Editing Trinity (nuclear test) (section)

===100-ton test===
[[File:Trinity 100 ton.jpg|thumb|right|0.1 kiloton conventional explosives rehearsal test, Trinity]]
Because there would be only one chance to carry out the test correctly, Bainbridge decided that a rehearsal should be carried out to allow the plans and procedures to be verified, and the instrumentation to be tested and calibrated. Oppenheimer was initially skeptical but gave permission, and he later agreed that it contributed to the success of the Trinity test.{{sfn|Bainbridge|1975|p=41}}

A {{convert|20|ft|m|adj=mid|-high|0}} wooden platform was constructed {{convert|800|yd|-1}} to the southeast of Trinity [[ground zero]]. The high explosive was piled in its wooden shipping boxes in the shape of a pseudo-octagonal prism on it. The charge consisted of {{convert|89.75|ST|t}} tons of [[TNT]] and {{convert|14.91|ST|t}} tons of [[Composition B]] (with the total explosive power of approximately {{convert|108|tonTNT}}), actually a few tons more than the stated "100-tons".<ref>{{cite book |last=Walker |first=Raymond L. |date=1950 |title=100-ton Test: Piezo Gauge Measurements |url=https://babel.hathitrust.org/cgi/pt?id=mdp.39015086443556&seq=3 |publisher=U.S. Atomic Energy Commission, Technical Information Division |page=1}}</ref><ref>{{cite book |last=Loring |first=William S. |date=2019 |title=Birthplace of the Atomic Bomb: A Complete History of the Trinity Test Site |url=https://books.google.com/books?id=h0CIDwAAQBAJ&pg=PT141 |location=Jefferson, North Carolina |publisher=McFarland & Company, Inc., Publishers |page=133 |isbn=978-1-4766-3381-7}}</ref> Kistiakowsky assured Bainbridge that the explosives used were not susceptible to shock. This was proven correct when some boxes fell off the elevator lifting them up to the platform. Flexible tubing was threaded through the pile of boxes of explosives. A radioactive slug from Hanford with {{convert|1000|Ci|TBq|lk=on}} of [[beta ray]] activity and {{convert|400|Ci|TBq}} of [[gamma ray]] activity was dissolved, and Hempelmann poured the solution into the tubing.{{sfn|Bainbridge|1975|pp=41, 58}}{{sfn|Hoddeson|Henriksen|Meade|Westfall|1993|pp=360–362}}{{sfn|Bainbridge|1976|p=11}}

The test was scheduled for May 5 but was postponed for two days to allow for more equipment to be installed. Requests for further postponements had to be refused because they would have affected the schedule for the main test. The detonation time was set for 04:00 [[history of time in the United States#War Time 1918 and 1942|Mountain War Time]] (MWT), on May 7, but there was a 37-minute delay to allow the observation plane,{{sfn|Bainbridge|1976|p=9}} a [[Boeing B-29 Superfortress]] from the [[216th Army Air Forces Base Unit]] flown by Major Clyde "Stan" Shields,{{sfn|Dvorak|2013|pp=9–10}} to get into position.{{sfn|Bainbridge|1976|p=9}}
[[File:Trinity 100ton Test.gif|thumb|left|Men stack crates of high explosives for the 100-ton test]]

The fireball of the conventional explosion was visible from [[Alamogordo Army Air Field]] {{convert|60|mi|-1}} away, but there was little shock at the base camp {{convert|10|miles}} away.{{sfn|Bainbridge|1976|p=9}} Shields thought that the explosion looked "beautiful", but it was hardly felt at {{convert|15000|feet}}.{{sfn|Dvorak|2013|pp=9–10}} [[Herbert L. Anderson]] practiced using a converted [[M4 Sherman]] tank lined with lead to approach the {{convert|5|ft|m|adj=mid|-deep}} and {{convert|30|ft|m|adj=mid|-wide|0}} blast crater and take a soil sample, although the radioactivity was low enough to allow several hours of unprotected exposure. An electrical signal of unknown origin caused the explosion to go off 0.25 seconds early, ruining experiments that required split-second timing. The [[piezoelectric]] gauges developed by Anderson's team correctly indicated an explosion of 108 tons of TNT, but [[Luis Walter Alvarez|Luis Alvarez]] and Waldman's airborne condenser gauges were far less accurate.{{sfn|Hoddeson|Henriksen|Meade|Westfall|1993|pp=360–362}}{{sfn|Bainbridge|1976|p=12}}

In addition to uncovering scientific and technological issues, the rehearsal test revealed practical concerns as well. Over 100 vehicles were used for the rehearsal test, but it was realized more would be required for the main test, and they would need better roads and repair facilities. More radios and more telephone lines were required. Lines needed to be buried to prevent damage by vehicles. A [[Teleprinter|teletype]] was installed to allow better communication with Los Alamos. A town hall was built to allow for large conferences and briefings, and the mess hall had to be upgraded. Because dust thrown up by vehicles interfered with some of the instrumentation, {{convert|20|miles}} of road was sealed.{{sfn|Bainbridge|1976|p=12}}{{sfn|Bainbridge|1975|p=41}}