The Missile Defense Agency announced yesterday that it had conducted the first flight test of a GBI interceptor since its failed FTG-06a intercept test in December 2010.

The test, labeled CTV-01, did not involve a target, and thus no actual intercept was attempted.   Instead the kill vehicle carried out a series of pre-planned maneuvers in order to validate the identification of the problem that caused the failure of the December 2010 test.  MDA officials announced that preliminary indications were that the test had been successful, with all components performing as designed.  If so, the test would represent a crucial step in towards recovering from the FTG-06 and FTG-06a failures, which have delayed the testing program by at least three years.

The launch of the GBI Interceptor, January 26, 2012.  (photograph from http://www.mda.mil)

Background

CTV-01 was needed because of the failure of FTG-06a in December 2010, which was the most recent intercept test of the GMD system.  FTG-06a itself was a repeat of the FTG-06 test of January 2010, in which the homing Exo-Atmospheric Kill Vehicle (EKV) also failed to hit its target.  The last successful GMD intercept test was FTG-05 in December 2008.

FTG-06 and FTG-06a were the first two flight tests of the new Capability II (CE-II) version of the EKV.  The development and deployment of the CE-II kill vehicle was necessitated by obsolescence issues with the original CE-I version of the kill vehicle.  The first GBI interceptor armed with this new CE-II kill vehicle was deployed in a silo in Alaska in October 2008 and ten of this version  were deployed in silos (out of a total of 30) at the time of the FTG-06a test failure.

The failure of FTG-06a was an extremely serious setback for the GMD program.  Unlike FTG-06, in which the EKV failed because of a quality control problem during its assembly, the failure in FTG-06a appears to have been caused by a design flaw in a part that was new to the CE-II version of the EKV.  If so, while this problem wouldn’t affect the older CE-I EKVs, it meant that the ten CE-II GBIs already in silos, as well as those in various phases of production, would all likely share this same flaw.

As a result, shortly after the FTG-06a failure, MDA removed the ten deployed GBIs with the CE-II version of the EKV from operational status (although they remained in their silos) and halted deliveries of new EKVs.

The cause of the FTG-06a failure was apparently difficult to pin down, with the MDA director Lt. General Patrick O’Reilly telling Congress that it was a problem “that could not be replicated on the earth.”  Through extensive (and expensive) ground-testing, MDA was eventually able to identify what it believed was the cause of the problem.  According to the publicly available information, the problem appears to be caused by vibrations from EKV’s maneuvering thrusters affecting its inertial measurement unit.  For more details about the problems with FTG-06 and FTG-06a, see my post of December 21, 2012.

What the Test Means.

In addition to numerous ground tests, MDA planned two flight tests to demonstrate that the problem that caused the FTG-06a failure had been correctly identified and fixed.  In the first of these two tests, a CE-II kill vehicle with the suspected defective part (but with unspecified “mitigations” for the problem it caused) would be flown on a non-intercept mission.  This is the test that was conducted yesterday.  If this first test succeeded, as the MDA has indicated that it believes it has, then a second test would be conducted shortly afterwards.

This second test, designated as FTG-06b, would be an intercept test using a CE-II EKV with the new replacement part.  This test, now planned for this spring or summer, if successful would for the first time demonstrate an intercept with the CE-II kill vehicle.  GMD testing would then continue with FTG-08, an intercept test using a two-stage version of the GBI interceptor, which is unlikely to occur before the second half of 2014. (See the post of May 9, 2012 for test schedule).

The consequences of a failure in CTV-01 would have been severe.  It would have inflicted further delay in confirming the intercept capability of the new version of the kill vehicle, already more than three years behind schedule, and which even if CTV-01 and FTG-06b are successful will end up costing over a billion dollars.  In fact, MDA had indicated if CTV-01 had failed, then it would consider resuming testing with the original CE-I kill vehicle.