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I believe that some attitude indicators, the instrument that functions as an artificial horizon, use counter rotation gyros.
The only reference to this on Alta Vista, was the following;
"Sometimes precession is unwanted so two counter rotating gyros on the same axis are used", from [How a gyroscope works]
http://www.accs.net/users/cefpearson/gyro.htm
It also makes sense when you consider the event.
Consider two counter rotating gyros on a common vertical axle. When you pull the bottom of the axle toward you, the CCW rotating gyro will want to climb on the right-hand side whereas the CW rotating gyro will want to climb on the left-hand side. This duplex gyro will resist the imparted pitching force while at the same time it will not introduce a rolling moment.
[ 07 September 2001: Message edited by: Dave Jackson ]