In 1961, SAC and the U.S. Army began a joint training mission with benefits for both parties. SAC needed fresh (simulated) targets which the cities ringed by Nike/Hercules sites provided, and the Army needed live targets to acquire and track with their radar. SAC had many Radar Bomb Scoring (RBS) sites across the country which had very similar acquisition and tracking radar, plus similar computerized plotting boards which were used to record the bomber tracks and bomb release points. Airmen from these sites were assigned TDY to Nike sites across the country to train the Nike crews in RBS procedures. The distances from the simulated bomb landing point and the "target" were recorded on paper, measured, encoded, and transmitted to the aircrews. The results of these bomb runs were used to promote or demote air crews. ECM activity also took place between the bombers and the Nike sites. The performance of the NIKE crews improved remarkably with this "live target" practice.