Space Shuttle Challenger: Mission STS-51-L. An Engineer’s view to the disaster
A full-length interview with Burton Dicht, the Director of Student & Academic Education Programs for the IEEE. A mechanical engineer with experience in the aerospace industry, designing aircrafts.
A very interesting documentary was released lately by Netflix, called Challenger: The Final Flight. This documentary focuses on the 1986 Challenger space shuttle disaster. I have very intense memories from this accident and thus I saw all 4 episodes at once. By watching the documentary I still have questions not answered. So, I couldn’t think of a more appropriate person to address them than Burton Dicht.
Burton Dicht is the Director of Student & Academic Education Programs for the IEEE. In this capacity, he is responsible for the development and implementation of educational programs for engineering faculty and students. He began his career in the aerospace industry at Northrop Grumman in 1982 and during his aerospace career he made important design contributions on the F-5E/F, F-20A, YF-23A and F-18E/F projects.
Burton Dicht received his B.S. in Mechanical Engineering from Temple University and an M.A. in History from California State University, Northridge. He has authored numerous articles on aerospace history and is a frequent guest speaker on aviation and space topics. Burton Dicht also serves as an Exhibit Explainer for the Intrepid Sea, Air and Space Museum in NYC and as a Captain and Aerospace Education Officer for the Phoenix Composite Squadron (NYC) of the Civil Air Patrol.
You were into the aerospace industry when the Challenger disaster occurred. Were you watching the launch live ? What were your feelings when you saw the explosion?
I did not see the launch live. I was working as an engineer for Northrop Aircraft in Los Angeles. The accident occurred at 8:40 am PT and I was in a design review meeting at the time. When I went back to my office a colleague told me he heard that Challenger exploded. My first reaction was disbelief. The reaction around the engineering department was shock. We went to the cafeteria where they had a TV and we saw the replay. Disbelief turned quickly to intense sadness. It was difficult to concentrate the rest of the day and the sadness lasted a long time. I do remember a colleague asked me soon after if I still wanted to fly into space. I remember I answered, “If they asked me to go on the next flight, I would say yes in an instant.”
Have you faced such accidents, with or without fatalities, on aircrafts you have designed?
When you design high performance jet aircraft you pay a lot of attention to safety. But you certainly recognize that it’s dangerous and the potential for an accident is always there. Just before I started as an engineer at Northrop in January 1982, the Thunderbirds, the USAF’s flight demonstration team, crashed during a practice run. All four planes crashed and the pilots were killed.
The Thunderbirds were flying Northrop T-38s. It was a sad time for the company and I took notice that engineers who design these vehicles have a sense of obligation to get it right because lives are on the line. The F-20 Tigershark, a plane I helped design, suffered two crashes within 9 months in 1984-85. Both pilots were killed and I had known them. That really makes it personal. Even though the accidents were attributed to G-LOC, or gravity induced loss of consciousness, all of the engineers doubled their efforts to focus on design safety.
Is the cause of the explosion that was announced convincing or you think there were more than one causes?
I accept the conclusion of the Presidential Commission. The accident was caused by the failure of the pressure seal in the aft field joint of the right Solid Rocket Booster (SRB). The cold temperature was a factor in that it impacted the effectiveness of the O-ring seal. While that was the technical cause, there clearly was so much more to it, the cumulative impact of decisions as the program moved forward. The Presidential Commission said the accident was “rooted in history.”
The design flaw in the joint became apparent right away. The O-ring erosion, discovered after each flight was pronounced, yet the program moved forward and launches continued. Why was it not addressed and solved? Sociologist Diane Vaughn, in her book “The Challenger Launch Decision,” examined NASA’s culture. What she found was common in corporate culture in general and she termed it the “Normalization of Deviance.”
She defined it as “a process where a clearly unsafe practice comes to be considered normal if it does not immediately cause a catastrophe: “a long incubation period [before a final disaster] with early warning signs that were either misinterpreted, ignored or missed completely”
In the case of the space shuttle, O-ring erosion was clearly a deviation from the norm.There was enough documentation from engineers that the erosion was a concern, but over time as the flights continued and nothing bad happened, O-ring erosion became the new normal. They determined that there was an “acceptable risk” and no one said, “Hey, this is not right. We need to fix it before something bad does happen.” The people involved were dedicated and skilled engineers, but they were all human and prone to human failings. .
There is a quote that “space is hard.” The Challenger accident, and the subsequent accident of Columbia in 2003 demonstrate that safety must be paramount in human spaceflight. It is very unforgiving of mistakes and we can’t let the “Normalization of Deviance” creep into the decision making.
A method we engineers use during the design process is trial and error. How does it feel to design products that trial and error is not an option?
As an engineer, I never wavered from the engineering design process (EDP). It was always part of my everyday life as an engineer. To me, it would be a challenge not to employ trial and error. Few engineers get it right the first time. And the fundamental benefit of the EDP is to learn from designs that don’t work. You can learn much from failure and you only want failure during the test phase and not when customers are using the product.
Why do you think NASA insisted on launching Challenger and not wait until the temperature reaches acceptable levels? Was it just the cold war ?
That has been one of the most closely examined questions coming out of the accident investigation and I don’t think there is a definitive answer. There was certainly program pressure, to have the shuttle program perform on a regular basis. What had been conceived as regular transportation to low Earth orbit was anything but. In fact the most launches in a year was nine, which occurred in the prior year 1985.
