Boeing E-3A Sentry
With the piston-engined Lockheed EC-121 Warning Stars in USAF service beginning to show their age, the USAF issued a dual requirement in 1966 for a jet-powered airborne early warning system and an advanced radar to go with it. Both Boeing and McDonnell Douglas submitted designs based on their successful airliners—the 707 and the DC-8 respectively—while Hughes and Westinghouse competed for the radar. Because the USAF was familiar with the 707 series thanks to its use of the C-137 Stratoliner and KC-135 Stratotanker, the Boeing proposal was chosen, with two aircraft designated as pre-production EC-137D testbeds.
The radar was more problematic, as both companies had submitted superb designs, but eventually Westinghouse won the competition due to its use, revolutionary at the time, of digital programmable battle computers. Though the 30-foot diameter rotating radar dome looked a little incongruous mounted atop the fuselage, it was no detriment to performance and was a huge improvement over that carried by the EC-121; it combined the two radars of the Warning Star into one single piece of equipment and had much better look-down capability as compared to the earlier aircraft. The interior of the aircraft was fitted with control stations, giving the USAF unmatched battle airspace management capability, thanks to datalinks that connected the E-3 into integrated systems already in place, namely in NATO Central Europe.
The APY-1 radar can detect aircraft out to 400 miles, which encompassed most of the European continental airspace, as well as provide some overwater detection capabilities. The range and loiter capability of the E-3 allowed it to remain well behind the battle line for hours on circular “tracks”; while the E-3 would be a prized target during a war, it would be difficult to get to (though the Soviet Union developed the MiG-31 Foxhound partially to eliminate NATO Sentries in time of war).
After an uneventful testing period with the EC-137Ds, the aircraft was placed in full production as the E-3A Sentry AWACS (Airborne Warning and Control System) in 1975, with the first aircraft entering service in 1977. Throughout the Cold War, USAF E-3s—soon joined by 18 Sentries built specifically for NATO use, based in Germany with Luxembourgian registration—maintained steady patrols from Iceland to Turkey, keeping electronic eyes on Warsaw Pact forces behind the Iron Curtain. The greatest achievement that can be given to these aircraft is probably that their mere presence may have acted as a deterrent, as an all-out surprise attack on NATO bases would have been detected early.
The first combat use of the E-3 would come in 1991, during the First Gulf War with Iraq. USAF and Saudi Arabian E-3s were among the first aircraft to arrive for the buildup to war in Operation Desert Shield, and these aircraft continually kept an eye on Iraqi deployments throughout the six-month prelude to war. This was to come in handy when hostilities began, as the E-3 crews could anticipate Iraqi reactions and vector fighters, mainly F-15 Eagles, to intercept Iraqi fighters before a strike force was threatened. Of the 41 confirmed kills made by Coalition forces in Desert Storm, 38 were done with the assistance of E-3 crews. The performance of the Sentry made an impression on air forces around the world, resulting in France buying E-3Fs; the United Kingdom had already placed an order for Sentry AEW.2s to replace both the ancient Shackleton AEW.2s in service and the failed Nimrod AEW.1.
While the E-3 had proven itself over Iraq, its electronics were getting dated: by 1995, personal computers had more storage space than the E-3’s 1977-technology machines. This was rectified in a long upgrade program that upgraded all of the Sentry’s electronic systems, as well as giving it enhanced surveillance capability by adding ESM sensors in bulges along the fuselage sides and underneath the nose: besides being able to vector fighters to airborne intercepts and coordinate airstrikes on ground targets, upgraded E-3Cs can now also detect enemy radars and send Wild Weasel SEAD aircraft against them. The newest upgrade, completed in 2001, added GPS to the E-3’s capability. The USAF is currently considering re-engining the E-3 fleet with more fuel efficient high-bypass turbofans, already done in the RAF, French, Saudi, and NATO Sentries. Of the 68 E-3s built or converted, 65 remain in service, three having been lost in accidents.
Dad took this picture of a 552nd AWCW E-3A shortly after it arrived on a rainy morning at Ramstein AB in 1978. This was one of the first deployments of an AWACS to Europe, and Dad was soon to take off in it--his job when we were in Germany was the early version of what is today called battlespace management. As such, the people in his career field needed to learn how to integrate the E-3 into that concept. Not only did Dad get to fly in the AWACS, he actually got to fly it...but that's a story for another day.
I'm not sure of the tail number on this particular E-3, but as far as I know, it is still in USAF service.
