The Hunt for Narco Subs
Photo: US Coast Guard


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The Hunt for Narco Subs

If Colombian narco sub busts are so rare, how many drug-loaded semi-submersibles go by undetected?

The vessel cut a low profile as it slipped through international waters, hundreds of miles off the coast of El Salvador in the eastern Pacific Ocean. It was mostly submerged, except for an exhaust pipe and a windowed cockpit that poked a few feet above water. Painted a dull blue-green, the 40-foot semi-submersible pressed on with a silent intent that belied its load: a diesel engine, fuel tanks, navigation equipment, four crew members, and 14,000 pounds of cocaine.


Captain Nathan Moore, commanding officer of US Coast Guard cutter Stratton, could not yet see this mystery vessel from where he stood aboard Stratton, roughly 200 miles south of Puerto Escondido, Mexico, around lunchtime on July 18. He told me the weather and sea conditions were typical of that time of year in the eastern Pacific—hazy, 95 degrees, four to six foot waves, and a light 12-knot wind. But it wasn't an ordinary day. Moore had reason to believe what he was looking for was the sort of stealthy, bespoke watercraft designed and used primarily by Colombian drug traffickers to move cocaine through the Pacific maritime smuggling corridor to Mexico, where the drugs are offloaded and funneled north into the US, sometimes en route to Europe.

Moore's radio crackled.

"Stratton, we have a visual on SPSS." It was one of the boarding officers on the Stratton's primary interceptor vessel, a 26-foot inflatable boat dispatched on Moore's orders. The breakaway boat was closing in on the semi-submersible. "Moving to intercept," the officer said.


In law enforcement circles this kind of self-propelled semi-submersible is known simply as a SPSS, but elsewhere they have come to be known under a more exotic umbrella term: narco subs.

With their stretched, narrowed platforms and planed hulls, narco subs are essentially modified "go-fast boats." They are built in a constellation of makeshift shipyards hidden in Colombia's coastal jungles using a bricolage of local knowledge and over-the-counter technologies. They're almost always made of wood and covered with fiberglass, which effectively waterproofs the vessels. The typical narco sub ranges between 20 and 40 feet long, with one or two gas tanks up front (they can double as sleeping surfaces), followed by the cargo hold, cabin, and an engine and machine room at the rear. A generator that charges batteries and communications gear (GPS, satellite, and ultra high-frequency equipment) usually sits beside the engine. Cargo weight submerges all but the top quarter of these vessels; they travel right at sea level, making them difficult to spot on the horizon.


The July 18 bust. Footage courtesy US Coast Guard

"Typically crews are made up of an experienced sailor, the so-called 'captain' who can also be the person who handles communication with the 'base' or the owners of the shipment," said Javier Guerrero, a University of Edinburgh researcher interested in technological innovations in the illegal drug trade. "Most likely the crew is made up of experienced sailors, and the degree of knowledge and experience and their relationship with the owners of the shipment or the contractor determines the hierarchy inside the narco sub."

It's a striking image: A couple of guys locked in a homemade would-be submarine, for potentially up to two weeks and over 3,000 miles, with off-the-shelf navigational gear, no toilet, seven tons of blow, and a prayer they don't get caught or drown.

"Very few people are willing to make the voyage," Manuel Angel Montoya, a former Colombian drug trafficker who worked for the Cali Cartel in the 1990s, told Motherboard in 2011. "One time, in the shipyard where they had their headquarters, I got to see a submarine crew that was about to leave. They got there with their few belongings, they had a good meal, they were treated incredibly well. All night, they would commend themselves to the patron saint. They would pray. To me it looked like a kamikaze ritual."

They leave from jungle's edge in the middle of the night. Guards, who pretend to be fishing, keep a lookout for other watercraft as the semi-submersibles glide out of port. One crew member is always in charge of the scuttle valve—the kill switch, painted red—for the duration of the journey. He will sink the vessel and the contraband if authorities catch them, because under international law crews are considered castaways and rescued if there is no evidence of a felony.


