Cover Story: Hawkeye’s Long Vision

By Ron Laurenzo | October 1, 2007
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Like many in their 40s, the E-2 Hawkeye program has learned a lot over the years, becoming smarter and better at what it does while realizing that time has taken its toll. But unlike other 40-somethings, the U.S. Navy’s flying radar program is undergoing a midlife rejuvenation that will make the second half of its life even better.

Outside, the new E-2D Advanced Hawkeye airborne early warning and command and control aircraft will look the same as its predecessor. But inside, it will feature a revolutionary new radar system combined with powerful digital processing and communications capabilities that essentially knock down the door to 21st century warfare already cracked open by the current E-2C fleet.

Thanks to these new systems, the E-2D will be a better "digital quarterback" than the E-2C, seeing larger amounts of the battle space more clearly, processing more information faster and zipping it to a variety of users in real time for immediate results.

"The capability for ‘digital quarterback’ is kind of there today, but it will become much more capable," said Navy Capt. Randy Mahr, E-2D Hawkeye program manager. "We’re talking about the difference [of] going from a very good college quarterback to Peyton Manning."

Built by Northrop Grumman in St. Augustine, Fla., the E-2D made its first flight in early August, starting a testing program that will end in early 2009. Introduction to the fleet is scheduled for 2011.

A second test aircraft will take off in November and begin airborne testing of Lockheed Martin’s APY-9 radar in December or January. Lab tests of the radar were ongoing in Lockheed Martin’s Syracuse facility as well as Northrop Grumman’s integration lab in Bethpage, N.Y. L-3 Communications Randtron Antenna Systems, Menlo Park, Calif., is building the ADS-18 antenna housed in the aircraft’s signature rotodome.

The hybrid mechanical and electronically scanning APY-9 radar, the result of a Navy study in the 1980s to replace the current radar system, is the primary reason for the Advanced Hawkeye. More powerful and sensitive, the APY-9 has a new digital receiver, power amplifiers and other components. The radar mechanically rotates to cover a full circle around the aircraft. If it spots something of interest, it can stop and stare, concentrating power for a better image without waiting for the sweep of a purely mechanical array.

Operating in the UHF band, the APY-9 will cover 250 percent more volume than its predecessor and, just as importantly, will pick out small targets at long ranges amid the clutter of the littorals — where land and sea meet — and over land. Fitting it all into the same-sized package with an open architecture that will allow it to stay cutting edge for another 30 or 40 years was a significant challenge, said Tom Vice, a vice president with Northrop Grumman’s Integrated Systems sector.

"You’re not talking about an evolutionary step, but almost a revolutionary step," Vice said.

Missile defense

Foremost among current threats are advanced anti-ship cruise missiles, which can be both stealthy and supersonic. They are weapons of choice for nations seeking to keep the U.S. Navy far off their shores.

Detecting them at long range and passing data to fighters or surface ships will permit engagement further away from the fleet with higher chances of success.

Military planners see future conflicts increasingly taking the Navy and Marines into littoral areas, home to a majority of the world’s population and an array of threats not posed during the Cold War.

The Advanced Hawkeye also will be critical to naval ballistic missile defense as well as detecting and defeating conventional threats like enemy attack aircraft. According to the Navy and Northrop Grumman, the Advanced Hawkeye will provide a 200-percent improvement in kills for Aegis missile ships and a 600-percent improvement for F-18s equipped with new Active Electronically Scanned Array (AESA) radar.

"The limitations on E-2C are that we’re essentially an over-water platform, said Mahr. "We’re very good at handling things over water; we have a limited capability over land and in the littorals."

Although the radar garners most of the attention, the E-2D’s computing and communications capabilities are noteworthy. The aircraft will incorporate "publish/subscribe" middleware facilitating distributed computing applications. Despite the complexity, however, software development has not delayed the program.

"This is the first program that I’ve been associated with where software is not driving my schedule," Mahr said.

The Navy and Northrop Grumman have continually upgraded the Hawkeye since it joined the fleet in 1964. The E-2C entered service in 1973, evolving from the "simple threats" of the Cold War to the murkier present, where the Navy patrols a global frontier filled with dangers ranging from the conventional to the very unconventional.

The Navy has 69 E-2C Hawkeyes with five more E-2Cs, four trainers and one Hawkeye 2000 — the latest C variant — in Northrop Grumman’s production pipeline.

The C models, which like all heavily used carrier-borne aircraft suffer from corrosion and other aging issues, are scheduled to retire by 2020. The service intends to procure 75 D models. Another 35 E-2Cs are flying with Mexico, France, Egypt, Japan, Taiwan and Singapore, providing a potential export market for the new version.

Despite the age of the design, the Navy concluded the E-2 was still the best choice for the job after conducting studies in the 1990s. The Navy’s venerable land-based patrol aircraft, the P-3 Orion, is being replaced by a modified version of the Boeing 737.

