What is the main purpose of fire extinguishing systems in aircraft?

The main purpose of fire extinguishing systems in aircraft is to dilute oxygen levels and lower temperatures, effectively suppressing a fire. These systems are designed to act quickly in the event of a fire, typically by releasing fire-retardant agents that displace or dilute the oxygen available to sustain combustion. By reducing the temperature and the concentration of oxygen around the fire, the extinguishing agent helps to control and eventually extinguish the flames, allowing the crew to manage the situation safely.

In contrast, simply alerting crew members of a fire may be part of a fire detection system, but it does not serve to actively control or extinguish the fire. Eliminating fuel sources is a more complex process that is not directly achievable through extinguishing systems, as fires may involve multiple fuel types and sources that are not immediately removable. Preventing mechanical malfunctioning is important for overall aircraft safety but is not the primary function of fire extinguishing systems, which are focused specifically on fire control.