Origins
The Joint Surveillance Target Attack Radar System (Joint STARS or JSTARS), is a powerful airborne surveillance and target aquisition system providing real-time battle management to field commanders.
The Joint STARS program began as the result of the consolidation of separate US Army and USAF Moving Target Indicator (MTI) programs. The Air Force was pursuing a system known as Pave Mover that provided MTI and SAR surveillance, and included a weapons guidance mode that could guide tactical aircraft or missiles to targets. 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 Pentagon combined SOTAS and Pave Mover into a joint program. The Air Force’s Electronic Systems Division (ESD), based as Hanscom AFB, was designated as the lead service for the program.
From 1982-1984, the Army, Air Force, OSD and Congress thrashed out the requirements for the joint program, as well as the appropriate platform for the sensor. At the time, one option under active consideration was a two-phased program in which the radar would initially be deployed on ten conventional aircraft, with subsequent production focused on a stealth platform derived from the TACIT BLUE test aircraft. 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 and include both MTI, SAR, and weapons guidance capabilities. On September 27th 1985 the Full Scale Development contract worth $5 billion was awarded to Grumman Aerospace Company, with the radar development portion being subcontracted to Norden Systems. The contract included the production of two development Joint STARS aircraft with a plan for 10 production aircraft, and support for developmental testing and a European field test demonstration.
In April 1988, Grumman completed the construction of the first E-8A prototype (86-0416/N770JS), and carried out 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 on December 22nd 1988. The second E-8A (86-0417/N8411) made its first flight on August 31st 1989. In the same month the first J-STARS instantaneous communication to a ground station was completed. In 1989 the two E-8As made three visits to Europe for trials.
Also in April 1988 the Defense Acquisition Board made major changes to the program. It increased the number of E-8 aircraft to be built to 22 from the 10 originally planned, and approved a plan to use new Boeing 707 aircraft instead of used 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 towards the new-build option. By late 1989, however, the cost of newly built E-8B airframes jumped because the 707 production line was due to close in May 1991. This led to the decision in November 1989 to build the E-8C on used 707 airframes. The sole new-build 707 which had been procured was exchanged for five used 707s from Omega Air.
After the Gulf War in 1991, during which the two E-8A aircraft had flown 49 combat missions, the Senate pushed to accelerate the production schedule of Joint STARS. The SASC wanted to authorize the production of six aircraft by 1994 (the Air Force plan was for three aircraft by 1994). The Air Force felt that the effort in the Gulf War had not alleviated the need for operational testing and further enhancements, but rather illuminated areas that needed more attention in development. One problem was that the E-8As were not in production configuration. In November 1990, the Air Force had awarded a follow-on full scale development contract for a third developmental aircraft in the full production configuration. This configuration included system enhancements that the two aircraft deployed to the Gulf did not have. Finally, approval for low-rate production of five E-8C aircraft was granted in 1993. This decision was supported by developmental testing of the aircraft, called the System Level Performance Verification (SLPV).
The Joint STARS aircraft was scheduled to begin its initial operational test and evaluation in November 1995. That testing was delayed and then changed because two aircraft were deployed to the European theater to support Operation Joint Endeavor in Bosnia. The Air Force Operational Test and Evaluation Center (AFOTEC) and the U.S. Army Operational Test and Evaluation Command conducted a combined development and operational test of Joint STARS from July through September 1995 and an operational evaluation of the system during Operation Joint Endeavor from January through March 1996. Crews flew 95 consecutive operational sorties and more than 1,000 flight hours with a 98 percent mission effectiveness rate.
Joint STARS returned to support Operation Joint Endeavor II in October 1996 when the first production E-8C from the 93rd Air Control Wing and a testbed E-8C from Northrop Grumman Corp. deployed to Germany. Crews flew 36 operational sorties in November and December for more than 470 flight hours. The second production aircraft joined the first after it was delivered to the Air Force in December.
On September 25th 1996 the Under Secretary of Defense for Acquisition and Technology signed an acquisition decision memorandum approving the Joint STARS program's entry into full-rate production with a total planned quantity of 19 aircraft. But despite the JSTAR's performance during its combined development and operational test, and during the operational evaluation done in Bosnia, this did not support a decision to commit the system to full-rate production because the system had not met its overall suitability requirements during Operation Joint Endeavor.
The main problems were that the engines were not powerful enough to allow the E-8C to operate at 40000 feet where radar performance is significantly improved; indeed, with a full fuel load only 32000 feet can be achieved, and 11000 feet of runway is needed for take-off. Secondly, tactics, techniques, and procedures to integrate Joint STARS into operational theaters had not been developed. Thirdly, during Operation Joint Endeavor, Joint STARS did not achieve the time-on-station requirement (but this was an impossible task with only two aircraft available).
In May 1997 the Quadrennial Defense Review directed that the planned buy of 19 production aircraft be reduced to 13, contingent on NATO buying 6 Joint STARS aircraft. However, in October 2002 funding was provided for a seventeenth aircraft.
Although not publicised, the JSTARS system was one of the greatest air power triumphs of Operation Iraqi Freedom in March/April 2003.
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