KEI Now Seen as Multipurpose Missile Defense Weapon

Navy Assessing Submarines, Aegis Cruisers as Possible Basing Modes for Interceptor

By RICHARD C. BARNARD
Editor in Chief

The Kinetic Energy Interceptor (KEI), a developmental weapon once relegated to a supporting role in missile defense, is now being cast as a leading player in the Pentagon’s multilayered Ballistic Missile Defense System.

The KEI initially was envisioned as a weapon designed principally to intercept hostile missiles in the first, or boost, phase of attack, which can last for as little as 180 seconds. This limited amount of time mandated a missile with enormous acceleration and power to get to the target quickly and destroy it on impact.

“We started with the notion that we wanted to work the boost phase,” said Terry Little, program director of the Missile Defense Agency’s KEI office. But MDA’s selection of a highly flexible kill vehicle for the KEI — which would be effective in other phases of the missile defense regime — helped convince agency officials that the missile could be a capable performer in the ascent and midcourse phases of a missile attack.

“Although we have characterized it as a boost-phase” weapon, the agency now views the KEI as the basis for a “multipurpose, multi-use interceptor,” Little said.

The ascent phase of an attacking missile’s flight occurs at 500 to 600 seconds after launch. Midcourse includes the apex of the missile’s flight at about 1,200 seconds. The KEI kill vehicle, or warhead, will use the seeker and electronics of the Navy SM-3 missile and the divert and attitude-control device being developed for another new missile, the Ground Based Interceptor.

Being developed by Northrop Grumman and Raytheon at a cost of $4.5 billion through 2010, the KEI is part of the Pentagon’s defensive system to protect the United States and its allies from hostile ballistic missiles. The system comprises an array of defensive missiles based on land and at sea and an airborne laser mounted on a Boeing 747 cargo plane, all linked together by a battle management system.

The KEI, which destroys its target by impact rather than an explosive warhead, is to be fielded as a ground-based missile in 2010 with a sea-based version to follow in 2013. Initial elements of the missile defense system, comprising two destroyers armed with SM-3 air defense missiles, are to be deployed in September.

If vision becomes reality, the broader application of the KEI now favored by agency officials has significant consequences for the national missile defense system. At approximately 12 meters long and 1 meter wide, the KEI will be twice the size of the SM-3 and attack its targets at more than twice its speed.

The SM-3 closes on hostile missiles at 3.7 kilometers per second. As a midcourse missile, the KEI’s engagement time expands from three to 20 minutes. Thus, it will have a vast engagement area, Little said, enabling a single battery of 10 missiles based in Italy to protect all of western Europe against missile threats from Iran. One battery based in Norfolk, Va., could protect the East Coast of the United States from a launch 300 to 1,500 kilometers off the coast. This rebuts the KEI’s critics, who charge that the costly weapon is essentially a one-country missile intended to defend against an attack by North Korea, Little said.

However, he concedes that the KEI would be of little use to defend against a hostile missile in its boost phase launched from a country with a large land mass. A successful defense in the boost phase requires that the defending missile be launched from “fairly close” to the target, such as 500 to 1,500 kilometers. Against large countries, that would require a space-based interceptor, he said.

There are other challenges ahead for the KEI. For example, defense against hostile missiles in the midcourse phase of attack is a complex assignment. During midcourse, the attacker releases decoys and chaff to spoof the defending missile into chasing the wrong target. Rubbish along the missile path poses the same problem. The defending missile must discriminate between the real target and nearby objects, and initial versions of the KEI are not designed to do that.

“If it’s an elaborate countermeasure, then we will have to get more sophisticated,” said Little. Another option is to use mini-kill vehicles “like we have in the technology arena” and adopt a different tactic. “You don’t necessarily discriminate, you just shoot everything that is up there,” he said.

Despite the KEI’s versatility, Little said the missile agency would proceed with its multilayered strategy intended to throw an array of defenses against attacking missiles. For example, the Airborne Laser and KEI both are boost-phase defenders.

Little said Navy response to the development of the KEI has been decidedly mixed. The “submariners … seem to be pretty excited” about the possibility of basing the KEI on one or both versions of the Ohio-class submarines, the Trident boats and the four boats being converted as guided-missile submarines (SSGNs) to fire Tomahawk missiles or transport special operations forces. However, surface Navy officials have been less electrified by the KEI, according to Little.

The Navy’s Surface Warfare Division is conducting a concept of operations study to determine the best sea base for the KEI. Results are expected in September.