What do T/L handles do and why is the battery last in the sequence?

• A. T/L handles open fuel flow and deactivate the fire-protection system; battery is first because electrical systems are last.
• B. T/L handles stop fuel flow and arm the fire-protection system; battery is last because the bottles/fire system is electrical.
• C. T/L handles stop fuel flow only; battery is last due to the bottles being electrical.
• D. T/L handles arming the fire-protection system; battery is first because it powers the pumps.

Answer: (C)

The action to focus on is fuel isolation. T/L handles are there to stop the fuel supply to the affected engine, which helps prevent feeding the fire and protects the engine from continuing to burn. They don’t arm or deactivate the aircraft’s Fire Protection System; that function is handled by separate controls in the cockpit.

Why the battery is last: the fire-suppression bottles are activated electrically, so power to release the agent is applied after you’ve secured the fuel supply. By commanding fuel shutoff first, you reduce the fire’s fuel source and then energize the system to discharge, which is a safer, more controlled sequence. This ordering avoids unnecessary or premature activation while fuel could still be flowing.