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Countdown to The Cold War: Inside the B-17 (Photos!) May 27, 2015

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On May 10, Anna flew in a B-24, and Doug flew in a B-17. Both aircraft are part of the Collings Foundation’s tour and stopped at Lyon Air Museum. This week, we share the view from inside the B-17 Nine-O-Nine during a flight along the California coast.











Countdown to The Cold War: B-17 Flying Fortress (Videos) May 20, 2015

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On May 10, Anna flew on a B-24. Doug flew on the B-17 during its stop at the Lyon Air Museum. If you’re interested in seeing these aircraft, check the Collings Foundation SCHEDULE. If you can’t see them in person, here are videos from Doug’s B-17 ride.

Though the Collings Foundation’s B-17 was built in April 1945 and, therefore, didn’t see combat, it has been designated as Nine-O-Nine, an aircraft that flew 140 combat missions. In 1952, the aircraft that we saw at the Lyon Air Museum was part of three nuclear weapons effects tests. After it was deemed sufficiently cooled down thirteen years later, it was refurbished and was used to fight forest fires. In 1987, during an airshow, the B-17 was caught by a crosswind just after touching down and crashed, with no loss of life but significant damage to the aircraft. Once again, the plane was restored and has been touring the country.

The original Nine-O-Nine started flying missions in February 1944. The aircraft’s first bombing run was against Augsburg, Germany. In the end, it flew more than a thousand hours and dropped more than a half-million pounds of bombs. The aircraft flew back to the United States in June 1945 and was eventually scrapped with other leftover planes.

Next week, check back for some amazing photos we took of and from the B-24 and B-17!

Countdown to The Cold War: B-24 Liberator (Videos) May 13, 2015

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Last week, May 8 marked the 70th anniversary of V-E Day. In 1945, the war in Europe officially ended with the signing of the act of surrender on May 7 in France and May 8 in Germany. The war in the Pacific Theater waged on.

B-24 Takeoff

In August 1944, a Consolidated B-24 was built. By October, it had been delivered to the U.S. Air Force, which then transferred it to the Royal Air Force. The RAF flew this B-24 in the Pacific Theater until the war there ended and it, along with a slew of other aircraft, was abandoned in India. The Indian Air Force restored it in 1948, and flew these restored aircraft for twenty years. After that, it was abandoned again, until a British aircraft collector took it apart and transported it back to England in 1981, then sold it to Dr. Robert F. Collings a few years later. After more than five years of restoration work, the B-24 flew again. In 2005, it was repainted as Witchcraft, another B-24 that had flown 130 combat missions but had long ago been scrapped.

B-24 Cockpit in Flight

On Sunday, May 10, 2015, we drove over to our local aviation museum, the Lyon Air Museum. There, Anna crawled into this B-24, strapped herself down under the waist gun, and took a half-hour ride. In this post, we share the experience through videos so you can take the ride too.

B-24 Tail Gun in Flight

The flight couldn’t go on forever, but Anna could have stayed up another half-hour at least.

B-24 Approach & Landing

Countdown to The Cold War: Aircraft of WWII April 29, 2015

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Doug’s Mom sent us a packet…


…filled with photographs of World War II aircraft:











Countdown to The Cold War: February 1945 February 18, 2015

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The Guard at the gate on The Hill, checking IDs

The Guard at the gate on The Hill, checking IDs

In February 1945, the end of war in the European theatre of operations was still a few months off in the future. Nonetheless, Allied leaders felt that the war’s end was close enough that they could begin to anticipate the post-war era. To that end, Churchill, Roosevelt, and Stalin met in Yalta—a city on the Crimean peninsula overlooking the Black Sea—on February 4-11 to discuss the shape of post-war Europe. Because of the tense relations between the United States and Britain on one hand and the Soviet Union on the other, which were reinforced during the meetings, the Yalta Conference is the oft-cited start of the Cold War.

In our “Countdown to the Cold War: October 1944” post, we detailed the struggles associated with the Hanford nuclear reactors, then known as atomic piles. In the last months of 1944 and in January 1945, engineers and scientists working on Hanford’s problems ironed out the kinks of the plutonium production process. Sometime between February 2th and 7th—sources vary on the exact date—the first weapons grade plutonium began making its way from Hanford to Los Alamos.

