NASA and ATK Successfully Test Five-Segment Solid Rocket Motor

PROMONTORY, Utah -- With a loud roar and mighty column of flame, NASA and ATK Aerospace Systems successfully completed a two-minute,
full-scale test of the largest and most powerful solid rocket motor
designed for flight. The motor is potentially transferable to future
heavy-lift launch vehicle designs.

The stationary firing of the first-stage development solid rocket
motor, dubbed DM-2, was the most heavily instrumented solid rocket
motor test in NASA history. More than 760 instruments measured 53 test objectives.

Prior to the static test, the solid rocket motor was cooled to 40
degrees Fahrenheit to verify the performance of new materials and
assess motor performance at low temperatures during the full-duration
test. Initial test data showed the motor performance met all expectations.

"For every few degrees the temperature rises, solid propellant burns
slightly faster and only through robust ground testing can we
understand how material and motor performance is impacted by
different operating conditions," said Alex Priskos, first stage
manager for Ares Projects at NASA's Marshall Space Flight Center in
Huntsville, Ala. "Ground-testing at temperature extremes pushes this
system to its limits, which advances our understanding of
five-segment solid rocket motor performance."

The first-stage solid rocket motor is designed to generate up to
3.6-million pounds of thrust at launch. Information collected from
this test, together with data from the first development motor test
last year, will be evaluated to better understand the performance and
reliability of the design.

Although similar to the solid rocket boosters that help power the
space shuttle to orbit, the five-segment development motor includes
several upgrades and technology improvements implemented by NASA and
ATK engineers. Motor upgrades from a shuttle booster include the
addition of a fifth segment, a larger nozzle throat, and upgraded
insulation and liner. The motor cases are flight-proven hardware used
on shuttle launches for more than three decades. The cases used in
this ground test have collectively launched 59 previous missions,
including STS-3, the first shuttle flight.

After more testing, the first-stage solid rocket motor will be
certified to fly at temperature ranges between 40-90 degrees
Fahrenheit. The solid rocket motor was built as an element of NASA's
Constellation Program and is managed by the Ares Projects Office at
Marshall. ATK Aerospace Systems, a division of Alliant Techsystems of
Brigham City, Utah, is the prime contractor.

For more information about NASA, visit:

http://www.www.nasa.gov

Source: NASA