U.S. Geological Survey Open-File Report 2007-1194
Figure 6A. Vector Averaging Current Meters (VACMs) stored in a rack on deck en route to an experiment near California. These instruments are typically deployed in-line as part of a subsurface mooring. The bottom cage contains a Savonious rotor that turns at a rate proportional to the current speed and a vane that aligns with the current (see text for a description of the sampling scheme). The blue paint on the cases and white paint on the rotor and vane is antifouling paint used on instruments deployed near the surface where biological growth might foul the sensors. The steel bands around the center of the case were used to support additional instruments, such as a transmissometer or conductivity sensor.