In the book, Hanford and the Bomb: An Oral History of World War II, author S. L. Sanger has this to say about the event:

[T]he first Hanford-produced plutonium was handed over by Du Pont to the Army. The next morning, Col. F.T. Matthias took it to Portland by car with a military intelligence escort. From there, Matthias and an agent went by train to Los Angeles where the package was given to an officer from Los Alamos. Matthias described the container as a wooden box wrapped in brown paper about 14 inches on a side and 18 inches high. It had a carrying handle and the syrupy plutonium, weighing about 100 grams, was carried in a flask suspended between shock absorbers.

The next time you’re about to board an airplane and TSA agents in the security area shout reminders of the restriction to 3-ounce containers of liquids and gels, think about how times have changed. During World War II, one of the most hazardous substances ever present on the face of the earth was carried on a regular passenger train. In a wooden box. Wrapped in brown paper.

Hanford 1960

Hanford 1960

Sanger’s book describes the meeting between Matthias and the officer from Los Alamos in what was almost certainly Los Angeles’s Union Passenger Terminal. Apparently, Matthias discovered that the officer was traveling back to Los Alamos in an upper berth, a means of rail travel that had privacy by means of curtains, but no real security, not even a door. Matthias discovered that the officer didn’t know what exactly he was being entrusted to carry back to Los Alamos. Matthias told the officer that it cost $350 million to produce the item and suggested to the man that he get a compartment with a locking door. The man did as Matthias instructed.

As revealed in to Critical Assembly by Lillian Hoddesson, et al., the Los Alamos contingent was very pessimistic about the quality and amount of the plutonium that they expected to receive from Hanford: “Oppenheimer was not optimistic about the ease of interacting with Hanford.” Ultimately, the quality and quantity of the Hanford plutonium was deemed sufficient to carry out the metallurgical research necessary so that plutonium could be used in the Fat Man weapon.

While the arrival of the Hanford plutonium in February 1945 was a huge event in the run-up to the Trinity test of a Fat Man type of atomic weapon, other activities related to Fat Man were taking place at Los Alamos at the time as well.

J. Robert Oppenheimer, Anna, General Leslie Groves

J. Robert Oppenheimer, Anna, General Leslie Groves

In December 1944, several new advisory boards and standing committees were created at Los Alamos. Chaired by physicist Samuel K. Allison, the Technical and Scheduling Conference was responsible for oversight and coordination of the transition from research to implementation. On Saturday, February 17, the Technical and Scheduling Conference met for four hours to discuss competing designs for the Fat Man-type weapon.

J. Robert Oppenheimer, the Manhattan Project’s director, argued throughout the day for simpler, more conservative design decisions. As Bruce Cameron Reed describes it in his excellent book The History and Science of the Manhattan Project, the final outcome of that committee meeting wouldn’t be decided until an end-of-the-month visit by General Leslie Groves:

On February 28, just eleven days after the TSC meeting, Oppenheimer and Groves decided provisionally on the Christy-core design with explosive lenses made of Comp B and Baratol. Characteristic of so many decisions in the Manhattan Project, their choice was a gamble: few implosion lenses had by then been tested[…].

With this end-of-February meeting between Groves and Oppenheimer, the design for the Trinity test was effectively fixed, and the lab could then focus on fashioning the numerous technologies into the world’s first atomi

Lyon Air Museum (Photos!) February 11, 2015

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Lyon Air Museum, founded by Major General William Lyon and opened in 2009, is our local aviation museum. It’s located just across the runways from the terminals at John Wayne Airport in Santa Ana, and it’s open 10am-4pm every day except Thanksgiving and Christmas. On March 9, at 10am, the museum will open the cockpit of their Douglas DC-3 flagship. On March 21, at 10:30am, Tuskegee Airmen will share their stories.

We finally made our first visit this past weekend. We’re sure to go back, and here’s why.

What’s there?

  • 7 aircraft
  • 8 automobiles (General Lyon is a long-time collector!)
  • lots of motorcycles

It’s small, incredibly well kept, and filled with surprising treasures. And planes are taking off and landing just outside the windows. Here’s a sampling of what we saw.

This C-47 saw D-Day. It was redone as a DC-3 after General Lyon sold his regional airline, AirCal, to American.

This C-47 saw D-Day. It was redone as a DC-3 after General Lyon sold his regional airline, AirCal, to American. That’s a yellow Buick next to it.

