Have you ever wondered what it would be like to be a "rocket scientist"? Home Science Tools interviewed John Anderes, an aerospace engineer since 1965, about his job working on dozens of satellites and America's first space station, SkyLab.
HST: When did you decide you wanted to work in aerospace engineering?
John: I actually entered college expecting to be a chemical engineer. However, after two years of inorganic and organic chemistry (seems like I blew up almost every experiment in the lab), I was ready for something else. I leaned towards subjects I enjoyed the most, applied math and physics. The University of Wisconsin had just created a new BS degree in Applied Mathematics and Engineering Physics, and it was a perfect fit.
HST: Did you like science and math when you were in school?
John: I really became interested in math and science in ninth grade, when I had a great math teacher - Ms. Hawker - and a great science teacher - Mr. Kiss. They made math and science come alive. Excellent teachers probably have no idea how much they can affect the lives of their students, but I am truly grateful to them.
HST: What was your favorite part of your job?
John: I've worked over the last 40 years in many different areas of the aerospace industry. By far, the most fun for me was in modeling and simulation: developing launch, on-orbit and even landing models of space vehicles and satellites.
Simulations, depending on their goals, require knowledge in almost all aspects of aerospace engineering including structural, thermal, controls, propulsion, programming, optics, aerodynamics, astrophysics, and so forth. In the early years, simulations were developed by programming the laws of physics using the programming language Fortran. For example, my first job entailed simulating the motion of a Titan IIIC launch vehicle from liftoff to satellite orbit insertion. The goal was to model the physical rocket motions as forces were applied to it from its engines, aerodynamics, stage separations, and payload ejection while at the same time being controlled by the onboard computer program to fly the appropriate trajectory so that the satellite was placed in its proper orbit. This was done with the goal of checking out the onboard flight control system.
(John's simulations made sure a satellite could withstand all the stress put on it in different phases of its life cycle (e.g., launch, orbit, or even emergency landing for satellites that were carried on the Space Shuttle). He determined the maximum load the satellite could take, and then his calculations were used in the laboratory where the satellite was tested on shaker tables and in thermal, vacuum, and acoustic chambers.)
HST: What kinds of satellites did you work on in your career?
John: My first job involved performing launch and on-orbit simulations of the VELA satellite used to monitor Russia for nuclear test detection. After that I worked on the SkyLab space station, and then literally dozens of NASA satellites launched on an assortment of launch vehicles, including Delta, Atlas, Pegasus and the Space Shuttle.
HST: What is the biggest project you have ever worked on?
John: The biggest project that I personally had to do involved the development of an on-orbit simulation of the SkyLab space station to determine the structural loads on the spinning space station when it maneuvered its large solar panels to point to the sun. I and another engineer were the only ones actually working on the task and the pressure to finish on time was very great. I distinctly remember kneeling and praying by the computer as the last simulation tests were being completed. God answered.
HST: About how long does it take to design, build, and launch a satellite?
John: For satellites, the development time can greatly vary depending upon complexity of the mission. The large NASA satellites such as HST (Hubble Space Telescope), UARS (Upper Atmosphere Research Satellite), GRO (Gamma Ray Observatory), Galileo, and JWST (James Webb Space Telescope) can easily take upwards of 10 years from conception to launch. On the other hand, my former company is currently building for the Air Force a developmental satellite, TacSat III, which can be launched within a year to provide needed surveillance for our armed forces.
HST: What kind of computers did you use in the 60s?
John: Believe it or not, we did have computers in the 60s, but mainframes were all there were. No desktops, laptops or even electronic calculators. Data was entered into the computer via punched cards or magnetic tapes, both programs and input data. Output was mostly on reams of computer paper and magnetic tape, but some data could be dumped and then viewed on black and white CRT monitors. Even in the late 60s (Apollo landing era), I had to check the computer calculations via slide rule and large mechanical Friden calculators — Fridens could actually do square roots. I often hand plotted data on graph paper to more easily visualize results and trends.
HST: How did technological advances change your job?
John: Of course, many technological advances were created by the aerospace industry itself. Just think of what your world today would be like if there were no satellites used for weather prediction, Direct TV, cell phones, and so forth. Personally, changes in the computer take the prize. From creating your own programs on punched cards and hand plotting on graph paper to creating three dimensional models that look like photographic pictures, running commercial software, and viewing the results via color 3D movies is a huge change. But in some ways, working in this new environment an engineer can lose perspective of the basics of the problem he's solving and too easily believe what he's seeing on the computer screen. One really needs to understand the limitations of the software being used.
HST: What do you think are the most interesting events in the aerospace industry?
John: I love astronomy, so the Hubble Space Telescope has to be top dog satellite in my book. Its reach into the heavens has been almost overwhelming even to ardent astronomers. The Galileo mission was so important for viewing Jupiter and its active moons.
HST: What do you remember about the Apollo 11 moon landing?
John: It was a very exciting time. I worked for the company that built the guidance systems for Apollo. I remember very distinctly watching the event on TV with my wife. It was night time and she was feeding our second just-born child. I took a black and white fuzzy picture with our camera of the TV screen.
HST: Do you have any advice for someone who wants to become an aerospace engineer?
John: Enjoying science, math, physics and engineering goes a long way. Engineering requires logical and creative thinking; that's what makes it so much fun. It is really great to be part of our expansion into the heavens. Practically, when in college, taking a semester to co-op at NASA or in an aerospace firm is very beneficial.