The ring froze, the shuttle exploded

The most instructive lesson about the importance of the small details was received by NASA after the Challenger disaster 17 years ago. The brilliant physicist Richard Feynman's conclusions from that disaster seem more relevant than ever.

In the first week of February 1986, the phone rang at physicist Richard Feynman's house. On the line was the head of NASA, William Graham. He wanted to know if Feynman was willing to participate in the committee that would investigate what happened to the Challenger. The space shuttle exploded during launch a few days earlier, on January 26, and seven crew members perished. Feynman, a gifted scientist, a Nobel laureate, considered one of the greatest physicists of the twentieth century, said he had to think about it.

In the meantime, the status of the investigative team was upgraded. Not an "investigation" but a "presidential commission" headed by William Rogers, the former Secretary of State, whom President Reagan appointed to investigate the disaster. Rogers was completely unaware of a second, smaller disaster that befell him that very day: Richard Feynman gave Graham a positive answer.

During World War II, Feynman was one of Robert Oppenheimer's team of scientists in the "Manhattan Project" to build the American atomic bomb. He received the Nobel Prize in 1948 for the "theory of quantum electrodynamics". He was not only a great scientist but also a charismatic, curious, convention-breaking and adventurous person. He published science and prose books, he had an unusual ability to tell stories, and to make people laugh. Playful, womanizer, amateur drummer, one who always says what he thinks, and always does what he wants. He gained a reputation as someone who doesn't give an account to the establishment, a person with creative and original thinking and a rare ability to abstract.

Armed with all of these, Feynman showed up that week in Washington, determined to carry out the task assigned to him with full vigor and thoroughness. He soon occupied the throne of the expert witness, "the professor", and became the number one professional authority among the members of the committee. He did the death to Rogers, left no stone unturned, never heeded instructions, interrogated whoever he wanted, however he wanted. Therefore, no one was really surprised that Feynman also found the solution to the mystery.

One morning, in a discussion broadcast around the world, Feynman demonstrated the main failure that caused the shuttle to crash in a simple, almost primitive experiment: he dropped a rubber ring into a glass of ice water and showed how it lost its elasticity - just as happened to the seals of the shuttle, which lost their elasticity due to the cold that prevailed that day The launch. Therefore they no longer function well as seals, hot gas leaked and caused an explosion.
On his way to Washington, Feynman decided to keep an accurate record of every action, meeting and thought he would have during the investigation. From there until the publication of a book that revealed how the investigation into the Challenger disaster was conducted behind the scenes, the road was paved. Feynman did not get to see this book published; His wife Gwyneth and his good friend Ralph Leighton collected the notes, edited them, and published the book in '88, the year he died of cancer.

The book, "What do other people think" (published in Israel in 96 by Zamora Beitan, translated by Emanuel Lotam), opens with two personal stories, about his first wife Arlene, who died of an illness at a young age, and about his father. But most of it deals with the investigation of the disaster.

17 years have passed since then. The ferry that crashed this time is called Columbia. It blew up on landing, not launch. Feynman's book is of course a document that testifies to what was, not what will be. But this is an instructive document of an instructive man, who played a central role in exposing the omissions that led to the explosion of the shuttle.

Last week, the White House announced that three teams of the American government will investigate the causes of the Columbia space shuttle disaster: an "independent" investigative team led by Harold Gehman, a former admiral in the United States Navy; NASA Internal Investigation Team; and an investigation on behalf of the Science Committee of the House of Representatives. Will a successor to Richard Feynman be discovered in one of these teams?

Mr. Rogers didn't understand

Feynman did not wait for the first meeting of the committee members. He arranged a meeting with engineers and technical people at JPL (NASA's Jet Propulsion Laboratories) in Pasadena. "When I go through my notes now," he wrote, "I see how quickly they actually gave me clues about everything I needed to look for in investigating the shuttle problems. The first line of my lists says 'combustion control. Inner shroud' (to prevent the burning fuel from breaking through the metal side of the accelerator rocket, there is an inner shroud that didn't work properly)... the second line says 'O-rings show scorching in a fork test'. It has already been noticed that hot gas bursts from time to time through the gasket rings in the field connections of the accelerator rockets... and in the same line it says 'Zn CrO4 makes bubbles' (chromic zinc used as a putty that is compressed for insulation behind the gasket rings). "It creates bubbles that can grow very quickly when hot gas leaks through them, and that wears out the gasket rings."

