Towable instrumentation for use with a hand-deployed Remotely Operated Vehicle

A new class of small, hand-deployable underwater vehicles is playing an increasingly important role in oceanographic science. Due to the small nature of these vehicles, traditional incorporation of oceanographic instrumentation into a vehicle's body can result in a device too massive or cumbersome to deployed by hand. In this paper, we present a towed instrument package, FATTI, as an alternative means of sensor integration for small underwater vehicles, specifically for the Remotely Operated Vehicle (ROV) SCINI. The flexibly attached instrument package is comprised of a 120 kHz scientific echosounder and fluorometer, and was deployed in the McMurdo Sound, Antarctica to map the spatial and temporal dynamics of krill, fishes, and phytoplankton. The tow package proved modular and fieldable, and performed over 100 dives during the 2012/13 and 2014/15 Antarctic field seasons.