By Marina Malenic

SEATTLE–Australia has now received four of a planned fleet of six new airborne early warning and control (AEW&C) aircraft after years of delays, and prime contractor Boeing [BA] believes the program has overcome most of its major technical hurdles.

The four AEW&C aircraft, known as Wedgetails, were delivered to the Royal Australian Air Force (RAAF). They are scheduled to go through a “minor retrofit” this year, Egan Greenstein, Boeing’s senior manager for AEW&C business development, told Defense Daily last week.

“The program went through some difficulties, but they [the RAAF] are very happy with what they have now,” said Greenstein.

The program has suffered repeated delays since its inception 10 years ago. There have been development problems with the Wedgetail’s Northrop Grumman [NOC]-built multi-role electronically scanned array (MESA) radar, Boeing’s design for the modified 737 air frame and a BAE Systems Australia suite of electronic support measures.

The first major problem involved signal distortion from the MESA radar, which Greenstein said has since been resolved. The second challenge was refining the software for constantly changing planned capabilities as electronically scanned array radar technology matured.

Last year, Australia commissioned Lawrence Livermore National Laboratories to study whether the MESA radar can meet its requirements. The study concluded that the architecture is sound but that software changes were needed.

“Software development has been one of the most challenging parts of the development process,” said Greenstein.

The aircraft is designed for simultaneous air and sea search, fighter control and area search. The MESA radar is located on a dorsal fin on top of the fuselage referred to by designers as the “top hat.” Legacy aircraft like the U.S. E-3 Sentry airborne warning and control planes use rotating, mechanically scanned radars. The MESA radar is designed to “track while scanning.”

“I can maintain a full surveillance while a tracking beam is on multiple targets,” Greenstein said.

The cabin features eight operator consoles with sufficient space for four more. The RAAF plans to operate 10 consoles with space for two more, according to Greenstein. Greater computing power allows the easier identification of objects whether they are moving or not.

Meanwhile, Boeing’s fourth quarter earnings statement includes a new charge against earnings valued at $136 million on the AEW&C program as a whole, which includes orders by Turkey and South Korea. According to the statement, the writedown is a consequence of “additional software development and testing required for acceptance of the Wedgetail aircraft” by the RAAF. The charge also covers the “resolution of issues associated with the test program” for Turkey.

Boeing has previously accepted charges on the program worth more than $1 billion.

Turkey has ordered four AEW&C aircraft under its Peace Eagle program, and South Korea is also awaiting four for its Peace Eye program. Seoul’s first delivery is now scheduled for next year, with three more planned for 2012. Boeing is still formulating a delivery schedule for Turkey.

India and the United Arab Emirates have also expressed interest in the program, Greenstein said, and Italy is said to be considering it.

Australia has set an operational date of 2012 for all six planes. The country’s coastline is currently monitored by ground radars.

Boeing must still certify the Wedgetail’s electronic-support measures system, which consists of 84 antennas installed around the plane’s exterior that alert operators and the craft’s flare and chaff system about incoming threats. Greenstein said the company is on track to do this by mid-year.