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National Museum of Nuclear Science & History

D.M. Ellett’s Interview

Manhattan Project Locations:

D. M. Ellett is a mechanical engineer who joined the Manhattan Project after the end of World War II. He was a member of Z Division, which was assigned to Sandia Base in Albuquerque, New Mexico in 1945. In the interview, Ellett recalls his arrival in Albuquerque and shares stories from his long career at Sandia (today, Sandia National Laboratories). He describes his years as a docent at the National Museum of Nuclear Science and History, and recalls witnessing a nuclear test in Nevada.

Date of Interview:
October 17, 2017
Location of the Interview:


Nate Weisenberg: My name is Nate Weisenberg. It is Tuesday, October 17, 2017. I’m here in Albuquerque, New Mexico with D. Ellett. My first question for you is if you could please say your name and spell it.

D.M. Ellett: It’s D, initial only, M, Ellett, E-l-l-e-t-t.

Weisenberg: Tell us a little bit about your childhood and early life. When and where were you born?

Ellett: I was born in Richmond, Virginia in 1922. I grew up in Richmond and Charlottesville, Virginia. I went to St. Christopher’s Boys School in Richmond. I went to the University of Virginia. I entered to get a degree in engineering and was in my engineering degree in mechanical engineering when the bomb was dropped [misspoke: the attack on Pearl Harbor], and we got into World War II.

I had already enlisted in the reserves when I was still in school. I went and took ordnance basic training. At that time, the military was interested in keeping track of people with technical degrees. They allowed them to complete their work, but as soon as I was finished, in March of 1943, I was called into active duty. I ended up at the University of Illinois under what was called the Non-AME ASTP. The non-A meant it was a higher degree; ME was my degree level; ASTP, the Army Specialized Training Program.

Well, after I got a commission, I served in various positions in the Corps of Engineers, but, toward the end of the war, I was selected to be on a team of seven officers for the Chinese Infantry Division. We would act as advisors on looking at possibilities of certain maneuvers, for instance. They had sent me to the University of California for a total immersion course in Chinese. Well, the bomb dropped while I was in that course, and the war was over. Even though I’d gotten cholera shots and yellow fever and so forth to fly into China, the deal was off, and I had to look for a new assignment.

I had become very interested in things nuclear. It was then called strictly atomic, of course. I asked if I could go to the Manhattan program. When the war was over, there was immediate wish by many of the people at Los Alamos – who were professors and graduate students, as well as people who were brought in from the military – they wanted to go back to their colleges. So there was a drain of people from there, and the Manhattan Project was then looking for people who could act as fillers. I was chosen as one of those fillers assigned to Los Alamos to take the position of some of the people who had gone on back to their universities.

When that was happening, of course, there was a great foment in the ranks, and it was very unsure at that time exactly what would happen to the Manhattan District. Well, at the end of the war, the regents of Los Alamos had made a conscious decision that they did not want to do the job of taking a nuclear blast and making it into a military device. That portion, the weaponization of nuclear energy, had been done under Captain [William S.] “Deak” Parsons in those days. He was promoted to Admiral at the end of war, of course. They took that division of Los Alamos that had been under Deak Parsons, the Z Division, and moved it to Albuquerque. It became Sandia Laboratory, a division of Los Alamos.

At that time, we did not know at Sandia whether we were to become an Army arsenal, or whether we would end up under civilian control. The civilian control had not been set up by that time. Of course, Congress had the wisdom, I guess, of turning it over and establishing the Atomic Energy Commission. A civilian organization which would take over the manufacture and procurement of atomic bombs, as they were called in those days, to use. They would be kept under the control of the AEC.

I was in this move. Well, I moved down from Albuquerque after just a several days’ tour at Los Alamos. I came down to Albuquerque as a second lieutenant in the division. I was assigned to Group Z-6 under Alan Ayers, one of the people under the Z Division group, and began working. My job, in that day, was very interesting.

At that time, the military needed to improve the statistics of bombing. The 509th [Composite Group] had moved from their place in the Marianas back to Roswell, and, at that time, the 509th would send up a B-29 bomber to Albuquerque. We had a loading pit at the end of the runway on Kirtland Field, as it was called. We would take the bombs that had been made by Group Z-8, the machine shop at Sandia, filled with concrete instead of explosives normally.

They would bring the bombs to me on a trailer. I would take them off, weigh them, get their center of gravity, get their mass moment of inertia using what’s called a torsion bar pendulum, and give them those. That information goes into the business of calculating how the bombs should fly. The moment of inertia is the thing that keeps the bomb from wiggling so much. A large moment of inertia would keep it more stable and so forth. They had to know these numbers. Well, that was one of my very early jobs at Sandia.

