As the final E-2C Hawkeye 2000 proceeds down the Northrop Grumman production line at St. Augustine, Florida, the company is preparing to fly the first example of its replacement–the E-2D Advanced Hawkeye. The first of two system development and demonstration (SDD) aircraft was rolled out at the plant on April 30 and is being checked out on the ground prior to a first flight in late summer. It will serve primarily as an aircraft systems testbed. The second SDD aircraft, for mission system testing, will follow close behind.

Advanced Hawkeye represents a thorough overhaul of the tried and trusted E-2 design. As Jerry Spruill, NG Integrated System’s director and IPT leader of AEW International Programs, neatly summed it up, “It casts the same shadow on the ramp, but inside it’s totally different.” The Hawkeye has undergone a series of improvements throughout its 40-year history, the latest in-service iteration being the Hawkeye 2000. While the E-2D draws on this experience, the extent of the changes being implemented dictated a change in designation.

At the E-2D’s heart is the Lockheed Martin APY-9 radar system with an ADS-18 antenna. This rotates, as did previous Hawkeye radars, but is an electronically scanned phased array, allowing great versatility in beam-shaping and direction. Capt. Tom Carroll, from the Naval Air Systems Command at Patuxent River, explained, “The advantages of a rotating antenna is that it doesn’t matter which way the aircraft is pointing to get optimum performance. Trying to position the aircraft correctly for the radar may not always be possible, depending on the scenario. By using electronic steering as well, we have much greater versatility. For instance, we can use the electronic scanning to dwell on a target while the antenna is physically rotating, something that you can’t do with a conventional radar.”

The E-2’s system is based on open-architecture, commercially based components, resulting in a flexible system that can be rapidly fielded, easily tailored to differing requirements and easily upgraded with new technology insertion. As well as the radar, the E-2D has a comprehensive passive ESM system with high-gain antennas and a communications suite that allows it to act as a key node in the netcentric environment. To cope with the extra weight of the new equipment, the E-2D has uprated Rolls-Royce T56-A-427A engines.

In the cabin the system operators have 20.1-inch color displays at each workstation, but it is “up front” where the Hawkeye crew will notice the main difference. The E-2D has a completely new glass cockpit, based on three 17-inch color displays–one in front of each pilot and one between them. While both pilots are fully occupied during takeoff and approach, experience has shown that only one pilot is needed to fly the aircraft once it reaches its operational area. Consequently, the E-2D is configured so that the copilot can use his or her display as a tactical screen and act as a fourth mission system operator.

Following the two SSD aircraft will be three pilot production aircraft, followed by low-rate initial production. Elements of the mission system, including a proof-of-concept radar antenna, are being tested at Patuxent River using a rotodome-equipped NC-130 Hercules. Initial operational clearance for the U.S. Navy is planned for 2011, and Northrop Grumman expects to build 75, including the trials machines. Exportability issues concerning the APY-9 and other systems are currently being reviewed, although the UAE has shown considerable interest and has issued a request for information. India and Malaysia are also export prospects.