Which support vessel surveyed deep sites for Limiting Factor dives?

The support vessel that surveyed deep sites for Limiting Factor dives was DSSV Pressure Drop.

DSSV stands for Deep Submergence Support Vessel. During Victor Vescovo’s Five Deeps Expedition, Pressure Drop carried the full-ocean-depth submersible DSV Limiting Factor, deployed it through an A-frame, and supported recovery after dives.

The ship also carried a Kongsberg EM124 multibeam echo sounder used to map trenches and identify promising deep points before submersible operations. Three robotic landers helped record environmental data and document the seafloor independently of the crewed vehicle.

Pressure Drop supported dives across all five oceans, including Challenger Deep, the Tonga Trench’s Horizon Deep, and the Arctic Ocean’s Molloy Deep. In 2022, the vessel and Limiting Factor were sold to Inkfish; Pressure Drop was renamed Dagon and the submersible became Bakunawa.