We were also interested in the effects of shock and vibration on various components in the bombs, so quite often, Group Z-5, the telemetering group, would put pickups in the various drop units, as they were called. We could take one of these bombs, measure its characteristics, take it or give it to the military, sign it over to them. It had to be assigned because we were giving things from the AEC to the military to use in the weapons program. It was interesting. You had to go through all the rigmarole of transfer from one organization to another. But nevertheless, we were in that process.

We would also measure then on the flight of the bomb and the impact on exactly the G-forces and things that were experienced in various components inside those drop units. One of the interesting places that we used for drop-testing was the little town of Los Lunas, only 30 miles south of Albuquerque. We could sometimes take a bomb, measure its characteristics, put it on a trailer, take it over, put it on a B-29, and rush down to the range at Los Lunas. Watch the bombs fly down, tracking them with a [inaudible] light. We could tell exactly how they flew and then analyze it and see whether they were improving their bombing results. That was one of my early jobs.

Also at that time, Sandia Field, Sandia Base in those days, was under the command of General [Leslie] Groves and under the business of the Manhattan District. At that time, the people at Sandia did not know that we were going to end up being a military arsenal or a civilization organization, so it was a very interesting time.

The housing on Sandia was primitive in those days. There was no permanent housing. A few houses were available in the older part of Kirtland, closer to downtown Albuquerque. Finally, they brought in Hanford houses, plywood houses on trailers, which were put right off the parade ground on old Sandia Base. I moved into one of those two-bedroom houses, and that was a very interesting experiment. The houses were housing at least, but they were certainly not what we would consider very good housing. It was always an effort to get more and more housing for people. Sandia was growing at that time.

During that time, Congress decided that the AEC would be formed, so we were still a very interesting base. We had civilian properties under the Manhattan Project that had to be transferred to the AEC. The military had the rest of the base. For a long time in the early days, we had MPs, military police, on both the outer gates and the outer region of Sandia. In what we called the Tech Area, the area inside that is just down the road from where we are here [at the National Museum of Nuclear Science and History], was then run by the MPs. Well, of course, eventually, when the AEC took over, the AEC got its own guard force and took over the job from the MPs.

I can remember in the very early days at Sandia – before we had any repositories – when I could go into one building in the Tech Area in Sandia and see our nuclear arsenal. At that time, the number of nuclear weapons was very, very secret, and Colonel Gil Dorland would take, as part of his job, the number of weapons we had available up to Washington and give it to the general in charge of the Manhattan Project.

We were not sure where we would end up. For a while, Sandia was run under some personnel from Johns Hopkins University. Then finally, after 1947, when the Manhattan Project was disbanded and their efforts taken over by the Defense Atomic Support Agency, DASA [misspoke: Armed Forces Special Weapons Project], who took over the operation of the base, we, of course, were wondering where we would be.

When Congress made the decision it would be civilian, we had a civilian island in this military base. As we expanded at Sandia, it was always an argument about who had which land and which land could be used for various things. Sandia, for instance, later on established an Area 3 out in the boonies out on the mesa. That, of course, came again out of the military area. One time, during my tour at Sandia later on, we had reactors out there. Pulse reactors as well as steady-state reactors. I was in that program, specifically.

It was a very interesting time, and a time when, I think, not much has been written about how things were handled. In about 1948, I decided to go back to school. I went back and took my master’s and doctorate at Yale in mechanical engineering. At that time, Sandia said they would like me to come back to work. I returned to Sandia and stayed at Sandia Laboratory in various aspects of it. Everything from shock and vibration to weapons effects on materials, and so forth. I finally worked in the WIPP [Waste Isolation Pilot Plant] Project, which is where the Department of Defense [misspoke: Energy] is finally putting the wastes that were generated during the wartime years. It’s been a tremendously interesting area.

During that time, I got interested in the work of the Museum, which was a way to display what Sandia had built. The very first museum was built on Sandia Base using one of the old military buildings right off on Wyoming Boulevard. I could go over today and look at the buildings in which the museum started. Finally, it was decided that the museum had to move out, and we didn’t have a place to move at that time. We looked around and found a building down in Old Town, and the museum moved down there.

