Recent developments of transition radiation detectors utilizing super-conducting grannles are described. These include (1) a sigificant improvement in the sensitivity of the TRD system by means of a newly developed ferrite transformer, and the extension of the length of each U-shaped coil loop into a multiturn structure; (2) successful development in man producing superconducting grannles of uniform sizes and without magnetic defects, by several methods, and (3) applications of the superconducting grannles in precision industrial tests of the dynamic x-ray profile of the motions of the components of airplane engines during actual operation, as well as TRD in the detection of solar neutrions and magnetic monopoles.