Airspeed indicating system.
13. Airspeed indicating system. Each airspeed indicating system must meet the requirements of FAR 23.1323 and in addition -
(a) Airspeed indicating instruments must be of an approved type and must be calibrated to indicate true airspeed at sea level in the standard atmosphere with a mimimum practicable instrument calibration error when the corresponding pilot and static pressures are supplied to the instruments.
(b) The airspeed indicating system must be calibrated to determine the system error, i.e., the relation between IAS and CAS, in flight and during the accelerate takeoff ground run. The ground run calibration must be obtained between 0.8 of the mimimum value of V1 and 1.2 times the maximum value of V1, considering the approved ranges of altitude and weight. The ground run calibration will be determined assuming an engine failure at the mimimum value of V1.
(c) The airspeed error of the installation excluding the instrument calibration error, must not exceed 3 percent or 5 knots whichever is greater, throughout the speed range from VMO to 1.3S1 with flaps retracted and from 1.3 VSO to VFE with flaps in the landing position.
(d) Information showing the relationship between IAS and CAS must be shown in the Airplane Flight Manual.