The AWACS Story

William A. SkillmanWestinghouse Retiree

April 24, 2013

The Need for AWACS1962 – Air Force AEW Pulse Radar (EC-121 Warning Star)

blind to low-flying targets

Pulse Doppler developing technology offered look-downcapability:

Westinghouse: BOMARC, F-4J (F-4 A/C) Single Target radars,

APQ-81-Track-While-Scan (U.S. Navy)

Hughes: F-15

General Electric/Northrop Grumman: E-2, Hawkeye, carrierAEW

1963 USAF TAC & ADC issued

SOR-206 “Airborne Warning and Control System (AWACS)”

AEW = Airborne Early Warning

SOR = Specific Operational Requirement

Response to SOR 206AIRFRAME Proposals:

Boeing, Douglas, LockheedRADAR Proposals:

Westinghouse, Hughes, Raytheon, GE, 3others

AIR FORCE:SAB determined proof of concept needed,ASD formulated Overland Technology

Program(ORT)DOD funded ORT program – 1964

SAB=Air Force Scientific Advisory Board

ASD=AF Aeronautical Systems Division (Wright-Pat)

DOD=Department of Defense

ORT Aircraft – EC121-1966Three Aircraft with scaled radars:

Westinghouse–High PRF (Pulse Repetition Frequency)

Hughes – Medium PRFRaytheon – Low PRFRadar Antenna mounted in lower radome

ORT Antenna in EC-121 Radome

Low sidelobe slotted waveguide array

Results of ORT Flight Tests

1968 Raytheon and GE dropped1968-70 AWACS Support Program to develop

critical radar technologies1970 Boeing selected as “prime” contractor1970 Radar Fly-off initiated: WECO and Hughes

design & build Brassboard radars

Brassboard Fly-off

Dec. 1971- Radars delivered to Boeing - Seattle1972 - Radars installed in 2 Boeing 707sMar.-Sep. 1972 Radar Test Flights

Westinghouse: 49 flights, 300 hoursOct. 1972 Flight test results and DDT& E

proposals resulted in Westinghouse win

Westinghouse Brassboard Radar

AWACS Brassboard AntennaSlotted Waveguide Planar ArrayLow Sidelobes to minimize ground clutterElectronic Steering in Elevation for height finding

Brassboard Aircraft

The Road to Production

Post-Win: Airborne Tracking Demo - 6 flightsVIP flights Andrews AFB

Jan. 1973 Full Scale Production Authorized1974 Jamming Vulnerability “Adequate”1975 Production Radar Flight test begunOct. 1976 1st Prod. Radar delivered to BoeingMar. 1977 1st E-3A, Sentry, delivered to A.F.May 1978 Initial Operational Capability - 6 A/C

1980 Icelandic Odyssey!Balto. > Tinker > Keflavik> England + ReversePurpose: observe performance of improvement

Who has 707 AWACS?U.S.A.F. AN/APY-1

Active: …........................................31

Scrap (TS-3 – BB A/C).................... 1

Crashes (Nellis & Elmendorf AFB)..2

NATO AN/APY-2

Active: …........................................17

Crash (Greece) …............................1

U.K. …..................................................7

France ….............................................4

Saudi Arabia …....................................5

TOTAL..........................................68

Recent AWACS Variants

Boeing 707 out of productionBoeing 767 Japan 4Phased Array – Wedgetail -Boeing 737Australia 6Turkey 4South Korea 4

AWACS Deployments

Saudi Arabia – YemenDesert Storm - IraqAllied Force - KosovoEnduring Freedom - AfganistanIraqi FreedomOdyssey Dawn/Unified Protector - LibyaNoble Eagle – Homeland defenseHumanitarian Relief – Hurricanes Rita & Katrina

Non-US AWACS Radars

These countries are the only exporters, besidesthe U.S., of an AWACS type radar.

Russia IL-76 or A50 or MainstaySweden – SAAB, Ericsson, ErieyeChina – KJ-2000 (mod IL-76)Israel – Israeli Aircraft Industries – Phalcon

Numerous radar/aircraft combinations are beingsupplied to other countries.

ReferencesMuch of the material was drawn from:

“Development of the Airborne Warning and Control System(AWACS) Radar” by Wm. A. Skillman and Robert E. Cowdery,recipients of the IEEE AESS 1995 Pioneer Award for thedevelopment of AWACS. Published in the IEEE Trans. onAerospace and Electronic Systems, Vol 31, No. 4, Oct. 1995.For a later version with color pictures, as well as this slideshow, see the author's website at

“http://SkillmansofAmerica.com”

Link to my home page top right

Here you can also find two eye-witness accounts of theHindenburg disaster of 1937 and a slide show “Rememberingthe Hindenburg” by the author.