If a cabin fire occurs during flight, what should be done with the master switch?

In the event of a cabin fire during flight, turning off the master switch is a critical action. The master switch controls the electrical system of the aircraft, and by turning it off, it disconnects the electrical power to the cabin. This step helps to minimize the risk of further ignition from electrical sources and reduces the chance of spreading the fire.

Additionally, shutting off the master switch can help in safeguarding essential systems that could be affected by the fire. This step, combined with other emergency procedures like using fire extinguishing equipment and attempting to locate and eliminate the source of the fire, enhances the chances of effectively managing the situation and ensuring the safety of everyone on board.