In 1983, President Ronald Reagan supported a program designed to shoot down Intercontinental Ballistic Missiles (ICBM) which raised protest and skepticism -- if such a technology was even possible -- six years after the movie Star Wars debut. Billions of dollars were invested in a variety of research programs. The military has methodically researched a variety of concepts on how to defend against incoming nuclear missiles. SDI was born and today is managed by the U.S. Missile Defense Agency.
Among the concepts: Using a high powered laser to hit an ICBM and destroy it. Ground based systems made no sense for a variety of logistical and technical reasons. Airborne-based platforms made sense. Spaced-based systems would have been ideal, many thought.
Ground-based systems were never seriously considered because of many obstacles that could occur between the ground station and the target and the limited amount of area that it could protect.
Spaced based systems are ideal, but posed significant technical, financial and security challenges. Throughout the 1990's, the program evolved, and continues down two primary paths. One is using ground based missiles to hit opposing missiles such as the Patriot system and the second is using aircraft with the payload that is then fired to intercept an ICBM. The latter concept has continued development as a satellite attack platform.
Modifying the second approach evolved using large airborne platforms to house powerful high powered (as in multiple Megawatt) based lasers. The program offered several advantages. It's rechargeable, it can be stationed anywhere over the United States and its allies, and it can be above any obstacles between itself and the target. In 2004, a B-747-400, heavily modified to be used as the test platform, known as the YAL-1A, was built.
A Chemical Oxide Laser is housed in the aircraft and is going through testing to destroy short and long range ballistic missiles. On Wednesday just before 9 PM Pacific time, the second successful test was completed.
At 8:44 p.m. (PST), February 11, 2010, a short-range threat-representative ballistic missile was launched from an at-sea mobile launch platform. Within seconds, the ALTB used onboard sensors to detect the boosting missile and used a low-energy laser to track the target. The ALTB then fired a second low-energy laser to measure and compensate for atmospheric disturbance. Finally, the ALTB fired its megawatt-class High Energy Laser, heating the boosting ballistic missile to critical structural failure. The entire engagement occurred within two minutes of the target missile launch, while its rocket motors were still thrusting.
This was the first directed energy lethal intercept demonstration against a liquid-fuel boosting ballistic missile target from an airborne platform. The revolutionary use of directed energy is very attractive for missile defense, with the potential to attack multiple targets at the speed of light, at a range of hundreds of kilometers, and at a low cost per intercept attempt compared to current technologies.
If the program continues to have success, it could offer the U.S. and its allies protection against future attacks from rogue nations that have chemical, biological or dirty nuclear warhead based missiles.
Update: Photo's and video of test