A dehumidification system for removing water vapor from the within the envelope of an airship comprises a pressurizer valve, a blower and a dehumidifier attached to the airship. The pressurizer valve releases air from the envelope and directs the air to the blower. The blower forces the air through the dehumidifier where the air is dried to a desired dew point. The dried air is then forced back into the envelope of the airship, thus reducing the weight of the airship and reducing the amount of condensate that may form during an ascent.