Feynman was enthusiastic. He felt he had started the investigation on the right foot. And he was very pleased with the engineers and technicians he met. "This briefing was very thorough, very quick and very complete. It's the only way I know of to get technical information quickly: you don't sit and listen until they go over everything they think is interesting; Instead you ask lots of questions, you immediately begin to understand the circumstances, learn exactly what to ask to get the next piece of information you need. I received an outstanding education that day, and I absorbed all the information like a sponge."

Two days later he flew to Washington to attend the first official meeting of the committee, where its members were supposed to receive a general briefing from the "heavy guns" of NASA. "The first thing we had to learn is the crazy acronyms that NASA uses for all kinds of things: MDMs are solid fuel engines, which are the main part of the RDMs, solid fuel booster rockets. The rockets are the main engines of the space shuttle; They burn Mn (liquid hydrogen) and Hn (liquid oxygen) which are stored in the fuel tank (from any external fuel). Everything has letters... Then we learned what 'balls' are - small black circles that come before sections that are supposed to summarize all kinds of things. In the instruction manuals and slides we received there were a lot of such damn bullets, one after the other."

Already at the first meeting, the seniors encountered difficult questions. "It turned out that except for Rogers and Mutchison, who were lawyers, and Hoch, who was an editor, we all had science degrees: General Kutina got his from MIT; Armstrong (the first man on the moon), Kubert, Rommel, and Starr were all aeronautical engineers, while Miz Reid (Sally, the first woman in space), Walker, Veillon, and I were all physicists. It also turned out that most of us did some preparatory work on our own. We asked a lot of technical questions, and it turned out that some of these heavy guns weren't ready for them. When one of them was unable to answer a question, Rogers assured him that we understand that he did not expect such detailed questions, and we are willing to settle for now with their eternal answer, 'We will get you that information later.'"

Already at this early stage, Feynman lost his faith in the committee's investigative procedures. "The main thing I learned at that meeting is that public inquiry is a completely ineffective business: most of the time, other people ask questions that you already know the answers to - or the answers to which you are not interested in - and you get so confused, you hardly notice that someone skipped a point important. What a contrast compared to JPL, when they fed me a lot of information at an enormous speed."

On that day, Feynman also lost his faith in the chairman of the committee. "Rogers was delayed for some reason, so while we were waiting for him General Kutina offered to tell us what an accident investigation looks like. He explained to us how the Air Force acted in the investigation of a malfunction that happened to an unmanned Titan missile... He warned us that sometimes it seems as if the reason is obvious, but when you investigate more deeply you start to change your mind. They had very few leads and changed their minds three times. I'm really excited. I want to do this kind of investigation and I think we can start right away... But Rogers, arriving in the middle of General Kutina's talk, says, 'Yes, your investigation was a great success, General, but we can't use your methods here, because we cannot receive the amounts of information you received'.

"It is possible that Rogers, who has no technical training, did not realize that these things were simply not true," Feynman wrote. "The Titan, it didn't have anything even close to the number of testing devices that were on the shuttle. And we had television pictures that showed the extraordinary flame of the booster rocket a few seconds before the explosion! Whereas all we could see in General Kutina's photos of the Titan was a bloody dot in the sky – a little flash, a sizzle – and he was able to draw conclusions from that!”

Ignoring and gagging

"Rogers says, 'I've arranged for us to visit Florida next Thursday. We will receive a briefing there from NASA personnel, and they will take us to the Kennedy Space Center. I see before me the picture of the Tsarina visiting the village of Potyomkin: everything is arranged and ready; We are shown what the rocket looks like and how it is assembled. That's not how you find out what really happened... All this worried me a lot, because the only things I imagined I had to do were technical...

"I started suggesting things we could do. When I'm in the middle of my list, a secretary comes in with a letter that Mr. Rogers needs to sign. Meanwhile, as I sit quietly and wait for him to allow me to continue, several members of the committee offer to work together with me. Then Rogers raises his head and continues the meeting, but he gives the floor to someone else - as if he was just distracted and forgot that he stopped me in the middle. So I ask for permission to speak again, but as soon as I start my piece again another 'glitch' happens.

