> He mentions that axial forces are taken into account If he does, he's not included it in his theory paper. Take a look, there is no mention of "axial forces"

> He mentions that axial forces are taken into account If he does, he's not included it in his theory paper. Take a look, there is no mention of "axial forces" or "deflection" in the paper. In equation 7, he calculates the thrust T using only the difference in propagation velocity at each plate, but makes no mention of how the propagation velocity changes. If he did, it would be obvious that you have to account for radiation pressure on all sides on the tube, not just sides which happen to be perpendicular to the tube's axis. > efficiency in the conversion from electrical energy to momentum The efficiency will be about 0%, so no need to worry.