Press Release

ATK Nozzle for Delta IV Engine Passes Flight Certification Testing

By SpaceRef Editor
October 1, 2001
Filed under , ,

ATK (Alliant Techsystems)
said a rocket nozzle for the Boeing RS-68 engine developed by ATK Thiokol
Propulsion Company, Promontory, Utah, successfully passed a series of four
flight certification tests, clearing the way for production of the nozzle and
its use on the maiden flight of the new Boeing Delta IV launch vehicle in
early 2002.

Designed by the Rocketdyne Propulsion & Power business of Boeing, the
RS-68 engine will provide first-stage propulsion for the Delta IV vehicle.
With 650,000 pounds of thrust, it is the largest liquid-oxygen/liquid-hydrogen
engine in the world and the first large, liquid-fueled rocket engine developed
in the U.S. since the Space Shuttle main engine.
ATK Thiokol Propulsion
Company was awarded a contract in 1998 for engineering and manufacturing
development of the engine’s nozzle.

Two of the nozzle’s flight certification tests simulated the most extreme
mission cycles that could be experienced in flight.
The other two tests
replicated the first two tests at 120 percent of the mission cycle.
The tests
were conducted at NASA’s John C. Stennis Space Center in Bay St. Louis, Miss.

Several new technologies were involved in the design of the composite
nozzle, including proprietary thermal protection material to shield it from
extreme gas temperatures that can exceed 6,000 degrees F.

ATK Thiokol Propulsion Company has been building nozzles for solid
propulsion motors since the late 1950s.
The Boeing RS-68 engine is the first
production application of a nozzle of this type and the first use of the
company’s nozzle technology in a liquid engine application.

ATK is a $1.6 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
9,600 people and has two business segments:
Aerospace and Defense.
ATK news
and information can be found on the Internet at

SpaceRef staff editor.