During that time frame of the early days of the museum, the museum docents were a group of people that had become interested in the overall history of the thing. I got involved in that. Some 40, 50 years ago, I began acting as a docent at the museum, taking people on tours through the museum and studying how things developed during the time from the very early weapons, the Fat Man and the Little Boy, to the Mark IV, the Mark V, the Mark VII, all the way up to the modern weapons, which we have today.

Bare critical assembly means there’s no reflecting material around the mass of uranium-235, or it could be plutonium, but uranium is a little bit easier to use. We had a mass of material that was almost critical with ways to adjust just exactly how critical it was. We’d bring it up until it was just delayed critical. That is the point where it is reacting, but it is neither increasing in intensity nor decreasing in number of neutrons that are given off. Then, we’d drop out of what we called the safety block, which took it well below critical. When it cooled down, then, you’d insert the critical assembly again to take it back to critical and fire a little bunch of reactivity into it.

Now, Los Alamos, in their interest in tricky names, named the difference between a reactor that is just critical on delayed and prompt neutrons. The ones that are critical in prompt neutrons alone, which is a little bit bigger mass, they called that difference a dollar’s worth of reactivity. We would take one of an assembly that had been set at just prompt critical and fire a dollar and six cents’ worth of reactivity in it. It would go off, heat itself up instantaneously with the fission, and expand enough that it caused enough additional area to be moved with the neutrons leaked out of to take it below prompt critical. Still, it was above delayed critical, but we dropped that safety block out, so we’d get a burst of prompt neutrons out of this 1014 prompt neutrons, which we could then use to perform experiments on things to see whether they were sensitive to neutron bombardment. That was one of the very interesting things that I did at Sandia.

Another one was, of course, when we decided that we had to have in the United States a repository where we could put waste that had been generated during the many years, specifically many of the war years, when we weren’t very good at knowing how we should isolate things and how we should keep track of this. To take material that had become irradiated in some way and take it out of harm’s way and put it in some final repository where it would be safe. The WIPP Project, the Waste Isolation Pilot Plant, was deemed to be that. My last tour of duty, when I was still at Sandia, was working with the WIPP site. That WIPP site is down in Carlsbad, New Mexico in the depths of a salt mine some 2,000 feet underground, where we can take and – we believe safely – store nuclear waste where it will essentially never come in contact with the populations of the world again.

I remember we had a little office down on the bottom level in the WIPP repository then. I was working under Dr. Wendell Weart then, who was my department manager. We had an Albuquerque telephone line that was a direct Albuquerque line, so I could dial up anybody I wanted to talk to in Albuquerque without going through long distance, which is something that the modern generation has forgotten about! Nevertheless, it was kind of interesting.

Over the years, I’ve been terrifically interested in this business of running the museum and explaining to people things about nuclear devices. Of course, we’ve come a long way from the first Fat Man and Little Boy weapons to now thermonuclear weapons using fusion as well as fission to give us a much larger yield. Yields which are on the order of, well, a thousand times more powerful than the weapons which we dropped on Japan. Modern weapons, which we show in the museum, such as the B-83, could have easily a thousand times the yield of the weapons that were used in Hiroshima.

To me, one of the most interesting and important things that I try to talk about in my tours is nuclear fission. As we know it today, it has the potential of replacing fossil fuel energy. At the present time, we know of no other energy source that is reasonably utilized. Of course, at the present time, a great percentage of our electrical energy is generated using coal or other fossil fuels. Gas power or coal power. I’m completely in acceptance of using acceptable fuels, such as sun power and so forth, which doesn’t cost us anything in the way of contaminating the universe.

We’re always developing more efficient uses of electricity so that in some places the use of electricity has gone down in most homes today. You don’t realize because we’re using light-emitting diodes, LED lights, instead of incandescent lights, and they use one-fifth of the electrical power that we used to use in incandescent lights.

Even with advances like that, if the world is going to be supplied with electricity – and I see no other usable source of energy – I think nuclear energy must be used. I try to stress that in my telling people about nuclear energy. It’s a source of energy, and there’s enough uranium now reasonably available that for the next millennium, the next thousand years or so. Certainly the next century, we can use fossil fuels. By that time, I would hope, that we would use some other non-polluting kind of energy.

Ever since the beginning of the nuclear age – the beginning of fission, you really should say – we’ve been ten years from being able to get a fusion reactor running. That’s been going on for at least sixty or seventy years and may go on much longer. [Laughter]

I think the business of educating the public is a very important part of the museum. It’s wonderful to be able to explain the way we won the war and how the weapons were made. The work that you’ve seen recently in new development of the nuclear portions of it is very interesting, and so much more is known now. I think this has to continue, and that’s where I think we are today. I think that the museum does have a very viable job of bringing this forward to the public.

