Various reports indicated Brown's gravitators were the main experimental focus of the gravity control propulsion research. According to G. Harry Stine and Intel, research on Brown's gravitators became classified immediately after demonstrations of 30% weight reductions. Thomas Townsend Brown had obtained a British patent for high voltage, symmetric, parallel plate capacitors, that he called gravitators, in 1928. Brown claimed they would produce a net thrust in the direction of the anode of the capacitor that varied slightly with the positions of the Moon. The scientific community rejected such claims as products of pseudoscience and/or misinterpretations of ion wind effects.