Since the E-2D’s external appearance will be close to that of the E-2C, a triangle symbol will be painted on the former’s nose — delta for D — to help crews distinguish it from older models on the carrier deck. The differences inside will be obvious.

Crew Multiplier

The E-2C has a 1970s era cockpit with round analog gages and tape displays. The D model will have a glass cockpit from Northrop Grumman Electronic Systems, featuring 17-inch multifunction displays for the pilots that can be configured to preference.

The system will allow the non-flying pilot, on a workload permitting basis, to join the three tactical operators in the back of the aircraft — the combat information center officer (CICO), air control officer (ACO) and radar operator (RO) — who will have larger displays and new workstations.

Mahr believes E-2Ds will pick up more assignments as they work increasingly in proximity to the shore, making a 25-percent increase in crew size without actually adding a new crew member an attractive idea. The concept is being tested in the E-2C now with laptop computers serving as tactical displays for the pilots.

E-2 pilots have always assisted the tactical officers with radio management and talking to other aircraft while loitering on station. But with the new system, they will have access to primary sensor data, allowing a much deeper role in the mission and relieving some of the workload in the back. Pilots will receive extra training in the use of tactical systems.

Mahr and Vice said the E-2D’s open architecture will accept whatever radios the services choose, whether it’s the Joint Tactical Radio System or something else. The E-2 community is experimenting with JTRS features such as wide band and unique waveforms using VRC-99 radios.

"Not if, but when JTRS becomes available, we will use JTRS," Mahr said.

But the philosophy behind E-2D communications is that the specific radio is not as important as an open architecture that allows growth and the ability to pass intelligence around the battle space, giving users information they need in a format they can use, in a way that makes sense for bandwidth, Vice said. Rapid advances in data storage capability can also help aggressive bandwidth management, he added.

The biggest changes to the E-2D airframe, a redesign of the fuselage and center wing section for more efficient, cost-effective production, will be invisible to the observer. The outer wing panels and empennage, with its four vertical stabilizers, are exactly the same. A more powerful variant of the Rolls-Royce T56-427 turboprop engine, with Full Authority Digital Engine Control — another improvement over the E-2C — spins larger generators to sate the aircraft’s greater hunger for electricity.

One noticeable change will be the addition of a refueling boom, part of the Navy’s request for the next defense budget. Booms will be added to E-2Cs in the fleet and come standard on the E-2D, Mahr said.

In-flight refueling capability comes as the result of a demonstration at Patuxent River Naval Air Station, Md., in 2006 in which crews proved an E-2C could safely maneuver behind and plug with both F/A-18E and KC-130 tankers.

Mahr said another year of flight tests are required before the booms enter the fleet. A training program must also be developed for Hawkeye pilots who don’t currently practice night formation flying, necessary for in-flight refueling.

Also, some modifications must be made, including the addition of external lights so the aircraft can be seen by other pilots during night refueling, as well as new cockpit lighting.

Just as important are the human factors involved with pushing the mission’s maximum endurance of 4.5 hours to beyond seven. Crew members are confined to their stations in a Hawkeye and stretching has to be done in a crouch, so the program is considering improved seats and cushions to make long missions more bearable, Mahr said.

Training for veteran Hawkeye pilots will mainly cover the glass cockpit and their new duties as the fourth tactical officer.

With a maximum take-off weight of 57,500 pounds, the D model will weigh 2,500 pounds more than the C, but essentially flies the same, according to the test crews. "That means the designers, as far as we can tell, have done a good job," said Mahr.

Vice noted that even with all the new equipment, the first E-2D Hawkeye is under its specification weight, a significant achievement for a new airplane, even one based on a proven design.

In addition to meeting weight goals, E-2D flight-testing was on schedule, also not an everyday occurrence for Pentagon aircraft programs.

"We flew when we said we would fly; the radar is on track and we’ll fly the next airplane with the radar on it when we said we would," said Mahr. "We’ve identified the challenges and [the industry team] has overcome most of them so far, everything that’s been thrown at them."

E-2D Advanced Hawkeye Configuration

Advanced Hawkeye Suppliers

Following is a partial list suppliers to the E-2D Hawkeye Sustainable Design & Development program, provided by Northrop Grumman.

Radar SystemLockheed Martin MS2-Syracuse
Radar and IFF Rotodome Antenna AssemblyL3 Communications Randtron
IFF SystemBAE Systems
Integrated CockpitNorthrop Grumman Electronic Systems
Engine ModsRolls-Royce
Electrical Generator SystemHamilton Sundstrand
Mission Computer and DisplaysRaytheon
Network File SystemLockheed Martin SI-Owego
Intercommunication SystemMathtech/Sechan Electric
Communications SuitePole/Zero (Tunable Filter/Amp.), DRS Technologies
Communications SuiteSelex Comm. S.p.A. (HF Radio), Rodelco-Radio Interface Unit
ESM SystemLockheed Martin SI-Owego
Standard AFCS Software ModsBAE Systems
Rotodome GearboxMPC
Fibre Channel Network SwitchHarris Corp.

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