Here's the C-47.

Here’s the C-47.


B-17 with motorcycle in foreground. Note the three chairs and screen for viewing two short features, one on flying the B-17 and the other about the Memphis Belle.





Norden Bombsight

Norden Bombsight

Hot the red video "start" button, then look into the Norden bombsight to be the bombardier on a mission.

Hit the red video “start” button, then look into the Norden bombsight to be the bombardier on a mission.

One of actor Steve McQueen's former motorcycles.

One of actor Steve McQueen’s former motorcycles.

From a balcony, visitors can overlook the exhibit hall. Note the museum's proximity to the runway, with a Southwest Airlines flight taking off just outside. The noise of the active runway brings the static displays to life in the mind.

From a balcony, visitors can overlook the exhibit hall. Note the museum’s proximity to the runway, with a Southwest Airlines flight taking off just outside. The noise of the active runway brings the static displays to life in the mind.

Countdown to the Cold War: September 1944 September 24, 2014

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In the last couple of posts, we’ve begun our Countdown to the Cold War by talking about the reorganized at Los Alamos in the fall of 1944 to develop a method known as implosion. You can read the last post in the series by clicking HERE.

Handling Radiolanthanum

Handling Radiolanthanum

The next step on the Manhattan Project’s Countdown to the Cold War occurred on September 22, 1944, and was known as the RaLa experiment. Very early in the implosion research program, it became obvious that being able to systematically verify the success or failure of implosion would be a crucial measure for success. But very few experimental measures of implosion existed at the time.

In particular, for a successful atomic weapon, it was imperative that the scientists be able to engineer a symmetric implosion. Early attempts at creating implosion revealed a wide range of asymmetric behaviors that scattered material unevenly. In order to measure the symmetry of implosion, it became necessary to observe implosion events with instruments. One technique that was developed for observing implosion was known as RaLa.

Robert Server

Robert Server

RaLa is a shorthand for the active ingredient in a RaLa test: radiolanthanum. Radiolanthanum (La-140) is a manmade radioactive isotope of lanthanum. According to Critical Assembly (by Hoddesson, et al), Robert Serber first outlined what would become the RaLa method on November 1, 1943. Serber was arguably Robert Oppenheimer’s right-hand man at Los Alamos and someone familiar to folks there for the Los Alamos Primer, the introductory lectures that kicked off the Manhattan Project’s bomb design effort.

The RaLa method depended upon the use of gamma radiation given off by the radiolanthanum isotope. Gamma radiation—or just gamma rays—are a very energetic type of electromagnetic radiation. The EPA.gov website devoted to radiation protection has this to say about gamma rays:

Gamma photons have about 10,000 times as much energy as the photons in the visible range of the electromagnetic spectrum. Gamma photons have no mass and no electrical charge. The are pure electromagnetic energy.

Highly energetic gamma rays travel at the speed of light and easily pass through most materials. It is this set of properties that made them useful in characterizing the implosion necessary for setting off an atomic bomb.

Welcome to Los Alamos Today

Welcome to Los Alamos Today

Serber hypothesized that by placing an amount of radiolanthanum in the center of the metal sphere to be compressed by implosion, the strength of the gamma rays emitted during that implosion would vary in such a way that the scientists could use instruments to understand how symmetrical the implosion was. Serber knew that, as an implosion event progressed in a metallic core (uranium or plutonium for the atom bomb), there would be significant changes in the density of the material being compressed. These changes in density would retard the gamma rays in predictable ways. In addition, because the gamma rays would radiate out from the center of the sphere, the scientists would be able to collect information about the implosion in three physical dimensions.

Ta-dah, RaLa!

Given that the radiolanthanum material would be at the center of an explosion, there would of course be radioactive debris and dispersal of that debris. Gamma radiation is ionizing—releases electrons—and therefore has biological implications, meaning that it affects human bodies. And because gamma rays penetrate materials, they can be very dangerous. In this way, the RaLa experiments constitute the world’s first production of radioactive fallout, a waft of the Cold War to come. In order to minimize human exposure to the radiation that would be released, the RaLa experiments were held offsite in Bayo Canyon, located about two miles east of Los Alamos—a sort of lab away from lab. Checking the wind direction or measuring fallout, however, weren’t much a priority for these early radioactive test explosions.

