To the untrained eye, the hypersonics test bay in Ronkonkoma, New York, looks like a maze of interconnected pipes, valves and hoses. Fortunately, Missile Products Technician Dan Folks, who started his career as a plumber, has a very trained eye. When he joined Northrop Grumman in 2020, Dan discovered his knowledge of moving water, steam and gas through pressurized systems translated perfectly to hypersonics testing.

During a hypersonics test, fuel, oxygen and nitrogen travel through hundreds of tubes into a test bay that simulates hypersonic conditions — meaning, wind speeds of Mach 5 and above — to measure how a product or material performs.

Follow along with Dan on a typical test day.

5 a.m. Mornings can be a little hectic. I wake up early to take out my dog, a mini goldendoodle, before making coffee. By then, my wife is up, and we’ll wake up our two kids around 6 a.m. before I leave for work.

7:30 a.m. I get settled in the test bay, checking emails before heading to our daily site standup meeting. It’s important we’re all aware of planned testing because, during tests, huge portions of the facility become off-limits when we turn on the red light — literally, a bright red light that indicates active testing.

8 a.m. Next, the test team meets to review the checklist, our step-by-step testing procedure. The checklist length varies because every program and test bay have specific needs; our current checklist, for testing the Hypersonic Attack Cruise Missile, has 850 lines.

9 a.m. We begin by validating that the facility is in a safe state, talking to other technicians to make sure they’re not working on anything that might impact our test and confirming that all systems are turned off.

10 a.m. With the facility secured, I hand the checklist to the test engineer, who executes the dry sequence. In this 20-minute practice test, the computer runs the sequence, but nothing physically happens. The data tells us if we need to make any changes before proceeding.

10:30 a.m. We break for lunch while the engineers review dry sequence data. I typically pack whatever I had for dinner the night before; today, it’s tacos.

10:45 a.m. The red light goes on, and we shift into a testing state. There’s a lot of steps to prepare the test bay — many things must come together just right, and the order in which we do things matters. There are hundreds of valves to check and several systems to slowly pressurize. My knowledge as a plumber has been fundamental to my success in this role because much of our facility is reliant upon plumbing.

12:30 p.m. In the control room, I pass the checklist to the test engineer. He reads each command to me, I read it back and then execute the command. This is a safeguard; if he reads it incorrectly, I can question him, and vice versa. We go system by system, bringing each online and up to pressure.

1:28 p.m. The test engineer executes the test sequence. The actual test is short — anywhere from 45 seconds to two minutes. While it’s a lot of work for a short test, it’s very gratifying.

1:30 p.m. With the test done, we de-pressurize the systems from the control room, then begin securing the facility again.

2:30 p.m. Once all clear, we turn off the red light and begin post-test inspections. Using photo and video, another technician and I document any changes to the product or material we’re testing, ensuring everything still functions as intended.

4:30 p.m. We clean up; post-inspection takes about five hours, so we’ll continue tomorrow. I find my job really interesting. Even though we’re testing the same thing each day, every test is a little different — there’s no monotony.

5 p.m. We close the test cabin, do our timecards and head out. I’m headed to Suffolk Community College, where I take mechanical engineering classes twice a week. I’ve always been fascinated with how and why things work, and my time at Northrop Grumman solidified my desire to become a mechanical engineer. Right now, I’m taking a lot of math — calculus and differential equations — and I’ve witnessed the real-life applications at work, which helps my learning process. As an experimental test lab, we’re pushing the limits and I feel lucky to be able to do a job like this.

*Jarrod Krull contributed to this story.