"It's not that a new model replaced an old one. These days we still find semi-submersibles like the ones they built 5, 6, 7 years ago."

Narco subs have forced a tidal shift in the chess match between international drug cartels and counternarcotics agencies. Over the past two decades, advancements in engineering gave rise to a class of Colombian narco subs that carried bigger and bigger payloads across greater and greater distances while avoiding detection. And where the smuggling vessels were initially limited to coastal waters, they are now almost exclusively caught by law enforcement—when they are caught—in open ocean. They are not fully submersible but can dip under water like submarines, coming up every so often to ventilate, and can travel up to 14 days over thousands of miles. Many narco subs barely leave a wake, deceiving officials who hunt for them.

"If they don't see anything after one or two hours, it's hard to keep looking in the same area," said Hernando Mattos, commander of the Colombian National Navy's Pacific Ocean surface fleet.

Narco subs are just one tool in a constantly evolving suite of smuggling tactics, including traditional go-fast boats, bulk shipping containers, drug mules, and planes. They're inconspicuous in open ocean, but also capable of handling literal tons more contraband than, say, a propeller plane. The average semi-submersible, such as the one Moore was chasing down last month, costs around $1 million or less to build, Mattos said.


Not all criminal organizations are in a position to spend that kind of money on a DIY would-be submarine, but for those that can, narco subs are a viable, attractive smuggling technology. Infamous drug lord Joaquin "El Chapo" Guzman, who slipped out of high-security Mexican prison (for the second time) through a mile-long tunnel last month, is known to have used semi-submersibles to expand his Sinaloa Cartel empire.

According to a detailed report published last year by the US Foreign Military Studies Office, maritime routes accounted for 80 percent of illegal drugs smuggled into the US in 2012, the most recent year for which such data exists. Of those drugs that arrived by sea, 30 percent came in narco subs. The FMSO report even raised the possibility of drug-running semi-submersibles someday moving not just drugs, but cash, weapons, extremists, and weapons of mass destruction.


It took Moore's team under 30 seconds to board the semi-submersible and apprehend the four smugglers, who were all immediately detained aboard Stratton. The eight tons of cocaine packed inside their narco sub is the largest amount of drugs seized from a semi-submersible in Coast Guard history. The estimated street value of the cocaine, which had been chopped into 275 bales, is $180 million.

The July interdiction also marks the first time more than one semi-submersible drug-smuggling watercraft has been seized during a single Coast Guard sea patrol. On June 16, Stratton nabbed a similar self-propelled semi-submersible vessel, this one carrying 5,460 pounds of cocaine. The Coast Guard said since May 2015 Stratton has seized from maritime smuggling vessels over 33,000 pounds of cocaine, worth an estimated $540 million wholesale. Since April, the Coast Guard added, Stratton's crew has halted 15 different maritime drug-smuggling attempts.


Yet semi-submersible interdictions are uncommon. Only 29 such vessels have been nabbed since 2006 in the eastern Pacific, according to the Coast Guard. Only 10 of those vessels were taken intact. The rest were either scuttled by the smugglers, or sank while being towed ashore for forensic analysis by officials.

"A SPSS interdiction is not an everyday occurrence," said Moore, who has been with the Coast Guard for 23 years, and captain of the Stratton since June 9. "They are actually rare."

Guerrero, who is currently finishing a dissertation on the evolution of smuggling technology, told me narco sub use hit a high water mark between 2007 and 2011. That's when Colombian and US Navy officials' radar and aerial infrared detection methods caught up with the illegal vessels, at which point narco sub use appeared to taper off. In the technological arms race between smugglers and counternarcotics forces, Guerrero said, once smugglers sense law enforcement is catching up (or onto) their ways, they must switch things up.

If narco subs are falling out of favor among Colombian gangs, what could explain Stratton's recent double bust? And for every high-profile interdiction how many drug-loaded semi-submersibles successfully slip under the radar and deliver the goods? Like so many uncertainties tied to the drug trade, a hunt for answers begins deep in the jungle.


