26 February 2008: It is a rare moment in the life of a military system to get an actual operational scenario even before attaining total technological maturity. For the U.S. Missile Defence Agency (MDA), which was in desperation over development hurdles on its Ballistic Missile Defence (BMD) programme, the moment of reckoning came on February 21st when it was assigned the task of intercepting and destroying a dysfunctional military satellite which threatened to hit the Earth with hazardous fuel onboard. For the first time ever, a BMD system was to be employed for a real time outer space operation, which ironically happened to be an Anti-Satellite (ASAT) function.

The much-maligned MDA silenced its long-time critics by justifying its raison d'être through a seemingly successful interception and destruction of the dysfunctional satellite on February 21st. For this mission, the MDA used the ship-based Aegis system, which is its only operational BMD currently deployed in the Pacific and Asian seas. The main Aegis interceptor used is the Standard Missile-3 (SM-3) with 250 km range, which has a hit-to-kill technology to intercept an incoming threat in Exo-atmosphere (outside Earth's atmosphere). As per the MDA's multi-stage interception plan, the USS Lake Erie (Ticonderoga class cruiser) was to launch the first SM-3 and possibly a second one, if the first intercept fails. A second ship, the Decatur (Arleigh Burke class destroyer) was to launch the third SM-3 if the initial two attempts fail. The intercept convoy, deployed off the Hawaii Islands, tracked the satellite in its orbit and launched the first SM-3 when the intercept window was opened on February 21st morning during the satellite's orbiting over the intercept region. Much to the delight of the mission control, the first SM-3 launched from USS Lake Erie at an altitude of 130 miles just outside the Earth's atmosphere destroyed the satellite on impact thus taking out the target in the first hit.

This epochal mission was warranted as the satellite became dysfunctional after it was launched 14 months ago, and thereafter began a slow descent towards Earth. The primary objective of the mission was to destroy a fuel tank aboard the satellite which had over 450 kg of toxic hydrazine. Had the tank survived a re-entry into the Earth's atmosphere, it could have caused serious danger to the point of impact, especially over a population centre. Though it is yet to be confirmed whether the intercept had destroyed the tank, the mere fact that this was the first ever operational intercept in exo-atmosphere by a U.S. BMD is in itself a major milestone not just for the U.S. BMD programme, but also for the global evolution of BMD technology.

The successful intercept assumes further significance for the MDA which was reeling under criticisms from various quarters for its tardy development programme, leading to Congressional insinuations and budgetary cuts. While the Agency has sensibly deployed an operational system in the form of the Aegis BMD, it only partially clears doubts on whether the Ground Based Mid-Course Defence System (GBMDS), the main U.S. mid-course interceptor for exo-atmospheric interception, is capable of undertaking similar tasks in future. Employing the Aegis BMD carried a calculated technological risk as the system was assigned with the complex task of intercepting a target cruising at a speed of 22,000 miles per hour. The Aegis was hitherto tested only against slower-moving targets in simulated conditions.

The GBMDS and the Kinetic Energy Interceptor (KEI) are being developed to operate at this speed in exo-atmosphere. However, as these systems are still under development, the MDA had no go but to employ an operational system for this high-risk task. The only other choice would have been to use an Anti-Satellite (ASAT) system, which the U.S has used during the Cold War but subsequently terminated after the campaign against space weaponisation. The usage of ASAT systems for this mission was considered a political risk. Washington had strongly criticized the recent ASAT test by China for destroying a defunct satellite, and had termed it as a provocative step towards space weaponisation. Taking the same method to destroy a non-military asset would have hypocritical. Moreover, Russia and China lost no time in criticizing the U.S. plans saying it would harm the other space assets and initiate space weaponisation trends.

Though the SM-3 or GBMDS are designed as exclusive anti-ballistic missile systems, their ASAT spin offs have never been underestimated. While the debate on BMDs had rarely touched upon their ASAT dimensions, this intercept of a space asset by a BMD system might trigger a conundrum on the usage of BMD systems in outer space. However, U.S. officials had tried to reassure the international community by arguing that unlike the Chinese effort which was to test an ASAT weapon, this mission was to intercept a falling satellite which was ultimately done in a much lower orbit than most working satellites.

Such arguments notwithstanding, the successful intercept of February 21st would clearly go down as a significant phase in the evolution of the BMD technology. More importantly, the MDA can now confidently convince its stakeholders on the reliability and efficacy of such systems in undertaking successful interceptions not just in simulated but also in actual operational conditions. This successful intercept could thus be deemed as a testament to the feasibility of ballistic missile defences. Above all, it heralds the age of missile defences.
The writer is with the Institute for Defence Studies and Analyses, New Delhi. He can be contacted at: vinujnu@gmail.com