Weisenberg: When you’ve given tours here, what is sort of the most interesting or surprising fact that you like to tell people?

Ellett: Well, I think the things that have come out later in the development of things nuclear. We know now that whenever we create a new nuclear particle, we also get matter and antimatter. One of the big questions is where did the antimatter go to make the whole universe, which we believe is made up essentially of matter. Where did all the antimatter go when it was put together and came into being some 13 billion years ago? I think that’s a very interesting portion.

I think the business of just telling people that so much of the stuff that seems so very secret is just the result of getting enough minds together. [J. Robert] Oppenheimer said that things just grew. If you got chemists and nuclear engineers and mechanical engineers and electrical engineers together, the business of building a thermonuclear bomb would naturally occur because people would realize that if you irradiate thorium with a neutron, it turns into a fissionable material. If you take lithium and bombard it with neutrons, you can get tritium out of it, which is, we think, necessary to use the fusion part of getting energy. If we ever could achieve fusion, there would be no appreciable end at all to the necessary need for energy. Energy would really be something that we could give away, as was promised in the very early days of nuclear energy.

People are interested in the history of how the thing evolved, the business of taking how Hahn and Strassmann [discovered fission]. Well, to me, the beginning of the nuclear age began when the neutron was discovered by Chadwick in 1932. That same year, or just slightly ahead of that, heavy water was discovered and things like that. It was the very beginning of things, but it was realized very early that the neutron, with no charge on it, could more easily enter the nucleus of an existing atom, and people began playing around with that.

[Enrico] Fermi – long before he became famous in World War II – in 1934 was busily involved in Rome in taking all the elements and bombarding them with neutrons just to see what the heck would happen. He undoubtedly did, when he got to uranium, cause fission, but it was the brilliance of [Otto] Hahn and [Fritz] Strassmann and the analysis of Lise Meitner and Otto Frisch, working with Lise Meitner.

They came up with the idea that the neutron would enter a heavy element, because it to break it in pieces, and, when you break a very heavy element in pieces and look at the mass of all the pieces that are left over, you will find that about one part in a thousand of the mass has disappeared. That little amount of mass that disappeared is a tremendous amount. 200 million electron volts’ worth of energy.

Now, what’s an electron volt? An electron volt is a very small measure of things. If you take chemical things, like oxygen and hydrogen, and combine them to get water, you get less than 10 electron volts. Breaking this very heavy element gives you 200 million, so the point is that a tiny bit of material can give you a terrific amount of energy. It’s all because of Einstein’s famous E=mc2, where c is such a tremendously large number, three times 1010 centimeters per second. When you square it, nine times 1020 – nine with 20 zeros after it times the little tiny bit of mass – will give you an appreciable amount of energy, such that the amount of mass in a paper clip – one gram or so of mass – can give you the equivalent of 20,000 tons of TNT. That’s the amount of mass that’s actually lost in the first conventional nuclear weapons.

Weisenberg: Getting back a little bit to the early days of Sandia, do you remember of your first impressions were when you first came to Los Alamos, and then when you first came down here?

Ellett: When you first came to Los Alamos, of course, I was met at the railroad station by a man who says, “You’re in uniform. You probably want to go to Los Alamos.” He took me up to Los Alamos and got me to the badge office. I went and was immediately impressed by the little town there, which had a Tech Area with a fence around it all guarded by MPs, and so forth.

It was in this completely different – oh, visually, Los Alamos. People who come in from the East are just amazed by the clarity of the sky, the feeling that you get from living at 7,000 feet, things like that. Many people, of course, got almost altitude sickness living even at 7,000 feet, but they become quickly accustomed to it.

Almost immediately after I got there, I was shipped down to Albuquerque and put on this desolate post, Sandia Base, which was an old base with hundreds of aircraft around it, which were being cut up and melted down for their aluminum content. It’s there that the Z Division was moved from Los Alamos to allow the design of the weaponizing of the nuclear blast that Los Alamos made into weapons. Sandia Laboratory, now Sandia National Laboratory, was that facility in the early days and was the nucleus.

That’s all very interestingly described in Richard Rhodes’ book, The Making of the Atomic Bomb, which we still think is one of the most interesting books. There’s a brand new one. I don’t know whether many people have seen it, The General and the Genius. That talks about these things in a very interesting way. I’ve read that and find very few errors in it. It’s most interesting.

