Defense Media Network

What the Semi-submersibles Mean

Transnational Gangs, Drugs, and Terrorism

Since the days of the United States’ Revolutionary War and Connecticut patriot David Bushnell’s Turtle, the idea of a vessel operating just under the surface of the water to launch an attack has been a concern of military, national security, and maritime industry stakeholders. Submerged or semi-submerged craft are incredibly hard to detect, track, and interdict. Therefore, it was only a matter of time before smugglers and terrorists began using these craft for their illegal purposes. Over the past couple of years maritime security forces have confronted the increasing use of self-propelled semi-submersibles (SPSSs) to smuggle drugs into the United States. If SPSSs prove an effective means for transporting drugs into the country, there should be little doubt that terrorists will begin using them to smuggle operatives and weapons, including possibly weapons of mass destruction, into the country. SPSSs represent a serious threat to the security of the United States that must be countered quickly.

As demonstrated centuries ago, an SPSS does not have to be sophisticated. Bushnell, working with his brother Ezra Bushnell, used hand-cranked propellers and quick-release lead ballast for buoyancy. The first attack with this weapon occurred on Sept. 7, 1776, when Turtle’s operator, Sgt. Ezra Lee, attacked HMS Eagle, the British flagship, as it lay at anchor in New York Harbor. The attack failed due to several factors, but the concept remained valid and was improved upon as warfare matured. Today, submersibles range from sophisticated machines of war operated by nation-states to oceanographic research vessels operated by private foundations to tour vessels used by private companies and now criminal organizations. The technology and capability for designing, building, and operating submersibles and semi-submersibles is readily available to all.

Today, as the effectiveness of law enforcement in interdicting surface vessels improves, rumors of drug-trafficking organizations turning to submersibles to counter law enforcement arise frequently, creating a clear concern for both law enforcement and the military. Whether criminal organizations have submersibles or not, there is no doubt that they have and are using SPSSs, as seizures at sea and on shore are increasing. As the former commander of Joint Interagency Task Force South, Coast Guard Rear Adm. Joseph L. Nimmich noted, “Every time we turn around, the smugglers remind us they are extraordinarily creative, extraordinarily adaptive.” There is no doubt that the enemy is adaptive; therefore security forces must be just as creative, agile, and adaptive.

To counter the SPSS threat requires an understanding of that threat. One of the best definitions describing SPSS-like vessels is found on the U.S. Southern Command Web site, which notes:

Self-Propelled Semi-Submersibles (SPSS) represent the emerging sophistication and innovation of drug traffickers to adapt to U.S. and regional counter-drug capabilities. The vessels are designed and built by narco-terrorists in Colombia to smuggle large volumes of cocaine over long distances in a manner that is difficult to detect. Since the vessels have a low profile – the hulls only rise about a foot above the waterline – they are hard to see from a distance, leave little wake and produce a small radar signature. U.S. counter-drug officials estimate that SPSS are responsible for 32% of all cocaine movement in the transit zone. U.S. Southern Command, the U.S. Coast Guard and regional officials consider SPSS a serious threat to U.S. and regional security … [they are] 40-80 feet in length with a freeboard (exposed area above the waterline) of approximately 18 inches, a crew of 4 persons, and able to carry 4 to 12 metric tons of cocaine … We assess the use of SPSS vessels has grown in recent years as a means to counter effective U.S. drug interdiction efforts. Since 2006, there have been multiple known SPSS events. Drug traffickers continue to adapt to law enforcement successes. The SPSS, once perceived as an impractical and risky smuggling tool, has proven successful as an innovative and highly mobile, asymmetrical method of conveyance.

SPSSs are exceptionally difficult to detect and track due to their low radar profile and nearly undetectable deep water (dark blue) paint scheme. Built in relative secrecy and “unregistered” or “undocumented” status makes it relatively impossible to accurately assess how many such vessels are in production or operating. The U.S. Coast Guard San Diego Public Affairs Detachment noted in a March 25, 2009 release:

They are often referred to by some as “Sasquatch of the Pacific.” They are rarely seen and almost never apprehended, and have emerged as the prevailing smuggling threat in the vast ocean waters of the Eastern Pacific. To make apprehension even more difficult, the crews piloting the SPSS have consistently scuttled or intentionally flooded their vessel, sending the craft and its multi-ton load of cocaine to the bottom of the ocean. Through the activation of one or more scuttling valves, the SPSS operators can sink their vessel in minutes. Upon being detected and after seeing Coast Guard or Navy ships move in for the intercept, the SPSS crews often climb on top of the SPSS, don lifejackets, and literally let the vessel sink beneath them. The smugglers’ intentional sinking turns into a fabricated search and rescue case as the smugglers are in the water, now victims of the sea.

The difficulty of capture has been recognized internationally. As the June 16, 2008, online edition of the internationally respected Jane’s Defence Weekly ( noted:

A terrorist submarine attack might seem like a James Bond scenario, but drug smugglers linked to the Revolutionary Armed Forces of Colombia (Fuerzas Armadas Revolucionarias de Colombia: FARC) are already using semi-submersible vessels to transport multi-tonne cargoes of cocaine. Up to 40 such vessels left South American shores in 2007 and more are expected in 2008 … Captain Robert Watts, a United States Coast Guard officer who has tracked maritime drug smuggling trends, told Jane’s that the first experimental SPSS was found in Colombia in 1989. However, such vessels did not become practical until global position system (GPS) technology became widely available and the US and Colombian authorities began to effectively counter the ‘go-fast’ speedboats typically used by the smugglers, according to Capt Watts. The growing numbers of SPSS vessels indicates that their stealthy characteristics and ability to carry many tonnes of cocaine have helped them develop into what now seems to be a major component of the narcotics logistics chain. The Colombian Navy believes that during the past two to three years, cocaine smuggling SPSS vessels have been arranged mostly by the drug trafficking factions of the FARC, probably in association with organized crime groups also involved in drug trafficking.

U.S. Coast Guard and Navy law enforcement seized 37 bales of cocaine from a self-propelled semi-submersible craft Sept. 13, 2008. The Coast Guard LEDET was embarked aboard the USS McInerney and a Navy maritime patrol aircraft spotted the SPSS and vectored the McInerney to the location of the smuggling vessel. Four suspected smugglers were taken into custody. U.S. Navy photo by Petty Officer 1st Class Nico Figueroa.

While the use of SPSSs so far appears to have been limited to drug smuggling, their potential as a means for conveying terrorists and/or their weapon systems is clear. This concern was best stated by one of the most visible Department of Defense combatant commanders. Writing in the U.S. Naval Academy Alumni Association’s Shipmate magazine, the then-commander of U.S. Southern Command, Adm. James Stavridis, noted:

Gangs and smugglers use their enormous profits to secure and preserve positions of power by whatever means necessary, resulting in mass homicides, corruption, and subversion of rule of law. We also know that drug traffickers use illegal drug money to assist rogue states and international terrorist organizations that are determined to build and use weapons of mass destruction, such as the FARC narco-terrorists in Colombia. In this sense, growing global demand for drugs such as cocaine, heroin, and marijuana directly links the world drug trade to international terrorism … Semi-submersible, low-profile vessels transport drugs for profit, and they do so effectively. It does not take a great leap to imagine what danger awaits us if drug traffickers choose to link trafficking routes and methods with another – perhaps even more profitable – payload. In simple terms, if drug cartels can ship up to ten tons of cocaine in a semi-submersible, they can clearly ship or “rent space” to a terrorist organization for a weapon of mass destruction or a high-profile terrorist … In ever-increasing numbers, these stealthy, pod-like vessels depart expeditionary shipyards nested deep in the dense jungles and estuaries of the Andes region of Latin America. Carefully ballasted and well camouflaged, they ride so low in the water that they are nearly impossible to detect visually or by radar at any range greater than 3,000 yards. Loaded to capacity with tons of drugs they plod steadily and generally unobserved at less than ten knots toward designated drop-off points, depositing their payloads of sorrow and death – translating into thousands of deaths in the USA – for further transit to global consumer markets.

Despite their stealth-like characteristics, there have been successful interdictions of SPSSs over the past few years. In August 2007, the Australian Broadcasting Company (ABC) reported on a joint interdiction of an SPSS off of Central America with $352 million worth of cocaine. The article continued:

U.S. Customs and Border Protection said the semi-submersible vessel – which was only partially visible from the surface – was spotted by a surveillance plane 482 kilometers south-west of the Mexico-Guatemala border on Monday. The plane then guided a U.S. Navy ship to the scene as the four suspected drug smugglers scuttled the vessel, along with the bulk of its cargo, believed to be around 5,000 kilograms of cocaine. The suspects and 11 bales of cocaine weighing around 548 kilograms were eventually recovered from the scene.

On Sept. 17, 2008, the U.S. Coast Guard Cutter Midgett, a 40-year-old Coast Guard high-endurance cutter, interdicted a 60-foot stateless SPSS vessel carrying over 14,000 pounds (approximately 7 metric tons) of cocaine valued at over $196 million approximately 400 nautical miles south of the Mexico/Guatemala border. This was a joint interdiction with the U.S. Navy.

This interdiction followed a nationally covered nighttime boarding and seizure of another SPSS on Sept. 12-13, in which a Coast Guard boarding team surprised the SPSS captain and crew with a no-notice boarding. Despite the best efforts of the SPSS’s crew to drown the boarding team by scuttling, they eventually complied with orders to disengage the scuttling devices on the vessel. The boarding team discovered 7 metric tons of cocaine and the four-man crew faces prosecution in the United States.

