Markets for radar aircraft remain robust, says Boeing.

The market for airborne early-warning and control aircraft is expected to grow, as airframes continue to age, said industry officials. The average age of current AEW&C airframes is 17 years.

Users of AEW&C platforms are expected to upgrade these systems, to extend their operational life as a much as possible. Meanwhile, companies such as Boeing and Northrop Grumman are marketing new replacement options, such as smaller jets with electronically-scanned radar. Sixteen nations today operate approximately 220 AEW&C systems.

An AEW&C aircraft typically consists of a large radar mounted on a big jet, such as a Boeing 707 or 767. It is used by nations to monitor portions of the airspace. One of the most widely used systems today is the Boeing E-3 Sentry AWACS. Boeing officials said the AWACS is expected to fly until 2035, while the company is positioning its smaller 737 platform to become the replacement for the AWACS in the future.

There are 70 AWACS around the world today. The United States is leading the pack with 33, followed by NATO with 17, United Kingdom with seven, Japan with four, France with four and Saudi Arabia with five.

For most countries outside NATO, AWACS is too expensive to purchase and maintain, each platform costing at least $500 million and up, depending on the features.

Allen Ashby, Boeing's vice president for airborne intelligence, surveillance and reconnaissance, said AWACS customers are planning major enhancements to their platforms.

The United States has not yet decided exactly what platforms it will buy to replace the AWACS, currently operated by the U.S. Air Force. The service is funding a notional multi-sensor aircraft, called the MC2A (multi-sensor command and control aircraft) program, which would replace the AWACS, the signals-intelligence Rivet Joint and the Joint STARS ground surveillance platforms. A rest-bed currently in development uses a 707 Boeing jet.

To AWACS customers and to nations seeking an AEW&C capability for the first time, Boeing is offering a system that uses the smaller 737 jet as a platform and features Northrop Grumman's multi-role electronically scanned array (Mesa) radar. It is informally known as Wedgetail, because that was the name of the Australian program that selected the 737 system.

In contrast to the 30-foot diameter rotating radar-dome antenna found in the AWACS, the Wedgetail system has a "top hat" 25-by-30-foot antenna. The Mesa has a steerable electronic beam, which helps achieve uniform coverage our to 190 nautical miles, said Ashby. An integrated identification friend-or-foe system is combined with the primary radar.

Boeing is also promoting the potential capabilities of the AEW&C system as a control platform for unmanned aerial vehicles, such as the Global Hawk. "UAV control is downstream, some time in the future," said Ashby.

Boeing recently signed an agreement with Turkey for the purchase of four Wedgerail-style AEW&C systems, a deal worth about $1.5 billion. Six Turkish companies will participate in the program as subcontractors. The fist platform will be built at Boeing's plant in Seattle, while the rest will be produced in Turkey.

Boeing also is targeting South Korea, Italy and Spain as potential customers.

According to Boeing, the 737's operating cost is one third of a 707. The company is marketing the aircraft as more than an airborne radar. "It does get the air picture, but it looks for cruise missiles as well," said Ashby.

In the international AEW&C market, the Wedgerail system competes in some nations against Northrop Grumman's E2C Hawkeye AEW&C aircraft, which is the U.S. Navy's airborne surveillance platform deployed on aircraft carriers.

A future version, called the Advanced Hawkeye, will have an electronically scanned array, which would replace the currently mechanically scanned rotating radar. The company said the aircraft will keep its trademark rotor dome and the new radar will be designed to fit within that space.

Outside the United States, the Hawkeye has been sold to France, Taiwan, Japan, Singapore and Egypt. The company expects to deliver three new aircraft to France and Taiwan in 2003 and 2004. Also, Northrop Grumman is courting new customers in the United Arab Emirates, Malaysia, Italy and the United Kingdom. Britain is considering the Hawkeye for its Maritime Airborne Surveillance and Control program, which is slated to launch in 2006.

The Advanced Hawkeye is expected to enter the U.S. Navy's fleet in 2009.

Northrop Grumman is implementing a new IFF (identification friend or foe) system with a range of 300 nautical miles. The project engineers will add a lot of geographic features to the system so that pilots can ask for names, cities, roads and railroads, said Arthur Fischer, project engineer for AEW programs.

IFF systems for platforms flying over water can be tricky, said Fischer. The next-generation RMP/Advanced Hawkeye will also have theater missile defense capability, multi-sensor integration, a new communications suite and generators.