A very detailed patent application by Shawyer is published today.
It is ready for examination.
note that an article in IBT will feature an interview of Roget Shawyer this weekend.
A superconducting microwave radiation thruster used to accelerate a spacecraft or an airborne vehicle comprises a tapered central sectuon 2 with a minor end plate 1 at one end and a major end plate 3 at the other end. The minor end plate is specially shaped and attached to the tapered section with both parts being formed of non-superconducting material. The major end plate 3 is flat and made of superconducting material and is attached to the tapered section by screws. A single crystal sapphire substrate 4 is glued to the major end plate. Thrust is generated via a thrust plate 11 that is connected via a thermal insulator 10 and cooler 7 to the major end plate. The geometry is intended to simplify the manufacturing of the thruster. The thruster includes circularly polarised input and detector antennae which, when combined with a phase locked loop control circuit, enable the input frequency to be corrected for Doppler shifts, caused by acceleration of the thruster. These Doppler shifts would otherwise cause a decrease in cavity Q value, and thus a decrease in output thrust.