Weisenberg: Now I have to ask, because you mentioned that book, did you ever meet Oppenheimer or Groves?

Ellett: I never met Oppenheimer or Groves. The bombs were dropped in September [misspoke: August], and he left in October. I never personally met Oppenheimer. I saw Fermi one time. I met and worked with many people at Los Alamos. Specifically, when we were designing reactors, they were quite helpful in helping us design the burst reactors and so forth, the people up there. That was intensely interesting and got me into a whole different aspect of things nuclear.

But I think nuclear physics is just terrifically interesting. It’s growth from the time we had just neutrons and protons and electrons to the time where we’ve got all these quarks and things like that. Neutrinos and the new particles of modern physics. One of the most interesting courses I ever took was from [William L.] Davidson at Yale, who talked about the early days of the physicists and their working through the business of finding out all this business of nuclear energy.

I still think that the way to tell people about how things nuclear worked is to look at what happens when a neutron goes into various elements. You find that the elements have a very distinct loss of mass as you go from the very light elements down to the very heaviest of all elements per neutron in the coal and in the iron area. Then the mass increases again.

We have here a function of how the mass of what we call the packing fraction changes from hydrogen down to iron and up to uranium again. This curve says that if we take light elements and make heavier elements out of the components of that, we lose a tiny fraction of the mass until we get down here in the most stable of all elements. We think that’s why iron and nickel are in the core of the earth. It’s the most stable of all elements. Then it goes up again, and we get to the point over here where the very heavy elements, uranium and plutonium, if we break them apart, we lose energy because the parts are different down here.

This packing fraction turns out to give us what we call bonding energy, which says that the bonding energy that’s given up increases all the way up until you get to iron, and then decreases again. If you look at the bonding energy again, you lose about one MeV, one million electron volts, by taking a heavy element and breaking it into lighter elements. Since we’ve got slightly over 200 nucleons, neutrons and protons in the very heavy elements, that’s where the 200 million electron volts comes from that is liberated when we fission a uranium or plutonium atom.

I think that’s something that can be easily comprehended by looking at masses. Any other thing that you think you’re interested in?

Weisenberg: Interested in hearing a little bit more about some of the people that you worked with here, especially in the early days.

Ellett: Well, of course, the people in Z Division that came down from the Hill were about 200 people. I was one of them myself, although I had only a few days in Los Alamos. That early group was still very much sure that they could do so many things and make better weapons. I think, over the years, we’ve accomplished that.

I remember when I got that job assignment, there were four of us lieutenants that were sent to Sandia. Bill Moffett and I ended up in the program where we were interested in using the weapons. One of the other lieutenants was very much interested in building up our weapons under Art Machen.

The group of civilians and military that left Los Alamos that were sent to Tinian to actually put together the bombs, I worked with many of those people. They were in that group. Some of them worked for me in the drafting room. I was in charge of the drafting rooms in the early days. I couldn’t handle all these weapons on the design, the so-called 1561 designs. How they assign numbers to weapons components at Los Alamos was always interesting.

You can read in Rhodes that the weapons changed even practically while they were putting the very last weapons together. There was a 1200 series of drawings, which made this sphere, which is the one that chose the sphere that’s hanging on the display out in the museum now, showing them moving the first bomb up into the capsules at the Trinity shot. The 1561 gadget, as it was called, and all the various parts of it. The actual pieces of those bombs were extra pieces that were made in the early days of bomb manufacturing. They are definitely real, not even replicas. They’re the real parts that could have been used to assemble nuclear bombs in the early days.

It was interesting to be very much in the know at that time, although, of course, you could not talk about it. I could say today that we show and sell drawings of the various first bombs in the store here and have the 1561 nomenclature on them. That’s kind of interesting.

I worked with [James] Les Rowe and [inaudible], the people under which the first bombs were stored. I watched the growth of the weapons and the various politics of how nuclear energy should be controlled, as far as the weapons go. I, unfortunately, never really got into the business of designing reactors, although I understand reasonably well how a reactor works. Things like that.

I’ve been a member of the American Nuclear Society for more than 50 years. One of the people that has been a docent at the museum for more than 30 years, so it’s been fun and interesting.

It was very interesting working in the very early days at Sandia. That housing was pretty primitive. The Hanford housing, and to move from there to get a luxury of really a full house that stood up to the requirements for adequate officer housing and so forth on a military base. It was very interesting in the early days of the beginning of Sandia Laboratories and its growth.

Weisenberg: How long did you live in that two-bedroom?

