Our Structures

During the 2022–2023 academic year, our Structures subteam focused on advancing two major composite projects: custom carbon fiber body tubes and carbon fiber airfoil fins. We’ve been refining our fabrication methods and validating performance through rigorous testing and simulation. 

Carbon Fiber Body Tubes

We fabricated multiple 1-inch carbon fiber body tubes, experimenting with different layup and curing methods to optimize strength and consistency. The image shown displays a progression from one of our earliest iterations (right) to our most recent (left).

To validate performance, we conducted crush tests using an Instron machine to determine maximum load. Once we confirmed the strength and repeatability of the tubes, we moved forward with integrating them into flight hardware.


4in Carbon Fiber Body Tube

This image shows a finished 4-inch carbon fiber tube used on our Phoenix V rocket. This is the post-mandrel, pre-sanded state. 

Liquid Nitrogen Release Technique

To remove the tube from the aluminum mandrel, we used a liquid nitrogen release process—submerging the tube and pouring nitrogen inside the core. This rapidly contracts the mandrel and allows the epoxy structure to cleanly release. 

Fiberglass Airfoil Fin Layup

We tested a 3D-printed fin mold lined with fiberglass. Two halves were created and later joined, with extra layers of fiberglass for reinforcement 

Carbon Fiber Airfoil Fin Layup

We tested a vacuum-sealed carbon fiber layup over 3D-printed fin shells. This allowed us to create hollow fins for weight reduction, or insert ribs for structural integrity—tailoring the design to our performance needs. 

Rocket Stability Simulations

Using OpenRocket we perform extensive simulations on the rocket's apogee and stability. Given the fin's impact on the rocket stability, the fin team on structures spends a lot of time running various simulations to determine the best fin shape for an ideal apogee and stability. The image to the left is an example of a stability curve for our Phoenix V rocket where our stability off the rail was about 2.2 cal.

Phoenix IV Fiberglass Fins

The image to the left is the CAD of the fins (without the fin tab) that were flown on our Phoenix IV rocket. We did extensive research and testing to determine the ideal fin shape to fly on our rocket. We determined a clipped delta shape would best fit our requirements. We then ran more simulations to dial in the exact dimensions and then sent the fins out to be waterjetted.