Air Force Research Laboratory launches new age in testing

Published Sept. 13, 2010
By Kenji Thuloweit
95th Air Base Wing Public Affairs

EDWARDS AIR FORCE BASE, Calif. -- Air Force Research Laboratory Detachment 7 here began a new phase of rocket testing with the delivery of an Upper Stage Engine Technology program turbo pump Sept. 8, 2010.

The pump was delivered to AFRL's upgraded 2A rocket test stand, where it will undergo a series of tests using liquid hydrogen.

The turbo pump essentially drives a liquid rocket engine. Once installed on a rocket engine, the pump pulls the propellants down from the storage tanks so they can react and produce thrust, propelling the upper stage of a rocket into space after the lower stage booster runs out and drops off.

"It looks pretty small, but it is about 4,000 horsepower," said Shawn Phillips, AFRL Space and Missile Propulsion Division deputy chief. "This is a key component and probably one of the most technically challenging components within a liquid rocket engine. This turbo pump is a typical one that you would see on an upper stage engine that would launch us into space."

The testing of the USET turbo pump represents a paradigm shift in the way rocket testing will be conducted. In the past, AFRL would sometimes test completely built rocket engines and components and hope the data collected would be sufficient. Sometimes the engines would explode during testing.

"What we're doing is taking the 'build them and bust them' days of rocket testing and moving it into heavy integration and modeling simulation," Mr. Phillips said. "With this pump, we would see anywhere from 700 to 3,000 tests done on a rocket engine and now we are looking at an order of 20 to 50 tests on a rocket engine before we move into an acquisition program."

With present technology, smaller components of rocket engines can be tested with the help of computer design software and are heavily instrumented to collect data more efficiently.

For testing, the turbo pump will sit in a 'test skid' container and will be connected to more than 135 instruments to collect data. Liquid hydrogen will be fed through the pump to see how it performs once attached to the test stand equipment.

"The purpose of the USET program is to modernize upper stage engine components with modern manufacturing techniques and design methods," said Alan Sutton, AFRL USET program manager. "The original upper stage engines operating today were designed in the 50s and 60s with drawings and slide rules, so we are taking advantage of computer designs and manufacturing in order to create a new modern upper stage engine."

Mr. Phillips said AFRL's product is data.

"What we're trying to do is understand everything we can about the turbo pump and liquid rocket engines so we can design better ones in the future and also hand that technology information off to someone like the Space and Missile System Center and Air Force Space Command," said Mr. Phillips.

The delivery of the USET turbo pump represents a milestone in the program.

"I've been working on the USET program since 2004 when it started out as a paper notion," said Mr. Sutton. "Since it's a unique one-of-its-kind hardware, the design and fabrication have taken years. This test is the culmination of and verification that all the work we have done over those years is working exactly the way we have planned."

The Air Force operates the Evolved Expendable Launch Vehicle system, which is a family of launch vehicles that sends all Department of Defense satellites into space. The USET program is providing technology to eventually upgrade and improve the upper stage portion of the EELV system.

The USET program's specific goal is to develop and test-validate a new set of liquid rocket engine design software tools. The USET design tools are a revolutionary change in the way that rockets are developed. The USET tools can be applied to not only upper stages, but boosters as well.

USET is being funded and directed by the Integrated High Payoff Rocket Propulsion Technology initiative. The goal of IHPRPT, a multi-agency national rocket propulsion technology planning program, is to double U.S. rocket propulsion capability. USET and other IHPRPT programs have been established to develop the technology for existing and future systems to reduce launch costs while increasing payload to orbit and increasing reliability of rocket propulsion systems.