The raid happened early one morning in late July. Two helicopters carrying agents with the Colombian Naval Command and National Army thumped down on a patch of jungle 200 meters off the coast of La Guajira, near a little town called Dibulla, in Northern Colombia. The agents found the vessel in early stages of construction, with a 25-foot wooden frame that was almost finished.


Admiral Ricardo Hurtado, a commander of the Colombian Navy's task force against drug trafficking who was involved in the operation, believes the builders were set to start covering the frame with fiberglass. Hurtado estimates the La Guajira semi-submersible could have carried four to six tons of contraband. Not much else was found at the site—no trash or personal effects—and no one has been arrested or detained in connection to the illegal operation. Between five and eight people had been working on the vessel, Hurtado said. He couldn't reveal much else because the case is currently under investigation.

Once judicial police and the prosecutor's office gathered evidence from the secret shipyard, the sub was destroyed.

Agents from Colombian Naval Command and National Army try dismantling an unfinished narco sub at a clandestine build site in Northern Colombia. Gif by Jordan Pearson. Video courtesy Colombian Navy Task Force Against Drug Trafficking. Used with permission.

This is where it all began. The first signs of narco subs surfaced in 1993 near San Andrés, an island off Colombia's Caribbean coast, where authorities seized a semi-submersible.

To that point, planes were the preferred means of smuggling cocaine out of Colombia. The aircraft would touch down on secret air strips in Mexico or the US in the heydey of Pablo Escobar, Montoya told Motherboard. Those planes eventually started getting captured by counternarcotics agencies, so the next innovation, beginning in the 1980s, was to drop the contraband from planes, Montoya said. But this led to lots of injuries and deaths. If Colombia's drug gangs wanted to stay ahead of the law and continue reaping profits, they had to change things up.


"Each innovation in drug trafficking comes about when the current method reaches a state of crisis," Montoya said.

Go-fast boats came next. Known as "lobsters" (because they were traditionally used for lobster fishing) these open-air vessels were ideal for drug running because most of them had a central refrigerator that could fit one ton of smuggled goods, Mattos explained. Lobsters evolved with time, using up to five outboard motors to carry four or five tons of cocaine. But the boats left long trails on the water that were easily spotted by surveillance planes. Many of them also sank.

Once again, the smugglers would have to shift tactics if they were to avoid detection altogether. They would have to go down below.

The San Andrés vessel was about seven feet long—small by today's standards—and capable of carrying up to two tons of cocaine, as noted by Byron Ramirez in a tactical brief on the evolution of narco sub engineering published in 2014 in the Small Wars Journal. It was a rough prototype with a top speed of only 10 MPH, though it set in motion a decade of experimentation that would more or less standardize narco sub design as it is today.

As smugglers sought a reliable way to move drugs without being detected by law enforcement radar and aerial surveillance, they began allocating more and more funds to semi-submersible R&D. They would implement better hydrodynamics, increased fuel capacity and autonomy, and fewer above-surface pipes as their designs matured, with the end goal of making narco subs completely invisible to aerial surveillance.


Like the progression of any technology, Colombia narco sub innovation has been iterative, rapid, and not without risk. The first big problem smugglers had to overcome was that the early semi-submersibles generated a lot of heat. The engines also let off smoke. First-generation narco subs were easily spotted, especially during daylight, Mattos said.

To fix that, smugglers made a few key structural changes to the vessels. They started installing exhaust pipelines that went practically to the water, so that smoke touched the water and cooled down on contact. Smugglers also started installing engines with closed-cooling systems by water, as well as serpentines (standard copper tube evaporators). All of this significantly reduced the vessels' heat signature, Mattos explained.

"They can build a house, buy a car, and spend everything. Then they make another trip."

From here, smugglers began making their semi-submersibles more cylindrical like bona fide submarines. The problem with the traditional V shape of a go-fast boat, a shape that many early narco subs took on, is that it rides above the water, in plain view. A cylindrical structure was easier to sink, "leaving outside the water only the part"—fully sealed—"where the crew member is sailing," Mattos said.

Meanwhile, smugglers became more selective when hiring designers and builders. It ultimately depends on the location of a build site and how fast the build needs to happen, although Guerrero, the narco sub researcher, said that construction of a narco sub normally involves a team of 15 to 20 people, including fiberglass, electricity, and engine specialists.


At one point, smugglers went so far as to hire Russian engineers to build a narco sub that would've ended all narco subs. In late 2000, Colombian law enforcement found the Russian-designed sub under construction near the capital city of Bogotá. At nearly 100 feet long and over 10 feet wide, it was unlike anything officials had ever seen. Estimated construction costs were $10 million, and officials believed the double-hulled steel submarine, if completed, may have been able to carry up to 200 tons of contraband and cruise at depths below 300 feet. There's been nothing like it found ever since.


By 2007, narco subs could reach speeds of 11 MPH and could handle up to 10 tons of smuggled drugs worth roughly $200 million wholesale, the SWJ reports. Smugglers had begun installing second engines, some 300-350 horsepower diesels, which increased the amount of contraband the vessels could push. They played with vessel size too, Mattos added, depending on how much cargo they wanted to carry.

The Colombian National Army found a record nine semi-submersible vessels in 2009, plus one of only two completed fully-submersible vessels ever discovered. (The other was found in Ecuador in 2010; estimated construction costs were $6 million and $4 million, respectively, according to Mattos.) The busts prompted officials to set up an anti-drug trafficking task force in the region for the express purpose of rooting out clandestine shipyards. To date, Mattos said Colombian law enforcement has interdicted or captured 86 semi-submersibles, along with the one submersible, in jungle build sites and in open ocean.


"It's not that a new model replaced an old one," said Mattos, who believes Colombian criminal organizations with enough time and money continue to build now-classic semi-submersibles. "These days we still find semi-submersibles like the ones they built five, six, seven years ago. What we can verify is that this modality is decreasing with the years. But they still do it."

In recent years, Ramirez notes in the SMJ, some narco subs have been given an upper lead shielding that further reduces their heat signatures to infrared sensors. Ballast tanks help adjust vessel buoyancy. Onboard GPS navigation systems became cheap and popular for smugglers beginning around 2000, Hurtado said. Similar systems are used today, "just like a car," he added, and smugglers use encrypted satellite phones to file reports and coordinate drug shipments.

Montoya, the former Cali Cartel smuggler, said he thinks future subs will be fully automated and operated by remote control by drug traffickers sitting in offices.

Historically, most of the semi-submersibles seized by the Colombian Navy have been both built and launched on the Pacific, not Carribbean, coast. In 1994 and 1995, after discovering the San Andrés semi-submersible, officials once again found rudimentary narco subs in Northern Colombia, in Santa Marta and Cartagena. But activity in the area seemed to dry up after that, with the bulk of building operations apparently shifting south to the Pacific coast.


The Colombian Pacific coast has a long history of shipbuilding and is a known hotbed for modern narco sub manufacturing. The topographical conditions are ideal for this kind of work. The Pacific coast offers a strategic location in the continental drug supply chain, explained Lieutenant Colonel Julio Roberto Moreno Suarez, chief of police in Bolívar, in Northern Colombia. It's an area of dense jungle amid a maze of rivers and estuaries all leading from remote drug labs to build sites to the sea. Criminal organizations here use an existing network of makeshift shipyards, laid out long ago by natives in the region, to build narco subs. Officials have sometimes found multiple vessels under construction at one Pacific coast shipyard at the same time.

A Motherboard correspondent arranged to visit one of these shipyards, a known narco sub build site near Tumaco, in Southern Colombia's Nariña region, but was stopped just short of the site by armed guards wearing street clothes. It was hard to tell if the guards were affiliated with a drug gang or if they were Revolutionary Armed Forces of Colombia (FARC) guerillas working independently of the drug traffickers. They did not reveal their identities, but addressed one another with nicknames like "The Fat," "Scarface," "Dog," and "Cholo." They had rifles slung around their backs, handguns at the wrist, drinks, and DirectTV to pass the time.


After waiting at a checkpoint for three hours, the reporter was finally told to leave for security reasons. It was an hour walk back out of the jungle.

Near the entrance to a known narco sub build site near Tumaco, in Southern Colombia's Nariña region. Photo: Motherboard

It wasn't so much what officials found last month near La Guajira that stood out, but rather the location of the hidden build site itself—to the far north, not the south. Here, after two decades of relative inactivity, was a sign of narco sub construction in Northern Colombia.

"This is new for us," Hurtado told me. "The coast of La Guajira is dry. It's a desert. There are places where rain hasn't fallen in the last three years. But in this area there is a little jungle. There's vegetation. That's how they hid the construction site."

In theory, it could signal that criminal organizations are positioning narco subs to deliver drugs to Mexico's Eastern seaboard, or even venture into the Atlantic Ocean.

Agents from Colombian Naval Command and National Army uncover an unfinished narco sub at a clandestine build site in Northern Colombia. Video courtesy Colombian Navy Task Force Against Drug Trafficking. Used with permission.

Materials, from generators to screws, wood, fiberglass, and electronics, are hauled into the jungle from port cities like Buenaventura to the south, and Barranquilla to the north, where Hurtado believes the builders at La Guajira sourced their vessel's parts. He said build teams often have prior experience building a semi-submersible and are trying to go independent with a schematic they've lifted and improved upon. But there are different modalities across the country.


"There's some drug trafficking organizations that paid someone to build a semi-submersible to take out the drugs," he said. "Others knew how to build a semi-submersible so they offered the other ones to fill the vessel and take the drugs out to the USA."

When they are completed, narco subs made on either of Colombia's coasts are quietly floated out of the jungle to the mouth of the Pacific or Caribbean Sea, where they are loaded with contraband before setting out into a 7 million square-mile expanse known as the Transit Zone. This swath of water includes the Caribbean Sea, Gulf of Mexico, and the Eastern Pacific, where Stratton has seen action lately. The Transit Zone is vast—roughly half the size of the continental United States—and is the domain of Operation Martillo ("hammer" in Spanish), an international maritime counter-smuggling effort led by US Southern Command's Joint Interagency Task Force South.

To find narco subs in the Transit Zone, cutters like Stratton and other Coast Guard ships involved in maritime counter-smuggling efforts rely on aerial surveillance from a fleet of long-range tracking aircraft flown by US Custom and Border Protection's Office of Air and Marine personnel, who assisted in last month's interdiction.

What is clear, for now, is that Colombian gangs never stopped building narco subs.

Many narco subs have been scuttled even after they successfully delivered to Point B.


"They don't do a round trip," said Mattos, who's heard of narco sub captains and crew members individually earning around $75,000 and $50,000, respectively, per trip. "They just go and deliver the drug. Why risk being found on the way back? Normally they do the trip and sink the vessel. One shipment of drugs covers the whole operation and they even win money."

He estimates that a kilo of cocaine goes for between $1,000 and $1,500 USD in Colombia, and that in Mexico the same kilo of coke sells for between $20,000 and $25,000 USD. (In the US, it jumps to over $160,000.) Based on the lower of those estimates, a 8-ton shipment of Colombian cocaine would go for around $158 million in Mexico.

Resources are finite, however, even in a business with such high revenues. That's why Guerrero and others believe narco subs aren't as disposable as they maybe once were: They make multiple trips, Guerrero told me. He added, in stark terms, that until the efforts of the Colombian Navy force criminal organizations to further adapt the smuggling technology the gangs will need to exploit the experience accumulated by narco sub sailors to keep drugs and money flowing.

