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Engineers and Integrity

Engineers and Integrity

7 minutes
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June 29, 2011

Editor's note: The following article is adapted from "Professional Heroes," a talk given by Gordon Stubley at the 1997 Atlas Society Summer Seminar in Charlottesville, Virginia.

One of the distinctive features of Ayn Rand's fiction is her portrayal of heroines as engineers. A small group of fiction writers have created engineer-heroes, But Rand is unique in choosing to create two engineer-heroines: Kira Argounova in We the Living and Dagny Taggart in Atlas Shrugged. More remarkable still, Rand created two different types of engineer-heroine. For though the sense of life exhibited by the two women is similar, the two characters emphasize different engineering virtues.

The idea of engineers as innovators-striving to create new means by which life can be made easier-is fully embodied in Kira's character, despite the fact that she never had the opportunity to practice as an engineer. Kira, with her dream of building the first aluminum bridge, embodies the spirit of innovation. (In fact, the first aluminum bridge was built to span the Saguenay River in northern Quebec in 1949. I think of it as "Kira's bridge.") While other characters in Rand's fiction, such as Hank Rearden, embody this innovative spirit, I have always had a special place in my heart for Kira and her dream. Dreams like these have been behind the development of such effective building materials as aluminum, concrete, and, more recently, plastics.

On the other hand, the character of Dagny Taggart does not emphasize innovation. And in saying this I do not mean to diminish her achievements. Dagny is portrayed as an extraordinarily successful builder. Hank Rearden's innovative metal and innovative truss design were not sufficient to create the bridge to Wyatt Junction. It took Dagny's project-management skills to bring Rearden's innovations to fruition. The large-scale, complex structures in our society (such as the Confederation Bridge joining Prince Edward Island with mainland Canada, or a Boeing 747 aircraft, or the international telephone communications network) are ample evidence that the "builder" quality Rand emphasizes in Dagny's character is reflected in the practice of actual engineers.

Now, is a drive to build and innovate sufficient for successful engineering practice? Children naturally build and create innovative structures. Does this alone qualify for them engineering? Rand answers these questions by showing us how Taggart Transcontinental fares when Dagny, the engineer, is not in charge of operations. Her brief period of resignation ends after the Taggart Tunnel disaster. This disaster was not caused by a lack of building or project management inside Taggart Transcontinental. It was caused by the decision to send a coal-burning engine into the poorly ventilated tunnel. Everyone in the chain of command in Taggart Transcontinental, from James Taggart down to the train engineer, Joe Scott, was aware of the deadly risk of allowing the coal-burning engine to proceed into the tunnel and chose, explicitly or otherwise, to evade this fact. It is hard to imagine that this failure of integrity would have occurred if Dagny had been in the chain of command. As vice-president in charge of operations, Dagny continually receives information, judges it rationally, and issues orders consistent with her judgments. She acts as an engineer with integrity.

ENGINEERING INTEGRITY LOST

I have heard it argued that Ayn Rand takes points to a ridiculous extreme and that the Taggart Tunnel disaster might be such a case. After all, it is hard to imagine anyone's evading the known carbon monoxide hazard when the consequences of this evasion are so deadly.

Or is it? The space shuttle Challenger disaster of January 28, 1986 has some haunting parallels to the Taggart Tunnel disaster. That we know so many of the details of the Challenger story is a credit principally to three men: Roger Boisjoly, a design engineer employed at the time of the accident by the manufacturer of the solid fuel booster rockets, Morton Thiokol (see the summary of his testimony in the Report to the President by the Presidential Commission on the Space Shuttle Challenger Accident); Richard Feynman, a scientist on the presidential commission ("What Do You Care What Other People Think?" New York: W.W. Norton and Company, 1988); and Michael Collins, an author and former astronaut (Liftoff: The Story of America's Adventure in Space. New York: Grove Press, 1988).

