In terms of activation, what is unique about the pusher compared to the shaker?

The correct answer highlights the requirement for activation from both computers, which distinguishes the pusher from the shaker. In aircraft systems, especially in those adhering to rigorous operational standards like Part 135, safety protocols often involve redundancy to ensure reliability. The pusher system is designed to operate with inputs from two separate computers, thereby enhancing its reliability and ensuring that it functions correctly only when both systems agree on the need for activation. This dual-computer activation minimizes the risk of malfunction due to a single point of failure, making it an essential feature in aviation safety protocols.

The other options do not correctly describe the activation process of the pusher system. For instance, the notion that it requires only one computer contradicts the redundancy principle that underpins aviation safety. Similarly, the idea that it can operate independently fails to take into account the collaborative activation process needed for reliable functioning. Lastly, labeling it as semiautomatic does not accurately reflect its specific activation procedure, which is inherently dependent on dual input.