In 1956, the Gravity Research Group (a Special Weapons Study Unit based in London) prepared a classified report for the U.S. Air Force titled "Electrogravitics Systems: An Examination of Electrostatic Motion, Dynamic Counterbary and Barycentric Control" (Report GRG-013/56). EXCERPT FROM REPORT: "This report summarizes in simple form the work that has been done and is being done in the new field of electrogravitics. It also outlines the various possible lines of research into the nature and constituent matter of gravity, and how it has changed from Newton to Einstein to the modern Hlavaty concept of gravity as an electromagnetic force that may be controlled like a light wave The report also contains an outline of opinions on the feasibility of different electrogravitics systems and there is reference to some of the barycentric control and electrostatic rigs in operation"