Which load is associated with aircraft attitude changes and gyroscopic effects of heavy rotating masses?

• A. Weight Of The Rotating Mass
• B. Gyroscopic Effect Of Heavy Rotating Masses Trying To Remain In Place As The Aircraft Changes Direction
• C. Thermal Expansion
• D. Vibration From Air And Engine

Answer: (B)

Attitude changes can produce gyroscopic loads when the engine has heavy rotating masses, like turbines or fans, because these parts resist changes to their spin orientation. A rotor has angular momentum, and changing the direction of that spin requires a torque. That torque shows up as a load on the engine mounts and structure, directed perpendicular to both the rotor’s spin axis and the direction of the attitude change (known as gyroscopic precession). The faster and heavier the rotating mass, the larger the load. The other options don’t capture this dynamic: weight is a static downward force, thermal expansion relates to temperature changes, and vibration from air and engine is a general dynamic issue not specific to gyroscopic reaction during attitude changes.