ATK (Alliant Techsystems) said solid propulsion rocket motors
manufactured by two ATK Aerospace Group companies helped launch a Department
of Defense Milstar II communications satellite into orbit from a Lockheed
Martin Titan IV B rocket on Jan. 15.
The successful launch, which took place
at Cape Canaveral Air Force Station, Fla., was the first of several Titan IV B
missions planned in 2002.
The Lockheed Martin-built Milstar constellation of satellites is designed
to provide highly secure jam-resistant communications for military users with
mobile terminals.
The Milstar satellite weighs approximately 10,000 pounds,
requiring a large, heavy-lift launch vehicle like the Titan IV B rocket to
boost it to geosynchronous orbit.
Key to the heavy-lift capability of the Titan IV B vehicle are two Solid
Rocket Motor Upgrade (SRMU) boosters manufactured by ATK Thiokol Propulsion at
its Magna, Utah, production plant.
The boosters, which measure 112 feet in
length and 10.5 feet in diameter, hold nearly 700,000 pounds of propellant and
supply 3.4 million pounds of thrust.
The SRMU boosters have been flying on
Titan IV B missions since 1997.
Additional ATK solid rocket motors were used in booster and stage
separation.
Staging rockets manufactured by ATK Tactical Systems Company at
the Allegany Ballistics Laboratory in Rocket Center, W. Va., safely moved the
spent SRMU boosters away from the launch vehicle.
After the liquid second-stage engine completed its burn, four STAR(TM) 5CB
retrorockets jettisoned the spent second stage from the vehicle.
The STAR
motors are produced by ATK Tactical Systems Company at its manufacturing
facility in Elkton, Md.
The nation’s largest, most powerful expendable launch vehicle, the Titan
IV B is capable of boosting up to 47,800 pounds into low-Earth orbit or more
than 12,700 pounds into geosynchronous orbit 22,300 miles above the Earth.
It
is built by Lockheed Martin Space Systems Company-Astronautics Operations near
Denver, Colo.
ATK is the world’s leading supplier of solid rocket motors, with a product
portfolio that ranges from 3-inch diameter spin motors to the Space Shuttle’s
Reusable Solid Rocket Motors (RSRM), which measure 12 feet in diameter.
ATK is a $2 billion aerospace and defense company with leading positions
in propulsion, composite structures, munitions, and precision capabilities.
The company, which is headquartered in Edina, Minn., employs approximately
11,000 people and has two business groups:
Aerospace and Defense.
ATK news
and information can be found on the Internet at http://www.atk.com