Students in Aerospace Engineering Department at Cal State Long Beach Help Launch 1st Known Flight Test of Liquid-Propellant Powered Aerospike Engine

Students from the Mechanical and Aerospace Engineering Department at California State University, Long Beach were among the members of a joint academic/industry team that recently conducted the first-known flight test of a liquid-propellant powered aerospike rocket engine.

Under the guidance of Eric Besnard, an assistant professor of mechanical and aerospace engineering, Cal State Long Beach students designed and developed the aerospike engine as part of the university’s California Launch Vehicle Education Initiative (CALVEIN), a partnership program with the Garvey Spacecraft Corporation that is directed by Besnard.

The aerospike engine was attached to CSULB’s Prospector 2 (P-2) research vehicle, and the CALVEIN partners got together for a launch at the Mojave Test Area, which is owned and operated by the non-profit Reaction Research Society.

“We are extremely satisfied with the initial results of the Prospector 2 aerospike flight test,” Besnard said. “Our primary objective was to take off and be the first to fly a liquid aerospike, and we did that. We believe that our success in achieving this goal represents a small but important step in validating such engine technology for future reusable launch systems.”

According to Besnard, aerospike engines are better than the conventional bell-shaped nozzles, such as those found on the Space Shuttle, because they offer altitude compensation capabilities. Basically, he said, aerospike engines allow for an improved thrust co-efficient as the vehicle climbs through the atmosphere.
“Conventional bell-shaped nozzles are designed for a specific altitude. Aerospike engines would allow improved performance at altitudes below what the nozzle has been designed for,” Besnard explained.
“Aerospike engines were considered for the Space Shuttle back in the 1960s, but they were deemed too
immature at the time. So, they went with the three bell-shaped nozzles.”

The primary advantage of the aerospike engine, he added, is if you have a vehicle that is going to operate from sea level all the way into space, then there is a performance advantage to using the aerospike engine. Right now, however, NASA is looking at two-stage vehicles. Using the aerospike is not as beneficial for such launch systems.

While the launch was a success, the flight of the vehicle was short-lived. Several seconds after entering stable flight, the P-2 abruptly pitched 90 degrees and demonstrated unstable operation until finally transitioning into a terminal descent and crashing into the desert floor.

“When we re-did the new engine for the flight, there was a small difference in the way a part was inserted, and there was a little gap that shouldn’t have been there. That gap created the problem we observed in the flight,” Besnard said. “Afterward, we were able to look at the engine, and it didn’t get damaged from the crash at all. The anomaly was clearly visible.”

Besnard said from an educational standpoint, the malfunction after the launch is really beneficial for the students because not only did they build and test the engine and see why it didn’t operate properly, now they are able to go back and fix it and try it a second time.

“We have already identified several areas for improving the basic aerospike engine design. At the post-flight data review, we will collect any other lessons-learned from the flight test and will update our near-term flight test plans,” John Garvey of Garvey Spacecraft Corporation noted. “The key for us is to keep conducting these flights in combination with incremental improvements.”

And Besnard and his students are happy to be a part of the process. “From a broader perspective, this kind of hardware-based research and development, which has depended heavily on student contributions, is essential for preparing tomorrow’s aerospace engineers who will be developing such vehicles.”

Media Contacts: Rick Gloady, 562/985-5454, rgloady@csulb.edu
Shayne Schroeder, 562/985-1727, schroede@csulb.edu