The technical failure in the Challenger disaster was the failure of an O-ring seal in the joint between the lower sections of the solid-fuel booster rockets. In many respects this failure was as simple as the carbon monoxide poisoning that caused the Taggart Tunnel disaster. The two solid-fuel booster rockets mounted on the outside of the main rocket's hydrogen-oxygen fuel tank are built in four sections (each section is approximately the size of the tank on a tanker truck ), which are filled with the wax-like solid fuel. When the solid fuel begins to burn, the hot combustion gases can leak out through the small gaps in the joints between the sections. To stop this leakage, O-rings, rubber rings approximately one-quarter inch thick and twelve feet in diameter (the diameter of the rocket sections), are placed in grooves in each joint. (See author's sketch on following page.) As the combustion gases begin to flow into the gaps, the O-rings are squeezed into the gaps and the leaks are sealed. For the rubber O-rings to be able to press into the gaps in sufficient time to stop gas leakage, it is crucial that the rubber in the rings remain resilient.

Approximately one year before the Challenger flight, the solid-fuel booster rockets were being refitted after use in an earlier launch when it was noticed that about a third of several of the O-rings had been severely corroded. This indicated that there had been significant leakage of combustion gases through the joints. The investigating engineers also noted that just before launch time the air temperature was around 53 degrees Fahrenheit (the lowest launch temperature up to that point in the space shuttle program). After some internal squabbling the manufacturer of the booster rockets, Morton Thiokol, formed an engineering team to investigate the O-ring design. By April 1985 this team had carried out experiments and reported that the O-rings' resiliency decreased dramatically below 50 degrees Fahrenheit. On the night before the Challenger launch, the temperature was around 28 degrees Fahrenheit.

It is not fair to say that the O-rings failed in the Challenger launch. Given the launch conditions, there was no reason to expect that the O-rings would work. To see the real failure, one has to examine the events of the evening before the Challenger launch. At that time the predicted launch temperature was 26 degrees Fahrenheit and the predicted overnight low temperature was 18 degrees Fahrenheit. This situation was discussed in a teleconference involving senior administrators from NASA and four executives of Morton Thiokol: Jerald Mason, Senior Vice President of the aerospace division; Calvin Wiggins, Vice President and General Manager, Space Division; Joe C. Kilminster, Vice President, Space Booster Programs; and Robert K. Lund, Vice President, Engineering. After presenting the evidence of their engineering teams, Lund and Kilminster recommended that the launch be postponed until warmer air temperatures prevailed.

The administrators from NASA were appalled by this recommendation. At the time, NASA administrators felt that they were under considerable pressure to demonstrate the viability of the space shuttle program. This pressure was "strongly" communicated to the Morton Thiokol executives. Sensing NASA's reluctance, Kilminster asked to go off-line for five minutes. After the phone was hung up, Mason allegedly said, "We have to make a management decision." At this point those engineering team members present at the meeting began to reiterate to their bosses the importance of the evidence on O-ring resilience, but to no avail. Instead the senior executives struggled to find reasons to support a launch decision. As the discussion wrapped up some twenty minutes later, Mason turned to Lund and allegedly asked him to "take off your engineering hat and put on your management hat." And that is exactly what Lund did. He took off his engineering hat, and the outcome is history. (President's Commission, p. 108.)

Just as carbon monoxide poisoning was not the true cause of the Taggart Tunnel disaster, the O-ring failure was not the true cause of the Challenger disaster. Both disasters were the direct result of senior executives acting with no integrity. Lund was the front-line engineer. He knew the facts. He chose, albeit under pressure from others, to ignore the facts. The consequences were deadly.

Fortunately, large-scale disasters, like the Challenger explosion, in which lack of integrity plays a pivotal role are not common occurrences. However, the Challenger disaster is not unique. In his autobiography, Nevil Shute documents the events surrounding the British R101 Airship explosion over southern France in 1930. (N.N. Shute, Slide Rule. London, England: Windmill Press, 1954.) The roles played by the senior design engineers of this airship in allowing the trans-European flight are strikingly similar to those played by the executives of Morton Thiokol. Rand's demonstration of the consequences of acting without integrity in her portrayal of the Taggart Tunnel disaster is not a point taken to a ridiculous extreme. It is all too realistic.

