E-3 Sentry (AWACS) Block 30/35

The AWACS Block 30/35 Modification was an in-progress production and installation program that was the E-3 fleet's largest upgrade, completed in 2001. Development of the Block 30/35 upgrade began in May 1987 and the first aircraft was completed in October 1995. The last of 32 US E-3s rolled out of production 20 October 2001, with the final Block 30/35 modification installed and thrust into operational service by the 552nd Air Control Wing at Tinker AFB. The Block 30/35 Modification Program upgrade, distinguished by the 'cheek' bulges just behind the cockpit, includes four enhancements to add ESM, JTIDS, GPS Integrated Navigation, and additional computer processing power to the E-3.

The Joint Tactical Information Distribution System provides secure, anti-jam communication for information distribution, position location and identification capabilities. An increase in the memory capability in the computer accommodates JTIDS, EMS and future enhancements. The Class 2H JTIDS terminal is a secure digital communications system that allows E-3 crew members to communicate with other participants in air battle, such as fighter aircraft, Navy units and ground-based units. It has a capability to identify units using common points of reference. The new Link 16 radio improved the latency eight-fold. Latency of the AWACS picture will be reduced from 40 seconds to 5 seconds. The Global Positioning System satellite-based positioning capability provides precise global navigation. The GPS enhancements incorporates the system into navigation and mission crew computers, which lets crews to more accurately determine the position of the E-3 and the weapons system it is tracking. It also enhances flight planning. Major advantages include 200 times more accurate locations of targets passed via JTIDS (Link 16) and/or Link 11. GPS timing via 1553 bus synchronizes sensors, communications, and processors to common reference.

The AWACS Combat ID /IFF program includes: (1) the IFF Top Priority program second part, Block 30/35 APX-103B, including scan-to-scan processing for code de-garble improvement, and obtaining aircraft attitude and altitude data via GINS 1553 Bus and (2) replacing the current IFF Transmitter with a new Solid State IFF Transmitter that corrects R,M,&A problems and provides Mode S compatibility. The SS IFF Transmitter is an Extend Sentry "#1 Must Do" item. Classified Combat ID may be POMed via this program but have zero required funding at this time. The IFF Top Priority was in an installation phase by FY00. The SS IFF Transmitter was acquired as a NATO and US AWACS coordinated (no MOA) Project. NATO funded the R&D effort in FY00 but took a slightly different approach to IFF improvements so minor US design changes may be necessary.

The AWACS Computer & Display Modernization replaced the E-3's "steam driven computer" and is the highest ranked major project in the Extend Sentry priority list. Step 1 installation began in the fall of 1998 with 1/3 of fleet complete at start of FY00 FYDP in an effort coordinated with NATO. The migration of the E-3 processing system to open system Defense Information Infrastructure Common Operating Environment (DII COE) compliance is as important to the AWACS mission as the RSIP sensor upgrade. The modernization of US AWACS mission computing capability is evolutionary. The goal was to inject crucial technological improvements in two steps. This approach was used primarily due to funding constraints and the desire to get critical mission capabilities into the hands of the warfighter as soon as possible. The key components delivered to the user in Step 1 included a better target tracker algorithm, more detailed and useful maps, increased use of colors (allowing more and different symbols to be displayed), and an overall improved Human-Computer Interface (HCI) leading to better situational awareness. ATO processing, battle management decision aids, intel data overlays, weather overlays, and other critical software were adapted from DII COE applications and delivered after the hardware and basic capability is in place. Step 2 of the AWACS mission computing upgrade provided the warfighter with a completely open DII COE compliant computing architecture enabling rapid, low cost delivery of plug and play capability. It involved the removal of the CC-2E computer and the Airborne Operational Computer Program (AOCP) mission software and full migration to DII COE compliance.

The AWACS ESM Upgrades includes 4 sub-projects: (1) RF Front End Redesign to remove local oscillator leakage, increase producibility / maintainability, and remove current frequency management for cosite interference (Dem/Val flight in 4Q98/1Q99); (2) Specific Emitter ID provides ability for ESM ID to emitter serial number -key to Blue/Gray and increases correlation to tracks at higher rates than available from primary sensors; (3) Side Lobe Detection Enhancement increases the sensitivity beyond current capabilities such that emitters can be detected without the E-3 in the emitter's main beam; and (4) Multiple Platform Geolocation uses the ESM system to passively obtain very rapid and accurate geolocation of emitters. Electronic Support Measures provide for a passive detectionelectronic surveillance capability to detect and identify air and surface-based emitters. The ESM system passively detects signals from hostile, neutral, friendly, and unknown emitters and identifies targets, augmenting present on-board sensors. This system greatly improved the E-3 combat identification, surveillance and weapon control capability.