Where does airspeed indicator come alive?

[avidflyer]

If you get some 1/4" ID plastic hose you can check the ASI without damaging it. I would take a piece about 10' long, and slide one end over the pitot tube. Plug the other end of the tube and start folding up the tube while watching the ASI. Folding the tube increases the pressure in the line, and the ASI should go up. If you were to have a T in the hose connected to a manometer, you would get a reading and with that, you can check the accuracy of your ASI. I've found that most of our cheaper ASIs read high. Here is a link to an article discussing this. Airspeed Indicator Calibration (n56ml.com) He is using a real water column, a manometer is an electronic device that will do the same thing but easier. Any gas furnace installer will have one, and I got mine off ebay for about $30. Used this method and added labels to the face of the ASI showing calibrated readings, my ASIs in both planes are spot on according to GPS readings when flown in opposite directions and then average the speeds. JImChuk