Submersibles Evolution: From Deep-Sea Exploration to Science and Tourism

As outlined in the submarine entry, submersibles differ in size in terms of construction, movability, and range. Submarines are larger crafts designed with substantial crews to pursue mostly long-range military goals. Submersibles are designed to be much smaller with minimal staff and to resist extreme water pressure at much greater depths than submarines while pursuing primarily scientific objectives. However, during the second half of the twentieth century, the clear-cut difference between the two became much more blurred as modern submersibles seemingly resembled small submarines.

The original designs to submerge below the waves resembled submersibles rather than submarines. However, the development of fossil fuel engines and turbines made the development of submarines possible. It helped secure these vessels a prominent role in the twentieth century’s global hot and cold wars. The first true bathyspheres (gk. for deep sphere) developed in the late 1920s and early 1930s. Their design allowed them to break the limiting barrier of about 500 feet (150 meters) that could be reached by submarines and divers wearing armored suits. The bathysphere ultimately quadrupled this maritime depth and uncovered a whole array of aquatic life forms to an expectant public listening to the radio and reading newspaper articles. Still, bathyspheres did not operate under their own power and were usually lowered and controlled from a ship or platform.

As the Second World War ended, national navies became increasingly interested in this research and invested in more mobile crafts. In the 1950s, the French Navy sponsored a design by the Swiss inventor Auguste Piccard, the Trieste, a self-propelled bathyscaphe (gk. for deep vessel). The US Navy later purchased this submersible, and in 1960, it managed to reach the bottom of the Challenger Deep in the Mariana Trench, the deepest known point in the seabed at almost 11,000 meters (or close to 36,000 feet). Realizing the potential of submersibles, the US Office of Naval Research started to finance oceanography and the exploration of the oceans’ deep. While this investment secured the uncovering of underwater geology, such as deep-water vents, it also served to monitor the movement of Soviet submarines during the Cold War and locate missing US submarines, such as the USS Thresher, that failed to surface in 1963. This collaboration between naval and scientific institutions resulted in Alvin, named after its prime developer, Allyn Vine, in 1963. The submersible rotated between scientific—locating geological features on the bottom of the ocean—and military—raising an unarmed hydrogen bomb off the Mediterranean coast of Spain in 1966—aims. The expansion of submersibles ironically coincided with the space race and indicated an accelerated pace of technology. For the submersible, it introduced a titanium sphere to withstand the pressures of the ocean deep, allowing for a small crew, initially no more than two to three individuals, to perform exploration in a formerly restricted realm. Portholes afforded visual access to the ocean floor, while mechanical arms attached to the submersible allowed for the collection of samples. Perhaps the most significant discovery in the 1970s was the encounter of hydrothermal vents that would fuel new fields of scientific research. Developments in robotics by the 1990s allowed for an increasing deployment of remote operating underwater vehicles. However, especially in scientific exploration, the staffed submersible proved advantageous. Although instruments significantly improved in the late twentieth century, the ability to place a human being at the point of observation and to make sound decisions as to where to put the vessel and what samples to collect greatly surpassed robotic dives.

Over the next few decades, Alvin’s potential alerted other organizations to invest in these deep-sea vessels. Economic interests include deep-sea water mining and oil and gas drilling. Many companies in such ventures operate unmanned robotic submersibles, allowing people to explore increasingly valuable resources at greater depths. This also meant that submersibles moved beyond their narrow confines of military and scientific aims to target wealthy tourists who would be able to tour out-of-the-way shipwrecks such as the Titanic. Since the 2020s, submersibles have become the final frontier of expensive superyachts that, in addition to helipads, would carry underwater crafts to explore what lies underneath the ship.

The slow but steady expansion of submersible tourism also harbors risks, as the Titan submersible implosion in June of 2023 illustrates. OceanGate operated the submersible, one of only five to reach an ocean depth exceeding 4,000 feet, to shuttle tourists to the legendary shipwreck of the Titanic for the astronomical fee of $250,000. Operating in international waters, the Titan was not subjected to any regulations, and OceanGate forwent third-party certification for the submersible. Although concerns were raised since the beginning of the commercial dives, Titan operated for several years until June 18, 2023, when its hull imploded, instantly killing the five people aboard the submersible. The tragedy led to a call for closer regulation of deep-sea submersibles.

Unfortunately, another offshoot of such submersible technology is the employment of such vessels in more illicit activity. Narcotraffickers seek to explore more creative ways to smuggle drugs into countries where the street value of products remains high. Although the price of submersibles prevents their widespread use, the potential to evade Coast Guard vessels and explore legal loopholes makes these crafts an ideal alternative to conventional ways of smuggling drugs across national boundaries.

FURTHER READINGS: Geyer, R. A. 1977. “Submersibles and Their Use in Oceanography and Ocean Engineering.” Ocean Management 3 (2): 137-44.

Madsen, Brad. 2006. Decent: The Heroic Discovery of the Abyss. New York: Vintage Books.

Taub, Ben. 2023. “The Titan Submersible Was ‘An Accident Waiting to Happen.” The New Yorker. https://www.newyorker.com/news/a-reporter-at-large/the-titan-submersible-was-an-accident -waiting-to-happen. Accessed March 16, 2024.

Wilson, Brian. 2011. “Submersibles and Transnational Criminal Organizations.” Ocean and Coastal Law Journal 17: 1-30.