The Columbia Disaster: What went wrong?

On the evening of Feb. 1, 2003, as the space shuttle Columbia lay on the ground in more than 84,000 pieces across two states, and seven families mourned the deaths of their loved ones, stunned people around the world wondered: What went wrong?

In the months leading up to NASA's first scheduled space shuttle launch since the Columbia disaster, a class of 15 Lehigh seniors became the only undergraduate students in the world to assume the solemn task of analyzing debris from the tragedy.
Several months after the crash, NASA investigators discovered what caused it: a piece of insulating foam that spalled, or broke away, from the fuel tank during launch and struck the shuttle's wing panel. The impact damaged the panel's thermal protection system, exposing the panel to deadly heat when the shuttle reentered the Earth's atmosphere.
But according to Arnold Marder, the R.D. Stout Distinguished Professor of Materials Science and Engineering, there may be much more to it. How do materials behave under conditions of hypersonic reentry? asks Marder. We had the opportunity to analyze technology that was developed in the '70s and how it responded to a very unusual situation. Future spaceflight may never see this situation again.
Marder and the students in his failure analysis class analyzed pieces of Columbia debris last semester and presented their findings to NASA on April 12 and 14, which included suggestions for building future spacecrafts. NASA was pleased with the results.
The students were able to give us information for the parts we didn't get a chance to study that will certainly be applied or compared to what we have and put toward future generations of vehicles, says Steve McDaniels, chief of NASA's Failure Analysis and Materials Evaluation Branch. We're looking to go to the moon again and on to Mars, and there's always room for lessons learned and new information.
NASA's decision to send pieces of the Columbia debris to Lehigh for analysis also placed the university in the national spotlight. More than 100 news outlets across the country covered the story, including CNN Headline News, Fox News, the Associated Press, Los Angeles Times, Washington Post, and Newsday.


Clues to a tragedy

Each year, students in Marder's failure analysis course peer through microscopes to learn the variety of ways in which different materials -- usually everyday items such as pieces of machines or gym equipment that have been damaged in real-life situations -- deform and crack.
But there was nothing everyday about the materials they worked with this year, as NASA and the Kennedy Space Center entrusted the students with the sobering responsibility of analyzing 50 pieces of Columbia, ranging from windshield to wing.
During a sabbatical with NASA in the spring of 2004, Marder proposed that students in his failure analysis class be given the chance to analyze the debris. Impressed with Marder's work on several projects, including NASA's Return to Flight Program on the Columbia accident, the space agency entrusted him with the project.
Lehigh's materials science and engineering department is an ideal site for such a post-mortem, Marder says. The department is one of the few in the country that offers a failure analysis course, and its microscopy facilities are unrivaled.
Bags containing 50 pieces of the shuttle arrived at Lehigh in early February. When I first saw the debris, I was overwhelmed and the students appeared to be in shock, Marder recalls. They were completely awed by the concept of doing something so important, something for which the seven astronauts gave up their lives.
Each of the 15 students in the failure analysis class was given a piece of the shuttle to study, photograph, cut, grind, polish, and examine under a microscope to determine how the material reacted to the extreme temperatures and conditions.
The project was sort of like forensics -- like CSI Miami. We looked for clues, and a lot of those clues were on the fractured surfaces of the materials, says Ryan Deacon, a Ph.D. candidate in materials science and engineering and the graduate student Marder selected to be the teaching assistant for the class.
With the help of Lehigh research scientist Arlan Benscoter, a world-renowned metallographer, the seniors looked at their pieces under powerful electron and light microscopes to determine how they reacted under the extreme forces and temperatures, as well as why and when the parts stopped working.
The students dug for information on how hot the pieces got and whether they broke quickly like a plate dropping from the counter or slowly like silly putty pulling apart, Deacon says.
Kandice Cohen, a materials science and engineering major, analyzed a piece of the Columbia's windshield and ultimately determined that -- because of the particle impact zones she discovered on the piece while examining it under the scanning electron microscope -- the part fractured during reentry from the blast, not when it hit the ground.
A lot of the pieces of tile [which protect the underside of the shuttle from the heat of reentry] showed failure from a process of heating from the inside, for example, Deacon says. We saw some really interesting material properties coming out of these pieces, and that was NASA's reason for giving us the project -- so we can learn more.
Marder concurs. We've learned how parts fail, and you always make better parts by learning how they fail. This is why automobile companies run their cars into barriers to see if they're crash-worthy. I hope NASA never sees another crash, but we can know that we gave them information that will help them design better materials for the future.
For example, the aluminum used in the shuttle could be improved in the future. The aluminum of the '70s had stuff in it that didn't belong, he says. Marder, however, is quick to add that Columbia's aluminum skeleton was not unsafe; no manmade material could likely have withstood the extreme forces at work in the shuttle disaster.
The point, Marder says, is that materials are often improved by finding out at what point they cease performing as they should -- and why. The concept of failure analysis is to make a better product in the end, he says.
Making future spaceflights safer

In addition to being a part of history, the 15 students gained valuable real-world experience they'll take with them into their careers.
Some of these pieces came back with pine needles and dirt on them -- these were sitting in Louisiana for a few days before they were picked up, Deacon says. And more importantly, there was a lot of data missing. In some cases, we weren't sure where a part came from and we didn't have all the information. And that's what analyses like these are like in the real world.
Mikolaj Bykowski, who analyzed a piece of a wing, feels better prepared to enter the workforce as a result of his experience. This was a tremendous opportunity, a once-in-a-lifetime shot, he says. I got to do something as an undergraduate student that most materials scientists will never get the chance to do. Hopefully, my results will help NASA design a better material to promote the safety of the crews flying the space shuttle.
The students also learned what it's like to work in a high-security environment.
Security was a big issue with this project -- it was part of the proposal Professor Marder submitted to NASA, Deacon says. Everything had to be documented. The students had to sign out their pieces and could only work on them between 8 a.m. and 5 p.m., which was an adjustment for those who like to work at the last minute at midnight. And while we normally have a pretty open lab here, the students couldn't walk away from their pieces for a second, even to just run to the next room to get something.
The students and professors involved with the project never forgot that the opportunity set before them came at the highest cost.
Throughout the time they were doing the investigation, the students always kept the seven astronauts who lost their lives in mind, Marder says. They all used a photograph of astronauts as a memorial to conclude their presentations, and I didn't have to ask them to do that -- they did it on their own. This was an awesome responsibility, and these students learned how to respond to a tragic incident and make it positive.
Cohen opened her presentation on the results of the windshield piece she analyzed with one of the final photographs taken from the Columbia before it crashed -- an image of night falling across France, England, and Ireland. There is still a lot left to be discovered through space exploration and a lot of beautiful i As part of the relationship with NASA, Lehigh invited Pam Melroy, a NASA astronaut, to speak at the closing of the student presentations. Melroy told the group she was impressed -- the students' findings closely paralleled those from NASA engineers, despite the students' limited information about the spacecraft.
She also offered words of encouragement and inspiration about the future of space travel, which includes a planned human visit to Mars in 20 to 30 years.
There is a huge amount of work left for us to do in space. And it's not just for rocket engineers, Melroy told the students. This is the challenge of your generation. And it will take all different career fields to come together and make this happen. Who knows? One of you in this room could be the first human to walk on Mars.
Related Story
In Making a difference, you'll meet Angela Capece, a mechanical engineering major who joined 14 materials science and engineering students in analyzing Columbia debris.
--Elizabeth Shimer
Kurt Pfitzer also contributed to this article.
Lehigh Alumni Bulletin
Spring 2005