Alliant Techsystems completed a successful test firing earlier today of a second-stage rocket motor for the U.S. Missile Defense Agency’s (MDA) Kinetic Energy Interceptor (KEI). This is the first in a series of static motor firings leading up to the program’s first booster flight in 2008. Northrop Grumman is leading the industry team charged with developing and testing a KEI capability under contract to MDA. Raytheon Company is responsible for developing and integrating the KEI system’s interceptor.

The second-stage rocket motor burned successfully to completion, demonstrating proof-of-concept of the motor assembly and its thrust vector control nozzle for this high-acceleration, high-velocity, and highly maneuverable missile. Initial test results matched expectations for rocket motor performance and integrity.

KEI is a mobile, land-based missile defense system that, when deployed, will be able to destroy a hostile threat during its boost, ascent or mid- course phase of flight.

ATK is the largest propulsion subcontractor on the KEI program. The company will produce first-stage rocket motors at facilities in Utah and will produce second-stage and third-stage rocket motors in Elkton, Md. The KEI canister launch eject gas generators will be produced by ATK in Rocket Center, W.Va.

ATK is a $3.1 billion advanced weapon and space systems company employing approximately 15,000 people in 23 states. News and information can be found on the Internet at .

Certain information discussed in this press release constitutes forward- looking statements as defined in the Private Securities Litigation Reform Act of 1995. Although ATK believes that the expectations reflected in such forward-looking statements are based on reasonable assumptions, it can give no assurance that its expectations will be achieved. Forward-looking information is subject to certain risks, trends and uncertainties that could cause actual results to differ materially from those projected. Among those factors are: the challenges of developing advanced weapon systems, changes in governmental spending for missile defense programs, budgetary policies and product sourcing strategies; the company’s competitive environment; the terms and timing of awards and contracts; and economic conditions. ATK undertakes no obligation to update any forward-looking statements. For further information on factors that could impact ATK, and statements contained herein, reference should be made to ATK’s filings with the Securities and Exchange Commission, including quarterly reports on Form 10-Q, current reports on Form 8-K, and ATK’s Annual Report on Form 10-K for the fiscal year ended March 31, 2005.