Ellett: Oh, I think we were only there about a year before they started building the houses on the officer loops, which were then near what was then called the officer club. Then, the AEC decided they would have their own housing area, so they moved the civilians – and I was one of them – from the officer housing into the new AEC housing. About that time, I left and went back to graduate school. When I came back, things had changed. Sandia had changed from, oh, maybe 1,000 people when I left to 5,000 during those years. The years from 1949 to 1952 when I was back in graduate school.

It was interesting because when I walked into the place, it was just like going home again. To come back from Yale and come back to the dry desert. The completely different climate. I had grown up in the East in the lush vegetation, and here, even in a very wet season, which you see today, it looks very brown to the Easterners who see it.

Weisenberg: Have you lived in Albuquerque ever since?

Ellett: Yes, I have lived in Albuquerque from 1952 to the present time. When I got to Albuquerque in 1946, it was boasting a population of 50,000. There’s more than a half a million people now in the metropolitan area of Albuquerque. That’s a tremendous thing. There were dirt roads between here. Many dirt roads. 66 was the only paved road. There were some paved roads in Sandia Base and Kirtland then because the two had different names.

Well, I remember going down to the University of New Mexico and going down Lomas Boulevard when it was nothing but a dirt road from out here down. We went the back way, Jack Howard and I. He was one of the vice presidents at Sandia. We were taking a course down there one time.

In my various reserve requirements, you had to take officer courses where you learned – junior officer courses, then senior officer courses. Then, I took the command and general staff course, where they, at Fort Leavenworth, showed us finally with a great demonstration. I guess this was in the ‘60s or something. They showed us a Mark VII.

I could tell people how it worked and so much more about the nuclear part of it. When, if you get a super critical condition existing in a mass of material, the neutron goes up maybe 2, 4, 8, 16, 32, 64, 128, 256, 512, 1,000, you know. 80 generations of this take less than a millisecond to do.

The business of making a nuclear explosion is a very interesting and very well-known thing now. It was the brilliance of some of the Los Alamos people who decided that we could take a fission bomb and use it as a source to compress the material in a fusion bomb to make it go off.

Stanislaw Ulam had that brilliant idea that he could use the fission bomb to support the tremendous compression of material, so that we reach the ignition point of a mixture of deuterium and tritium to give us a nuclear explosion.

Of course, the early fission bombs were really fission/fusion/fission bombs. The fusion part of it was not as much as people realize. When you fuse hydrogen, the neutrons coming off of that will fusion U-238, so the last fission portion of the fission/fusion bomb is the business of fissioning the U-238, which is normally considered un-fissionable material. Just the idea that you use so much nuclear physics in a bomb, and it just happened that way and worked. The idea of a pure neutron bomb is sort of a misnomer. Nobody can really make a neutron bomb. It’s a fission bomb that’s designed, so it accentuates the number of neutrons. It does not make purely neutrons. I don’t think many people realize that now.

Teller was a very impressive guy. I’ve seen Teller again in my work at Sandia, although I was never involved in that portion of the work. He had a hundred ideas a day, only one of which was really good, maybe. The way he worked things was he always wanted to go to a new project before he completed them. I think that’s so well brought out in the various studies of how the nuclear weapons were designed in the work of Richard Rhodes and others in documenting that. I think it was very interesting.

Weisenberg: Are there other jobs that you held at Sandia, or other stories from your time here that you want to share?

Ellett: It just was an extremely exciting place to work at, to realize that things were going along. Really, I think the business of following the changes that occurred over the years and the fact that so much of this is declassified. I think one of the interesting things is that there’s enough known about how to make a nuclear bomb – the earlier nuclear weapons, especially – that any county in the world that has the money can build a nuclear weapon. I think that’s been shown. How many countries in the world today now have or have had nuclear weapons. Of course, the United States, Russia, Great Britain, France. I’m sure that Iran will be able to make a nuclear weapon. There’s no question about it. Enough is known.

We try to keep as much of that out of hands. I don’t think any small group—it takes a tremendous amount of infrastructure to build a nuclear weapon. Nobody can build one in their garage. If they could get the nuclear material, maybe they could do it in their garage, but the business of making the nuclear material and setting up the whole process is a very complex process that the people at Los Alamos and Livermore, and so forth, have done successfully over the years.

Certainly, there’s no doubt that Russia – and earlier as the USSR or as present-day – has the capability of making bombs. I just hope that they are never used for the wrong purposes. What is the best policy is far from my ability to discern, but I think we’ve done a reasonable job in the United States today.

