The Manhattan Project: Making the Atomic Bomb

Part IV: The Manhattan Engineer District in Operation

Shakedown at Y-12

During summer and fall 1943 the first electromagnetic plant began to take shape. The huge building to house the operating equipment was 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.

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 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, the second Alpha 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.

Alpha 2 produced about 200 grams of twelve percent uranium-235 by the end of February, enough to send samples to Los Alamos 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, 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. To make matters worse, word spread that the K-25 gaseous diffusion process was in deep trouble because of its ongoing barrier crisis. K-25 had been counted upon to provide uranium enriched enough to serve as feed material for Beta. Now it would be producing such slight enrichment that the Alpha tracks would have to process K-25's material, requiring extensive redesign and retooling of tanks, doors, and liners, particularly in units that would be wired to run as hot, rather than as cold, electrical sources. 34