Category Archives: INTs

In 1967 the United States SIGINT system (USSS) improved the speed of its support to air operations over Vietnam by a quantum leap. The older manual system, HAMMOCK, was replaced by IRON HORSE, a flashy new automated system which could deliver information in seconds rather than minutes. Designed by the National Security Agency, IRON HORSEContinue reading “History of the IRON HORSE system”