"Actually, Rogers locked the session when I was in the middle of speaking. He returned and expressed his fear that we would never be able to understand what happened to the shuttle. It was absolutely frustrating… I couldn't stand it. I thought 'I'm already dead. This damn business isn't working right.' I returned to my hotel devastated. I remembered Bill Graham. I called him, 'Listen Bill', I told him. 'You got me into this business. Now you have to save me. I am totally depressed. I can't stand it'. He says, what happened? 'I want to do something! I want to go around and talk to the engineers.'
He says, sure. Why not? I will arrange a ride for you. You can go wherever you want… So I said, 'I'm going to Johnson.' All right, he says, I'll tell David Atchison. He is a personal friend of Rogers and he is a friend of mine. I'm sure everything will be fine."

But nothing was right. William Rogers strongly opposed the idea of ​​Feynman moving freely and conducting his own investigations. "We must act in an orderly manner," he told him. Then the following conversation took place between them:

Feynman: "But we already had meetings and we still haven't been assigned anything to do."

Rogers: "Well, do you want me to bother all the other members of the committee and call a special meeting on Monday so we can assign tasks?

Feynman: "Yes, absolutely" (and he comments in his book: "In my opinion, our job was to work, so there was room to bother us, do you understand what I'm saying? So he changes the subject"):

Rogers: "Of course, I understand that you don't like your hotel. Let's move you to a better hotel."

Feynman: "No thanks, my hotel is perfectly fine."

A short time later, Feynman writes, Rogers tried again to bring up the matter of the hotel.
"So I say to him, 'Mr. Rogers, what I'm interested in is not my personal comfort. I'm trying to do work. I want to do something'. Eventually Rogers says I'm allowed to cross the road and talk to the people at NASA. It was completely clear that Rogers needed me like a thorn in the ass."

If the gun didn't fire

A few days passed. Bill Graham, trying to lift Feynman's spirits, took him to visit the National Air and Space Museum. Feynman was as enthusiastic as a child.
"The museum had a special screening room with a film about NASA and its achievements. The movie was great. I didn't really realize what a huge number of people worked on the shuttle, and what effort they put into it... This movie was so dramatic that I almost started crying. I understood that the accident was a terrible blow. To think that so many people worked so hard for it to succeed and suddenly it explodes - and I became even more determined in my decision to clear up the shuttle's problems as soon as possible, so that all those people could get back on track. After seeing this film, I changed a lot, from an almost anti-NASA attitude to a very strong pro-NASA attitude."

Feynman continued a focused investigation of the gasket problem. From one engineer, Mr. Weeks, he learned that "there is putty, and there are other things, but the final seal is supposed to be two rubber rings called 'seal rings'... that suffered from blackening and what they called 'wear' where the seal ring had burned a little. There was a chart that showed all the (previous) flights, how severe the blowout and erosion were... I said, 'Where have they (NASA) even discussed the problem - how is it progressing, if there is any progress at all?' The only place was a 'flight readiness review'".

Weeks and Feynman went over the summary of the report. "Everything was marked with small balls, as usual." The top line read:

* The absence of a good secondary seal in the field connection is a very critical matter and ways must be found to reduce the rotation of the connection as soon as possible to reduce the criticality...

Then, near the end, it was written:

* From the analysis of the existing data, it appears that there is no safety problem in the continuation of the flight of the existing design, as long as all the connections are checked for leaks in the stabilization.
"This contradiction amazed me," wrote Feynman. "If it is 'extremely critical', how is it that there is 'no flight safety problem'? Where is the logic here?
"Weeks, the NASA seal expert, went back through the report with me and found the analysis... The analysis concluded that a small unexpected leak here and there was something that could be tolerated... If all the seals were leaking, it would have been clear even to NASA that the problem was serious. But if one of the seals leaks a little and the flight was successful, it means that the problem is not so serious. Try playing Russian roulette like this: you pull the trigger, and if the gun doesn't fire, it means you can pull the trigger again."

Feynman was not the only one who was aware of this fallacy. "An engineer from the Thiokol company (which carries out the sealing of the various parts in its factories in Utah) arrived, one Mr. MacDonald. He wanted to tell us something. He came to our yeshiva without an invitation. MacDonald reported that Thiokol's engineers had concluded that there was some connection between low temperatures and the sealing problem, and that was of great concern to them. The night before the launch they told NASA that the shuttle should not be launched at a temperature below 11 degrees - the lowest temperature it had been before - and that morning it was minus two!

