About this Unit
The 6990th Security Group was a United States Air Force signals intelligence (SIGINT) unit activated in 1965 at Kadena Air Base, Okinawa. Its primary mission was to provide electronic surveillance and intelligence support during the Vietnam War and throughout the Cold War in the Pacific region. The group operated RC-135 reconnaissance aircraft and other intelligence-gathering platforms, intercepting and analyzing communications from adversaries. The 6990th Security Group remained active until it was inactivated in 1993 as part of post-Cold War restructuring of Air Force intelligence assets.
Historical Facts
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Origins: The 6990th Security Group was established in 1967 at Kadena Air Base, Okinawa, Japan, as a United States Air Force signals intelligence (SIGINT) unit.
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Mission: Its primary mission was to conduct airborne and ground-based signals intelligence operations, especially during the Vietnam War and throughout the Cold War era.
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Crewed RC-135 Aircraft: The group provided linguists, analysts, and cryptologists for RC-135 reconnaissance aircraft, notably the RC-135M 'Rivet Card' and RC-135U 'Combat Apple' missions.
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Vietnam War Contributions: The 6990th played a crucial role in monitoring North Vietnamese communications, providing real-time intelligence to U.S. forces and supporting air operations such as Operation Rolling Thunder.
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“The Front End” and “The Back End”: Members often referred to themselves as “backenders” because they operated in the back of reconnaissance aircraft, analyzing intercepted communications in real time.
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Tragic Loss: On June 13, 1969, a 6990th crew aboard an EC-47 aircraft was shot down over Laos (call sign “Baron 52”), resulting in the loss of the entire crew. Their sacrifice is memorialized among U.S. Air Force intelligence personnel.
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Cold War Operations: The 6990th monitored Soviet, Chinese, and North Korean military communications, contributing to U.S. situational awareness in the Pacific region.
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Awards: The group received multiple Air Force Outstanding Unit Awards for its exceptional performance and contributions to national security.
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Transition: In 1993, the 6990th was inactivated and its legacy continued when its mission and personnel were absorbed into the 390th Intelligence Squadron.
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Legacy: Veterans of the 6990th have formed alumni groups and reunions, preserving the heritage and camaraderie of this unique signals intelligence unit.
