 history now. Past history for the record books and live history for future planning. It was a double-headed test like Buster Jangle and Tumblr Snapper, covering both weapon development and civil and military effects. And in some ways it was our biggest research job so far. The preparation job was big too. Many hundreds of tons of material and months of intense planning and labor by skill personnel were the ingredients poured into a gigantic test tube on Nevada proving grounds. In the spring of 1953 the mixture boiled up in a series of 11 atomic detonations. Operation upshot knothole. The residue or end product of the reaction was knowledge. Some of it in a yes or no form immediately useful and some of it requiring detailed analysis. The funnel into our Nevada test tube was the same old road up from Las Vegas. Nearly 80 miles of standard desert road which carries very little traffic when the proving grounds are quiet. Indian Springs was still primarily an Air Force support station for atomic test operations. The desert rock troop encampment was in the same old place off to the left after we turned off highway 95. Inside the check gate and mercury were living in technical areas and the field headquarters of the main test organization. A joint AEC and Department of Defense activity. From mercury the road goes roughly northward. It cuts through one range of hills. On across the valley a Frenchman flat then heads up into a notch in a second range. In this notch is the CP the control point the real nerve center and communications hub of the test site. This was the test manager's forward headquarters for the series and primarily the center of operations for the weapons development program upshot. Looking out from the control point an observer can see both of the major blast areas. Frenchman flat a dry lake bed is still visible back in the valley we just crossed. Though the actual ground zero point can't be seen. Yucca flat lies on northward in the next valley beyond the control point nine of upshot not holds 11 shots were fired out here on Yucca between March 17th and June 4th. These nine seven tower shots and two air drops were the AEC's weapon development tests. While such tests are not the main point of this film their trend the goals they're aimed at are ultimately of great importance to the military services. So since these tests are primarily the concern of Los Alamos scientific laboratories we turn to Los Alamos for an outline of the concepts and the objectives involved. As usual we're up to our next unraveling what happened in the last test and getting ready for the next ones. