What is the first step to manually shutdown the engine?

To manually shutdown the engine, the first step involves gaining access to the engine itself, which is why entering the Left or Right Main Landing Gear (MLG) area is essential. This action allows the personnel to be in close proximity to the engine controls and shutdown mechanisms. Once inside this designated area, they can then proceed with the appropriate shutdown procedures, ensuring they are in a safe and regulated environment.

The other options focus on steps that might come later in the shutdown process or are part of safety measures rather than the initial action required to start the shutdown sequence. Disconnecting the battery, for example, is a crucial step for safety but is typically done after initial access and after evaluating all necessary procedures. Opening the engine cover is a task involved in preparing for shutdown but must be preceded by confirming access to the engine area. Setting the emergency shut off is certainly a vital step, but it cannot occur until the individual is in the appropriate position to enact it.