committees. though the tests were committed to success, the castle bravo explosion was two times more powerful than expected, and resulted in radiation contamination of nearby islands, sickening soldiers and islands. the army department declassified the film in the early 1990's. ♪ >> operation castle, the fifth in the series of tests on the pacific proving grounds. another of the relation of men, of machines, another meeting of airships and troops. here was the best of physics, of

metallurgy, of electronics. during the months after the historic definition, preparations for a new series of tests to solve the problems of a deliverable megaton weapon went ahead at an accelerated pace throughout the country. operation castle became a reality and is now successfully concluded. the report which follows is a summation of what occurred at the pacific proving grounds during that operation in 1954. here the league office record is general clarkson, task force commander. >> operation castle was concluded on the 14th of may in 1954. castle was an all thermonuclear test, a test of devices in the megaton range. we feel that the report of this important test should give the failures as well as the successes, should reflect the changes in thinking that occurred during the test.

we hope this treatment will help you understand the problems that we experienced during the operation. ,his program encompassed them three shots on land and 4 shots -- our main base camp on the keeney was located in the same island ini was located on the same island complex. islands functioned as the center of land-based operation. this then was the weapons schedule and the operation plan for castle on march 1. , the third time this island has been used as the headquarters for a pacific task force. for this operation, our weapons assembly area was conducted at

the southern tip of this valuable piece of real estate. the first time on any operation that weapons were assembled and then moved out to the firing site. bepon development would impossible without diagnostic instrumentation. such instrumentation is expensive, very expensive as this distance from home. for this reason extensive instrument vision was limited to a few shots, and each diagnostic experience was carefully considered before being concluded in the program. instrumentation, while more elaborate than that of other shots, is representative of the top of diagnostic studies made. oforders to rig the yield the neutron bomb from its rate to assistication, and in the determination of total yield. high-speed cameras and photo towers to indicate total yield

of the device. scopes recording electromagnetic radiation and cameras thought to obtain the time between primary and secondary bomb technicians. other cameras to look directly into the open door. a great mass of information was gathered as a result of an array of 12 evacuated pipes. these pipes are like peepholes looking at portions of the weapons case to pick up gamma and neutron emissions from many stages of the reaction. starting at h-48 hours every person at bikini atoll was scattered from the islands and moved aboard task force ships. the only meant to remain with the members of the firing party, protected in their bunker on ene island. since the first time in operation crosslegged, bikini took its place in a time of

historic testing. the date was march 1, 1954. this photograph was taken from an airplane at 50 miles. the width of the fireball at this time, about three seconds after detonation, was four miles. the frame size of the picture is six by eight miles. the top of the fireball at this time, 40 seconds after detonation, was five miles above sea level.

to prove that we can have a high yield weapon waiting less than 10 tons. the tremendous yield resulted in a serious fallout situation at the keeney and sent other atolls downwind from ground zero. this was the forecast wind direction. the actual wind was in this direction, some 10 degrees less favorable than forecast. even so the winds were in the area of acceptable fallout. however the unexpected high yield caused significant for to occur 110 miles distance. .50 from bikini after the navy's were evacuated,

radiation survey teams were brought back to the exposed atoll, where studies were made and water and soil samples taken. 82.pulation of evacuation was carried out on the second morning after the shot. drake had no native population, but was occupied by 28 men of the task force. eight men were evacuated by air at h+28 hours. 150 natives were also evacuated, although radiation levels here were relatively light. the removal of personal from the contaminated pay tolls -- contaminated atolls was done mainly by destroyer. were primarilys for security purposes, but were easily adapted for use as

evacuation vessels. all of those exposed were taken where complete physical examinations were carried out. every effort was made to ensure their comfort and well-being. follow on bikini temporary rendered that atoll unusable. on the side of our control 35 hour was recorded. hundreds of rankings per hour were measured on bikini islands. even if radiation had not been a factor, blast damage was considerable. it would have taken a sizable effort to make the island again usable in the base camp. the ground shot and full of experienced by our firing party forced us to give up the idea of

a manned station. the necessary electronic systems to permit firingn by radio. the possibility of further damage to previously prepared shot sites at bikini caused us to change our schedule at this point. back in the states at about the same time castle was in operation, the results of these drops plus tested using an firing systems made it possible to have a deliverable weapon ready, approximately 19 feet in length and five feet in diameter. while the case is made of aluminum, this is by no means a light weapon, since it ways 43,000 pounds. -- weighs 40,000 pounds. it was pork board its firing barge. -- aboard its firing barge. it was thought firing could be done from a barge on open water,

