High altitude payload design
The mission: During my engineering placement year at Cambridge Consultants, I led a project to design, build, and validate a high-altitude payload for a stratospheric balloon flight. The target altitude was 30 km—the edge of space. Up there, the environment is brutal: the temperature drops to -60°C, and the atmosphere is so thin that convective cooling for electronics practically stops working. My payload needed to protect sensitive computing equipment from impact, extreme cold, and ironically, overheating.
Thermal engineering: To solve the thermal puzzle, I dug into aerospace engineering principles and designed a few conceptual cooling solutions. I built preliminary models in ANSYS to simulate how heat would flow (or fail to flow) away from the critical CPUs in near-vacuum conditions. While simulation is great, the only way to know for sure if a custom heatsink design will work is to freeze it and starve it of air.
Lab validation: I utilized the company's environmental testing facilities, locking the payload in a vacuum chamber that dropped to -40°C. I designed a rigorous test plan that simulated the exact pressure drops, thermal gradients, and flight durations we expected. After dialing in the thermal regulation in the lab, we were cleared for two live flight campaigns in April and May.
Flight results: The data logged from the recovered payload was a massive success. The cooling system kept the CPU temperatures perfectly stable and well below critical throttling thresholds for the entire flight. The onboard camera also captured some stunning images—like the shot on the right, taken at 24 km altitude over Bedford, looking down on a commercial Boeing 777 airliner.
Wrapping it up: I concluded the placement by presenting the journey—from whiteboard concepts to stratospheric flight—to the entire company. I made sure to document every CAD file, parts list, and thermal profile, ensuring the team had a solid, flight-proven platform for future scientific missions.