Abstract: A self-contained, recirculating flush liquid, type of water closet for passenger aircraft; wherein, the means for periodically draining the contents of the waste holding tank, comprises an inverted U-shaped tube which is separated at the bend of the U-shape or elbow thereof, into approximately two half-parts. These half-parts are joined by a movable or flexible connection in order that one of the half-parts can be moved relative to the other half-part. One end of the U-shaped tube is rigidly fixed to and projects out from the bottom of the tank; and the other movable half-part has an intake nozzle opening which when it is positioned at the bottom surface of the tank, it is at an operative waste removal position, and when it is moved to a raised position where the intake nozzle opening is at the top of the tank, the removal of waste from the tank is prevented.

Abstract: A recirculating toilet having a bowl and a storage chamber, and recirculating means for recirculating liquid from the storage chamber through the bowl and back into the storage chamber. Filter means is interposed between the storage chamber and the recirculating means for filtering solid particles from liquid flowing from the storage chamber toward the recirculating means. A treatment chamber is interposed between the filter means and the recirculating means, and the treatment chamber has a volume substantially smaller than the storage chamber. Treatment means is provided for destroying bacteria in liquid contained in the treatment chamber (flush water).