What does pulling the firewall shutoff handle cut off?

Pulling the firewall shutoff handle primarily cuts off fuel to the engine. This safety mechanism is designed to prevent fuel from reaching the engine in the event of an emergency, such as a fire or a fuel leak. It effectively isolates the fuel system from the engine, allowing pilots to manage critical situations where controlling fuel supply is essential for safety.

While the options suggest that the handle could affect hydraulic fluid or bleed air as well, its primary function is to stop the flow of fuel. Understanding this aspect is crucial for pilots, as knowing how to quickly and effectively shut off fuel can help mitigate fire risks and manage emergency procedures during flight operations.