Weisenberg: Are there any other questions or stories that come to mind?

Ellett: Well, [Richard] Feynman, of course, was a practical joker, and I think it’s a story that’s repeated in Rhodes’ book. He found out that there was a hole in the fence at Los Alamos around the Tech Area, so he would go into the Tech Area, and he’d go out that hole, come around and go in the gates again. The guy said, “You haven’t come out yet!” He completely confused him by doing that. He was a great jokester, and he was a brilliant man. Quite an interesting life, of course.

The safes, as they normally came from manufacturers – of course, everything was protected in safes when I was at Sandia, and you needed the three numbers on them to use them. He learned those. He knew that was the normal process. Many of the secretaries never really got around to changing their safes out, and then people would forget what the numbers were. He would come in, and Feynman got the reputation of being a tremendous safecracker because simply he had observed enough and stored enough in his mind that he could use these little tricks that a good safe man really knows. He would come operate a safe with that.

The early safes – when you’d dial the right combination, there was a little click when some of the critical pieces fell into the correct slots on the combination. If you’ve ever looked at a combination lock for a safe. He learned that by learning such tricks, which modern locksmiths know now, he could crack many safes at Los Alamos and just got notorious by being able to open anything at Los Alamos, which I’m sure is not really true. He was a prankster.

There’s pictures in Rhodes’ books of a bunch of scientists together pulling an old car out of a mudhole at Los Alamos. The caliche that we have in this area, when it becomes a mud, is just the stickiest and slimiest stuff imaginable. Even a very well-educated man could get stuck in the mudhole and have to get his Ph.D. friends to help push him out. That was always a very interesting position. A turnabout from a man with a Ph.D. down in mud up to his calves trying to push a car out of a mudhole with a Ph.D. driving it. So much for that.

I think the most interesting thing to me is still living through the time when we were developing in the United States a nuclear policy. Who would govern it, who would own it, who would have the permission to fire a nuclear weapon. It still at the present time, I think, requires a presidential decision to use a nuclear weapon. I think that’s still a viable and reasonable thing.

Weisenberg: One other question I had was about the secrecy and security. There was a lot of compartmentalization. But you were there [at Los Alamos] and then down here after the war, so were you more free to talk about what you were working on with your colleagues? Or was it still a lot of security?

Ellett: Our main guide in the early days was, of course, that book published under General Groves, written by a professor, who is it—

Weisenberg: [Henry DeWolf] Smyth.

Ellett: Smyth. The Smyth Report. Anything that was in the Smyth Report could be talked about, but you couldn’t expand on that. That was the general rule. Of course, there was always a very fuzzy area.

Charlie Schmidt had a book that listed all the weapons that Sandia had actually made into devices. He wanted to put photographs of them all. Every one had been photographed, but simply to get a book, which had all the pictures and all the photographs. The people in classification decided that was classified and could not be published. Where to draw the line is always a question.

So much is known now that you have to have computer programs, very advanced degrees, lots of infrastructure to really make any changes and do things. I think we’re still doing a reasonable job, although I’m sure that it’s always been argued that every man has his price. Somewhere in the group of things there’s a person who was willing to take classified material and try to sell it for his own gain. I think that’s hard to argue with.

Weisenberg: Is there anything I haven’t asked you so far that I should have asked you?

Ellett: Not really. I think things like the latest design, the latest display that we have on the critical portions of the early weapons out here is reasonable now. If you look, with knowing in the background, at the pages in Rhodes’ books, you can see things that probably should have not been put in there because they might have been considered classified.

Weisenberg: That’s interesting.

Ellett: Well, the business – that is well-known today – that you can take a solid material and if you have high-enough pressures, you can actually compress it. When you compress it, you lower the distance between the atoms, and you can take something that is not fissionable in the normal sense it’s below critical mass – and compress it into something that is fissionable. That is one of the things that, of course, is well-known today. That was not publicized at all in the early days. It slowly leaked out, and when the Rhodes’ book shows you a picture of some of the X-ray experiments at Sandia, where they took explosives and compressed solid materials, maybe close on being classified.

The equations of state, I’m sure, are still not completely known on materials. That was the very interesting point. How just exactly, if you have enough computational process, you can inch in on very classified things.

One of my jobs was trying to follow the effects of the nuclear weapons that were put off on the [Nevada] Test Site on the surrounding population. Whether or not when a bomb went off on the Las Vegas site, and people in the nearby communities would say, “You broke my windows,” or, “You caused my building to crack,” or so forth. Whether or not that was reasonable. That work was done with the John A. Blume organization of San Francisco. John A. Blume was a very interesting organization.

