• Military Menu                       

• Introduction
• Systems
• Facilities
• Agencies
• Industry
• Operations
• Countries
• Hot Documents
• News
• Reports
• Policy
• Budget
• Congress
• Links

• WMD
• Intelligence
• Homeland Security
• Space

	Director, Operational Test & Evaluation
FY97 Annual Report

E-3 AIRBORNE WARNING AND CONTROL SYSTEM (AWACS)
RADAR SYSTEM IMPROVEMENT PROGRAM (RSIP)

	Air Force ACAT IC Program 33 systems Total program (TY$) $899.8M Average unit cost (TY$) $14.4M Full-rate production 4QFY97 FOT&E 3QFY98 Prime Contractor Boeing Defense And Space Group, Northrop-Grumman Electronic Systems Group

SYSTEM DESCRIPTION & CONTRIBUTION TO JOINT VISION 2010

The Radar System Improvement Program (RSIP) is a joint U.S. and NATO radar hardware and software upgrade for the E-3 Sentry Airborne Warning and Control System (AWACS). RSIP is designed to improve the E-3 radar detection capabilities in both benign and jamming environments and to enhance radar system reliability.

The mission of the E-3 AWACS is to provide land-based theater early warning, air surveillance, fighter control, and air battle superiority. The E-3 AWACS is a commercial Boeing 707-320C airframe modified with a distinctive radome that houses a pulse-Doppler radar capable of detecting aircraft and cruise missiles, particularly at low altitudes. In addition, the E-3 is equipped with general and specialized mission computers, multipurpose displays, and both clear and secure multiple-voice and data link communications. The United States acquired a total of 34 E-3s, one of which is a dedicated test aircraft (Test System 3) operated by Air Force Materiel Command at Boeing Field. One E-3 was lost in an accident. The remaining 32 E-3s are assigned to Air Combat Command. NATO, Great Britain, France, and Saudi Arabia also operate E-3s, each with different configurations than the U.S. aircraft.

The E-3 radar system improvement program will enhance surveillance capability and provide air commanders with improved ability to observe, assess, and control the entire air-battle space, delivering information superiority to the dominant maneuver force as they engage the enemy. First deployed operationally in 1977, the E-3 has become the centerpiece of the theater air control system, performing early warning, air surveillance, combat identification, aircraft monitoring, fighter control, and battle direction missions. The AWACS has been employed in support of joint and multinational operations as part of the overall theater air control system or autonomously in advance of deployment of ground-based command and control systems.

Since initial fielding, the U.S. E-3 AWACS has undergone nearly continuous modification. Early modifications included adding a maritime ship radar detection capability, integrating first generation Class 1 Joint Tactical Information Distribution System (JTIDS) data link terminals, and increasing the operator displays from 9 to 14 to support considerably broadened mission tasks and workload. A significant number of modifications update mission systems, subsystems, flight controls, and navigation software, and replace selective hardware components with more reliable parts. Block 30/35, the most recent system upgrade, adds a 360-degree-coverage passive Electronic Support Measures (ESM) system to support detection and identification, adds a Global Positioning System navigation capability, replaces the Class 1 JTIDS terminal with a Class 2H (High-Power Amplifier, modified) terminal, and adds memory capacity to the central mission computer to support ESM and JTIDS.

As the modification program currently on DOT&E oversight, RSIP replaces the aging AWACS radar subsystem computer, the Airborne Radar Technician workstation, other selected radar system hardware, and radar subsystem software to improve pulse-Doppler radar sensitivity and resistance to electronic counter measures; and it increases reliability and maintainability of the modified components. The RSIP modification to increase the E-3's radar sensitivity, including the development of new waveform and processing algorithms, is planned to restore target-tracking standoff ranges delivered in 1977 that were diluted by the reduction in radar cross-section signatures of fighters and airborne cruise missiles. Improved E-3 reliability and availability are increasingly important as theater commanders continue to rely heavily on the E-3's surveillance and control capabilities to provide the information superiority required to control the battle-space.

The U.S. RSIP IOT&E started with its first sortie on August 3, 1995; but it was suspended almost immediately when a mishap damaged the radar components. Initial findings indicated that although the failure was caused by a non-RSIP component, redesigned RSIP radar subsystem software had improperly overridden safeguards. The radar was repaired, the software was modified, and IOT&E was resumed with the first sortie successfully completed on October 12, 1995. The scheduled six-sortie IOT&E was again suspended because of serious performance deficiencies observed during the IOT&E. The IOT&E resumed for the third time in August 1996; and it was completed in October 1996. RSIP met operational performance requirements at that time. However, suitability issues remained. Data from the U.S. IOT&E was augmented by system performance data gathered during the NATO testing in 1995 and 1996.

After the conclusion of IOT&E, the Air Force developed a post-IOT&E action plan to correct the suitability deficiencies highlighted by IOT&E. The plan consisted primarily of software improvements, but also included some hardware improvements. DOT&E monitored the testing of those improvements and analyzed the data. Post-IOT&E results verified significant improvements in RSIP suitability.

DOT&E has also been monitoring the FOT&E planning. IOT&E involved testing the RSIP-modified AN/APY-2 radars found in the TS-3 test aircraft and one-third of the UASF operational fleet. FOT&E will include the first testing of an RSIP-modified AN/APY-1 radar system. Two-thirds of the U.S. fleet are equipped with the AN/APY-1 radar. RSIP FOT&E will provide the opportunity to test a complete production-representative ESM system with RSIP.

DOT&E analyzed the data from both U.S. and NATO IOT&Es, and also from combined developmental and operational testing. This included post-IOT&E testing. Testing confirmed that the RSIP-modified radar is capable of meeting the current system-level performance requirements and is substantially more effective than the pre-RSIP radar it is intended to upgrade. RSIP is capable of tracking smaller radar cross-section targets at longer range than its predecessor. RSIP is also far more effective when operating against electronic counter measures.

The RSIP-modified radar provides significant improvements in several areas of suitability. The improvements in man-machine interface are a quantum leap forward from the previous system. Additionally, in-flight repair time, diagnostic effectiveness, fault detection, fault isolation, and built-in test (BIT) cannot-duplicate rates are all system successes. Significantly, there have been no critical failures of RSIP hardware in 923 hours of flight testing. However, the issue of software maturity plagued RSIP throughout testing. This is most evident in mean time between failure and mean time between critical failure rates, both of which fell well short of system goals. Despite this, the RSIP-only component break rate met requirements, and the overall radar break rate is comparable to the fleet break rate for 1996.

The only negative affect on current systems capabilities was to the beyond-the-horizon (BTH) radar mode. While this degraded the ability of the U.S. crews to effectively use the BTH mode, NATO crews saw no difference. The cause of the change has been isolated to software. A corrective action plan is being developed to retune all BTH operating modes.

The RSIP-modified radar under test was an AN/APY-2 radar used by one-third of U.S. E-3s. The remainder of the fleet uses the AN-APY-1 radar. The first operational E-3 RSIP upgrade to an E-3B aircraft equipped with an AN/APY-1 radar is ongoing. Therefore, FOT&E will not begin until 3QFY99.

The Air Force approved full-rate production decision in September 1997. NATO and the United Kingdom have already approved RSIP full-rate production for their E-3 fleets.