Many crew members are impoverished. This explains why they take the risk in the first place, "and think this is the only solution," Hurtado said. One successful trip can land them each enough money to not have to work for a few years. "They can build a house, buy a car, and spend everything. Then they make another trip."


But they may not be so lucky when they make that trip.


When the head of US Southern Command testified before Congress in March 2014, he said that due to asset shortfalls Southcom couldn't pursue 74 percent of suspected maritime drug-smuggling vessels.

"I simply sit and watch it go by," the general said.

The FMSO report, published that same year, claimed that narco subs and similar maritime drug-trafficking tactics are being utilized with "relative impunity." Only one in four vessels were being interdicted at the time, according to the FMSO.

"It's really difficult to have estimates," Guerrero said, due to the way the illicit drug market moves around. "If you want some kind of arms race, smugglers develop a technology and then law enforcement agencies develop another. It's constantly changing."

If Guerrero had to hazard a guess, fewer narco subs go by undetected than in the past, which is not to say they have fallen out of favor among criminal organizations in Colombia. "The [Colombian] Navy knows smugglers keep using narco subs and different kinds of submarines and semi-submersibles," Guerrero said.

Stratton's boarding team pulls bales of cocaine from the semi-submersible seized July 18. Photo: US Coast Guard

If exactly how many narco subs manage to slink past authorities is a matter of speculation, the number of narco subs in existence today is likewise murky. The FMSO reported that potentially dozens of subs are made annually by Colombian criminal groutps like the FARC, Rastrojos, and Urabeños.


"It's hard to know how many vessels are built every year," said Hurtado. He added that the investigation process into how many organizations are attempting to build semi-submersibles is "really complicated," but that Colombian officials believe the number of narco subs being built yearly has been reduced on account of a 2009 law that orders jail time for anyone found guilty of constructing, possessing, or crewing a narco sub.

"We see a lot less compared to years like 2007, 2008 and 2009," he said.

The same goes for the amount of cocaine being made in Colombia, where coca production is on the decline—although Suarez, chief of Bolívar police, said that the country is still a major producer of the drug. In Mexico, the most common offloading point for Colombian narco subs, cocaine seizures in the first half of this year were up a staggering 340 percent over the same period in 2014, according to a report from Animal Politico.

It's enough to make the timing of Stratton's two semi-submersible interdictions and Colombian officials' raid on the build site in La Guajira not seem like sheer coincidence. But with pinched intelligence resources it's difficult to render an accurate snapshot of how drugs are being smuggled from Colombia into Mexico over land, air, and sea.

What is clear, for now, is that Colombian gangs never stopped building narco subs. Perhaps they're launching them less often than before, albeit sending bigger amounts of drugs when they do. Less semi-submersibles going to Mexico than in the past could certainly explain why they're not being interdicted as often. For smugglers and the authorities, it's a win-win.


The top of the semi-submersible was slick from the waves that lapped over it. One of the boarding officers from Stratton's interceptor boat lunged toward the vessel's squat, cylindrical hatch. He couldn't raise it because it was locked from inside, so instead he began to bang on the hatch. He could see people inside, and motioned to them to give up. The trip was over.

The officer screamed to one of his partners for a crowbar, and then made one last heaving crank on the hatch, pulling as hard as he could. The hatch flew open.

¡Afuera! ¡Afuera! ¡Salgan ahora! the lead officer yelled in Spanish. "Outside! Outside! Come outside, now!"

Approximately 2,000 of the 14,000+ pounds cocaine was left inside the semi-submersible as a way to stabilize it as authorities towed it to shore. Stratton managed to tow the sub for 100 nautical miles before it started taking on water. The unclaimed cocaine sank with the sub to a depth of over 13,000 feet.

Update: The US Coast Guard informed me that the 16,000 pounds of cocaine seized during the July 18 semi-submersible bust has been changed to 14,000 pounds, due to a "quantity mistake" in their initial report. This story has been changed to reflect that correction.

With additional reporting by Camilo Salas.

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