A method of managing evaporated cryogenic fuel in a storage tank of a cryogenic fuel system of an aircraft and an aircraft having at least one turbine engine providing propulsive force for the aircraft and a cryogenic fuel system including a passively cooled cryogenic fuel storage tank located within the aircraft, a pressure vent fluidly coupled to the cryogenic fuel storage tank and exhausting evaporated gas from the cryogenic fuel to define a natural gas vent stream, and a catalytic converter fluidly coupled to the pressure vent.