January 2004

Rocket Science

Understanding the Molecular Mechanisms of AIDS

A Cultural Perspective on Technology

Taking IT to New Levels

High-Tech Mapping of Ancient Sites

Tracing the Paths of Scientific Discovery

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Bryn Mawr College
A newsletter on research, teaching, management, policy making and leadership in Science and Technology

Rocket Science
By Dorothy Wright

In October 1934 Jeannette Ridlon Piccard ’18 piloted a balloon to an altitude of 57,579 feet, becoming the first woman to reach the stratosphere. She and her husband, Jean Felix Piccard, inventor of the plastic film balloon, were inducted into the New Mexico Museum of Space History’s International Space Hall of Fame (www.spacefame.org) for their many accomplishments.

In the succeeding decades, other Mawrters have shared Ridlon Piccard’s passion for the science and technology of flight. Currently among these are Pamela Kay Strong (M.S./Ph.D. equivalent) ’74, Ragini Joshi ’73, Shanti Satyapal ’89 and Susan Keener ’94. Their work represents diverse aspects of aeronautics/astronautics — development of advanced composites for engines and rocket structures; computer modeling of missile, radar and weapons systems; launch analyses for the space shuttle; and satellite ground-control systems.

Lighter, Stronger

Pamela Strong Pamela Kay Strong grew up as a self-described “aerospace brat.” In the 1950s her family lived in Alamogordo, N. M., where her father, W.T. Strong, worked in the missile and space division of Goodyear at Holloman Air Force Base. As a child, she was introduced to many visiting scientists at the family’s home, customarily addressing them as “aunt” or “uncle.” Strong remembers sitting on Albert Einstein’s lap, fascinated with Uncle Albert’s famous hair. When she was five years old, Wernher von Braun helped her build her first rocket out of wood.

“Uncle Wernher asked me how the launch went, and I said, ‘It didn’t go to the moon,’” Strong recalls. “He asked, ‘Well, did you get it off the ground?’ I said, ‘Yes, it went as high as a tree.’ He replied, ‘Then it was a success! I can’t get mine off the ground.’”

It seems only natural that Strong has spent most of her career in the aeronautics and aerospace industries. As a senior advanced composite engineer in the Aircraft Engine Group of General Electric Company in the mid-’80s, Strong was an integral member of the team that established the parameters necessary for consistently manufacturing commercial parts from polyimide (PMR-15) and other aircraft structural composites, which brought about major advances in aircraft performance.

“Before I went to G.E., PMR-15 was a laboratory anomaly,” Strong recalls. “The company could not commercialize it because it did not always work at high operating temperatures. It was a long shot, but we got it to work. Without it, aircraft engines would not be as light as they are now. They would use more fuel, and they would not have as much distance capacity as they do.”

Strong was also responsible for the first successful advanced composite commercial-aircraft-engine guide vane, which saved more than 400 pounds and increased engine efficiency by more than 36 percent, yielding a fuel savings of $120 million per engine over its lifetime.

“When I started at G.E., less than two percent of the typical aircraft engine was manufactured of composites,” Strong says. “About three years later, more than 67 percent was made of composites.”

Since 1987 Strong has worked as a principal engineer in the Material and Process Engineering Department of Boeing IDS, Huntington Beach, Calif. Strong provides technical and design support for nonmetallic manufacturing processes and material parameters used in aircraft and rockets, including the Delta rocket structure and motors, Titan, Space Shuttle Orbiter and International Space Station.

A few years ago, Strong’s team developed a composite fairing, a 96-foot-long satellite housing used in the Delta IV Heavy rocket, and compared it with the existing aluminum fairing. “It took a five-ton crane to move a one-third section of the aluminum fairing across the room,” she says. “But two people were able to pick up and move a one-half section of the composite fairing.”

Strong’s team continues to work toward development of lighter, stronger materials. “Nanotechnology — for example, nanographite filaments — is the next leap,” she says. “I hope to have the privilege to assist in that, but there is less funding of research today than in the past. If you don’t have research, you don’t have a future; you just have a current product.”

Zero Hour

Susan Keener When Susan Keener ’94 read Carl Sagan’s book Contact as a youngster, she decided she wanted to become an astronomer and astronaut. Keener followed a trajectory that took her to Bryn Mawr, where she majored in physics and astronomy, and on for a master’s degree in aeronautical/astronautical engineering.

