Выражение встречается в следующем контексте:
The Craft Captain must ensure that the craft Log Book is signed prior to carrying out the external checks.
CAUTION … TO PREVENT POSSIBLE MISALIGNMENT OF THE SERVO FEEDBACK CIRCUITS, DO NOT MANUALLY ROTATE THE BOW THRUSTERS MORE THAN APPROXIMATELY 10° EITHER SIDE OF THE DATUM MARKS WHEN CHECKING FOR FREEDOM OF MOVEMENT.

Заранее спасибо!