Which block on the AFTO Form 781 is NOT the responsibility of the maintenance crew chief?

The flight crew block on the AFTO Form 781 is not the responsibility of the maintenance crew chief because it pertains specifically to the operational side of the aircraft and records information about the personnel who are flying the aircraft. The flight crew is responsible for conducting flight operations, and documenting their own details in this block.

On the other hand, the MDS block, unit charged block, and host Aviation Resource Management (HARM) location block all relate to maintenance and logistics, which fall under the jurisdiction of the maintenance crew chief. The MDS block indicates the Model Design Series of the aircraft, the unit charged block shows the unit responsible for the aircraft, and the host HARM location block relates to the management of aviation resources at the installation these responsibilities all directly involve the maintenance function and the management of aircraft readiness, which is guided by the maintenance crew chief.