| 73 / | HD | MEASURING AND TESTING |
| 488 | DF | SPEED, VELOCITY, OR ACCELERATION {29} |
| 504.02 | DF | .~ Angular rate using gyroscopic or Coriolis effect {4} |
| 504.08 | ![]() | .~.~ Rotary gyroscope {2} |
| 504.09 | DF | .~.~.~> Gimbal support |
| 504.11 | DF | .~.~.~> Flexible rotor or flexibly mounted rotor |