Focus moves to larger Embraer jet for Aerial Common Sensor programme, but other aircraft may be considered

In a dramatic U-turn, the US Army and Lockheed Martin have dropped the Embraer ERJ-145 as the platform for the Aerial Common Sensor (ACS) after deciding it is not big enough to perform the mission. They have begun the process of selecting a replacement.

The army’s evaluation is understood to be focusing on a new special mission variant of the Embraer 190 as the replacement. However, the Brazilian manufacturer’s future in the programme is not assured.

Another candidate being reviewed is the Gulfstream G550, which is larger than the G450 model that lost in the competition last year. Also in the running is the Bombardier Global Express, used Boeing 717-200s and perhaps an Airbus aircraft, such as the A318.

“We are collecting information on various platforms to better understand the class of larger aircraft and specific aircraft in that class that best satisfy ACS mission needs,” says Lockheed.

The pending re-selection of the ACS platform is intended to overcome the recent discovery of integration problems with the ERJ-145. Power, growth and weight estimates have ballooned to exceed the aircraft’s limits.

“Through the maturation of system design, we have identified additional integration weight,” says Lockheed. “We are assessing the cost/schedule/technical implications of a larger aircraft.”

The army says the ACS development team is “mitigating size, weight, power and cooling challenges”, and adds: “No final decision has been made on airframe selection at this juncture.”

Meanwhile, the US Navy’s plan to formally join the programme has been stalled pending the new aircraft selection, although the service remains committed to ACS. Under the baseline strategy, the army has plans to buy 38 aircraft, and the navy would add 19. The power and weight challenges are understood to be driven by ACS’s highly complex sensor package, which fuses signals, imagery and signature intelligence apertures into one system.

When the Lockheed team was awarded the ACS contract in August, Embraer’s role in the programme was hailed as a breakthrough for foreign companies seeking to penetrate the US defence market.

STEPHEN TRIMBLE & GRAHAM WARWICK/WASHINGTON DC

Source: Flight International