McDonald said NASA was 'shocked' by the announcement. The man on her behalf who presided over the meeting at the time, Ahad, Mr. Malloy, claimed that the evidence was 'incomplete' - on several flights there was erosion and exhalation at a temperature higher than 11 degrees, and therefore Thiokol should reconsider its objection to the flight. Thiokol recanted, but MacDonald refused to join, he said: 'If something goes wrong with this flight, I don't want to stand before a commission of inquiry and say that I stood up and told them they could fly this thing beyond what it was capable of doing'...

"The entire committee was shocked," wrote Feynman. "Not only was there a fault with the seals, but there was probably a fault with the management as well."

The engineers scream "save"

That night Feynman had trouble sleeping. He had to see what happens to a rubber ring - made of exactly the same rubber as the gasket rings - at a low temperature. Early in the morning, he asked the driver to drive him to a hardware store, where he purchased screwdrivers, pliers and small clamps. With Graham's help, he managed to get his hands on a model of the shuttle that had two small pieces of this rubber in it, and extracted them from it. And with all these things he showed up at the next meeting. He asked for a glass of ice water to be brought to him, placed the rubber in the water for a few minutes, took it out and said: "I discovered that when you release the clamps, the rubber does not immediately bounce back. For a few seconds there is no flexibility in this particular material, when the temperature is zero degrees. It seems to me that this has significance for the problem before us.'

"Before Meloy has enough to say anything, Rogers says: 'We will examine this matter thoroughly, of course, in a meeting that will deal with the weather, I think this is an important point. I am sure that Meloi recognizes this and is going to respond to this in one of the next meetings.''

But the journalists realized that Feynman had found something important. "During the lunch break, the reporters approached me and asked questions like, 'Were you talking about the o-ring or the soup?' or 'Would you mind explaining exactly what an o-ring is?' So I was quite depressed, because I thought I failed to make the point. But that evening all the television news caught the meaning of the experiment, and the next day, the articles in the press explained everything perfectly."

A few days later, the committee left for Florida, to the Kennedy Space Center at Cape Canaveral. Before starting their work there they held an open meeting. "First, we saw some detailed pictures of the smoke coming out of the shuttle while it was still on the launch pad. There are a lot of cameras in all kinds of places that follow the launch - maybe a hundred. Where the smoke came out, there were two cameras looking straight at it - but both broke down, how strange."

The next morning the members of the committee heard people from Teukol and NASA talking about the night before the launch. "Everything came out slowly: the witness doesn't really want to tell everything, so you have to get the answers out of him, and for that you have to ask exactly the right questions." At this point, Feynman recognized a dangerous short in the communication between the engineers and the managers working on the booster rockets. In the next test he discovered that the same dangerous short also impairs the communication between the engineers and the managers who work on the engine.

"I had a clear feeling that I found here the same game that I saw in Atima: the management is constantly lowering the bar and accepting more and more errors that were not part of the original design, while the engineers are screaming from below 'Save!' or 'Emergency!'". In the episode "Afterthoughts" Feynman concluded: "Whenever we talked to high-level managers, they always said that they knew nothing about the problems below them... So either the people at the top didn't know, in which case they should have known, or they did, and in this case They lied to us... I came up with a theory... and now I will tell you what I think caused this lack of communication at NASA."

The exaggeration theory

"When NASA tried to reach the moon, there was a lot of enthusiasm: it was a goal that everyone was eager to achieve. They didn't know if they could do it, but they all worked together. I thought about this because I worked at Los Alamos and experienced for myself the tensions and pressures when everyone worked together to build the atomic bomb. If someone had a problem - say, with the explosive - everyone knew it was a big problem, thought of ways to overcome it, and offered suggestions. And when they heard the solution they were excited, because it said that their work would not be in vain now.

"I imagined that a similar thing happened at NASA in the early days: if the space suit didn't work, you couldn't fly to the moon. So everyone was interested in everyone else's problems. But then, when the joint project ended, NASA had a lot of people: there is a big organization in Houston, and a big organization in Huntsville, not to mention Kennedy in Florida. You don't want to fire people and send them out on the street after you finish a big project, so the problem is, what do you do? You have to convince Congress that there are projects that only NASA can do. For this you must, apparently, in this case, exaggerate. Exaggerate when you explain how economical the shuttle will be, exaggerate when you say how often it will be able to fly, exaggerate when you describe its safety, exaggerate about the great scientific facts that will be discovered with its help.

