Megan Boaman Dixon, EG ’02
An engineering major, Megan Dixon worked as a summer intern at ILC and was offered a full-time job with the company while still a senior.
It took her more than six months to find out if her biggest work project was a success.
Why the long wait? Well, that's the time it took for the two NASA Mars rovers named Spirit and Opportunity to reach the Red Planet—where, upon landing, they deployed airbags that Dixon and a team of engineers at ILC Dover helped design.
Spirit touched down on Mars—sometimes called the "Death Planet" because of its challenging environment — on Jan. 3 and Opportunity reached Mars Jan. 24. Both six-wheel Mars rovers plunged through the Martian atmosphere at 12,300 mph, plummeting to the rocky surface 80 miles below and deploying a set of airbags (each weighing half a ton) just eight seconds before hitting the ground.
The final six minutes of the 300-million-mile journey was the most treacherous for the rovers—between the tight time-frame to slow the spacecraft and the fact that it can bounce upon landing as high as a four-story building and continue to bounce, perhaps 30 times in all, before coming to a stop.
No wonder, then, that Spirit and Opportunity became only the fourth and fifth U.S. spacecraft to survive landing on Mars. More than 20 other spacecraft from various nations have failed to successfully reach the planet, including the British Beagle 2 Lander, which has not been heard from since it was to have landed Christmas day.
Part of the difficulty in reaching Mars is that the rovers must target a very precise spot to land. Adjustments to their flight paths can be made along the way, but a small trajectory error can result in a big detour, or even missing the planet entirely. And, then, of course, there's that bouncy landing.
Playing a part in such an important space program has proved challenging and fulfilling to Dixon, a Dover, Del., native who knew before coming to the University that a career in engineering was in her future.
"I grew up originally thinking I'd be a physical therapist, but when I got to high school, I wasn't thrilled with biology," she recalls. Her soccer coach—then an engineer at DuPont—offered to show her around the plant during a "Take Your Daughter To Work Day" event when she was a sophomore. She was intrigued by the type of work done there and started thinking about a career in engineering. The idea was cemented during her senior year in high school when Dixon shadowed an engineer for a day at ILC Dover Inc.—where she works today.
The daughter of Double Dels Martin Boaman, BE '76, and Elizabeth Bole Boaman, CHEP '77, Dixon says she chose UD because of its impressive engineering program. The University, she says, "exceeded all my expectations. I totally loved it."
It also helped prepare Dixon for the summer internships at ILC she took all through college. The company is considered a world leader in engineered soft goods, with a focus on aerospace products, including airbags for the Mars explorers and space suits for both Apollo and space shuttle astronauts.
Dixon, who is a softgoods design engineer with ILC, was offered a full-time job with the company while still a senior at Delaware. She started in the position just one month after graduation.
"I work with a lot of fabrics, films and flexible materials and design for different applications, such as the impact bags for the Mars probe," she says. ILC created the Mars Pathfinder inflatable airbag landing system first used in 1997. The firm was later asked by the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., to work on airbags for the two $820 million NASA Mars Lander missions. The two rovers have a common goal on their 90-day missions: to explore the Red Planet's surface in search of evidence that the now-cold and dry Mars was once a more hospitable planet.
"If you look at the pictures from Mars, you can see that it looks like there was water at one point in time. There appear to be river beds," Dixon says. "The goal is to have the rovers explore to see to if there actually was water on Mars, which you must have to sustain life forms."
Work on this latest airbag design took about three years and involved a team of ILC engineers, including Dixon. The lead engineer, and Dixon's boss, is fellow UD graduate Jim Stein, EG '92. The current airbag design was based on the Pathfinder, with modifications. The Mars landers use four airbags-each consisting of six intersecting spheres. The woven airbag fabric is Vectran, a liquid crystal polymer fabric with the strength of a bulletproof vest. The airbags, which are designed to withstand both the initial impact and numerous bounces across Mars' rocky surface, are inflated within 1.5 seconds by gas generators.
"We did a tremendous amount of drop testing, about 60 tests in all, from the winter of 2001 through the summer of 2003 at the Ohio-based NASA Plum Brook Station," Dixon says. "We needed to make sure the airbags could survive if the spacecraft lands at different angles, if they hit different size rocks...you name it."
Using a large vacuum chamber, complete with a mock-up lander, the testing—which required ILC engineers to be at the NASA site for weeks or months at a time—was extensive and proved vital in final design of the airbags.
"There was a lot of design trial-and-error, but we think we got it right," Dixon says, adding that "forensic engineering" was conducted on damaged airbags to work out "ways to prevent that damage from ever happening again."
"I did a lot of hands-on work with this project. I was out there for the part of the testing in the vacuum chamber, and I got to install the tendons and the retraction cords inside and outside the bags," she says. "I don't mind computer work, but I love to try and to do things—to really get involved on the ground level."
ILC also designed and built the fabric portion of the egress ramps for the Mars rover (JPL built and designed the hardware). These ramps are what the rover drives down to get off the lander and begin exploring the planet.
Megan and her husband, Millard Dixon III, flew to Florida in June in hopes of seeing the Air Force Delta II rocket carrying the Spirit rover launch from Cape Canaveral. But, the launch was delayed because of weather, and the Dixons returned home before liftoff.
"There were five other people who worked on the project who also made the trip down to see the launch, and all of us missed it except for one. Still, I was glad to have gone. Being there, you knew you were part of something important," Dixon says.
ILC now has Dixon hard at work on a new project—helping create an inflatable hatchway for a government submarine.
"In this job, there's a lot of creativity and problem-solving involved and I love that," she says. "Plus, there's great teamwork. I feel very lucky to be doing what I'm doing."
published 2004 in UD Messenger