Military Technology 04/2021

for FLIP decreased from 100 days per year to 30. Furthermore, the people who knew how to use it were retiring. There are things FLIP can do because of its size and stability that simply cannot be duplicated. Because FLIP is so quiet, it was ideally suited to study marine mammals, with hydrophone arrays suspended below the surface and observers on top of the platform to correlate the sounds from the animals with visual observations. FLIP’s Future FLIP will be 60 years old next year. What will the future bring? While it has been around a long time, its research capabilities have been kept up to date. The latest generation of scientific instruments can be installed, or mounted on the hull or on its three booms. But lately, business has not been booming. Rob Sparrock, the programme officer overseeing ONR’s research vessel programme, said FLIP can only make observations in one location. Today, a fleet of smaller unmanned buoys can conduct some of the same data collection, but in multiple simultaneous locations. Researchers from the University of Miami’s Rosenstiel School of Marine and Atmospheric Sciences have developed the Air-Sea Interaction Buoy (ASIB), which can perform many of the same functions as FLIP, but can be deployed in many locations at the same time for a lower cost. “The buoys may not be as capable, but they can be more numerous,” Sparrock commented. Sparrock said a FLIP overhaul has been deemed too expensive – es- pecially considering how many years of additional operations could be achieved – and a replacement would be cost prohibitive. “It would cost about $8 million to make FLIP useable for another five or ten years, but that funding could be better used elsewhere. We came up with lots of creative ideas, but there wasn’t enough inertia or funding to keep it going.” There will not be a 60 th anniversary celebration like there was when FLIP turned 50. However, because of its considerable historical signifi- cance, nobody wants to see it scrapped. “I’d like to see a naval base or maritime museum adopt FLIP, and install the 55-foot section in the upright position so people can see it and actually go on it,” Sparrock suggested. “The other 300 feet can be sunk as a reef for divers.” If Sparrock can find FLIP a home, it will be cause for celebration! stay clear. He says ‘Are you sure? It looks like you are sinking.’” While FLIP’s unique characteristics are immediately apparent, there is also a sophisticated ballasting system that is unseen, and which gives FLIP its ability to transition and remain stable, even in rough seas and high winds. And the unique craft has been involved in some serious science. While originally built for acoustics research, FLIP now conducts more broadly-based science, such as air-sea interaction studies. It has been used to examine ocean circulation, storm wave formation, and how thermal energy is transferred between the ocean and the atmosphere. Scientists can lower hydrophone arrays and other sensors into the water to conduct acoustic measuring; pressure sensors and lasers can measure precise changes in wave height; meteorological sensors can take measurements immediately above the sea surface. Heavy instru- ment packages can be lowered to the deep ocean for various studies. FLIP has been used extensively by the Navy to conduct research in deepwater acoustics and signal processing, and frequently worked with the Navy’s diesel-powered deep diving research submarine, USS DOLPHIN. One of the world’s deepest-diving submarines, DOLPHIN, joined the fleet in 1968 and was decommissioned in 2006. In a cruise off Hawaii in 2001, FLIP moored using a single anchor in water 14,000ft deep, with a 30,000ft-long 1.5in double-braided nylon anchor line between the anchor and FLIP. It took an hour for the anchor to reach bottom after being dropped from the support ship, and the anchor was held on the ocean floor with 12t of anchor chain. Some of FLIP’s research projects have involved multiple platforms and systems. The High-Resolution Air-Sea Interaction Departmental Research Initiative (Hi-Res DRI) project off the California coast also involved moored buoys, research ships and aircraft to study air-sea interaction. Also participating in Hi-Res was R/V SPROUL, a coastal research vessel owned by the State of California and operated by Scripps as part of the University-National Oceanographic Laboratory System (UNOLS) fleet. A twin-engine fixed-wing DHC-6 TWIN OTTER from the Naval Postgraduate School’s Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS), was also among the array of assets devoted to this programme, aimed at developing the next generation of numerical simulation models of the coupling between the ocean-wave-atmosphere systems. Some of the research that used to require a FLIP mission can now be conducted using other means. Funding for some of FLIPs regular cus- tomers has been reduced. From 2008 to 2017, the funded research days A retired US Navy captain, Edward Lundquist covers the naval beat for MilTech from Springfield, VA and is a regular contributor to sister publication Naval Forces. From the Bridge MT 4/2021 · 75 The Floating Instrument Platform, or FLIP, partially submerged in the Pacific Ocean. The 355ft research vessel, owned by the Office of Naval Research and operated by the Marine Physical Laboratory at Scripps Institution of Oceanography (University of California), is celebrating 50 years of operation. (Photo: USN/John F Williams)