ATK Conducts Successful Full-Scale Space Shuttle Motor Test

Minneapolis, June 11, 2004 – ATK (NYSE: ATK) successfully conducted a static
test firing of a full-scale Space Shuttle Reusable Solid Rocket Motor (RSRM)
yesterday. The test took place at ATK Thiokol’s Promontory, Utah, facility.

The Flight Support Motor (FSM) program verifies functionality of RSRM
components, materials, and processes while it evaluates and certifies
various design, process, and supplier changes for the RSRM flight program.

Initial results indicate that ATK achieved all 76 test objectives. Many of
the test objectives will be introduced into future Space Shuttle launches.
The test motor fired for two minutes, which is the length of time the RSRMs
fire during an actual Space Shuttle launch.

ATK’s Space Shuttle RSRM is the world’s largest solid rocket motor ever
flown and the first designed for reuse. The reusability of the RSRM case and
nozzle hardware is an important cost-saving factor for the nation’s space
program. From ignition to end of burn, each RSRM generates an average thrust
of 2.6 million pounds and burns for approximately 123.6 seconds. Each motor
is just over 126 feet long and 12 feet in diameter. The entire booster –
including nose cap, frustum, and forward and aft skirts – is approximately
149 feet long. Of the motor’s total weight of 1.25 million pounds,
propellant accounts for 1.1 million pounds.

ATK Thiokol is the world’s leading supplier of solid-propellant rocket
motors. Products manufactured by the company include propulsion systems for
the Delta, Pegasus®, Taurus®, Athena, H-IIA, and Titan IV B expendable space
launch vehicles, NASA’s Space Shuttle, the Trident II Fleet Ballistic
Missile and the Minuteman III Intercontinental Ballistic Missile, and
ground-based missile defense interceptors.

ATK is a $2.4 billion advanced weapon and space systems company employing
13,100 people in 21 states.