. Econometrica. 47 (3): 641–654.

¹² “Side Scan Sonar.” Exploration Tools: Side Scan Sonar: NOAA Office of Ocean Exploration and Research, 2002. https://oceanexplorer.noaa.gov/technology/sonar/side-scan.html.

¹³ Jean M. Audibert, Jun Huang. Chapter 16 Geophysical and Geotechnical Design, Handbook of Offshore Engineering, Elsevier, 2005. ISBN 9780080443812, https://doi.org/10.1016/B978-0-08-044381-2.50023-0.

¹⁴ Aaron Micallef. Chapter 13: Marine Geomorphology: Geomorphological Mapping and the Study of Submarine Landslides, Development in Earth Surface Processes, Elsevier, Vol 15, 2011, pg 377-395 ISBN 9780444534460, https://doi.org/10.1016/B978-0-444-53446-0.00013-6 (https://www.sciencedirect.com/science/article/pii/B9780444534460000136)

¹⁵ Elfrink, “A WWII Submarine went Missing” The Washington Post. 2019.

¹⁶ Geophysical Surveying Using Magnetics Methods, January 16, 2004, University of Calgary https://web.archive.org/web/20050310171755/http://www.geo.ucalgary.ca/~wu/Goph547/CSM_MagNotes.pdf

¹⁷ “Side Scan Sonar.” United States Naval Academy , February 1, 2018. https://www.usna.edu/Users/oceano/pguth/md_help/geology_course/side_scan_sonar.htm. (2) Sonar Propagation. Department of Defense . Accessed April 7, 2021. https://fas.org/man/dod-101/navy/docs/es310/SNR_PROP/snr_prop.htm.

¹⁸ Elfrink, “A WWII Submarine went Missing” The Washington Post. 2019.

¹⁹ REMUS”. Woods Hole Oceanographic Institution. https://www.whoi.edu/what-we-do/explore/underwater-vehicles/auvs/remus/

²⁰ J. Ousingsawat and M. G. Earl, “Modified Lawn-Mower Search Pattern for Areas Comprised of Weighted Regions,” 2007 American Control Conference, New York, NY, USA, 2007, pp. 918-923, doi: 10.1109/ACC.2007.4282850.

Featured Image: August 1986 – A view of the detached sail of the nuclear-powered attack submarine USS Scorpion (SSN-589) laying on the ocean floor. The starboard fairwater plane is visible protruding from the sail. Masts are visible extending from the top of the sail (located at the lower portion of the photograph). A large segment of the after section of the sail, including the deck access hatch, is missing. (Official U.S. Navy photograph)