ENGINEERING INTEGRITY UPHELD

What if Lund had left his engineering hat on? In all probability the Challenger disaster would have been avoided. There would not have been a Presidential Commission or any of the other publicity surrounding the disaster. In all likelihood we would have never noticed the benefits Lund would have acquired by upholding his integrity. Still, Rand's views on this are quite clear. Bob Lund would "win." It is not by accident that Howard Roark is acquitted at his trial for the demolition of the Cortlandt Housing project. Given the terms under which Roark undertook the design of the project and the unauthorized changes to his design, he is left with no choice but to demolish the project. Given the circumstances and his principles, he acts as his integrity demands. And he wins!

Is this Rand taking a point to a ridiculous extreme? Since good news is not emphasized in the media, we rarely hear the cases where integrity has been upheld. Therefore, we are extremely fortunate that Joe Morgenstern reported the story of the crisis at the Citicorp tower on Lexington Avenue between Fifty-third and Fifty-fourth Streets in New York City. "What crisis?" you may ask. Exactly! This is a story where, because an engineer acted with integrity, disaster was avoided. (J. Morgenstern, "The Fifty-Nine Story Crisis," The New Yorker, May 29, 1995, pp. 45-53.)

Built in 1977, the fifty-nine story Citicorp tower appears to sit in midair, nine stories above street level. In actual fact, it sits on four stilts or columns, each placed at the midpoint of each of its sides. This provides a very open and airy feel under the corners of the tower-a design requirement imposed by the church parish which had owned the northwest corner property on the block the tower was built on. This parish had owned the property since 1852 and the church built in 1905 was, by the 1970s, falling into disrepair. The parish sold the property to Citicorp with the understanding that a new church would be built on the corner in such a way that the church could continue to play its traditional role as a neighborhood concert hall.

The innovative design was provided by structural engineer William J. LeMessurier (pronounced "LeMeasure") working with architect Hugh Stubbins Jr. In LeMessurier's design the structure of the tower (analogous to the human skeleton) is based on the four columns, which extend almost to the top of the tower. The main part of the tower is broken into six eight-story sections. Each of these sections is tied together by diagonal braces running from the outermost corner on the top floor of the section to the middle of the lowest floor, where the braces are joined to the columns. In other words the diagonal braces hold up the floors and the columns, in turn, hold up the diagonal braces. Clearly, the joints where the diagonal braces meet the columns are crucial.

In May 1978, while working on another project, LeMessurier discovered that bolts had been used to join the diagonal braces to the columns of the Citicorp tower (by then completed and occupied). This surprised him because he had originally specified that the joints should be welded (a proper weld between two metal pieces is usually stronger than the individual metal pieces). However, when he checked into the matter, he found that the contractor had proposed the change to bolts to make construction easier and less expensive, and that, after carrying out some calculations to ensure that the bolts were strong enough, LeMessurier's chief engineer had approved the change. This was all proper practice, and so LeMessurier did not think any more of the issue at the time.

Approximately a month later, LeMessurier received a phone call from a student working on a senior-year project. To this day he does not know who the student was, but the student said, in effect: "Sir, can I bother you for a minute? I know you are a very busy man but my professor thinks you should have put the columns on the corners to better resist the loads which occur due to wind blowing on the tower."

To this query, LeMessurier explained in some detail the design problem that the church site posed, the tests required by the building code to ensure that the tower was sufficiently strong to withstand winds that blow directly on the tower front, and the roles that the diagonal braces play in supporting the tower when the winds blow both on the front and on the corners of the tower. As you can imagine, the student was impressed.

After getting off the phone, LeMessurier started to think about the loads on the structure when the wind blows on the corners of the tower. The building code had required that wind-tunnel tests be carried out with the wind blowing on the front of the tower but LeMessurier had never done calculations or tests to determine the loads for these so-called quartering winds. Thinking that it would make a good class project for the architecture students he taught at Harvard and, I also suspect, because he was justifiably curious, he set out to calculate the loads for the case of quartering winds. His quick check showed that the loads would increase in some of the joints by 40 percent. All of a sudden substituting bolted joints for welded joints became a big deal!

