Among the truly unique creations in this world is the Floating Instrument Platform, or FLIP, a research vessel designed for the US Navy. Unlike any other, FLIP had the extraordinary ability to sink itself vertically for scientific research.
In the 1960s, sailors off the US West Coast might have encountered an alarming spectacle: a ship seemingly sinking in a dramatic Titanic fashion. On closer inspection, instead of a scene of distress, they would find a crew member leaning on a rail, indicating that everything was under control.
This scenario was a common occurrence during the over 60-year service of the FLIP. At first glance, FLIP appeared odd in port, but once at sea, its transformation was even more surreal. Measuring 355 feet long with a beam of 26 feet and displacing 700 gross tonnes, FLIP resembled a giant steel asparagus stalk with a conventional ship’s bow. This unique vessel, designed by Allyn Vine of the Woods Hole Oceanographic Institution, was launched on June 22, 1962, after two years of design and testing.
FLIP could not sail under its power and required towing to its station by a tugboat. Initially, it drew only 12.6 feet, but once on-site, it would fill its aft end with water, causing the vessel to tip vertically. This transformation changed its draft to a record-breaking 300 feet, turning FLIP into a stable floating laboratory ideal for scientific research.
The primary purpose of FLIP’s unique design was to aid the US Navy in developing the UUM-44 SUBROC, an anti-submarine weapon capable of launching a depth charge from a torpedo tube. The challenge was to gather underwater data on SUBROC’s performance, which required precise acoustic measurements—a task hindered by the complex acoustics of the ocean. FLIP provided a stable platform for such measurements, unaffected by surface waves and capable of deploying sensors at various depths.
FLIP’s design allowed it to support an array of underwater sensors on a steady platform. The vessel’s interior was equipped to function in both horizontal and vertical orientations, although this made life aboard quite unusual. While being towed, the crew experienced a topsy-turvy environment with doors and bulkheads out of place and wash-stands halfway up the walls. Despite these quirks, FLIP’s innovative design included trunnion-mounted engines and flexible exhaust couplings to accommodate its unique flipping capability.
With a crew of five and up to 11 scientists, FLIP operated primarily from the Scripps Marine Physical Laboratory in San Diego, California. It ventured to locations such as Hawaii and the US East Coast, collecting data on wave height, acoustic signals, water temperature, and meteorological conditions. This data contributed to fields such as geophysics, meteorology, and physical oceanography.
FLIP’s last research mission was in 2017. Despite considerations for a new refit, the high cost led to its decommissioning in August 2023, concluding its remarkable service.
