Lockheed Ec-121 Constellation

Quad Piston

The Lockheed EC-121 Warning Star represents the military evolution of one of aviation's most elegant designs — the triple-tailed Constellation. Developed in the 1950s from the civilian Super Constellation, the EC-121 served as the U.S. military's primary airborne early warning and control platform throughout the Cold War, bristling with radar domes above and below the fuselage. Powered by four Wright R-3350 Duplex-Cyclone radial engines producing 3,250 horsepower each, these aircraft could remain on station for over 20 hours, patrolling the Atlantic and Pacific approaches to detect Soviet bombers long before ground-based radar could see them. The type flew critical missions during the Vietnam War, directing fighter intercepts and monitoring North Vietnamese air activity from stations over the Gulf of Tonkin and Laos. With a service ceiling around 20,000 feet and cruising speed of 240 knots, the EC-121 was never fast by jet standards, but its endurance and radar capability made it irreplaceable until the E-3 Sentry entered service in the 1970s. Today only a handful remain airworthy, preserved by warbird organizations as flying monuments to the piston-engine era's technological zenith. The distinctive Constellation silhouette — with its graceful dolphin fuselage and signature triple tail — makes every EC-121 appearance at airshows a reminder of when propeller-driven aircraft still ruled military aviation. SkyMeter has tracked flights across airframes and operators, with the largest observed operator.