PROMONTORY, Utah, Oct. 24, 2011 -- Northrop Grumman (NYSE:NOC) and ATK (NYSE:ATK) successfully ground-tested a Minuteman III Stage 1 solid rocket motor for the United States Air Force as part of the Minuteman Solid Rocket Motor Warm Line (SRMWL) program at ATK's test facility in Utah.

This test was the second Production Quality Assurance (PQA) ground test of the SRMWL Stage 1. The first Stage 1 PQA was successfully tested on March 24, 2011. The SRMWL is designed to sustain critical propulsion-related skills to ensure the weapon system can be sustained. The Minuteman III program began in 1966 and currently maintains 450 missiles deployed at three missile wings.

"We prepare for and assess every ICBM test very rigorously, and the success of this Stage 1 test provides one more point of assurance of the integrity and reliability of the ICBM weapon system today and the solid rocket motor industrial base for the years to come," said Tony Spehar, vice-president of Northrop Grumman's Missile Systems business unit. Northrop Grumman is the ICBM prime contractor and responsible for overall sustainment of the ICBM weapon system.

As part of the SRMWL program, up to ten motor sets over two years will be manufactured by ATK under contract to Northrop Grumman at ATK facilities in Utah. The objective of the SRMWL's PQA testing is to demonstrate the motors perform as designed. Each of the three stages is tested every year. Ground tests for Stage 2 and 3 are conducted in altitude chambers at Air Force's Arnold Engineering Development Center in Tennessee and each was successfully tested this past summer.

"This successful test demonstrates that the motors produced under the warm line contract are fully representative of deployed first stage ICBM motors," said Scott Lehr, ATK Aerospace Systems vice president and general manager of Strategic and Commercial Systems. The warm line program also maintains the critical skills, infrastructure and supplier base necessary to produce ICBM propulsion hardware in the future."

The refurbished Stage 1 case used in this test originally entered operational inventory in January 1961. ATK has manufactured over 4,000 Minuteman motors over the life of the program. The company recently completed a successful 10-year Minuteman Propulsion Replacement Program that produced approximately 1,800 re-manufactured motors.

About Northrop Grumman

Northrop Grumman is a leading global defense company providing innovative systems, products and solutions in aerospace, electronics, information systems, and technical services to government and commercial customers worldwide. Please visit www.northropgrumman.com for more information

About ATK

ATK is an aerospace, defense, and commercial products company with operations in 23 states, Puerto Rico, and internationally, and revenues of approximately $4.8 billion. News and information can be found on the Internet at www.atk.com .

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: changes in governmental spending, 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, please refer to ATK's most recent Annual Report on Form 10-K and any subsequent quarterly reports on Form 10-Q and current reports on Form 8-K filed with the U.S. Securities and Exchange Commission.

  CONTACT: Northrop Grumman Media Contact:
         Bob Bishop
         Phone: 310-812-5227
         E-mail: bob.j.bishop@ngc.com
         
         ATK Media Contact:
         Trina Patterson
         Phone: 801-699-0943
         E-mail: trina.patterson@atk.com