A flight trial for the U.S. Missile Defense Agency’s Ground-Based Midcourse Defense (GMD) program slated for this fall has slipped to early next year, according to an agency official.

The test is to be the most complex to date, featuring a head-on engagement of the Ground-Based Interceptor (GBI) against a separating target with countermeasures, GMD Project Director Carlos Kingston said in August. It was slated for September, but is now expected by February, according to MDA spokesman Rick Lehner.

This will be an attempt to test against a target similar to that used in a December 2008 test that was deemed unsuccessful because the countermeasures did not deploy as planned.

The delay until early 2010 was due to “recently updated target model and simulation predictions used for mission objective development,” Lehner said.

In the meantime, the agency is preparing for the final trial of the FTX-06 series of tracking exercises designed to showcase the capabilities of the Aegis 4.0.1E weapon system. This system was recently installed on the USS Lake Erie, and the software is designed to provide better target discrimination for the sea-based leg of U.S. the missile defense shield.

Lehner says that a new target, a separating Aegis Readiness Assessment Vehicle (ARAV) C, will be launched early this month so the new software load can characterize it. The data will be used for future modeling and simulation and performance predictions for more complex targets. Meanwhile, the software systems are undergoing a debug and test phase now in preparation for delivery in 2011, Lehner says.

Prior to the test this month, several FTX-06 events have taken place.

During the first in July, the new Aegis system was used to characterize a short-range unitary ballistic missile target. Three Aegis-equipped ships conducted simulated engagements.

The second and third FTX-06 events took place in mid-October and each included the launch of a short-range separating ballistic missile target called the ARAV-B. The USS Lake Erie detected and tracked the target using the new software, and other Aegis-equipped ships conducted similar engagements.

The new Aegis software will be used to execute missions using the new Raytheon SM-3 Block IB missile, which will feature a new two-color infrared sensor and throttleable divert and attitude control system.

Photo: MDA