Remembering Chopmist Hill’s World War II eavesdropping effort
It’s hard to read a newspaper these days without finding a report of sensitive electronic information being intercepted—by governments or criminals, for good or evil purposes. An early and significant government-run electronic eavesdropping effort came to a close 70 years ago, when the conclusion of World War II made the radio listening station at Chopmist Hill in Scituate, RI, no longer necessary.
As Tom Mooney writes in the Providence Journal, in 1940 FCC technician Thomas B. Cave discovered that Chopmist Hill offered miraculous radio reception. The FCC set up a listening station on a Chopmist Hill farm in 1941 with the intent of intercepting transmissions from U.S.-based German spies. But Cave discovered he could receive transmissions from locations as distant as Europe and South America. As the war progressed, the station was able to monitor tank-to-tank communications from Rommel’s Afrika Korps. Ultimately, technicians at the station strung 85,000 feet of antenna wire.
The station, Mooney writes, fulfilled its mission of eavesdropping on German spies in the U.S., and it also fielded distress calls from lost aircraft, including one carrying actress and USO entertainer Kay Francis. In addition, it gleaned information that prevented a submarine attack on the Queen Mary, carrying 14,000 troops from Rio de Janeiro to Australia. The station also intercepted German weather reports to support British bombing raids. And it located explosives-laden balloons launched by Japan—allowing fighter planes to destroy them before they reached the West Coast.
Mooney notes that Chopmist Hill’s remarkable radio reception caused UN inspectors to consider the location for the new UN headquarters. When asked by one of the inspectors what the range of the station was, Cave replied, “Well, Sydney, Australia. That’s about the farthest place there is.”
The UN plans for Chopmist Hill fell through when John D. Rockefeller offered the UN $8.5 million to purchase its current location in New York.
Chopmist Hill was one of several radio listening stations. Signals obtained at other stations offered the ability for triangulation in support of two direction-finding antennas at Chopmist Hill.