So they wanted to fly as often as they could. What has also come out was that there might have been political pressures, but I have not seen evidence, such as the President’s State of the Union address that evening and it would have been great to tout the launch of the “Teacher in Space.” There was also schedule pressure. Christa McAuliffe was scheduled to conduct her lesson plans on Friday. The weather forecast was much warmer for the next day, but had they waited one more day her lesson plans would have taken place on a Saturday, when no students are in school.
I think in the end, the final decision makers on NASA’s side didn’t believe there had been a link made between the cold temperature and increased risk associated with the O-rings. So they made a decision that they didn’t think added any danger. The Presidential Commission report also documented that those involved in the decision to launch indicated they received no external pressure to launch. It was a decision they made.
As a manager, how do you manage to meet the deadlines and at the same time lower the risk? Is it difficult to balance between the rush to go ahead of competition and the risk of failure?
There is that infamous quote from the Thiokol general manager who told his team to “take off your engineering hat and put on your management hat, ” which gave the go-ahead for launch. And of course we know what happened next. All engineering design is fundamentally a compromise, with the need to balance competing criteria, including cost and safety.
Engineers and engineering managers must do an intricate balancing act that weighs cost and schedule versus what is acceptable risk. How people define what acceptable risk is depends on the business culture of the company and the product. When I worked at Northrop as designer, I worked closely with the Safety and Survivability group. The engineers there were experts and I could always count on them to conduct an independent assessment of our designs.
Having that independent safety group really benefited the design team and helped ensure we were not cutting corners.In the end, it will always be a challenge to balance these competing criteria, but when it comes to public safety, you must err on the conservative side.
As seen in the documentary, the USA government decided that the first non astronaut crew member should be a teacher and in 2007 a teacher, Barbara Morgan, flew with the Endeavour and spoke to students at Challenger Center. Why do you think the USA Government insists on sending a teacher in space?
The space shuttle was designed with the intention of making spaceflight routine. From a technical point of view, the shuttle was quite complicated, so the intricacies of spaceflight were not routine. However, from the public view, the shuttle launches did not seem anything special and public interest in space was waning.
NASA was looking for a way to spur public interest and the great thing about the shuttle’s flight profile was that it allowed anyone in good general health to fly onboard. Up to the Teacher in Space program, NASA had flown non-astronauts as payload specialists. These individuals were not professional astronauts, but worked for companies that had payloads on board. NASA even flew a congressman and senator. But these people did not attract public attention.
As NASA explored ideas on who to fly, such as artists or reporters, President Reagan made the decision to fly a teacher. It was actually an inspired idea. Teachers are so important to the development of our society. Flying a teacher would inspire students and also spur interest in mathematics, science, and space. And ultimately, it would honor teachers. Unfortunately, the accident caused the end of the program and NASA abandoned ideas for sending members of the general public into space.
The great thing about Barbara Morgan, who was a teacher and Christa McAuliffe’s backup, is that when she flew in 2007, she had actually become a NASA astronaut.
Can IEEE Educational Activities motivate students to follow the Engineering path and at the same time arm Engineers with ethics and wisdom so that that kind of accidents do not happen? How does IEEE do that?
Educational Activities is very involved in creating awareness and inspiring students to consider and choose careers in engineering and STEM. Our pre-university STEM activities include tryengineering.org, a website that provides teachers and students with resources, Tryengineering Together, an e-mentoring platform for 3rd to 5th grade students and the TryEngineering Summer Institute, two-week overnight camps to introduce students to engineering careers.
What we are trying to do with these programs is really get students aware and interested in engineering careers. We don’t attempt to push them to one field because in most cases they don’t even know what engineering is and how engineers impact our lives. So we concentrate on those aspects of the profession. We emphasize that engineers make the world a better place and do good for humanity. Factoring safety and ethics is a little much for them, although we do stress one role of engineers is to protect lives. .
In my experience, the most effective place to introduce ethics is in engineering programs. Some programs and universities have a required ethics course or program. This is where we can have the most impact, as students are learning the engineering basics. There is a role for IEEE. Having members of IEEE sections visiting students and conducting ethics workshops are very effective. Making it real-world can have a significant impact.
Which is the most difficult to design: Educational Programs and activities for children or aircrafts?
A good question. Designing advanced fighter aircraft was very challenging. My education and my on-the-job experience prepared me. There were times, however, I didn’t know if we would solve the problem. There were always people and resources to help and in the end I found it very rewarding. Developing educational programs for children is an entirely different challenge. I learned early on that you can’t approach it as an engineer. And you need to adapt to the age of the student. A 10 year old has a different comprehension level than a 15 year old. You need to be to tell your story in the way kids learn and understand.
That is something they do not teach us in engineering school. Understanding the practice of teaching is called pedagogy. And it’s very important when you are developing programs, especially STEM programs that you develop the teaching techniques you will need so kids will understand and appreciate what you are sharing.
A good example of this involves the writing of curriculum materials for TryEngineering Together. I was asked to develop the unit titled “Humans in Space” and write the teacher guide. I know the engineering around the topic, but how do you develop the content and make it useful for a teacher that is not an engineer and for 3rd to 5th grade students to understand? I found out it was very hard, Luckily I had the assistance of our education experts at Cricket Media. One of the articles I wrote was called Women in Space. You quickly learn about something called the Lexile scale, which measures the reading comprehension level for what was written.
As much as I tried to write the article for an audience of 5th graders, the Lexile scale was coming out too high. I needed the help of an expert to guide me and ensure the article was appropriate for the audience. So no matter our technical skill or knowledge, we need to focus on the audience we are aiming to impact. That is the challenge of pre-university STEM education. (Let me know what you think of the article.)