New ‘Rocket Engine of the Future’ goes to ‘Mainstage’

A new rocket propulsion technology demonstration has marked an important milestone, achieving “mainstage” or constant full-power performance for the first time. Called the Integrated Powerhead Demonstration, or IPD, this development project combines the very latest in rocket engine propulsion technologies. To date, the IPD has conducted 21 of 26 tests and accumulated 300 seconds of operation, up to 100 percent power level at NASA’s Stennis Space Center (SSC) in Mississippi.

The IPD is being developed through the combined efforts of Pratt & Whitney Rocketdyne, a business unit of United Technologies Corp. , Aerojet, and NASA’s Stennis Space Center, under program direction by the Air Force Research Laboratory (AFRL) and technical direction of NASA’s Marshall Space Flight Center (MSFC). Its technologies are directed at achieving the goals of the Integrated High Payoff Rocket Propulsion Technology (IHPRPT) program and NASA’s Exploration Technology Development Program (ETDP).

Capable of generating about 250,000 pounds of thrust, the demonstrator uses liquid oxygen and liquid hydrogen in a first U.S. demonstration of a full-flow, staged-combustion (FFSC) cycle. The FFSC cycle uses a fuel-rich pre-burner to drive the fuel turbopump, and an oxidizer-rich pre-burner to drive the oxygen turbopump. Because all of the propellants in the pre-burners are burned, more mass flow is available to drive the turbines than in a conventional staged combustion cycle.

This additional power enables lower turbine temperatures, which translates into longer turbine life, a key factor in reusable engine life. Also, the use of oxidizer-rich gas in the oxidizer turbine and fuel-rich gas in the fuel turbine eliminates the need for a complex propellant seal for the pumps, and means lower risk of leaking liquid fuel into a fuel-rich gas or liquid oxygen into an oxidizer-rich gas, thus increasing engine system reliability. The turbopumps also employ hydrostatic bearings, eliminating wear and enabling high reusability.

Stephen Hanna, Air Force Research Laboratory’s (AFRL) IPD program manager, commented about the technological success and its team. “I can’t tell people how excited I am about this program. Our team, composed of engineers and managers from AFRL, the NASA Marshall Space Flight Center, the NASA Stennis Space Center, Pratt & Whitney Rocketdyne, and Aerojet, is incredibly talented and the best that the industry and government have to offer. The partnership that we have forged among AFRL, NASA and industry is second to none. We continue to pave new technological ground each day, currently developing and test firing the first new liquid rocket engine cycle in the last 35 years. That dates back to the early development days of the Space Shuttle’s Staged-Combustion Main Engine.”

“Our intent is to validate new propulsion technologies that can be used in a new generation of rocket engines,” said Don McAlister, Pratt & Whitney Rocketdyne (PWR) IPD program manager. “The IPD itself will not be flown, but its technologies will find their way into future rocket engines and will be especially valuable for NASA’s Vision for Space Exploration.”

Added PWR President Byron Wood, “The IPD is a critical program that clearly demonstrates how effective NASA, the Air Force and industry can be when they work together for a common objective. That will be increasingly important as we continue to build on America’s leadership in space.”

“Reaching 100 percent power level is a major milestone in testing the IPD engine,” said Stennis Space Center Director Rick Gilbrech. “Technologies developed through the IPD could benefit the Vision for Space Exploration — to return humans to the moon, Mars and beyond. I congratulate the entire IPD team led by the Air Force Research Lab and NASA’s Marshall Space Flight Center and am proud of the Stennis test team for enabling this significant achievement.”

The IPD program is managed out of the Air Force Research Laboratory at Edwards AFB, Calif., with technical support from NASA’s Marshall Space Flight Center. Pratt & Whitney Rocketdyne is the systems integrator and also provides the fuel and oxidizer turbopumps, the main injector, the main combustion chamber, the demonstrator control system and other systems components. Aerojet provides the fuel and oxidizer pre-burners, nozzle, and fuel pre-mixer. Test operations and facilities are provided by NASA SSC.

Pratt & Whitney Rocketdyne, Inc. offers a complete line of propulsion products for launch vehicles to missile defense to advanced hypersonic propulsion. These have been used in a wide variety of government and commercial applications, including the main engines for the space shuttle, Atlas and Delta launch vehicles, and high altitude defense systems. PWR is part of Pratt & Whitney, a world leader in the design, manufacture and service of aircraft engines, space propulsion systems and industrial gas turbines. United Technologies provides high-technology products and services to the aerospace and building industries.