Dutch submersible manufacturer U-Boat Worx has successfully completed sea trials of its flagship Super Sub, marking a key milestone ahead of its first client delivery, expected within weeks.

The trials took place off the coast of Curaçao, where the vessel underwent a comprehensive validation programme designed to test propulsion, handling, control systems and onboard safety under real-world conditions. Following the campaign, the Super Sub received full safety certification from DNV, confirming its readiness for operational deployment.

Positioned as the fastest and most technically advanced private submersible ever built, the Super Sub is powered by 100kW of horizontal thrust, enabling it to reach speeds of up to nine knots – a benchmark not previously achieved in the private submersible segment. Its ability to execute inclines and descents of up to 45 degrees allows for agile navigation across complex underwater terrain, including steep reef walls, shipwrecks and deep-sea drop-offs.

Safety and control precision were central to the testing programme. The submersible is equipped with high-accuracy sonar capable of continuously scanning the seabed and autonomously adjusting its trajectory. Redundant life support and control systems were also subjected to rigorous testing throughout the trials.

With an operational depth of 300 metres and a range of up to 10 nautical miles, the Super Sub is designed to enable extended underwater exploration within a single dive. This includes applications such as reef surveying, wreck mapping and detailed inspection missions.

The vessel features a fully transparent acrylic pressure hull, offering panoramic visibility for both pilot and passengers. Its cockpit has been ergonomically designed to provide intuitive, aviation-style controls, enhancing both usability and situational awareness during dives.

Sea trials also produced a library of high-resolution photography and cinematic footage, demonstrating the submersible’s performance and visual capabilities in open-water conditions.

With certification secured and testing complete, U-Boat Worx is now preparing to deliver the Super Sub to its first client, marking the commercial debut of a new generation of high-performance private submersibles.