Satisfactory detection of nuclear detonations and observation of the resulting clouds by Radar Set AN/CPS-9 during Operation Redwing at the Eniweok Proving Ground indicated that radar equipment could be used in future nuclear tests for nuclear cloud study, fallout prediction techniques, cloud monitoring, locating ground zero during poor visibility, and measuring detonation yield. The ability of the AN/CPS-9 or other type radars to detect detonations (in the kiloton range) under the adverse atmospheric conditions of an arid climate was unknown. An experiment was designed to indlude radar equipment of two different frequencies (1,300 and 9,300 mc). Test results indicate that Radar Set AN/CPS-9 was superior to the other radars used in detecting and tracking nuclear clouds. The AN/CPS-9 detected fourteen of the eighteen shots in which it participated, including two of the three shots from the 40-mile range, three of the five shots from the 100-mile range, and all line-of-sight shots. Radar Set AN/TPS-1D indicated clouds from two shots at close range; Radar Set AN/MPG-1 indicated no nuclear clouds, but detected detonations by target attenuation. (Author).