The E-8C Joint Surveillance Target Attack Radar System (Joint STARS) is a
long-range, air-to-ground surveillance system designed to locate, classify and track ground targets in
all weather conditions. As an airborne battle management and command and control platform, it
conducts ground surveillance to develop an understanding of the enemy's situation and to support
attack operations and targeting that contributes to the delay, disruption and destruction of enemy
While flying in friendly airspace, the joint Army-Air Force program can look deep
behind hostile borders to detect and track ground movements in both forward and rear areas. It has a
range of more than 150 miles (250km). These capabilities make "Joint STARS" effective for dealing
with any contingency, whether actual or impending military aggression, international treaty
verification, or border violation.
"Joint STARS" evolved from U.S. Air Force and Army programs to develop, detect,
locate and attack enemy armor at ranges beyond the forward area of troops. The Air Force was
pursuing a system known as Pave Mover that provided moving target indicator (MTI) and
synthetic aperture radar (SAR) surveillance, and included a weapons guidance mode that could guide
tactical aircraft or missiles to targets. The Pave Mover program was preparing to enter full
scale development before the consolidation. The Army had built a system called SOTAS, a
helicopter-based, MTI-only system that had run into cost and technical problems during full scale development.
In 1982, the programs were consolidated and the Air Force became the lead agent. In May
1984, the Chiefs of Staff of the Air Force and Army made the final decision to put the "Joint STARS"
radar on a Boeing 707 platform. In September 1985, the Full Scale Development contract for the system
was awarded to Grumman Aerospace Company, with the radar development portion being subcontracted to
Norden Systems. The contract included the production of two developmental "Joint STARS" aircraft with
a plan for 10 production aircraft, and support for developmental testing and a European Field Test
In April 1988, Grumman was able to put together an E-8A "Joint STARS" prototype on
the first rebuilt Boeing 707 and complete a test flight without the radar sensor. The Norden radar
was later integrated onto the airplane, and the first full test flight using the radar occurred in
December. Also in April 1988, the Defense Acquisition Board made major program changes. It increased
the number of E-8 aircraft to be built to 22 from the 10 originally planned, and approved a program
plan to use new Boeing 707 (E-8B) aircraft instead of used (E-8A) platforms. The first two E-8A
development airplanes were 20-year-old commercial Boeing 707s, whose conversion difficulties and
questions of remaining service life pushed the board toward having subsequent aircraft be E-8B
airframes. By late 1989, however, the cost of newly built E-8B airframes jumped because of a
production gap between the last 707-based aircraft in 1991 and what would be the first production
version "Joint STARS" two to three years later.
In November 1989, the Pentagon approved the re-baseline of the program to use
older 707 airframes in the E-8C configuration. The program office had examined other platform
options, including Boeing's 757 and 767 and the McDonnell Douglas MD-11, but these were all cost
prohibitive and the change in configuration would have jeopardized the initial operational
capability date of 1997.
The E-8A pre-production model was owned exclusively by Northrop Grumman Corp.
Although still under development, two aircraft deployed in 1991 to participate in Desert Storm. The
joint program accurately tracked mobile Iraqi forces, including tanks and Scud missiles. Crews flew
developmental aircraft on 49 combat sorties accumulating more than 500 combat hours and a 100 percent
mission effectiveness rate.
"Joint STARS" developmental aircraft were also called to support the NATO
peacekeeping mission, Operation Joint Endeavor, in December 1995. While flying in friendly air
space, the testbed E-8A and pre-production E-8C aircraft monitored ground movements according to the
Dayton Peace Treaty agreements. Crews flew 95 consecutive operational sorties and more than 1,000
flight hours with a 98 percent mission effectiveness rate.
The E-8C is the production model owned by the Air Force. It first flew in March
1994 and was delivered in June 1996. A second aircraft followed in December 1996. The two
E-8A testbed aircraft will be upgraded to C-model standard and will be the last to be delivered.
"Joint STARS" returned to Operation Joint Endeavor when the 93rd Air Control Wing
(ACW) deployed in October 1996. The first production E-8C and a pre-production E-8C from Northrop
Grumman Corp. flew 36 operational sorties and more than 470 flight hours with a 100 percent
effectiveness rate. The wing declared initial operational capability on 18 December 1997. A fourth
production aircraft, designated backup aircraft inventory, was delivered to the Air Force on 18
The E-8C is a modified Boeing 707-300 series commercial airframe extensively
enhanced with the radar, communications, operations and control subsystems required to perform its
operational mission. The most prominent external feature is the 40-foot (12m) long, canoe-shaped
radome under the forward fuselage that houses the 24-foot (7.3m) long, side-looking phase array
The E-8C can respond quickly and effectively to support worldwide military
contingency operations. It is a jam-resistant system capable of operating while experiencing heavy
electronic countermeasures. The aircraft can fly a mission profile for more than eight hours without
refueling, although its range and on-station time can be increased through inflight refueling.
The radar and computer subsystems on the E-8C can gather and display broad and
detailed battlefield information. Data is collected as events occur. This includes position and
tracking information on enemy and friendly ground forces. The information is relayed in near-real
time to the Army's common ground stations via the secure jam-resistant surveillance and control data
link and to other ground command, control, communications, computers and intelligence nodes beyond
line-of-sight via ultra high frequency (UHF) satellite communications.
Radar operating modes include wide area surveillance, MTI, sector search MTI, and
SAR. The antenna can be slued to either side of the aircraft to provide a 120-degree field of view
covering nearly 19,305 square miles (50,000 sq km) and is capable of detecting targets at ranges from
164,049 to 820,248 feet (50-250km) from the aircraft. In addition to being able to detect, locate and
track large numbers of ground vehicles the radar has some limited capability to detect helicopters,
rotating antennas and low slow-moving fixed-wing aircraft.
Other major E-8C subsystems are communications, operations and control. Eighteen
operator workstations display computer-processed data in graphic and tabular format on video
screens. Operators and technicians perform battle management, surveillance, weapons, intelligence,
communications and maintenance functions.
In support of air-to-ground operations, the E-8C can provide the direct
information needed to increase situation awareness with intelligence support and support attack and
targeting operations to include attack aviation, naval surface fire, field artillery and friendly
maneuver forces. It also provides information for air and land commanders to gain and maintain
control of the battle-space and execute against enemy forces.
Wide Area Surveillance and Moving Target Indicator (WAS/MTI) are the radar's
fundamental operating modes. WAS/MTI is designed to detect, locate and identify slow-moving targets.
Through advanced signal processing, "Joint STARS" can differentiate between wheeled and tracked
vehicles. By focusing on smaller terrain areas, the radar image can be enhanced for increased
resolution display. This high resolution is used to define moving targets and provide combat units
with accurate information for attack planning.
Synthetic Aperture Radar/Fixed Target Indicator (SAR/FTI) produces a
photographic-like image or map of selected geographic regions. SAR data maps contain precise
locations of critical non-moving targets such as bridges, harbors, airports, buildings, or stopped
The FTI display is available while operating in the SAR mode to identify and
locate fixed targets within the SAR area. The SAR and FTI capability used in conjunction with MTI
and MTI history display allows post-attack assessments to be made by onboard or ground operators
following a weapon attack on hostile targets.
"Joint STARS" operates in virtually any weather, on-line, in real-time, around the
clock. The augmented Air Force/Army mission crew can be deployed to a potential trouble spot within
hours and provide valuable data on ground force movements.
On a standard mission the aircraft has a crew of 21, with three flight crew and 19
systems operators. On a long endurance mission the aircraft has a crew of 34, with 6 flight crew and
28 system operators.
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