Lockheed Martin Sippican's XBT system consists of an array of expendable probes, with a MK21 USB Data Acquisition Set and a portable, Hand Launcher.
The system uses a sea water ground; upon contact with the water, temperature data can be telemetered to the ship-board data processing equipment. The nose of the probe is precision weighted; probe depth is determined to an accuracy of +2%. When the probe reaches its rated depth (a function of ship speed and the quantity of wire contained within the shipboard spool) the profile is completed and the system is ready for another launch.
A precision thermistor is located in the nose of the probe. Changes in water temperature are recorded by changes in the resistance of the thermistor as the XBT falls through the water. It is capable of temperature accuracies of +0.1°C.
T-4 XBT Probe
T-5 XBT Probe
T-6 XBT Probe
T-7 XBT Probe
T-10 XBT Probe