The U.S. Coast Guard seized this self-propelled semi-submersible (SPSS) vessel carrying 7 tons of cocaine on Sept. 12, 2009.

Another successful interdiction occurred in January 2009, when the USCGC Chase, another aging high-endurance cutter, with an embarked helicopter from Coast Guard Air Station Port Angeles, Wash., stopped a 50-foot SPSS. Initially the smugglers had thought that they had successfully scuttled the vessel. Their attempt failed and the Coast Guard boarding team got aboard. After what seemed like an extensive period of time, the boarding team reported “touchdown” … finding 199 50-pound bales and 2,293 kilogram-weight “bricks” of cocaine. The interdicted vessel was later dubbed “Big Foot.”

According to an April 28, 2009 article in The Tampa Tribune, “Crews from about a dozen semisubs have been prosecuted in federal court in Tampa as part of Operation Panama Express, a long-term Tampa investigation into Colombian maritime drug smuggling.”

As the effort continues to thwart these vessels, U.S. law enforcement agencies now have a new law to support their efforts. On Jan. 3, 2008, Public Law 110-407, The Drug Trafficking Vessel Interdiction Act of 2008, was signed into law. Sponsored by current Vice President Joe Biden, then a U.S. senator, the law specifically targeted SPSS vessels by stating:

“Congress finds and declares that operating or embarking in a submersible vessel or semi-submersible vessel without nationality and on an international voyage is a serious international problem, facilitates transnational crime, including drug trafficking, and terrorism, and presents a specific threat to the safety of maritime navigation and the security of the United States.”

The law goes on to clarify the offense:

“Whoever knowingly operates, or attempts or conspires to operate, by any means, or embarks in any submersible vessel or semi-submersible vessel that is without nationality and that is navigating or has navigated into, through, or from waters beyond the outer limit of the territorial sea of a single country or a lateral limit of that country’s territorial sea with an adjacent country, with the intent to evade detection, shall be fined under this title, imprisoned not more than 15 years, or both.”

While dramatic at-sea interdictions have garnered much press, perhaps the best counter strategy is destroying the SPSSs during construction. The U.S. government has been working with many South American countries from which these vessels originate to locate and destroy them before they are launched. For example, Colombia passed a law criminalizing the financing, construction, storage, transport, or use of semi-submersibles or submersibles with illicit intent. Such parliamentary action as this, coupled with aggressive action by law enforcement, offers a significant counter to a serious threat.

The issue will continue to be an ongoing effort of adaption. In an article written by Gordon Lubold from The Christian Science Monitor, dated Aug. 25, 2008, the writer quoted the current U.S. Northern Command Commander, Air Force Gen. Victor “Gene” Renuart, during the general’s interview on C-SPAN’s Newsmakers: “These narcotics traffickers, much like terrorists in other parts of the world, are learning adversaries … As you close one loop, they will open another … If we believe we have solved the problem, we are almost guaranteeing it will come back. You can’t take your eye off the ball in this kind of solution.”

SPSSs offer a significant threat to the security of the nation’s maritime borders. If smugglers realize significant success employing these insidious craft, there can be little doubt that terrorists will follow suit. Therefore law enforcement agencies, supported by the military and in partnership with other nations, must act aggressively to counter the threat. However, in the forthcoming period of austere if not declining agency budgets, the ability to act aggressively will be severely challenged, putting the outcome in doubt.

This article was first published in The Year in Homeland Security: 2009 Edition.

    li class="comment even thread-even depth-1" id="comment-365">

    It’s a sad essay on our times when all this technological ingenuity goes toward something so foul as cocaine smuggling. I hope the USCG or the navy is able to reverse-engineer these vessels and perhaps get some fresh ideas they can use to defeat these criminals.

    li class="comment odd alt thread-odd thread-alt depth-1" id="comment-367">

    …or it shows how desperate that these criminals and terrorists have become. The need to utilize these “new” semi-subs indicates that the efforts of law enforcement and our defense personnel are having an impact.

    li class="comment byuser comment-author-chuck-oldham even thread-even depth-1" id="comment-368">
    Chuck Oldham (Editor)

    The worrisome things for me are the economics and the other potential uses.

    The smugglers are perfectly happy to scuttle a boat that cost up to an estimated $2 million to build and crew, and a cargo worth several hundred million dollars, as the price of doing business. You tell me: what’s an acceptable percentage of “business losses”? Because if they can absorb a dozen SPSSs being lost or captured, how many more must be getting through to make the strategy viable?

    Second, I’m with Adm. Stavridis that if they can transport up to 12 tons of cocaine, they can transport 12 tons of any other extremely dangerous payload.

    And now the smugglers are working on true submarines rather than what are essentially boats with extremely low freeboards.