Turning It Up To 11
By Benjamin Pope
The air was tight with electricity as we turned the power up little by little. I could feel it in my hair and on my skin. We were building a “lifter” – or more properly, an ionocraft. When you create a high voltage between a wire and a thin sheet of aluminum, you get a tiny breath of wind: the power it takes to boil a kettle can barely lift a gram, but with enough power, MIT scientists have recently built a drone using this propulsion, a plane with no moving parts. We built ours out of a triangle of wire, aluminium foil, and thin sticks of balsa wood, attached by fishing line to the lab bench but ready to fly.
Suddenly our professor burst into the lab, wide-eyed. “Come next door! The other group’s flyback has exploded!” I looked at my lab partner Keaton and we dashed next door to see the damage.
We were spending the gorgeous Berkeley spring shut inside a lab, taking the junior year Basic Semiconductor Circuits course. Our final assessment: make something cool, it doesn’t matter what. Keaton and I were determined to do the best project, which in our minds was not necessarily the most dangerous… but to impress we had to take risks. Another duo had hammered two nails into a piece of wood and made a glittering purple arc of plasma between them. The plasma arc pulsed with the beat of the heavy metal music they fed through it. It was — in Bay Area terminology — hella impressive.
Or it had been a moment ago. Now, we were staring at a mess of burned paper and melted circuitry, where the other team’s flyback transformer had exploded. A flyback is the part of an old boxy television that produces the high voltages that light up the screen. With the aid of a screwdriver, you can take it out and use these same high voltages to rip apart the molecules of the air into a glowing, dangerous, fun plasma – the stuff of lightning – that sparks from high voltage wire to grounded metal. But our friends had pushed theirs too far. In turning up their speaker to 11 they had overcharged the transformer and it had exploded, spreading flame and shrapnel all over their lab bench. They were unhurt, but there was little hope they’d pass the course. Now we were the last ones in the race, and we were going to shine with a flyback project of our own.
The professor took us aside and told us sternly: “I know you are well-prepared and I’m going to give you a chance to keep going. But you have to promise me nothing like that is going to happen to your experiment. One mistake and I’m going to fail you.” With the confidence of youth we made our promises and went back to work.
Minutes later I was tuning the transformer to produce more and more power to propel our little Icarus higher. The lifter was straining against its tethers and glowing purple. I pushed it further, and it hummed and glowed brighter. Further still. Further – and then arcs of lightning flashing along the lifter, leaping to nearby metal, setting fire to the wooden struts. Panic – my partner and I shut down the power, put out the fire, and threw the ruined pieces into a shoebox.
Just then the professor came back in and saw us all packed up. “What’s up?” I remember him saying. “Are you leaving early?” We told him we were done for the day, and he nodded approvingly.
A decade later, an academic myself, I can only imagine the anxiety we must have put our poor professor through. To think of students taking such a risk in my class! But we were experiencing the joy of physics: figuring things out as we went, risking failure for the big reward of making something strange and beautiful.
Benjamin Pope earned his doctorate in astrophysics from the University of Oxford in 2017. He is a NASA Sagan Fellow at NYU in the Center for Cosmology and Particle Physics and the Center for Data Science, where he has not yet set anything on fire.