The Turn Indicator is an instrument measuring an angular velocity within ±3°/s of the aircraft vertical axis which corresponds to parameters of the turn performed at speed of 190 kts (350 km/h) at a bank of 45°. The Turn Indicator incorporates a liquid level indicating a slip during the turn. Reaching the gyro’s operating speed is indicated by the OFF sign on the turn indicator dial disappearing. The deflection greater than corresponding to an angular velocity of ±4°/s is limited by a dead stop. The instrument is manufactured in version coordinator too. There is also a version with an illuminated instrument face (supply voltage: 5, 14, 28 VDC - according to customer requirements). This instrument fulfills the requirements and methodology rules TSO – C3d and RTCA/DO – 160D.