turn coordinator
 

How does turn coordinator read both rate of roll and rate of turn from the reading?

the indication is same as that of old turn and bank indicator.

A turn indicator has a gyro with an axis aligned with the longitudinal axis of the aircraft(from nose to tail). This means that it can only sense yaw.

A turn co-ordinator has the gyro axis tilted 'up' by 45 degrees, so it will sense both yaw and roll.

The indications are slightly different. The turn indicator is a needle whereas the turn co-ordinator is represented by a 'little aeroplane' viewed from the back.

Which is why the Turn Indicator is good for a spin recovery on instruments. It tells you the direction of spin whereas the Turn Coordinator is useless and because of the yawing motion during a spin the `little aeroplane` can indicate a turn in the opposite direction to the actual spin.. Confusing if IMC.

i mean how would u separate the reading of both rate of roll and rate of turn at the same time from the same instrument.

The most convenient place I could find online with a diagram was wikipedia. Just search and click. Or go to FAA.gov and download from the airplane flying handbook.

It's the orientation of the gyro rotor assembly within the instrument case.The turn coordinator is a hybrid of a yaw rate gyro and a roll rate gyro. One advantage of this arrangement is that the instrument displaces in the correct direction during roll in to a turn. Center the inclinometer ball to achieve calibrated accuracy.

Bit of an exaggeration from you Centaurus - the turn coordinator is perfectly accurate in an upright spin, although it can't be trusted in an inverted spin. Hardly a problem for the 99% of us...