About this Unit
The **551st Airborne Early Warning Group (AEWG)** was an integral unit of the United States Air Force, activated in 1955 at Otis Air Force Base, Massachusetts. Tasked with operating the EC-121 Warning Star aircraft, the group provided airborne radar surveillance and early warning against potential Soviet bomber attacks during the Cold War. The 551st AEWG played a critical role in continental air defense, maintaining round-the-clock patrols over the Atlantic approaches to North America. The unit was inactivated in 1969 as newer technologies and changes in defense strategy rendered its mission obsolete.
Historical Facts
• Origins in World War II: The 551st Airborne Early Warning and Control Wing (AEWG) can trace its lineage to early US Army Air Forces radar and warning units, although the official designation came in the Cold War era.
• Cold War Sentinel: The 551st AEWG was activated at Otis Air Force Base, Massachusetts, in 1955, tasked with operating airborne radar picket aircraft to detect potential Soviet bomber attacks over the Atlantic approaches to North America.
• Home of the "EC-121 Warning Star": The 551st AEWG flew the Lockheed EC-121 Warning Star, a military version of the Super Constellation airliner, outfitted with powerful radar domes and electronic equipment.
• 24/7 Vigilance: At its peak, the 551st AEWG kept multiple EC-121s airborne at all times, patrolling the skies off the East Coast in rotating shifts, contributing to the North American air defense network during the tense years of the Cold War.
• Operation "Big Look": The wing participated in Operation "Big Look," an air defense exercise that tested the US air defense system by simulating Soviet bomber attacks and measuring response times of radar picket and ground-based defenses.
• Cuban Missile Crisis: During the 1962 Cuban Missile Crisis, the 551st AEWG increased its patrols and alert status, playing a crucial role in monitoring the airspace for potential threats from Cuba and the Soviet Union.
• Technological Advancements: The EC-121 aircraft operated by the 551st AEWG were among the first to be equipped with airborne early warning radar and advanced electronic countermeasures, pioneering technology that would evolve into modern AWACS systems.
• Humanitarian Missions: In addition to their defense mission, crews from the 551st AEWG sometimes assisted in maritime search and rescue operations, using their powerful radar to help locate lost ships and aircraft in distress.
• Tragic Loss: On July 11, 1965, an EC-121H of the 551st AEWG crashed into the Atlantic Ocean off Nantucket during a routine mission, resulting in the loss of all 19 crew members. The incident is memorialized at Otis Air Force Base.
• Deactivation and Legacy: With advances in radar technology and the advent of satellites, the need for airborne picket patrols waned. The 551st AEWG was inactivated in December 1969, but its pioneering work laid the foundation for today’s airborne warning and control systems, such as the E-3 Sentry AWACS.
