Lockheed Martin Sippican eXpendable BathyThermograph/eXpendable Sound Velocimeter Sippican XBT/XSV Lockheed Martin Sippican, Inc. https://www.lockheedmartin.com/content/dam/lockheed/data/ms2/documents/ocean/20050054_XBT_XSV_reader_page.pdf Lockheed Martin Sippican eXpendable BathyThermograph/eXpendable Sound Velocimeter Lockheed Martin Sippican eXpendable BathyThermograph/eXpendable Sound Velocimeter information information resourceProvider Sippican XBT/XSV Temperature, Depth, Sound Velocity The Expendable Bathythermograph is used by scientists to provide an ocean temperature versus depth profile. Useful for oceanographic research, the XBT does not restrict ship mobility. The Expendable Sound Velocimeter obtains accurate sound velocity profiles for the support of ASW operations, mine countermeasure operations, and oceanographic research.