resulting in an appreciable reduction in full at and considerable simplification of operational problems. it proved a difficult shot to get off. we had to proposed -- had to postponse 14 days because of weather. winds blowing to the south, then to the west. this took 10 days. then for 16 days the winds remained in this sector. this island might receive fallout if the winds were to close to borderline conditions. at 7:00 a.m. on the 26th of march, the forecast was for a favorable wind in the right direction. 6:30 thewas set for next morning, 27th of march. on this rather unimpressive barge floating in the bikini lagoon rested a device that carried the hopes for a large

step forward in the weapons development program. the distance of the camera aircraft is 50 miles. the frame size of the picture is 14 by 18 miles. the film is running at normal speed. 200 miles away. daily commuting from ship to shore cost several working hours each day. we had to watch the radiation

doses received by the people working on the test. man was set 3.9 for for the operation, and with the men had tos work fast. , the armedous tests forces took advantage of the castle series and broadened their knowledge of the effects produced by high-yield weapons. as an example, there has been much uncertainty in specifying the minimum safe instance for aircraft delivery -- delivering weapons. blessed and thermal effects were aircraft,n b36 positioned so that some damage was expected. this data will help us to specify the yield at which parachute drops are required for delaying a definition, as well as providing us with answers to many questions that arise when positioning for multiple drops

is considered. the whole picture of fallout contamination becomes of increasing importance with high-yield weapons. ships wereram, drone sent into fallout areas to evaluate the work of a system for ship decontamination. we found we could measure fallout even in large ocean areas by making aerial surveys using extremely sensitive radiation protective equipment, and with service crafts such as tugs and destroyers. we were able to document for the first time follow data from high-yield detonations. it is now known that fallout from the larger castle shots blanketed areas of more than 5000 square miles with radioactive material that would have been legal to unprotected personal. -- lethal to unprotected personal. this is a new insight to the method of using high-yield weapons in strategic and

tactical situations. it is now around the 10th of april, and the recap of our story of castle. three shots down, and three to go. the weather worked against keeping a firm firing schedule. during the middle two weeks of april, we were faced with the same situation. winds above 10,000 feet were again in an unsafe direction. under these conditions, populated areas were directly in the line of fallout. again we postponed, awaiting a favorable forecast. this occurred on the 25th of april at noon. angered and its location -- incurred in its location, zero our approach. the time of firing, 6:10 on the 26th of april. camera position, 50 miles at 10,000 feet.

size of picture, 14 by 18 miles, photographed at normal speed. the yield was seven megatons. the weapon was scheduled for firing on the fifth of may. this was 10 days since the last shot. for the first time in the operation, we had what the concerted tittered -- what could

be considered a normal integral of shots. a command be 36 -- camera position, 50 miles at 10,000 feet. size of picture, 14 by 18 miles, photographed at half normal speed.

the six and final shot of operation castle. this device was also flown out to the forward area for final example -- final assemble. its zero was towed to point. over the spot that is now a crater, anchored in position. smallestn may 14, the device in operation was ready. this test initiated an

investigation of small lightweight thermonuclear weapons of a megaton class. is 14 by 18ure miles. the yield was about 1.7 megatons, essentially as predicted. from this firing we learned that we had the capability of developing megaton weapons weighing less than 10,000 pounds.

castle was by far the most complex and significant operation in the short but impressive history of nuclear testing, and in my opinion, absolutely vital to national security and the security of the free world. ♪ we were percent by operational -- beset by operational problems of the magnitude not encountered previously.

the degree of flexibility obtained by the task force as a whole in meeting these problems is only one example of the spirit of cooperation evidenced by all members of the free services and by the members of the atomic commission. to the men who made operation castle a success, to the same men who were asked to undergo many personal hardships, i have already expressed my gratitude. i am sure that these men also deserve the sincere appreciation of the department of defense, the atomic energy commission, and the people of the united states. this concludes the report on operation castle. ♪ >> up next, we continue our

look at the 1954 operation castle nuclear test. military affect studies on nuclear castle is a 40 minute report detailing the aftermath of six powerful nuclear tests in the marshall islands, showing the effects of radiation on civilians and american military personnel, outlines nuclear weapons advances and considers the effects of atomic bombs and follow-up -- and fallout on american cities. the equivalent of 1000 hiroshima bombs. 23 japanese fishermen were also contaminated, which stained u.s.-japan relations. ♪