SOR, responded. In July 1966, Boeing and
Douglas received contracts for advanced
concept formulation studies.
General Electric, Raytheon, Hughes
Aircraft and Westinghouse each received
similar contracts for the radar – for which,
in 1967, Westinghouse and Hughes were
selected to compete – and the Department
of Defense formally approved the AWACS
Program in December 1968. Responsibility
for development was assigned to the Air Force
Systems Command’s Electronic Systems
Division at Hanscom AFB, Massachusetts.
Boeing and McDonnell Douglas (created
through the 1967 merger of McDonnell
Aircraft and Douglas Aircraft) responded
to a nal RFP in December 1968, offering
variants of the 707-320 and DC-8-62 airliners
respectively – with Boeing chosen in July
1970 as the prime contractor and AWACS
systems integrator.
The company received a contract to
modify two 707-320 airframes to support the
evaluation of competing radars under the
‘Brassboard Flyoff’ assessment.
The rst of two prototypes took its
maiden ight under the designation EC-
137D on February 6, 1972, and testing of
the trial radars followed from March 14 toAugust 31, 1972. As the integrator, Boeing
selected the Westinghouse (now Northrop
Grumman) system, which received the
designation AN/APY-1.
Design, development, test and evaluation
formally began in October 1972 and approval
to begin full-scale work-up followed on
January 19, 1973. Although the USAF’s initial
requirements included 64 production aircraft,
by 1973 the number had been cut to 34.FIRST FLIGHT
Four test aircraft clocked up around 1,800 hours
and 451 ights during a 16-month evaluation
that concluded before the rst production
aircraft conducted its maiden air test under the
designation E-3A on October 31, 1975.
Westinghouse delivered the rst
production radar in October 1976 and the
Tactical Air Command’s 552nd Airborne
Warning and Control Wing (AWACW), from
October 1991 it became the 552nd Air Control
Wing, at Tinker AFB, Oklahoma, received its
rst E-3A, 75-0557, on March 23, 1977.
The wing’s rst mission followed a
week later and the E-3A achieved initial
operational capability (IOC) on April 16,
1978 – with the name Sentry assigned to the
type a month later.The E-3A’s rst USAF tasking began in
September 1978 when the 963rd Airborne
Warning and Control Squadron (AWACS)
deployed to Kadena Air Base, Japan.
Whereas the initial 25 ‘Core’ E-3As
featured the AN/APY-1 radar, the 26th and
subsequent aircraft were equipped with the
upgraded AN/APY-2 system – development
of which started in December 1976 and ight
testing in June 1979.
Delivered from December 10, 1981, the
APY-2-equipped ‘Standard’ aircraft featured
a maritime surveillance mode capable of
detecting large and small surface ships. In
addition to the USAF jets, Boeing delivered
18 Standard E-3As to NATO from January- The rst production E-3A (serial 73-
- was also converted to the Standard
con guration and served as a dedicated test
bed.
The Sentry achieved full operational
capability with the delivery of the last of the
34 USAF jets in June 1984. They included
both EC-137Ds, which were brought up to
Core E-3A con guration.
The E-3’s most eye-catching feature is
its 30ft-diameter (9.1m) rotating dome, or
rotodome. Mounted on struts above the aft
fuselage, it houses antennas for the radar
http://www.aviation-news.co.uk 63The ‘ZZ’ tail code on E-3B 71-1408 shows
it’s allocated to the 18th Wing at Kadena
AB, Okinawa, Japan. This was the second
development aircraft, own under the EC-
137D destination. Jim Haseltine62-67_e3sDC.mfDC.mfDC.indd 63 02/03/2018 17:53