Fire extinguishing device and method in particular for cargo spaces in aircrafts

The fire fighting system (1) installed in an aircraft has two containers (2,3) for an extinguishing fluid (16). The containers are pressurized with nitrogen (17). Fluid may flow directly through pipes (10,11,14) from the first container to the cargo space (13). A filter assembly (7) is connected to the second container and incorporates a water adsorption filter (8) and a solid particle filter (9). A measurement system (6) is connected (19) to a control circuit (4). It has a connection (18) to a control valve (5) releasing fluid into the cargo space.