High-Strength, Low-Weight Graphite Composite Case Reaches Key Milestone

A significant milestone in ATK's NASA Research Announcement (NRA) Advanced Booster risk-reduction program for the Space Launch System (SLS) has been reached with the successful completion of filament winding of a pathfinder Advanced Booster composite case. Ultimately, this Advanced Booster NRA effort will enable NASA and ATK to optimize a case design that will be stronger, yet more affordable than traditional steel cases. In turn, this will provide increased payload performance due to reduced weight inherent in composite materials.

"ATK's risk-reduction efforts on this NRA will help NASA with technological development and performance upgrades in the future," said Charlie Precourt, vice president and general manager of ATK's Space Launch division. "It also ties to cost reductions we have made on the existing SLS boosters and advances in our commercial business."

The pathfinder article is a 92-inch-diameter, 27-foot-long composite case. In order to achieve both the affordability and performance required of an Advanced Booster, ATK overcame unique challenges during case winding operations. ATK leveraged 45 years of composite case winding experience, its experienced workforce, and a modern fiber-placement tooling system to achieve success on its first attempt. "Creating a composite case and developing advanced propellant for NASA's advanced booster coincides with technological advances in our commercial rocket programs at ATK," said Precourt. 

ATK has manufactured more than 1,600 commercial solid rocket motors to date, many of which use composite cases and high-energy propellants, for a wide variety of launch vehicles including Delta II and Delta IV, as well as Orbital's Pegasus, Taurus, Minotaur and Antares space launch vehicles. ATK first entered the commercial launch vehicle market in 1987 when it developed its first commercial composite motor, the GEM-40, which is still being used on the Delta II launch vehicle. ATK's commercial product line includes GEM, CASTOR, and Orion solid rocket motors.

The next step in the Advanced Booster NRA program is to continue development of high performance and low-cost propellants that meet the lofty payload and affordability goals of NASA's Space Launch System (SLS). These propellants, many of which are also widely used in ATK commercial solid rocket motors, combined with the achievements made in composite case technology, will provide NASA several options for performance increases for the next generation Advanced Booster.

On the existing SLS boosters ATK's Value Stream Mapping (VSM) process, which is a company-wide business practice, allowed the employees to identify inefficient processes, procedures and requirements to help reach the target condition. Through this process, ATK identified more than 400 changes and improvements, which NASA approved. These changes have reduced assembly time by approximately 46 percent, saving millions of dollars in projected costs for the SLS system.

(Image provided by ATK)

FMI: www.atk.com