The Manhattan Project, An Interactive History Home The Manhattan Project, An Interactive History Home Department of Energy Home Office of History and Heritage Resources Home DOEHome
J.R. Oppenheimer and General Groves
Events People Places Processes Science Resources

Time Periods

1890s-1939:
Atomic Discoveries

1939-1942:
Early
Government Support

1942:
Difficult
Choices

1942-1944:
The Uranium
Path to
the Bomb

1942-1944:
The Plutonium
Path to
the Bomb

1942-1945:
Bringing It All Together

1945:
Dawn of the
Atomic Era

1945-present:
Postscript --
The Nuclear Age


Alpha Racetrack, Y-12 Electromagnetic Plant, Oak RidgeY-12: OPERATION
(Oak Ridge: Clinton, 1943-1944)
Events > The Uranium Path to the Bomb, 1942-1944

During the summer and fall of 1943, the Y-12 Electromagnetic Plant at Oak Ridge began to take shape.  The huge buildings to house the operating equipment were readied as manufacturers began delivering everything from electrical switches to motors, valves, and tanks.  While construction and outfitting proceeded, almost 5,000 operating and maintenance personnel were hired and trained.  Then, between October and mid-December, Y-12 paid the price for being a new technology that had not been put through its paces in a pilot plant.  Vacuum tanks in the first Alpha racetrack leaked and shimmied out of line due to magnetic pressure, welds failed, electrical circuits malfunctioned, and operators made frequent mistakes.  Most seriously, the magnet coils shorted out because of rust and sediment in the cooling oil.  

Alpha calutron operators at their control panels, Y-12, Oak Ridge. An overhead sign nearby reads "Do Not Visit With Cubicle Operators."Leslie Groves arrived on December 15 and shut the racetrack down.  The coils were sent to Allis-Chalmers with hope that they could be cleaned without being dismantled entirely, while measures were taken to prevent recurrence of the shorting problem.  The second Alpha track (Alpha 2, not to be confused with the Alpha II phase of the Y-12 Extension) now bore the weight of the electromagnetic effort.   In spite of precautions aimed at correcting the electrical and oil-related problems that had shut down the first racetrack, Alpha 2 fared little better when it started up in mid-January 1944.  While all tanks operated at least for short periods, performance was sporadic and maintenance could not keep up with electrical failures and defective parts.  Like its predecessor, Alpha 2 was a maintenance nightmare.  

Operator of an Alpha calutron control panel, Y-12, Oak Ridge.Alpha 2 produced about 200 grams of twelve-percent uranium-235 by the end of February, enough to send samples to Los Alamos for experimentation and feed the first Beta unit but not enough to satisfy estimates of weapon requirements.  The first four Alpha tracks did not operate together until April 1944, a full four months late.  While maintenance improved, output was well under previous expectations.  The opening of the Beta building on March 11 led to further disappointment.  Beam resolution was so unsatisfactory that complete redesign was required.  

Ernest Lawrence and others, nonetheless, remained convinced that Y-12 still offered the only realistic avenue to a bomb by 1945.  Despite his concern that the construction could not be Shift change at Y-12, Oak Ridge, August 1945. completed in time, Groves therefore approved in May 1944 the construction of a third Beta building containing two racetracks.   Groves also agreed to a series of complicated changes in the racetracks that would allow their Alpha units to process the material originating from the gaseous diffusion plant, K-25.  This was necessary because K-25 had been experiencing even greater problems during 1943 and 1944 than Y-12.

Previous    Next


Sources and notes for this page.

The text for this page was adapted from, and portions were taken directly from the Office of History and Heritage Resources publication: F. G. Gosling, The Manhattan Project: Making the Atomic Bomb (DOE/MA-0001; Washington: History Division, Department of Energy, January 1999), 23-24.  See also the History Office publication: Richard G. Hewlett and Oscar E. Anderson, Jr., The New World, 1939-1946: Volume I, A History of the United States Atomic Energy Commission (Washington: U.S. Atomic Energy Commission, 1972), 165-167, 294-296.  Click here for more information on the picture of the Alpha racetrack at Y-12.  The two photographs of the calutron operators at their control panels are both courtesy the Lawrence Berkeley National Laboratory.  The photograph of the shift change at Y-12 is reproduced from the photo insert in F. G. Gosling, The Manhattan Project: Making the Atomic Bomb (DOE/MA-0002; Washington: History Division, Department of Energy, October 2001).

Home | History Office | OpenNet | DOE | Privacy and Security Notices
About this Site | How to Navigate this Site | Note on Sources | Site Map | Contact Us