Countdown to The Cold War: August 1944 (3) September 10, 2014

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In our post two weeks ago, we mentioned implosion as an assembly method for a critical mass. The critical mass is the amount of fissile material—in the form of uranium or plutonium—necessary to set-up the uncontrolled fission chain reaction that’s at the heart of a nuclear weapon. Implosion was one of three original assembly methods evaluated during the Manhattan Project: autocatalysis, the gun method, and implosion. The scientists at Los Alamos, however, had no experience using explosives to systematically create the symmetric, spherical blast wave necessary to compress solid materials for implosion. Indeed, in one of the official histories of the Manhattan Project, David Hawkins says the following:

[T]he behavior of solid matter under the thermodynamical conditions created by an implosion went far beyond current laboratory experience. As even its name implies, the implosion seemed “against nature.”

Physicist Seth Neddermeyer was an early advocate of the implosion method, and he began a serious investigation of the process in 1943. By mid-1944, because of plutonium’s propensity for spontaneous fission, it became clearer that, if there was to be an atomic bomb that used plutonium, then implosion was the only viable assembly method. The progress that Neddermeyer’s team had made on the implosion problem was deemed to be inadequate, though, and Neddermeyer was replaced. The realization that implosion was an extremely complicated problem set off a reorganization of Los Alamos that saw the creation of entirely new research groups, promotion or hiring of scientists to lead those groups, and realignment within existing research groups.

Doug with Oppenheimer & Leslie Groves

Doug with Oppenheimer & Leslie Groves

What’s remarkable about the Los Alamos reorganization is the breadth of the changes and the speed with which they were executed in the fall of 1944. A letter in mid-June, a series of meetings in July, and final approval on July 20th, 1944—1, 2, 3, go. The changes required by the reorganization were considered to be in effect on August 14th, 1944. The gun design was considered to be making acceptable progress under the leadership of Navy Captain William “Deak” Parsons. Parsons had been in charge of the Ordnance Division, and perhaps the biggest change that underwent was becoming the O Division. The two most important of the newly created divisions were X Division and G Division. X Division—X for Explosives—was headed by Harvard physical chemist George Kistiakowsky. Kisti’s group was responsible for every engineering and development aspect of creating the explosive system used to render the implosion. G Division—G for Gadget—was led by Robert Bacher and became responsible for all of the aspects of the bomb that had to do with its nuclear core, the so-called plutonium pit. In addition, because of G Division’s responsibility for the pit, they were also charged with developing various experimental methodologies for evaluating the effectiveness of the implosion—in particular, measure for validating the compression of solid materials. Trinity_explosion2Importantly, the series of organizational changes that enhanced the overall understanding of the implosion-based atomic bomb. So, existing divisions such as R Division (Research, the Experimental Physics Division prior to the reorganization) and T Division (Theory) adjusted as the focus on implosion took hold across the laboratory at Los Alamos.

The Manhattan Project’s leadership, spurred on by J. Robert Oppenheimer, saw a problem and worked effectively to address that problem. This speedy, drastic effort that reorganized the Manhattan Project reminds us of an engineering analogy that used to come up in computer systems development: replacing a car’s engine as you’re going down the highway at 70 mile per hour. Just over two months time elapsed from the proposed changes to their implementation, with research continuing all the while. The development of the implosion device, the Gadget, was the primary focus of the laboratory from this reorganization in August 1944 until the Trinity test of the first atomic weapon on July 16, 1945. The Countdown to the Cold War was well underway 70 years ago today.

Countdown to The Cold War: August 1944 (2) August 27, 2014

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Trinity_explosion2Our first “Countdown to The Cold War” post appeared LAST WEEK, so you may want to start there.

In the vernacular of the Manhattan Project scientists and engineers, assembly is the process of transforming a subcritical mass of either uranium or plutonium into a supercritical mass, an uncontrolled nuclear chain reaction resulting in an explosion. In the earliest days of the project, most of the effort was spent on developing what was called the gun-type assembly method. This is essentially the act of slamming together two subcritical masses by firing one at the other. As a means of setting off an atomic explosion, this process has always struck the Lofty Duo as the equivalent of one of our very distant ancestors stumbling across two stones, banging them together, and wiping out the entire forest in which they lived.

