A membrane-based air separation module includes an inlet configured to receive supply air, a first hollow fiber membrane configured to substantially remove water from the supply air to form an anhydrous air stream, and a permeate port configured to exhaust the water removed by the first hollow fiber membrane from the air separation module. The air separation module also includes a second hollow fiber membrane positioned downstream of the first hollow fiber membrane configured to receive the anhydrous air stream and substantially remove oxygen from the anhydrous air stream, an oxygen-enriched air outlet configured to exhaust the oxygen removed by the second hollow fiber membrane from the air separation module, and a nitrogen-enriched air outlet configured to supply a stream of nitrogen-enriched air to a fuel tank of an aircraft.