A small, unmanned watercraft of unknown origin washed up from the Black Sea on the shore of Crimea, near Russia’s naval base in Sevastopol, late last month.
Pictures posted on Russian social media show what appears to be a small, novel surface drone made from commercial watercraft parts laden with explosives that could explain recent Russian Navy trends to keep their warships in port over the last three weeks.
The unmanned surface vehicle was not identified by national markings, but the character of the USV and the Russian reaction to destroying the watercraft suggest that the drone originated in Ukraine.
The photographs published on social media reveal key components of the USV that give better clues to its function.
Analysis of photos of the vessel reveals that it is propelled by a recreational water jet. The waterjet has been specifically identified as closely matching a Sea-Doo design, down to the
“No Step” sticker on the housing. The lines of the thrust reverser show that it is a relatively recent model, possibly a GTX or Fish Pro model, based on the images.
Sea-Doo is a Canadian manufacturer of personal watercraft. The company sells its products worldwide, aimed mostly at the civilian market. This means that a Sea-Doo would be relatively easy to source.
The external clues did not provide strong hints about the power plant. But some Sea-Doo models feature high-performance three-cylinder gasoline engines from Rotax that can drive the watercraft up to 70 miles per hour. Some recreational watercraft can be diesel or electric, but gasoline seems the most to be compatible with the Sea-Doo water jet.
Another key feature of the USV is the likely detonation method for the drone. On the bow, two projections have been provisionally identified as impact fuses. These are similar in appearance to fuses on aerial bombs, such as the Soviet-era FAB-500 family, which are still widely used today.
The fuses would likely be connected by a cable to the detonator and warhead. The size and location of the warhead is unclear, but would likely get loaded in the front half of the craft.
While personal watercraft are generally made from fiberglass, or similar materials, the explosive USV appears to be constructed from aluminum based on the appearance of the boat from the social media photos.
Last month, a Pentagon spokesman would not confirm if the USV the unidentified coastal defense USVs the United States provided to Ukraine earlier this year.
Not The First Explosive USV
Other groups, notably the Houthi Movement in Yemen and Al Qaeda, have used USVs as explosive boats in recent years. The Iran Revolutionary Guard Corps Navy may have assisted the Houthis in the design and use of the USVs, USNI News has previously reported.
In 2017, two sailors aboard Royal Saudi Navy frigate Al Madinah (702) were killed by a drone boat attack blamed on the Houthis, U.S. 5th Fleet confirmed at the time.
But previous explosive drone boats have been adaptations of crewed boats and retain a pilot position for longer transits. Due to its size and lack of pilot station, the suspected Ukrainian craft stands out as being completely uncrewed. The smaller size presents a lower profile, which makes it harder to spot and counter.
The revelation of the new explosive USV could explain the lack of Russian Navy operations near Sevastopol and around Crimea. Since the mystery USV was discovered in late September, the Russians have retreated into the defended harbor of Sevastopol, have reduced the number of warships lurking outside the entrance to the port and used a boom across the mouth of the harbor to control access more often, according to ship spotters.
The Russian Navy only started active patrols in the Black Sea from Sevastopol after the attack on the Kerch Strait Bridge on Oct. 8.