Fuel cell system and method for operating a fuel cell system

An aircraft, comprising:

• a fuel cell system including at least one fuel cell having an air inlet and an exhaust gas outlet, an air supply device connectable to the air inlet, an exhaust gas extracting device connectable to the exhaust gas outlet and a water extraction device having at least two drying units, the water extraction device adapted for selectively providing a fluid connection from the air supply device to the air inlet of the fuel cell through a first one of the at least two drying units and a fluid connection from the exhaust gas extracting device to the exhaust gas outlet through a second one of the at least two drying units;
• at least one fuel tank having an inert gas input,
• wherein the inert gas input is connectable to an inert gas port positioned downstream of the exhaust gas extracting device of the fuel cell system.