Boeing E-3A Sentry
With the piston-engined Lockheed EC-121 Warning Stars in USAF service beginning to show their age, the USAF issued a dual requirement in 1966 for a jet-powered airborne early warning system and an advanced radar to go with it. Both Boeing and McDonnell Douglas submitted designs based on their successful airliners—the 707 and the DC-8 respectively—while Hughes and Westinghouse competed for the radar. Because the USAF was familiar with the 707 series thanks to its use of the C-137 Stratoliner and KC-135 Stratotanker, the Boeing proposal was chosen, with two aircraft designated as pre-production EC-137D testbeds.
The radar was more problematic, as both companies had submitted superb designs, but eventually Westinghouse won the competition due to its use, revolutionary at the time, of digital programmable battle computers. Though the 30-foot diameter rotating radar dome looked a little incongruous mounted atop the fuselage, it was no detriment to performance and was a huge improvement over that carried by the EC-121; it combined the two radars of the Warning Star into one single piece of equipment and had much better look-down capability as compared to the earlier aircraft. The interior of the aircraft was fitted with control stations, giving the USAF unmatched battle airspace management capability, thanks to datalinks that connected the E-3 into integrated systems already in place, namely in NATO Central Europe.
The APY-1 radar can detect aircraft out to 400 miles, which encompassed most of the European continental airspace, as well as provide some overwater detection capabilities. The range and loiter capability of the E-3 allowed it to remain well behind the battle line for hours on circular “tracks”; while the E-3 would be a prized target during a war, it would be difficult to get to (though the Soviet Union developed the MiG-31 Foxhound partially to eliminate NATO Sentries in time of war).
After an uneventful testing period with the EC-137Ds, the aircraft was placed in full production as the E-3A Sentry AWACS (Airborne Warning and Control System) in 1975, with the first aircraft entering service in 1977. Throughout the Cold War, USAF E-3s—soon joined by 18 Sentries built specifically for NATO use, based in Germany with Luxembourgian registration—maintained steady patrols from Iceland to Turkey, keeping electronic eyes on Warsaw Pact forces behind the Iron Curtain. The greatest achievement that can be given to these aircraft is probably that their mere presence may have acted as a deterrent, as an all-out surprise attack on NATO bases would have been detected early.
The first combat use of the E-3 would come in 1991, during the First Gulf War with Iraq. USAF and Saudi Arabian E-3s were among the first aircraft to arrive for the buildup to war in Operation Desert Shield, and these aircraft continually kept an eye on Iraqi deployments throughout the six-month prelude to war. This was to come in handy when hostilities began, as the E-3 crews could anticipate Iraqi reactions and vector fighters, mainly F-15 Eagles, to intercept Iraqi fighters before a strike force was threatened. Of the 41 confirmed kills made by Coalition forces in Desert Storm, 38 were done with the assistance of E-3 crews. The performance of the Sentry made an impression on air forces around the world, resulting in France buying E-3Fs; the United Kingdom had already placed an order for Sentry AEW.2s to replace both the ancient Shackleton AEW.2s in service and the failed Nimrod AEW.1.
While the E-3 had proven itself over Iraq, its electronics were getting dated: by 1995, personal computers had more storage space than the E-3’s 1977-technology machines. This was rectified in a long upgrade program that upgraded all of the Sentry’s electronic systems, as well as giving it enhanced surveillance capability by adding ESM sensors in bulges along the fuselage sides and underneath the nose: besides being able to vector fighters to airborne intercepts and coordinate airstrikes on ground targets, upgraded E-3Cs can now also detect enemy radars and send Wild Weasel SEAD aircraft against them. The newest upgrade, completed in 2001, added GPS to the E-3’s capability. The USAF is currently considering re-engining the E-3 fleet with more fuel efficient high-bypass turbofans, already done in the RAF, French, Saudi, and NATO Sentries. Of the 68 E-3s built or converted, 65 remain in service, three having been lost in accidents.
Dad took this picture of a 552nd AWCW E-3A shortly after it arrived on a rainy morning at Ramstein AB in 1978. This was one of the first deployments of an AWACS to Europe, and Dad was soon to take off in it--his job when we were in Germany was the early version of what is today called battlespace management. As such, the people in his career field needed to learn how to integrate the E-3 into that concept. Not only did Dad get to fly in the AWACS, he actually got to fly it...but that's a story for another day.
I'm not sure of the tail number on this particular E-3, but as far as I know, it is still in USAF service.