In article ,
Kyle Boatright wrote:
Many aircraft have a Directional Gyro, which is commonly referred to as the
"DG". I've never heard of a displacement gyro.

In the radio controlled heli scene there are heading hold gyros, which
could be described as displacement gyros I guess? They try their best
to be absolute devices (so they apply rudder until the tail is where
it's supposed to be, rather than simply resisting movement) - it's
done in software - effectively doing an integration on the output from
the actual gyro...

Mark