Olympus

Olympus is an 11.2 foot long, 5 inch diameter rocket designed and simulated to reach Mach 2.2 and a 30,000 foot apogee. It was LRA's entry for the 2025 International Rocket Engineering Competition (IREC), where we meet with and compete against hundreds of universities to advance amateur rocketry globally.

The Goal

In 2025, we sought out to achieve many goals. Broadly, we sought to perform well in the 30,000 foot commercial motor category. Specifically, we hoped to improve a few key things from the previous year's rocket, Triton. We wanted to focus on more accurate mass budgeting, developing more accurate simulations, and optimizing our rocket for the supersonic speeds and high altitude it would experience. The way we achieved these goals will be outlined in the process section of this page.

The Process

Over the course of our year-long design and manufacturing process, I worked hands-on on essentially every inch of the rocket. In this section, I'll highlight my key contributions.

Airframe Integration & Fin Assembly

The primary structure of Olympus consisted of a fiberglass airframe paired with carbon-fiber fin structures designed for sustained transonic and supersonic flight. I was responsible for fabricating and integrating these components into the final flight vehicle.

For the airframe, there was a large focus placed on precise surface preparation and bonding to ensure structural continuity across coupling sections and other load-bearing interfaces. Since the vehicle was meant to reach over Mach 2, minimizing geometric imperfections was critical to prevent significant asymmetric loading and excessive aerodynamic drag.

The fin system was constructed with G10 fiberglass and reinforced with a wet carbon-fiber layup to maximize stiffness-to-weight ratio and reduce fin flutter at high dynamic pressures. Special care was taken when attaching the fins to ensure symmetry and accurate cant angles. Epoxy bonding procedures were controlled to ensure adequate fillet geometry and load distribution at fin roots. Each fin was laid up with careful attention to fiber orientation and bonding surfaces to ensure load transfer into the fin can. Since fin root stresses increase significantly at supersonic speeds due to aerodynamic loading and shock interactions, proper structural reinforcement was essential.

This fabrication and integration phase established the structural foundation that would ensure survivability under high-Mach conditions.

Aft Boattail Aerodynamic Optimization

To reduce base drag and improve high-speed performance, a small team CADed, manufactured, evaluated, and iterated eight distinct boattail geometries.

Each boattail configuration varied in taper angle, length, and exit diameter. These directly influenced pressure recovery in the wake region and affected both drag coefficient and our static stability margin. We found that while more aggressive tapers reduced base drag, they also shifted the center of pressure forward thus altering the vehicle's stability characteristics.

For each iteration, we evaluated predicted apogee and stability margin using one of our flight simulation tools, OpenRocket. This required striking a balance between multiple competing constraints:

• Minimizing base drag at supersonic speeds
• Maintaining reasonable stability margin
• Preserving manufacturability and structural integrity
• Ensuring compatibility with our motor retention system

Through this iterative process, we identified a geometry that provided meaningful altitude gains without compromising stability or introducing complexity in the structure or manufacturing of the part. The final configuration reflected how small geometric changes at the aft end of a flight vehicle can disproportionately influence overall performance.

The Outcome

Ultimately, our flight ended up failing at around 16,000 feet and just over Mach 1. So why put this in my portfolio? The lessons we learned are integral to the development of our current rocket Aurora and my personal rocket, Razzmatazz (I know it's an awesome name. Don't worry, more info coming soon). We were ultimately not able to recover the booster section of our rocket, so the exact failure mode is unknown. In the next section, I'll cover the possible conclusions we came to.

Post Flight Analysis & What We Learned

There were 3 potential ways in which we assume the rocket may have failed, and I'll list them in order of most to least likely.

1. The motor itself failed.

We think this is the most likely cause of failure. Our rocket passed 3 detailed safety and flight inspections before Olympus was allowed to be vertical on the pad. The failure occurred at the instant the motor stopped burning, transitioning from a normal flight to a small explosion that essentially folded our rocket in half. Beyond this, nearly 50% of the teams who flew on the same motor as us experienced very similar failures.

2. The rocket was not perfectly straight.

After inspecting the body section of our rocket, we saw that the rocket separated at a coupling section. Since the failure occurred just as we passed Mach 1, this possibly indicates that the aerodynamic forces were concentrated at a small bend in the rocket, thus leading to its "folding".

3. One of the fins came off during flight.

Since we were unable to recover the booster section, this possibility cannot be entirely ruled out. If a fin came off or broke during flight, it could have caused a rapid change in direction and reduction of stability that would lead to the failure we saw. However, we think this cause is incredibly unlikely as we spent a long time assembling our fins in such a way that a failure like this is nearly impossible. Beyond this, we performed extensive testing on the fin root strength and the shear modulus of the fins themselves which showed that we were well within safe margins for both.

Despite our confidence that the first guess is in fact the reason for failure, we can (and are) using these failure points to improve the manufacturing of our current rocket, Aurora, by taking more steps to ensure a perfectly straight rocket and more carefully testing fin strength.

As the incoming Manufacturing Lead of LRA's competition rocket for 2026-2027, these uncertainties are fundamentally problematic, and a core focus will be on reducing them as much as possible. As our team moves forward each year, so must our manufacturing methods. Failures happen, but it is our team's and my responsibility to mitigate them with systemic and robustly tested design and manufacturing methods. So now, we're onto Aurora.