By Luis Azuara, May 17, 2022
Cal Poly Pomona’s Undergraduate Missiles, Ballistics, and Rocketry Association successfully fired its first liquid engine on April 30.
Aerospace engineering students James McPherson, Kaitlyn Pitugnarongphor and Jacob Liebgott were able to complete something that has never been done at Cal Poly Pomona within only one year independently.
The original idea of the project began two years ago, but after much prep work, this small group of engineers from UMBRA Propulsion felt like it was time to start working on a liquid rocket engine.
UMBRA is an engineering club on campus with more than 200 official members. The club holds multiple project teams such as NASA Student Launch, Friends of Amateur Rocketry competition, experimental and UMBRA Propulsion — which is the team that designed the liquid engine.
UMBRA Propulsion primarily works with solid propulsion, but after much practice and experience with solid motors, the team felt like it was the right time to step into liquid propulsion.
“We had just won our second Friends of Amateur competition in a row, and it (solid propulsion) just started feeling easy. Our team members under UMBRA propulsion felt like we were just rinsing and repeating the same thing,” said McPherson, chief engineer. “So, our next natural step was to step into liquid propulsion.”
In a solid rocket, powdered fuel and oxidizer are mixed into a solid propellent which is “easy,” according to McPherson. With liquid rockets, there are valves, regulators, release valves, tanks and many parts to consider that go into liquid engines.
Currently, most universities do not have liquid rocket capabilities. The schools that do have liquid rocket capabilities typically have hundreds of thousands to millions of dollars in funding and dedicated lab spaces. The small team were able to develop the engine for the most part in McPherson’s living room.
The goal for this first fire was to get a liquid engine fired. McPherson, Pitugnarongphor and Liebgott wanted to see if they could accomplish something that not many colleges do.
“This whole project acts as a pathfinder to test the feasibility as well as see if we can get funding and lab space to move into liquid propulsion,” said Liebgott, test stand engineer.
With the help and funding from Exquadrum, Inc. McPherson, Pitugnarongphor and Liebgott were able to build the engine from start to finish in only one year.
Exquadrum, Inc is an aerospace and defense company based in Victorville, California. McPherson previously interned for them, and Exquadrum was willing to help with the design of the engine. The company’s contribution was building the thrust chamber. This was a huge contribution, as the thrust is what moves the rocket through the air.
Within one hour, the team of engineers fired the engine. What made this possible was a cart built by Pitugnarongphor. Pitugnarongphor was the build engineer for the project. The cart allowed the team to roll out the engine, bolt it to the test stand and fire it within an hour.
During the hot fire, the liquid engine was able to generate up to 423 pounds of thrust with a chamber pressure of 312 psi. The team had a goal of 400 pounds of thrust.
With this accomplishment, CPP students can see that liquid propulsion is possible.
“Why we fly as students is so different to why SpaceX flies. SpaceX flies because they have customers. We are students, no one is going to pay us for launching stuff, but we still launch stuff because of inspiration,” said McPherson. “With this engine we are competing with the likes of Purdue, USC, UCI, Georgia Tech, etc.”
What this project does is help future engineering students. According to McPherson, CPP now has a product that competes with the works of these prestigious undergraduate collegiate propulsion teams.
For this project, the team received no help or funding from Cal Poly Pomona staff or resources. The project was independently funded, created, and manufactured by the team.
“I’m hoping this accomplishment helps us get more funding because liquid rocketry is the future of rocketry overall,” said UMBRA President and aerospace engineering student, Rochelle Casement.
For more information about UMBRA please visit their website and on Instagram.
Feature image courtsey of UMBRA.