Just the fact that the work that we did on the test site, where we had nuclear explosions that would give us a certain magnitude earthquake, let us learn a great deal. A great deal of information was learned during the test site that was on the effect of earthquakes on conventional buildings. I thought it was very interesting. We made a two-megaton bomb and, buried at optimal depth so it wouldn’t breach, is essentially a magnitude 6 earthquake. There were two-megaton bombs set off, and we had buildings that we instrumented to see the response of buildings to a known source. It was very interesting to be able to cause your own earthquakes.

Weisenberg: When you were doing this, were you going around and interviewing people?

Ellett: Well, you look at damage reports. That’s what you do. You try to ascertain whether it’s legitimate or not. You want to protect the United States from being sued for things that weren’t really their fault. You also wanted to compensate people for destruction that you actually caused on their property. That was sort of an interesting era, and one of the things that I worked in for many years.

Weisenberg: What did you find out, what did you learn, while you were doing this?

Ellett: Oh, many things. If you look at an earthquake, the natural period of an earthquake is dependent upon the number of stories it [a building] has. Roughly speaking, in many instances, it has about a tenth of a second to the natural period for every floor that you have. If you have a 10-story building, the natural frequency of the building is apt to be in the neighborhood of one second. Because you’ve got 10 tenths of a second up to it. A 20-story building might be two seconds. The taller the building, the longer. Shock and vibration is a very interesting thing, and that’s one of the things that I did work in many years. I was Secretary of the Shock and Vibration Symposia for years in the United States.

Weisenberg: So you would go out to Nevada from here fairly frequently then.

Ellett: Well, we would have the John A. Blume go out and investigate for us. They were contractors for us. I was the officer at Sandia who was responsible for looking at the performance of those contracts. You naturally found a lot of interesting things about earthquakes. You better had tie your buildings down, for instance. That if you built a frame building and didn’t bolt it to the foundations with enough bolts – that you sheared the bolts – then you really caused problems. Things like that, just general engineering. Well, one of my cohorts wrote a book, Safety in Earthquake Country, that gave us a reasonable criteria for improving the ability of a building to withstand earthquakes. That was totally interesting.

Ellett: Over the years, Sandia has been investigating an intern program, where we take young engineers and run them around through talking to the people who were in the process of developing the expertise that we have today, so that we don’t go out and make square wheels again. That was really what it was. To show people what’s been done in the past and to bring them up-to-date on what has been done. That, to me, is one of the very interesting programs. The interns almost always have a very good time coming through the museum and seeing our Fat Man and Little Boy and our illustrations and being able to tell them what we did in the early days.

Ellett: One of the blasts that I saw was a high-altitude blast out at the Nevada Test Site. It reminded me of standing before a furnace and having someone open the door and feel the heat on your face. You being 10 miles, 15 miles away from the blast. It was fairly small. I don’t know. A few kilotons, I think. It wasn’t a very large blast, but the heat from a nuclear blast is really quite amazing.

Weisenberg: Do you remember what shot or what test series that was?

Ellett: Oh, gee whiz. No, I don’t. But it was a high-altitude, HA test. We took a B-36 and flew it as high as we could and dropped a bomb, or on a parachute until the plane can get away and then detonated it, so that it wouldn’t blow up the plane. It couldn’t be a very big shot because they didn’t want to blow up the B-36. A B-36 could get up to, I think, about 36,000 feet, so you had to slow it down for the burst because it was detonated, I think, at close to 30,000 feet. We wanted to see the effects at high altitude. I think the code name of the test was HA: high-altitude.

It was just a very interesting blast. To be able to go out and know when it was going to happen was sort of interesting. Then, of course, a tremendous amount of time. Since sound travels at only – it takes five seconds to go a mile – and you’re miles and miles away. One minute later or so, the blast noise. That was reinforced by the people who saw the first Trinity shot. They saw the blast, and then, minutes later, they heard the rumbles that just seemed to forever go on for them. It’s an amazing thing.

Just to go into an underground blast. I was [inaudible] up in Colorado when we were thinking about using nuclear blasts to break up rock formations, so that we could extract oil. The same business that we’re using now to get natural gas from deep installations with hydraulic pressure. We were thinking about using nuclear explosions, but that was not a very good idea. People did not like the idea that nuclear gas had been produced as a result of a nuclear explosion, so the idea under Project Plowshare just sort of faded away.

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