Paul,
Isn't the DGI a tied gyro as well as being a displacement gyro. Its a tied gyro because the spin axis is tied to the aircraft's horizonal?
The AI as well as being a displacement gyro, isn't it also a special type of tied gyro called an Earth gyro becuase its tied to the earth's vertical?
Are these correct?
Thanks Paul for answering my thread concerning rate gyros. I'm still having problems with regard to Rate Integrating Gyros found in turn indicators!!