Please describe an example of a system that you worked on from start to finish that you are most proud of

I was asked this question for a job application. Something hit me and I started to stream our thoughts from my memory to the keyboard. I thought this is a worthwhile story. Just going to paste it below.


I am most proud of my most recent brain-child, Colossus. Colossus is a 5,000 lb-class Dual Cryogenic Rocket Engine Teststand. I was the project manager and chief engineer of Colossus from conception to delivery. From conception to finish, Colossus took 2 years, cost $330,000, and 20,000 man-hours of work. It was one of the most endearing projects any university group has ever attempted, yet we pull it off with flying colors.

The conception of Colossus came after my organization, SEDS UCSD, faced a growth bottbleneck becasue we were not able to test our innovate 3D printed engine designs fast enough, accurate enough. After a fortunate encounter with NASA’s Rocket Propulsion Test Program’s director, we realized that this isn’t just a problem of our own, but rather, a problem faced by almost all University liquid rocketry teams. We realized that building Colossus would not only benefit ourselves, but also countless fellow collegiate rocketeers who will lead the future of space exploration.

After John Marcozzi and Deenah Sanchez laid the ground for Colossus’s framework, I gathered a small team of club members in May 2016 to flesh out the early concept iterations of Colossus, we derived a series of requirements from our past engine testing obstacles. These requirements, which all came true after 2 years of design and build are:

– Must be mobile

– Capable of withstanding 5,000 lbs of thrust with high safety factor

– Must be able to deliver any non-hypergolic cryogenic fuels and oxidizers

– Must be able to gather high fidelity data

– Must have configurable Engine Interface

– Must be able to perform test fully automated

Through this list of requirements are short, achieving all of them with high quality turned out to a way bigger design challenge than we previously thought. I broke the team down into Systems, Electronics, Plumbing, and Structures sub-teams, and worked for months with my team to deliver a early design concept. In September, we were able to come up with a early stage budget, and a complete CAD of the system. We contacted our mentors at NASA again, hoping that our design would impress them and broker a funding grant. However, our first attempt was unsuccessful. NASA sent a team of engineers to San Diego to review our design in October and tore all of our work apart. We were critiqued in every element of the project; our structures design didn’t have FEAs to support our claims, we did not consider transportation vibration, our plumbing sizing was incorrect under cryogenic conditions, and the design had numerous flaws that could lead to catastrophic failure if built as such, out electronics had no redundancies, and no alternative paths to safe state… the list goes on for pages.

After the first defeat, we got right back to work, hoping to deliver a more convincing design next time. I recruited additional members to crank up the increased design workload. I redesigned the electrical system using the industrial standards I’ve just learned working at Tesla’s Fremont Factory. Instead of performing plumbing and fluids calculations by hand, I tasked the team to perform all calcs in MATLAB so that we can repeatedly iterate and validate results, preventing propagated error. We remodeled the structures on a actual 17ft utility trailer, removed all extorted aluminum structural components in our design and replaced them with welted steel to meet the strength requirements. I worked hand-in-hand with the team, solving each team’s technical bottlenecks while balancing a progressing schedule and budget, and managing a team of 30 energetic student engineers.

Four months later, we are back to the conference room with our NASA advisors. This time, with a 200 page design package detailed to the bolt. We not only covered the technicalities of Electrical, Fluids and Structural comments, but also performed extensive Systems Engineering Analysis, producing a System Architecture breakdown, System Requirements Matrix for requirement traceability, Concept of Operation to plan for the operation stage of Colossus, System Engineering Management Plan, Risk Assessment and Mitigations, Transportation Logistics, Safety Plan, Verification and Validation Plan, Standard Operation Procedures, and Work Breakdown Structures. We had a clear idea of what each Document is made for and how to use it to maximize our chance of success. Our freshly redesigned mechanical systems were not only CAD’d in 3D models, but also documented in 2D drawing released in industrial standard, ready to be used in any fabrication shop. Our budget not only grew in price, but also in size, detailing over 3000 different parts to be used for the system. After a lengthy 10 hour Critical Design Review session, answering endless difficult questions, we walked away with a $100,000 check from NASA.

The above discussed design package can be found here (

This is only just the official beginning of Colossus. With our budget costing up to $330,000 we needed more help outside of NASA’s funding to make Colossus a reality. I lead the team into a intense period of sponsorship campaign for in-kind and monetary supports. By the end of the campaign, we were able to cover all the potential cost of the project. We were able to get out Crygonegic pressure tanks fabricated for free, saving nearly $50,000; our Data Acquisition System for free, saving $45,000; and were able to purchase our 6 Cryogenic valves with a huge discount, saving another $50,000.

Throughout the period from March 2017 to April 2018, Colossus gradually took shape, exactly as designed, and came to completion in May 2018. We went through countless technical obstacles during this period, making minor design adjustments for manufacturability, managing long-lead time parts quoting, ordering and delivery, making arrangements to utilize heavy equipments to install our tanks weighting 1,600 lbs. We logged 12,000 man hours of hard work during the construction phase of Colossus. Over the summer of 2017, we lost nearly half of the team due to graduation of seniors, I recruited new members in fall and trained everyone up to speed. We enjoyed weekly break through as Colossus took shape, from seeing the structures completed to getting everyone painted, to installing all the plumbing and electrical components, watching colossus grow is one of the most gratifying experience in my life.

Building Colossus physically was fulfilling, but what was even more fulfilling was building the Colossus team. The team became incredible tight-knit and efficient over the years. At first, I had to use decline and rule to install the core principles of this team, over time, the team became a self-fulfilling prophecy, with members clearly understanding their responsibilities and holding up the trust gifted among the teammates. As our NASA advisor put, “you guys are going to graduate University with 5 years of experience ahead of your peers, you are doing real, meaningful industry work”. Through Colossus, I touched the life of 40, sending top-notch graduates to their dream jobs at SpaceX, Virgin Orbit, Northrop Grumman, Via Sat, Apple, Tesla, NASA, and many other places. Colossus alumni have a 100% employment rate in the industry and are set to become the future leaders of mankind’s endeavor to conquer the cosmos. I could not be prouder of my team.

See footage from Colossus Launch Party here

Colossus Story Video here