"Meanwhile, I would guess, the engineers below are saying: 'No, not true! We can't do that many flights. If we have to make so many flights, it means so-and-so'. Or 'No, we can't do it with this amount, because that means we'll have to do so-and-so'. Well, the people trying to get Congress to approve the projects don't want to hear that kind of talk. It's better that they don't hear them, because then they can be more 'honest' - they don't want to be caught lying to Congress! So quite quickly the references start to change: unwanted information from below - 'We have a problem with the sealing; We need to fix it before we continue to fly' - met with silence from the heavy guns and middle managers who say, 'If you tell me about the sealing problems, we will have to ground the shuttle and fix it.' Or 'No, no, keep flying, because otherwise it will look bad'. or 'Don't tell me, I don't want to hear'.

"Maybe they don't explicitly say 'don't tell me,' but they stifle the communication, and it's exactly the same thing... If you try to communicate a problem once or twice and run into a wall, pretty quickly you decide 'let them all go to hell'... because the exaggeration at the top didn't match the The reality is at the bottom, the communication has slowed down until it has been completely choked. Therefore, it is possible that the heavy guns really did not know."

Nature cannot be tricked

William Rogers did not like the draft of the report that Richard Feynman wrote. For weeks, according to the book, various attempts were made to rewrite it, change it, cancel it, push it to the margins, to the point that Feynman was already mentally and logistically prepared to publish his report in the press, outside of the committee's report. But NASA realized that it would be even worse for them, and at the last minute, the report was inserted as an "appendix".

Did President Reagan exert overt or covert pressure to launch the shuttle on time?
Feynman concluded that this was not necessary. "By the time the committee finished working, I understood much better the nature of the operation in Washington and NASA. I learned, by seeing how they work, that the people in a large system like NASA know what needs to be done without being told. In any case, there was already great pressure to continue the shuttle flights. NASA had a flight schedule that it tried to stick to, just to prove what NASA is capable of doing - and it doesn't matter if the president is going to give a speech tonight or not. So I don't believe there was any direct White House activity, or special effort. There was no need for that."

In the conclusion chapter, Feynman wrote: "In order to maintain a reasonable launch plan, the engineering work must be done very quickly, to meet the expectations of the original conservative standards for approval, designed to ensure a very safe vehicle; This turned out to be impossible in many cases. In such situations, slight changes were made to the safety standards - based on seemingly logical reasons, in most cases - to allow the approval of the flights at a later date. Because of this, the shuttle flew in relatively poor safety conditions, that is, a chance of failure of approximately one percent. The official management, on the other hand, claims that its assessment of the probability of failure is a thousand times smaller than this!

"One of the reasons for this is perhaps an attempt to present NASA to the government as having a perfect success rate, in order to secure its budget. Another reason could be a complete belief in the correctness of this number, which indicates an unbelievable communication gap between the management and the engineers subordinate to it. In any case, this had extremely unfortunate results, and the most serious of them was the call to ordinary citizens to fly in such a dangerous vehicle - as if it reached the safety level of a normal passenger plane. The astronauts, as test pilots, need to know what the risk is, and we respect them for their courage."

Feynman also added recommendations to the conclusions: "We recommend that steps be taken to strengthen the relationship between senior NASA officials and the world of reality, so that they understand the technological weaknesses and flaws to such an extent that it motivates them to take actual action to eliminate them." They must live in the real world as they compare the cost and return of the shuttle to other methods of going into space. They must be realistic in entering into contracts and assessing the costs and difficulties of each project. They must make realistic flight schedules - which have a reasonable chance of being met.

"If the result is that the government stops supporting NASA, so be it. NASA owes the citizens, whose support it seeks, openness, honesty, and reliable information, so that these citizens can make informed decisions regarding the use of their limited resources. When dealing with successful technology, the sense of reality must come before public relations. Because nature cannot be tricked."

What a shame that Richard Feynman is dead and you can't ask him if, in his opinion, NASA has learned its lesson. *