The end-all solution to my 2021 summer concerns turned out not to be as trustworthy as I’d expected.
It was around Week 5 of the middle school engineering program I was teaching when I noticed things weren’t quite going to plan, and the issues we were facing stemmed from the very source that had troubled me for much of the summer leading up to it: connecting the wires in the ESCs and brushless fans. I was using exactly the same method that had proved successful for my proof-of-concept hovercraft–stripping part of the silicone casing from the tips of the wires, twisting them together, and capping them with a wire nut–but rather than getting a smooth, steady whir from the thrust and lift fans, all that emerged were erratic sputters and eventually complete stillness.
Obviously, none of the students–I worked with a small class of about 9 engineers–were pleased with this setback. I often heard complaints of “our wires suck!” and “there’s no way we’re winning” while frantically trying to pinpoint the issue and using the few tools I had to fix it. Moreover, as an unruly group of middle school students, they tried improvising solutions themselves with somewhat dangerous equipment: on two occasions, groups attempted to plug the fan’s wires directly into the 11.1mV battery, causing sparks to flare and filling the room with the toxic smell of burnt copper. I soon discovered that these incidents inflicted damage to the fans themselves, rendering them largely non-functional and forcing me to scrap them.
Although the sessions ended at 4:00, I often stayed until 5:30 trying to keep the wires connected and make it so that they wouldn’t become disconnected. But it was all in vain, as when the hovercrafts were given a test run, the wires were jutted out of place.
With my electrician-recommended solution dashed, my hopes were low. The final class–and the day of the big race–was scheduled for March 10th, so I had about two weeks to correct the issues we were having.
Then, a breakthrough: while searching the vast depths of Amazon, I came across another thrust fan–slightly larger and more powerful than the others, but not so much as to give any one team an advantage–that came with pre-soldered bullet-plug connectors on the wires, allowing for a flawless connection with the ports on the ESC. It would require some pretty serious hovercraft surgery and a brand new set of ESCs, but, as the saying goes, it was just crazy enough to work.
A lucky break in my schedule (what I had scheduled to be the last day of the program inadvertently fell on Career Day, and the following two weeks were reserved for spring break) allowed me to take all three of the students’ hovercrafts home with me and make the changes to them that were necessary. Removing the sub-optimal fans and the ESCs they connected to necessitated full-body replacements for all three, but nonetheless, after a weekend of work, the three hovercrafts appeared to be race-ready.
Race day fell on April 1st, the first Friday after break. Our group moved down to the school’s gym, which filled with noise almost instantly as fans were connected and revved to full-throttle. My original plan for this day was as follows:
- A maneuverability contest, in which an obstacle course would be quickly assembled and the three hovercrafts pitted against each other in a time-trial format.
- A drag race, which would function purely as a test of speed and aerodynamic capability.
- A design contest, where the three groups’ hovercrafts would meet the critical eyes of some of the school’s faculty and be placed on how well they fulfill the design criteria.
- A heartwarming message from myself at the end of the day, which would commend them all on the tireless effort and boundless engineering curiosity they demonstrated over the course of the program.
Instead, the day followed these events:
- About 30 minutes of trying to figure out how to actually drive the hovercrafts.
- An accident, which wrecked one of the brand new fans after one of the hovercrafts capsized and necessitated a replacement that would last beyond the time that remained.
- A very informal drag race, in which the winning hovercraft blazed across the ~20-foot distance in about 1 minute.
- A design contest, despite the fact that all three of the hovercrafts looked almost exactly the same.
- All of the students leaving as soon as the festivities were over.
But the most gratifying moment from that day occurred after all of the participants, but one, had left.
After that one hovercraft had tipped over onto its front face at the expense of its thrust fan, the group that had built and was driving that hovercraft was, understandably, extremely discouraged. My role model, Daniel, a Bay Ridge Prep graduate and engineering major at the University of Pennsylvania, had made the trip to New York to watch the final day of the program, and he and I took to replacing the fan with one of the defects using the old wire nut technique; however, instead of wire nuts, he proposed that we used tin foil instead, which would remain secure to the connection and provide a source of insulation and electric conductivity that may spark the fan back to life.
He remained incredibly dedicated to applying this solution and stayed until well after the final class had ended trying to restore the hovercraft’s functionality. In the meantime, I continued to supervise the other groups and oversaw the informal drag race and design contests. Then 4:00pm came, and everyone disappeared.
Everyone, except for Tyler, whom I considered the leader of the team that designed the hovercraft.
Tyler had seemingly lost hope, as he kept prodding Daniel and I to give up on his creation; nonetheless, Daniel made incredible progress, remembering to clean the connection (something I had never considered) before securing it with tin foil and a variety of tapes. Despite his lack of enthusiasm, I suspected that Tyler’s willingness to stick around was driven by a hidden desire within him to see his hovercraft work.
I had also suspected that the replacement fan Daniel and I were attempting to install was broken due to a mechanical issue with the copper coils inside of it. Nonetheless, I helped Daniel connect the fan to the battery via the ESC and secure all of the parts to the body of the hovercraft. Tyler turned on the transmitter, and we held our breaths.
Five beeps, and the fan was alive.
All of our excitement was palpable, but none more so than Tyler’s. Since his had been broken down, we felt obligated to redo his group’s drag race run, and the freshly-revamped Frankenstein hovercraft smashed the previous 1-minute record by 53 seconds.
And with that, the saga of my middle school hovercraft engineering afterschool program was completed. While I am overjoyed that the young engineers I taught got to have a taste of the world of STEM, and that I was able to connect members of my school community through collaborative, project-based learning, I learned two things–the value of determination and persistence, and the importance of continued enthusiasm and hope in the face of a challenge–that I will keep with me forever.