As an engineer at the Boeing Company in Houston, Keener is part of the Guidance, Navigation & Control and Flight Control Group of Space Shuttle Systems Integration, which analyzes the preflight, launch and postflight performance of the space shuttles.

“About three or four months before the flight, my group analyzes baseline data about engine performance, temperature and wind estimates, simulating trajectory runs to check that we have enough fuel to get us into the desired orbit,” Keener explains. “We also help produce mission-specific initial loads of some of the software parameters on board the space shuttle, including guidance, navigation and control parameters.

“On the day of launch,” Keener continues, “we have experts at the launch site sending up weather balloons, getting wind and temperature data. We do another quick run on performance parameters.”

After the flight, Keener says, “We look at the results of our simulations and compare them with the data from the actual flight.”

Keener’s group participated in the analysis of the Columbia Space Shuttle disaster, but she was not directly involved because she had not worked on the flight. Nevertheless, she says, “it hit all of us hard. The issue that’s been on everyone’s mind since February is how to make human space flight safer.”

The group is also fine-tuning its simulations to improve the efficiency of shuttle flights. “The more accurate our simulations are, the more payload we can get into orbit,” Keener says.

Keener acknowledges the vicarious thrill of a shuttle launch, but she is realistic about her chances of becoming an astronaut. “I would still love to go into space, but I don’t think it's going to happen,” she says. “It comes down to numbers: you may work as an astronaut 10 or 15 years, and out of that maybe get two or three shuttle flights.”

Still, Keener derives satisfaction from helping others achieve the dream. “When I sit back and look at the big picture — the fact that my work supports human beings’ exploration of space — that’s the big reward,” she says.

Ground Control

As a software engineer with master’s degrees in electrical engineering and ocean engineering, Shanti Satyapal ’89 has applied her varied science and technology background to the problems of acoustical material design for underwater applications, satellite ground control and national defense.

Shanti SatyapalFor six years Satyapal worked as a satellite systems engineer at Integral Systems, Inc., Lanham, Md., a satellite command-and-control-software developer. Her responsibilities included system integration, client training and technical support of ISI’s real-time satellite ground control system for commercial, government and international satellite systems, including Loral Skynet, Europestar and the Air Force’s space-based infrared system.

Advances in satellite command-and-control software have kept pace with the growing sophistication of satellites’ fuel, propulsion, and on-board control and monitoring systems. “There are modules in every satellite that send out radio signals in the form of telemetry points, which monitor the satellite’s overall condition,” Satyapal explains.

“Real-time ground-control software receives data from an antenna in the form of packets, which are formatted differently for each spacecraft. Today there is a lot more equipment on satellites, each putting out a different type of data, so the control software has to be more sophisticated.”

In 2001 Satyapal supported the launch of the BSAT2A, a Japanese geosynchronous communications satellite manufactured by Orbital Sciences, Inc. Supporting the staff at Orbital Sciences’ control center in Dulles, Va., she was responsible for continuous monitoring of the satellite’s orbit and attitude during the early launch and transfer orbit phases. “I was there for three or four days on shift with another orbit analyst,” she recalls. “I was in constant contact with other ground sites around the world, analyzing live data feeds to make sure that the satellite was on track.

“It was my first launch,” Satyapal says. “It was stressful, but exciting.”

Currently Satyapal is a research staff member in the operations evaluation division of the Institute for Defense Analyses, a federally funded research-and-development center in Alexandria, Va. IDA was established to assist the office of the secretary of defense, the joint staff, and the unified commands and defense agencies in assessing national security issues.

“Our division evaluates large programs that are going through testing, providing the analysis to determine whether a system is performing according to all of its requirements and whether a program is ready for field testing,” Satyapal explains.

As an engineer who has been involved in every aspect of satellite systems from software development to marketing to client training, Satyapal says Bryn Mawr provided a solid foundation. “I think the diversity of my course work at Bryn Mawr has given me a unique background compared to many other engineers.”

What Ifs

Ragini Joshi ’73 had planned an academic career in mathematics. Today she analyzes missile defense systems as an engineer in the Astrodynamics Group of Aerospace Corporation. A private, nonprofit company, Aerospace operates a federally funded research-and-development center in El Segundo, Calif., for the Department of Defense. The company’s primary customer is the Space and Missile Systems Center of Air Force Space Command.

Through its independent computational analyses, Joshi’s group provides technical information used by the Air Force to evaluate weapons systems. For example, Joshi recently performed an independent analysis of a study of a boost-phase missile-intercept scenario.