The initial designs for a gun-type weapon were essentially navy cannons with one end containing a near-critical mass of fissionable to be shot at from the other end by a smaller mass of fissionable material. The first attempts were thought to require a ten-thousand pound, seventeen-foot long cannon. These designs were known as the Thin Man, after the Dashiell Hammett novel of the same name.


U.S. Government photo of Thin Man-type bomb casings

Scientists and engineers hoped that this design would work for both uranium and plutonium. While enriched uranium–enrichment being the process used to increase the proportion of desirable U-235 vs. undesirable U-238 in a given amount of uranium (see last week’s post)–had suitable physical properties for a gun-type weapon, the enrichment process was complex and expensive. During the Manhattan Project, electromagnetic separation, thermal diffusion, and, to a lesser extent, gas centrifugation were all used as enrichment processes. In fact, these processes of enriching uranium were so difficult that there were serious questions about whether enough uranium could be produced to build a bomb.

Plutonium, on the other hand, could be produced by transmuting–transmuting being changing one element or isotope into another–uranium in nuclear reactors (atomic piles at the time). Once produced, its purification and separation could be handled chemically, as opposed to the complicated means necessary for uranium. Plutonium is a fiendish metal to manipulate, and its been called the most dangerous substance known to humankind. In the early days of the Manhattan Project, it was also in short supply. As more of it became available in April 1944 and subjected to experiment, scientists at Los Alamos, particularly physicist Emilio Segrè and his group, discovered that reactor-produced plutonium (as opposed to previous plutonium samples which had been created in cyclotrons) suffered from an alarming problem.

As Segrè and his group discovered in their Forrest Service cabin deep in Pajarito Canyon, the plutonium produced in atomic piles has two isotopes: Pu-239 and Pu-240. The presence of the second isotope, Pu-240, caused the plutonium that Los Alamos was receiving to undergo spontaneous fission. In nature, fissionable elements can also undergo nuclear reaction known as spontaneous fission. This process is a somewhat different process than when nuclear fission is artificially induced through the use of a neutron. Richard Rhodes in his Pulitzer Prize Winning tome, The Making of the Atomic Bomb, gives a footnote definition of spontaneous fission: “a relatively rare nuclear event, differs from fission caused by neutron bombardment; it occurs without outside stimulus as a natural consequence of the instability of heavy nuclei.” Spontaneous was not what the Manhattan Project wanted in its nuclear material.

Emilio Segrè's identification badge, Las Alamos National Laboratory

Emilio Segrè’s identification badge, Las Alamos National Laboratory

The unplanned for nuclear reaction was occurring to such an extent that, as two subcritical pieces of plutonium were brought in proximity to one another, the assembling mass of plutonium would be subject to pre-detonation. In short, the plutonium produced in Hanford’s reactors couldn’t be used in a gun-type assembly method. So the scientists and engineers needed to figure out what kind of bomb assembly would work if they wanted to use plutonium.

It was relatively quickly realized that, in order to make use of plutonium and to avoid pre-detonation, the subcritical mass would have to be assembled fast. Very fast. The only method that was available to Los Alamos was implosion. We’ll discuss that and its implications for the Manhattan Project next in our “Countdown to The Cold War.”

In the meantime, for more on uranium, plutonium, and fission, see our post called “Uranium & Plutonium & Fission.”

Countdown to The Cold War: August 1944 August 20, 2014

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Welcome to Los Alamos Today

Welcome to Los Alamos Today

Over the last few years, your Lofty Duo has had an inordinate amount of interest in the Manhattan Project. If you were to draw a Venn diagram of our many overlapping interests in this historical event, it’s likely that somewhere in the shaded region at the center of the diagram would be a man named Henry Cullen. Henry was Anna’s grandfather. In his professional life, he was a Pullman Conductor on the Santa Fe Chief. The stories that Henry told about his train dropping off men with foreign-sounding names and accents in-the-middle-of-nowhere New Mexico are a part of Anna’s family lore.

That middle-of-nowhere spot was Lamy, New Mexico, situated about ten miles south of Santa Fe. During the years 1943-1945, the Lamy railway station was the disembarkation point for thousands of American scientists, engineers, soldiers, and their families as they made their way to the heart of the Manhattan Project: Site Y, more popularly known as Los Alamos. Site Y was one of the thirty locations that made up the Manhattan Engineer District, an administrative organization for the atomic bomb project that was created within the Army Corps of Engineers.


