Hall Brothers Airspeed Indicator

Available 0-80 MPH/Clamp is included  Hall ASI, easily attached to tubing between 1" and 1-1/2" in diameter with the 12" clamp Designed for low speed aircraft as an airspeed indicator. Used on the Quicksilver and other ultralights. A unique design using a floating disc indicator guided by a stainless steel wire inside tapered plastic tube. Easy to read.   How Accurate is a Hall Wind Meter? National Institute of Standards and Technology. (NIST) has tested them a dual section wind tunnel.  Side by side comparison with true airspeed on one side and the Hall wind meter on the other side.  Hall Wind Meter         True air speed 10.0                              9.9 15.0                              15.0 20.0                              20.4 25.0                              25.2 30.0                              30.6 35.0                              34.6 40.0                              38.9 45.0                              43.1 50.0                              47.6 55.0