The 100 Foot Tower

The 100 Foot Tower. . , The 100 Foot Tower , Kenneth T. Bainbridge, Director of the Trinity Project, contracted with the Blaw-Knox Company of Pittsburgh, Pennsylvania to manufacture the steel tower to Bainbridge's specifications. It was then shipped in sections to New Mexico where Ted Brown's Construction Company of Albuquerque assembled it. , Gadget , The nuclear device detonated at Trinity, nicknamed "Gadget,” was shaped like a large steel globe. Like the Fat Man bomb dropped on Nagasaki, it was a plutonium implosion device. Plutonium implosion devices are more efficient and powerful than gun-type uranium bombs like the Little Boy bomb detonated over Hiroshima. Plutonium implosion devices use conventional explosives around a central plutonium mass to quickly squeeze and consolidate the plutonium, increasing the pressure and density of the substance. An increased density allows the plutonium to reach its critical mass, firing neutrons and allowing the fission chain reaction to proceed. To detonate the device, the explosives were ignited, releasing a shock wave that compressed the inner plutonium and led to its explosion. , Caption: , Norris Bradbury, group leader for bomb assembly, stands next to the assembled Gadget atop the 100 foot test tower. Later, he became the director of Los Alamos, after the departure of J. Robert Oppenheimer. , Text of a letter describing the tower's specifications: , To: Mr. D. P. Mitchell , From: K. T. Bainbridge , Subject: Purchase Request No. 8889 for bottom 100 feet of 200-ft. Blaw-Knox Tower, Drawing 722626. Prior Reference AR404, The special requirements for the 100-ft. Blaw-Knox tower are: , 1. The height of the tower shall be approximately 100 ft. to the working platform. This should be the bottom 100 ft. of the 200-ft. tower as given on drawing No. P22626 (Blaw-Knox), plus pyramid or equivalent, i.e., next 12-ft. section, at least 10 ft. higher in order that sheaves can be mounted at the pinnacle for raising 5 tons of equipment centrally, less than 5-1/2 ft. diameter for largest piece, above the 100-ft. level. , 2. Platform or floor at approximately 100-ft. height, minimum 15 ft. square with removable section in center to provide 6 ft. diameter clearance through which to hoist equipment; removable section must be capable of supporting 5 tons dead load at central point when in place. , , 3. Pressed steel stairway with railing and platforms every 25 ft. of height or oftener. , 4. The platform at approximately 100 ft. height must have adequate railing for safety and at least 8 ft. head room over most of the floor area. Platform flooring can be wood. Loading around peripheral section will not exceed 6 men and one 300-lb. piece of equipment 3 ft. in diameter. , , 5. Paint finish will be entirely satisfactory; galvanized finish not required. , , 6. Delivery to Project T siding desired by June 4; absolute latest date, June 15. , , 7. Want specification of footings for compacted sandy soil on or before April 15. (This will allow procurement of steel for footings in April and pouring by local men or by contract starting May 15.) , , 8. Can Blaw-Knox furnish field crew to erect tower, or should we approach the Signal Corps for a trained crew? This is essentially an SCR-271. , , 9. What special equipment is needed for the erection of the tower. Can this be supplied by the field crew? ,