EMB-145SA and RS Brazil's New Eyes in the Sky

Aerospace Power Journal, Winter, 2000 by Capt Gilles Van Nederveen

CAPT GILLES VAN NEDERVEEN, USAP [*]

Editor's Note: PIREP is aviation shorthand for pilot report. It's a means for one pilot to pass on current, potentially useful information to other pilots. In the same fashion, we intend to use this department to let readers know about aerospace-power items of interest.

ADVANCES IN RADAR, computer, and data-link technology have allowed airborne surveillance platforms to migrate from large commercial jetliners to smaller commuter-sized aircraft. The Brazilian air force has two new platforms entering service that will undoubtedly find their way into other air forces.

The EMB-145 airborne early warning and control (AEW&C) surveillance aircraft (SA), designated R-99A by the Brazilian air force, and the EMB-145 remote-sensing (RS) aircraft are both derivatives of the Embraer ERJ-145 regional jetliner, which has enjoyed worldwide commercial success. American air carriers use the 50-seat jetliner on regional routes throughout the United States. Both military variants were developed for Brazil's Sistema de Vigilancia de Amazonia (surveillance system, Amazon region) program, made up of both airborne- and ground-sensor systems designed to monitor activity throughout the Amazon basin.

The Brazilian air force currently has five EMB-145 AEW&Cs (fig. 1) on order and will assign them to the 2/6 Grupo at Anapolis Air Base near Brasilia, the federal capital of Brazil. To equip the aircraft to accomplish surveillance tasks, engineers had to strengthen its fuselage, install a more powerful auxiliary power unit, and add fuel tanks. The most visible change is the Swedish Erieye active phased-array radar, which is pylon mounted with a forward pitch along the top of the fuselage. Rather than a conventional rotodome, the Erieye is a fixed, pulse Doppler, dual-sided, and electronically scanned antenna operating in the E/F band. [1] Consisting of 192 transmitter/receiver modules, the Erieye provides 360-degree coverage with optimum-range performance achieved within a three-hundred-degree sector. Capable of detecting a fighter-aircraft-type target up to 186 miles away, [2] the Brazilian version of the Erieye has been optimized for detecting slow, low-flying targets typically encountered in border incursi ons.

The Brazilian air force's version of the aircraft will have four operator consoles and provisions for a relief flight crew of two-a pilot and copilot. All available systems functions can be controlled from individual consoles, thereby allowing operators to perform multiple functions rather than being role-dedicated. The aircraft is also equipped with a UHF data link, Global Positioning System capability, an electronic and communications intelligence system, and an improved radio suite. The data link will allow the R-99A to integrate data in real time with ground stations and airborne elements.

Capable of eight-hour endurance, these aircraft also have a high dash speed--Mach 0.78--allowing them to quickly reach operational patrol areas. In theory, four aircraft are enough to maintain two around-the-clock patrol missions, with one aircraft on continuous ground alert for more than 30 days.

The Brazilian air force is currently test-flying two R-99As, with Raytheon E-Systems doing the system-integration work in Greenville, Texas. The Brazilian air force should receive all of its aircraft by 2002. As a side note, the Greek air force has been the first export customer of the AEW&C version, and its four aircraft are scheduled to be delivered between 2002 and 2004. However, the Greek version will have an additional operator console, for a total of five. Systems-integration work will be carried out either in the United States or in Europe; this part of the contract is still subject to negotiation.

With a price tag of $200 million, the EMB-145 Erieye combination fills an emerging market niche. The price of the US Air Force's E-3 airborne warning and control system (AWACS) aircraft and newer systems such as the Wedgetail [3] or Phalcon [4] is simply too high for most countries. The combination of a radar and a commuter-type aircraft, however, has brought down the price. The original Swedish air force Saab 340 Erieye combination has not enjoyed any export success due to its lack of endurance. Most likely, the Brazilian aircraft/Swedish radar combination will enjoy considerable export success as other countries discover the affordability of the new AEW&C platform.

The EMB-145RS, designated R-99B by the Brazilian air force (fig. 2), is designed to monitor exploitation of natural resources, environmental and river-pollution control, economic activities, ground occupation, and illegal activities. Its primary sensor is a Canadian-made integrated synthetic-aperture radar-imaging system mounted in an underfuselage bulge with auxiliary antennas beneath the wing roots. It operates in a D-Band [5] mode and generates three-dimensional imagery. Other sensors are a forward-looking infrared/TV system mounted behind the nose-wheel bay, an ultraviolet/visible/infrared line scanner, and an electronic and communications intelligence system. Using a data link and an improved radio suite, the aircraft will be able to exchange data with other airborne platforms and ground stations.