NASA Thruster Achieves World-Record 5+ Years of Operation

 

A NASA advanced ion propulsion engine has successfully operated for more than 48,000 hours, or 5 and a half years, making it the longest test duration of any type of space propulsion system demonstration project ever.

The thruster was developed under NASA’s Evolutionary Xenon Thruster (NEXT) Project at NASA’s Glenn Research Center in Cleveland. Glenn manufactured the test engine’s core ionization chamber. Aerojet Rocketdyne of Sacramento, Calif., designed and built the ion acceleration assembly. 

The 7-kilowatt class thruster could be used in a wide range of science missions, including deep space missions identified in NASA’s Planetary Science Decadal Survey. 

“The NEXT thruster operated for more than 48,000 hours,” said Michael J. Patterson, principal investigator for NEXT at Glenn. “We will voluntarily terminate this test at the end of this month, with the thruster fully operational. Life and performance have exceeded the requirements for any anticipated science mission.” 

While the Dawn spacecraft is visiting the asteroids Vesta and Ceres, NASA Glenn has been developing the next generation of ion thrusters for future missions. NASA’s Evolutionary Xenon Thruster (NEXT) Project has developed a 7-kilowatt ion thruster that can provide the capabilities needed in the future. 

An ion thruster produces small levels of thrust relative to chemical thrusters, but does so at higher specific impulse (or higher exhaust velocities), which means that an ion thruster has a fuel efficiency of 10-12 times greater than a chemical thruster. The higher the rocket’s specific impulse (fuel efficiency), the farther the spacecraft can go with a given amount of fuel. Given that an ion thruster produces small levels of thrust relative to chemical thrusters, it needs to operate in excess of 10,000 hours to slowly accelerate the spacecraft to speeds necessary to reach the asteroid belt or beyond. 

The NEXT ion thruster has been operated for over 43,000 hours, which for rocket scientists means that the thruster has processed over 770 kilograms of xenon propellant and can provide 30 million-newton-seconds of total impulse to the spacecraft. This demonstrated performance permits future science spacecraft to travel to varied destinations, such as extended tours of multi-asteroids, comets, and outer planets and their moons. 

Image Credit: NASA, Christopher J. Lynch (Wyle Information Systems, LLC)

The NEXT engine is a type of solar electric propulsion in which thruster systems use the electricity generated by the spacecraft’s solar panel to accelerate the xenon propellant to speeds of up to 90,000 mph. This provides a dramatic improvement in performance compared to conventional chemical rocket engines. 

During the endurance test performed in a high vacuum test chamber at Glenn, the engine consumed about 1,918 pounds (870 kilograms) of xenon propellant, providing an amount of total impulse that would take more than 22,000 (10,000 kilograms) of conventional rocket propellant for comparable applications. 

“Aerojet Rocketdyne fully supports NASA’s vision to develop high power solar electric propulsion for future exploration,” said Julie Van Kleeck, Aerojet Rocketdyne’s vice president for space advanced programs. “NASA-developed next generation high power solar electric propulsion systems will enhance our nation’s ability to perform future science and human exploration missions.” 

The NEXT project is a technology development effort led by Glenn to develop a next generation electric propulsion system, including power processing, propellant management and other components. The project, conducted under the In-Space Propulsion Technology Program at Glenn, is managed by NASA’s Science Mission Directorate in Washington. 

Aerojet Rocketdyne provides propulsion expertise for domestic and international markets. For more information about Aerojet Rocketdyne, visit: http://www.Rocket.com

To view the NEXT ion engine in operation, visit: http://go.nasa.gov/16v9y8g

Glenn Mahone
Aerojet Rocketdyne