Still, he had not done anything wrong in the design of the structure. His company had done everything correctly. There was no professional fault on his or his company's part. Just the same, it appeared that the joints were not strong enough. His first step was to check his data and calculations in some detail. The Wind Tunnel Lab at the University of Western Ontario had performed the original scale-model tests to determine the tower's response to winds blowing on its front. Without giving the lab's director a lot of details, LeMessurier returned to the lab and asked for information on the likelihood of quartering winds, the storm patterns that lead to these winds, and the tower's overall response to a quartering wind. The answers he got were not reassuring.

On his return home, LeMessurier sequestered himself for the last weekend of July to carry out all the calculations in a detailed and systematic manner. He started at the top floor and worked his way down, in effect asking: How hard does the wind have to blow to cause the joint on this floor to fail? When he got to the thirtieth floor he found that once every sixteen years, on average, a storm would create winds strong enough to cause that joint to fail, resulting in the collapse of the tower. Now, he did not know for sure that the structure would fail in sixteen years, but he was very certain that it would not be standing in twenty-five years and it might fall in ten years, depending upon the storm patterns. He was looking at a catastrophe!

What did he do? He actually spent some time that weekend thinking about his options, including silence. In one sense, he had not done anything wrong and he was the only person aware of the problem. He had a large and successful business that depended upon his reputation as an innovative and sound designer. But, as he later put it, his state of mind was best summed up as: "Thank you, dear Lord, for making this problem so sharply defined that there's no choice to make."

On Monday he returned to work and began to act on his knowledge. Unable to reach Hugh Stubbins, he called the architect's lawyer. He was advised to call his insurance company, which he did. He flew to meet the insurance company's lawyers in New York City, and a response team was formed.

On Wednesday LeMessurier and Stubbins met with John S. Reed, a Citicorp executive vice-president, to explain the situation. LeMessurier began with "I have a real problem for you, sir," and then went on to outline the problem and his proposed solution to his client. The solution was easy-simply weld plates onto each joint to provide reinforcement. But the logistics of removing drywall, housing welding equipment, monitoring the stress levels in the joints, and so forth, in a building with tenants, were awesome. And the repairs had to be done quickly, for the fall hurricane season was rapidly approaching.

Reed thanked the men for explaining the situation and asked them to be available for further meetings. That afternoon they were back in Citicorp headquarters. This time they explained the situation to Walter Wriston, chairman of the bank. Upon hearing the situation, Wriston said, "I guess my job is to handle the public relations of this, so I'll have to start drafting a press release." Clearly, Citicorp was on board, and the repairs were to be done with due haste. The most crucial repairs were made within four weeks, and all of the repairs were finished by November. To this day the Citicorp tower stands tall-a triumph of engineering innovation and integrity.

But this great story does not end there. As the repairs were being finished, Stubbins and LeMessurier returned to meet with the bank to discuss the financial settlements. Even though the bank has never released the total bill for the repairs, estimates of the costs suggest that they exceeded 8 million dollars. The bank settled for 2 million dollars (the extent of LeMessurier's liability insurance coverage) and agreed that it had no fault with LeMessurier's firm. The last detail was to reevaluate LeMessurier's insurance premiums. In spite of the large claim, his insurance company lowered his premiums. It understood that his character made him a good risk.

In short, as Morgenstern wrote, this story "produced heroes, but no villains; everyone connected with the repairs behaved in an exemplary fashion." Of course, a cynic might say that LeMessurier was just lucky to be dealing with especially nice people. But I do not think that that is the answer-too many people were involved for that to be true. I think that his policy of integrity, of looking clearly at the facts and of stating clearly what had to be done, set a tone that everyone followed. Seeing how this story has unfolded, it is clear that Rand's portrayal of Roark's courtroom scene is not a point taken to a ridiculous extreme. It is reassuringly realistic.

While uplifting stories like the Citicorp tower crisis are very rarely told, they nonetheless exist. Behind every bridge we safely cross, every plane ride we safely take, and every X-ray we safely receive stands the integrity of men and women working to the code so aptly expressed by LeMessurier after his weekend of calculation and evaluation. Once these engineers see clearly what ought to be done, deciding to do it does not seem like a separate choice; it follows as a matter of principle. To these men and women, quiet heroes of integrity, we owe a debt of gratitude for providing the benevolent technology we rely upon.

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Ciência e Tecnologia