It was an urban legend at its best, South American drug cartels were running narcotics in the early 90s destined for the United States in small, radar-dodging, self-propelled, semi-submersibles (SPSSs).
Word hit the street the clandestine semi-submersibles supposedly existed in the mid-1990s. Urban legend? No way. In 2006, an actual Colombian semi-submersible ended up captured by the U.S. Coast Guard in the Eastern Pacific Ocean. Today, drug cartels continue to build their “narco subs.” With low profiles and low radar reflectivity, these illegal, stealthy, drug-running semi-submersibles cut through the water at wave height and are nearly impossible to detect.
In an effort to fight back, the Department of Homeland Security Science and Technology Directorate (S&T) built its own submersible called PLUTO in 2008 to serve as a surrogate SPSS with many of the same features as the vessels built by the cartels. It is a target by DHS and its national security community partners to help test the performance of detection systems and give operators of those systems real world experience under controlled conditions. This testing helps develop new concepts of operation for seaborne, airborne, and space-borne technologies to spot illegal vessels.
“Small surface vessels, self-propelled semi-submersibles, and now the most recent innovation of fully submerged vessels (FSVs), pose significant challenges to maritime security,” said Tom Tomaiko of S&T’s Borders and Maritime Security Division. “While some small boats sitting low in the water have legitimate purposes, there are many that are used for illicit purposes.”
U.S. officials have captured dozens of these boats, sometimes with their cargo still on board, sometimes after they threw it overboard. “When the crews become aware they’ve been spotted, they will typically scuttle the boat immediately, knowing they’ll be rescued by us anyway,” Tomaiko said.
Meanwhile, cramped living conditions within the illegal SSPSs can be horrendous. There is generally only 3″ of space above the waterline, meaning the ride can be very rough. The small crews of 3 or 4 have little to eat, poor air quality, no toilet facilities, operate with little rest until they reach their destination, and sometimes armed guards watch over them.
If the mission is a success the drugs delivered, the vessel typically ends up scuttled and not reused. “Drug-running is lucrative. It is cheaper to simply build another vessel than to run the risk of trying to get a vessel and its crew home,” Tomaiko said.
In a typical operation, PLUTO will operate at SPSS cruising speeds of 4 to 8 knots while remote sensor platforms from sea to space attempt to detect and track it at various distances and observation angles.
PLUTO is just over 45 feet long, can run roughly 10 knots at maximum speed and can hold a crew of 3 to 4, although it usually operates with only one for safety reasons. It has VHF and HF radios, and the 46th Test Squadron can install other types of radios and maritime automated identification system (AIS) equipment to meet testing or safety requirements. Conditions onboard, however, focus on the need for crew safety, so PLUTO’s design does not exactly mimic that of illegal SSPSs.
Technical capabilities such as PLUTO are necessary to counter and stay ahead of threats to the country. Admiral James Stavridis, former Joint Commander for all U.S. forces in the Caribbean, Central and South America, said, “Criminals are never going to wait for law enforcement to catch up. They are always extending the boundaries of imagination, and likewise, we must strive to push forward technology and invest in systems designed specifically to counter the semi-submersible. We need to be able to rapidly detect and interdict this new type of threat, both for its current effects via the drug trade, and – more troublingly – for its potential as a weapon in the hands of terrorists.”