During autopilot operations, what must a pilot be doing?

For autopilot operations, it is essential that the pilot remains seated at the controls with both the seat belt and shoulder harness fastened. This requirement is in place to ensure the pilot's safety and readiness to take control of the aircraft if necessary. In the event of an autopilot failure or an unexpected situation, being securely fastened allows the pilot to react quickly without the risk of being ejected from their seat or losing positioning.

Maintaining this proper seated position also reinforces attentiveness to flight controls and monitoring of the autopilot systems. Autopilot does not relieve the pilot of their responsibilities; they must remain ready to take over piloting duties at any moment.

The other options suggest scenarios that compromise safety and control. For instance, standing at the controls could impede the pilot's ability to manage the aircraft effectively, and being unbuckled would not meet safety standards. Relying solely on manual controls contradicts the purpose of using autopilot, which is designed to assist pilots in managing flight more efficiently. Thus, proper protocol necessitates that the pilot remains securely seated with their restraints fastened during autopilot operations.