Which action will not operate the cargo doors?

Using manual locking alone will not operate the cargo doors. Manual locking refers to the mechanism that secures the doors in their closed position but does not initiate the opening or closing process. The cargo doors require hydraulic pressure, electrical power, or the use of a hand pump to function.

Hydraulic pressure serves as the primary method for operating the doors, while electrical power can control the hydraulic systems or activate the doors directly. The hand pump can also be used in situations where hydraulic power is unavailable, allowing for manual operation. In contrast, simply engaging the manual locking mechanism does not provide the necessary force or function to move the doors, making it ineffective for their operation.