On Saturday, July 23, 2016 at 8:02:09 AM UTC-5, Doc wrote:
A novice question for the skymasters. When ballasting my Schleicher should I completely remove the plastic cover-plate over the drain on the undersurface of the wing, or should I leave the cover attached with the tape hinge at the front and detached at the rear with cover-plate hanging down knowing that the airflow will close it in flight and then expecting the water flow to open it when dumping?

The latter, leave the flap in place.