Fiscal Year 2000 activity included initial test flights for the DT at the White Sands Missile Range. The DT consists of firing both control test vehicles (CTVs) and guidance test vehicles (GTVs). CTVs are ESSMs with inert guidance sections programmed to execute maneuver patterns. GTVs are ESSMs with guidance sections for homing on targets. The fourth CTV flight test was conducted in November 1999. The first GTV flight test was conducted as a combined CTV/GTV flight in March 2000. GTV-2 was fired at a sub-sonic target drone in July 2000. GTV-3 was fired at a supersonic target in August 2000. GTV-4 was fired at a maneuvering target drone in November 2000. GTV-5 was fired at a low altitude, close-range, sub-sonic target in December 2000. The GTV results will serve as the basis for an OA to support an LRIP decision. Tests were conducted in accordance with a DOT&E-approved TEMP and OA plan.

Activity also included preparation for the two phases of DT/OT planned for FY01: Aegis S-Band testing at the White Sands Missile Range (February-May) and at-sea testing on the Self Defense Test Ship (planned to start in June). Results of this testing will serve as the basis for a second LRIP decision.

CTV Results. Primary objectives of the four CTV flights were to demonstrate kinematic capability and aerodynamic control during high G maneuvers, evaluate autopilot stability, and collect data to validate simulations. Autopilot performance was closely monitored during these flights, with design changes implemented as the flight series progressed. A "tactical" autopilot was used in the third flight, but performance was marred by loss of roll stability during an early maneuver, resulting in high roll rates that exceeded the capability of the inertial measurement unit. As a result, the autopilot gains were adversely affected for the remainder of the flight. The initial loss of stability was caused by incorrect entries in the autopilot software. A problem that persisted at least through the first three flights was that the rear reference antenna, located near the rocket motor exhaust, suffered thermal damage to its radome, which could have affected RF properties. The seeker antenna radome came apart during the first CTV flight test and, although a failure cause was believed determined at the time, subsequent radome failures during two GTV flights helped isolate the problem to radomes of a particular make (discussed under GTV phase below). A battery failure occurred during the second flight test. The failure cause was determined and the problem was fixed. The fourth CTV flight, conducted from a vertical launch cell, resulted in the thrust vector controller failing to detach from the rocket motor. Failure cause was determined to be a missing g-switch in the control actuation assembly; processes have been implemented to preclude recurrence. The CTVs were launched from both a MK 29 rail launcher and a MK 41 vertical launcher.

GTV phase: Three GTVs were flight-tested during FY00, and two more have been fired in early FY01. GTV-1 was modified to incorporate test objectives from CTV-4. The missile executed the programmed CTV-4 maneuvers, then locked on and guided to successful intercept with a sub-sonic, "middle of the envelope" target drone augmented to increase its radar cross-section. GTV-2 was launched at a sub-sonic drone, at higher altitude than GTV-1, but without the increased radar cross-section. The ESSM seeker antenna radome came apart during flight, precluding terminal guidance on the target. GTV-3 was launched at a supersonic target. The seeker antenna radome on this ESSM also came apart during flight, just as the ESSM began terminal homing on the target. As of this writing, the cause of the radome failures appears to be thermally-induced stress experienced in the high acceleration environment of ESSM. All three radomes that failed were from the same source (which no longer produces them). Of the radomes that performed successfully, three were from a second source, and one was from the first source. The fact that it did not fail is attributed to the less demanding maneuver profile. GTV-4 was launched from a vertical launcher at a sub-sonic, maneuvering target, with successful intercept at medium range and low altitude. GTV-5 was launched from a vertical launcher at a sub-sonic target, with successful intercept at close-in range and low altitude.

Among the significant limitations accompanying the testing of ship-launched missiles at the White Sands Missile Range, that will qualify conclusions drawn from the results of the testing, is the decidedly non-maritime nature of the high desert environment. The harsh environment encountered when engaging sea-skimming ASCMs cannot be adequately represented because targets cannot be flown low enough and the radar reflectivity characteristics of the sea surface cannot be represented. Safety zones surrounding the launcher preclude flying targets directly toward the launcher, creating a crossing aspect that is not present in a self-defense scenario at sea. Further, the fire control system at White Sands Missile Range differs in many respects from those used on ships firing ESSMs.

Self Defense Test Ship Phase. The DT/OT scheduled for FY01 on the Self Defense Test Ship promises to be very realistic, with the opportunity to learn more about ESSM capability in the actual operational environment. The SDTS combat system represents that on non-Aegis ships using the MK 29 rail launch system.

OPEVAL and FOT&E. Although OPEVAL is considered adequate, with the possible interoperability exception noted below, a new ASCM threat has appeared for which there is no credible surrogate to use as a target. Given the time required to obtain such a surrogate, this is expected to be an issue for examination during FOT&E. Limitations in the Aegis Weapon System Baseline 6.3 computer program and shipboard illuminator radars will preclude testing ESSM's capability against surface targets.

Interoperability with Aegis Weapon System. ESSMs are intended to provide close-in defense of Aegis ships against anti-ship cruise missiles, with Standard Missile providing interceptor capability at longer ranges (both self-defense and defense for other ships). There are circumstances where the Aegis Weapon System could be controlling both ESSMs and SM-2s simultaneously. This is primarily an Aegis Weapon System (Baseline 6.3) issue that requires operational testing, either during the ESSM OPEVAL or during DDG 51 FOT&E.