Ragini Joshi“Let’s say the ‘bad guys’ are firing a rocket at us,” Joshi explains. “Ideally we would want to intercept their rocket during boost phase, when the odds are higher that it will fall back on their own territory; more important, the warhead will not reach its final target velocity and its final target, and the rocket will not deploy the decoys that are used to confuse the intercepting rocket.

“These are good reasons to want to do boost-phase interception,” Joshi continues. “But this is a difficult problem. Mainly, it has to do with the timeline: boost phase is fairly short. The interceptor must be very fast, and it needs to be in the right place at the right time, so a large number of interceptors must be deployed in space.”

Joshi studies the computations used to estimate the number of space-based interceptors that would be required to achieve a certain level of coverage. She does this through computer modeling, mostly large simulations, which require some 5,000-to-10,000 lines of code. “I look at the trends as we alter the parameters; for example, faster versus slower interceptors, or various radar locations and capabilities.”

The increased power of computing allows Joshi to look at many more trends than was possible when she joined the company in 1985. “I can analyze many more scenarios and, therefore, perform a much more thorough analysis in the same amount of time,” she says. “The trouble is, the demand for data is rising to meet the supply, and that is costly.”

Joshi says Bryn Mawr helped prepare her to meet these demands. “I learned to work alone on difficult problems,” she explains. “After going to Bryn Mawr, I felt, if I could do this, I can do anything!”

Eleven Percent

Women in aerospace engineering are still relatively few and far between. When Strong started at G.E. in 1983, she recalls, “I was the first female engineer they had hired at that location in 57 years.” Soon the company hired nine more women.

At RCA Astro-electronics, Joshi was one of only a few women in 1980, “but the number grew,” she says. “I think there are more women in the field on the West Coast; there are lots of women managers at fairly high levels.”

Satyapal observes, “While I was at ISI from 1996 to 2002, there were quite a few women engineers and women programmers with master’s degrees in software, but they generally did not move up to management.”

As recently as July 2002, Keener was the only woman in her group at Boeing. “Since then three other women have been hired,” she says. “We joke about starting a women’s group!”

Indeed, as of 1999 only 11.5 percent of aerospace engineers were women, and only 10.6 percent of engineers overall were women, according to the Society of Women Engineers (www.societyofwomenengineers.org).

As a teacher, member of numerous professional engineering organizations, and participant in community activities with the Girl Scouts, Strong encourages women and girls to launch careers in science and technology.

“The number of women in science and technology fields should be higher,” Strong maintains. “We should let young women know we can be rocket scientists if we want to be.”

About Our Sources

Ragini Joshi ’73 analyzes missile defense systems as an engineer in the Astrodynamics Group of Aerospace Corporation, which operates a federally funded research-and-development center for the Department of Defense. The company’s primary customer is the Space and Missile Systems Center of Air Force Space Command. She earned a doctoral degree in mathematics from Columbia University.

Susan Keener ’94, an engineer at the Boeing Company in Houston, is part of a team that analyzes the preflight, launch and postflight performance of the space shuttles. She studied mission operations, space-systems engineering, system testing and mathematical methods at Johns Hopkins University and earned her master’s degree in aeronautical/astronautical engineering from the University of Illinois, Urbana-Champaign. As an engineer with United Space Alliance, which manages space-shuttle operations for NASA, she trained as a flight controller for the International Space Station.

Shanti Satyapal ’89 is a member of the research staff at the Institute for Defense Analyses. Formerly she was a satellite-systems engineer at Integral Systems, Inc., a developer of satellite command-and-control software, where she worked on system integration, client training and technical support of ISI’s satellite ground-control system. She earned master’s degrees in ocean engineering at the University of Rhode Island and electrical engineering at Johns Hopkins University.

Pamela Kay Strong (M.S./Ph.D. equivalent) ’74 is a principal engineer in the Material and Process Engineering Department of Boeing IDS, working on nonmetallic manufacturing processes and material parameters used in aircraft and rockets, including the Delta rocket structure and motors, Titan, Space Shuttle Orbiter and International Space Station. Among the awards Strong has earned is Boeing’s 2002 Professional Excellence Award for her role in converting the space-launch vehicles from less than 4 percent to more than 80 percent advanced composites. She is a fellow, member grade, of the Society for Advancement of Materials and Process Engineers, the American Institute of Chemists and the Society of Women Engineers.

Dorothy Wright contributes news and feature articles on science, technology, engineering and general interest topics to a variety of publications, including Civil Engineering and Engineering News Record.

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