A US Navy Coastal Patrol Vessel and an MH-60 Sea Hawk from the 5th Fleet stopped a ship of Iran’s Revolutionary Guards Corps Navy from committing an act of piracy on the high seas of the Arabian Gulf yesterday.

An Uncrewed Surface Vessel(USV) known as the Saildrone Explorer is a scientific research platform used to measure air-sea exchanges of heat and carbon dioxide, ocean dynamics, and to assess populations of fish and the condition of marine mammal populations.  It is human-controlled by satellite and uses a sail to travel at 4-6 knots.  It’s instruments are powered by solar panels. The Saildrone Explorer is equipped with an automatic identification system (AIS) transceiver, navigation lights, radar reflector, high-visibility wing colors, and four onboard cameras to ensure its safe navigation in open waters.  It is not a spy ship and is visible to other vessels operating in the sea lanes of the world’s oceans. At 23 ft long with a 15 ft sail, the USV is about the size of a small bright orange sailboat.

On August 30th, the Saildrone Explorer was intercepted by the Shahid Bazier a supply ship of the IRGC Navy of Iran, which presumably boarded the vessel and took it undertow in an act of piracy. With cameras aboard the operators ashore were able to alert the 5th fleet that the Saildrone had been seized by the IRGC ship.  The SailDrone Explorer was operating under contract with the US Navy to do oceanographic research on winds, currents and water temperatures.

Soon the Cyclone class patrol ship, USS Thunderbolt intercepted the Iranian vessel aided by a Sea Hawk helicopter from Helicopter Sea Combat Squadron 26 “Chargers” out of Bahrain. The MH-60S “Knighthawks” as they are unofficially known can carry a variety of weapons including two M-60N machine guns, four to 8 AGM-14 Hellfire missiles, 2 Mk54 torpedoes or 16 APKWS Hydra missiles.

USS Thunderbolt (PC-12) is the 12th Cyclone class Patrol (coastal) ship operated by both the US Navy and Coast Guard under dual commissioning program that allows the two services to transfer the vessels between themselves for various missions of national defense or maritime law enforcement at sea. The primary mission of these ships is coastal patrol and interdiction surveillance.  They can make more than 35 knots of speed and are heavily armed with two Mk 38 25mm mounts; two .50 cal. machine guns, six Stinger missiles, two Mk 19 automatic grenade launchers, and a Mk 52 Mod 0 chaff launcher.

They are crewed by 28 sailors and also carry 8 members of a Naval Special Warfare Detachment(SEALS) for boarding operations and other missions.

The appearance of the presumably armed Knighhawk and the Patrol craft were enough for the Revolutionary Guards vessel to sever its tow line and leave the area without further incident.

In a navy press release, Vice Adm. Brad Cooper, commander of U.S. Naval Forces Central Command, U.S. 5th Fleet and Combined Maritime Forces stated, “IRGCN’s actions were flagrant, unwarranted, and inconsistent with the behavior of a professional maritime force,” He went on to state that US naval forces would persist in sailing international waters, “U.S. naval forces remain vigilant and will continue to fly, sail and operate anywhere international law allows while promoting rules-based international order throughout the region.”

This measured statement holds well short of accusing Iran of an act of piracy on the high seas by taking a vessel belonging to the US under tow and attempting to take it back to Iran for study.

Support ships like the Shahid Bazier operate in open waters to sustain the IRRG’s fleet of small high-speed boats of the IRGC navy far from shore in the Persian Gulf, the Gulf of Oman and the Arabian Sea.  It is a lightly armed vessel with only a single anti-aircraft gun and some light machine guns.


17 March 2014 USS Typhoon (PC 4), plus (left to right), USS Monsoon (PC 5) and Thunderbolt of Coastal Patrol Squadron ONE (PCRon 1) carry out a divisional tactics exercise while forward deployed to the Fifth Fleet. PCRon 1 is deployed supporting maritime security operations and theater security cooperation efforts in the U.S. 5th Fleet area of operations U.S. Navy photo 150317-N-SF508-314 by Mass Communication Specialist 2nd Class Charles Oki



ARABIAN GULF (Aug. 30, 2022) A video showing support ship Shahid Baziar, from Iran’s Islamic Revolutionary Guard Corps Navy unlawfully towing a Saildrone Explorer unmanned surface vessel in international waters of the Arabian Gulf as U.S. Navy patrol coastal ship USS Thunderbolt (PC 12) approaches in response, Aug. 30. (U.S. Navy video)