The ASI-3 airspeed indicator is a 3-1/8" instrument that provides a wide range airspeed indication in both digital and analog formats. Airspeed is based on the pressure generated by a pitot tube system and a static port is provided as well for use by high speed aircraft. In addition, the ASI-3 provides a 24 entry automatic flight log that stores the duration of each of the last 24 flights, an air-distance trip counter and a current flight timer. Airspeed can be indicated in statute miles per hour (mph), kilometers per hour (km/h) or nautical miles per hour (knots) with the air-distance being displayed in corresponding units. The analog airspeed display can be scaled according to the aircraft’s flying speed range and markers for Vs, Vf, Vno and Vne can be set. ASI sensitivity can be calibrated by the user to cater for errors caused by pitot tube placement. The ASI-1 instrument measures airspeed from 16mph to 250mph and is well suited to slower aircraft due to very good sensitivity and linearity at low air speeds.