Trinity: First Atomic Weapon

The military director of the Manhattan Engineer District was General Leslie M. Groves, who received the assignment to manage the Manhattan Engineer District as a result of his success with building the Pentagon. As Groves contemplated the necessity of moving so many valuable technical people around the country, he became concerned by the possibility of airplane crashes. As a result, trains like the Santa Fe Chief became the primary mode of cross-country transportation for the people working on the Manhattan Project. If it weren’t for the General’s fears, it’s unlikely that Henry Cullen would have crossed paths with so many individuals who were in the process of changing the course of history.

Henry Cullen’s outsider-looking-in stories about the then secret world of the Manhattan Project have given rise to a number of projects here at Lofty Ambitions. We’ve made trips to Santa Fe and Los Alamos numerous times. We’ve visited a number of atomic-themed museums. And we’re academics, so we’ve turned what we learned into conference papers and presentations. Doug is also using parts of Henry’s story in the novel he’s writing this summer.

Building Atomic Vegas, Atomic Testing Museum

Building Atomic Vegas, Atomic Testing Museum

As we mentioned earlier this month, over the next year, we’re going to be taking a look at the last year (August 1944-1945) of the Manhattan Project. Our starting point is a sequence of events that led to a massive reorganization of the laboratory at Site Y seventy years ago in August of 1944. That reorganization centered on a new design, a new model for the atomic bomb called implosion. This new design was necessary in order for the project to make use of the element plutonium, about which we’ve written. To understand this shift in August 1944, it’s helpful to keep in mind how the Manhattan Project scientists had initially thought they might go about designing an atomic bomb.

Hungarian physicist Leo Szilard is the scientist credited for first recognizing the possibility of using the energy released by the splitting of an atom—the process of nuclear fission—to create a weapon. In the late 1930s, much of the research in the area of nuclear fission was focused on the radioactive element uranium.

In uranium, the fission process begins with the absorption of a neutron (a subatomic particle with no electric charge, and one of the three constituents of atoms along with electrons and protons). This new neutron introduced to the uranium atom adds to the protons and neutrons in the nucleus, a process that excites the atom and makes it unstable. As a result of this instability, the uranium atom breaks apart into lighter elements (krypton and barium), three more neutrons, and energy.

Replica of The Gadget at NMNSH

Replica of the first atomic bomb at the National Museum of Nuclear Science and History

However, this set of byproducts is the result of the fission in a specific uranium isotope, U-235. Naturally occurring uranium has two isotopes: U-235 and U-238. The element uranium has 92 protons in its nucleus. Isotopes are alternative configurations of a chemical element that differ in the number of neutrons in the nucleus. U-235 has 143 neutrons in its nucleus, and U-238 has 146 neutrons. The number after the chemical symbol—235 or 238—indicates the total number of protons and neutrons for that isotope (e.g., U-235: 92 + 143 = 235).

The nuclear fission that described above for U-235 releases three new neutrons. Each of those neutrons can then go on to fission more uranium atoms. As this process repeats cycle after cycle, it produces what is known as a chain reaction. In nuclear engineering, a controlled chain reaction is a nuclear reactor, a machine that can be used to generate power. An uncontrolled chain reaction is a weapon, and that was the goal of the Manhattan Project. Get that fission started and let it run wild.

U-238, the other naturally occurring isotope of uranium, has a nuclear reaction that generates only a single new neutron. So, one neutron is needed to cause fission, and one neutron is produced by the fission. That’s just not enough to sustain a chain reaction. So the Manhattan Project needed U-235.

Train Station at Lamy, NM

Train Station at Lamy, NM

Naturally occurring uranium, however, is found in an isotope mix that is 99.3% U-238 (which the scientists and engineers didn’t want) and about 0.7% U-235 (which was what they did want). They worked as best they could with this situation of separating out the isotope they wanted. As their work proceeded, though, they wondered whether plutonium might be used instead of uranium. As they began to think about how plutonium might work, they realized that the bomb design under development for uranium wasn’t suitable for using plutonium.

So while the Manhattan Project continued to pursue a weapon that used uranium, they refocused efforts on plutonium and began developing another design.

For the next post in “Countdown to the Cold War,” click HERE.


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