Method and apparatus for dewatering a hydraulic fluid

The present invention provides a method and an apparatus (3 ... 6) for the drainage of a hydraulic fluid of a hydraulic system (2), particularly in the aerospace field, comprising a container (10) having a sorbent, an inlet (11) which the container (10) supplies the hydraulic fluid from the hydraulic system (2) for passing the hydraulic fluid through the sorbent (46) for draining the hydraulic fluid in a desiccation mode of the apparatus (3 ... 6), and a return (12) which the dewatered hydraulic fluid from the container (10) to the hydraulic system (2) in the dehydration mode of the apparatus (3 ... 6) recirculates. By means of the inventive method and of the apparatus (3 ... 6), the hydraulic fluid can be continuously and very quickly drained.