Farnborough Air Show

CAEW is a bridge to the future

 - July 15, 2008, 11:46 AM

IAI’s Gulfstream G550-based conformal airborne early warning & control (CAEW) aircraft is making its world debut here at Farnborough. The aircraft has flown with the Israel Air and Space Force only since February, and its appearance here was not confirmed until a few days before the show. Feedback from the first months of operation has been excellent, according to IAI, highlighting the capabilities of what the company describes as a “third generation” of phased-array AEW aircraft.

“We have moved from the first generation of large phased arrays, through a fixed dome array, and now we have dual-band conformal arrays,” Avishai Izhakian, IAI’s deputy general manager, marketing and business development for the Elta AEW division, and former CAEW program manager told AIN. “It’s like the mobile telephone. Each new step means smaller and lighter systems, but with more powerful capability. That is our philosophy: turning kilograms into kilobytes.”

Izhakian sees CAEW as a “gateway to the future.” The natural progression is to ultimately move full-scale AEW systems aboard UAVs, but that will only be possible when power requirements have decreased and system size reduced. That day is some way off, but the current CAEW is taking a major step along that path.

Gulfstream Platform
IAI chose the Gulfstream as the basis for CAEW as it offers excellent performance, comfort and cost figures. It can reach 41,000 feet 20 minutes after takeoff, and stay there for up to 10 hours. Cabin altitude remains at a very comfortable 3,500 feet.
The CAEW’s Elta EL/M-2085 is the world’s first dual-band AEW system. The main L-band side arrays have multiple transmit/receivers in a low-drag fairing, but with the individual processors–normally located in the array itself–mounted in cabinets in the forward cabin. Completing the 360-degree coverage are S-band antennas in the nose and tail. According to Izhakian, L-band is better for the AEW role, but S-band has to be used due to the small aperture size available in the forward- and rear-facing arrays. All elements work simultaneously.

A key feature of the radar and its associated IFF equipment is that it can scan vertically as well as horizontally, so that radar performance doesn’t degrade as the aircraft banks. The radar uses monopulse technology for accurate height-finding, and can accurately follow targets that are maneuvering hard. The quick revisit time allows tracks to be established in about four seconds, with full four-dimensional information including accurate velocity.

Partnering the radar is a sensitive electronic support measures system located in fairings above the nose and under the wingtips. This uses differential time of arrival techniques to give accurate passive tracking to augment the radar-generated tracks.
CAEW is also well-connected, with a range of communications equipment. A line-of-sight datalink is installed under the rear fuselage, while the fin-top fairing houses satellite communications that remain unobstructed through most aircraft maneuvers. The datalinks allow the system to be monitored or operated from ground stations.

In the cabin are six operator consoles, each equipped with a 24-inch color display. As the CAEW is a fully networked asset, it can receive data from many offboard sensors. For operators, that means they can call up and display information regarding weather or intelligence at the click of a mouse. Many of the functions are automated, such as the handoff of target data to interceptors. The onboard workload is primarily battle management rather than systems operation.

The CAEW is one of a family of special mission aircraft that IAI Elta is developing, all based on the G550 airframe. The AISIS signals intelligence platform is already in service, while the MARS2 battlefield SAR/GMTI radar platform is currently in the engineering stage. MARS2 is being developed to an Israeli MoD requirement, but is “a few years” away from operational hardware.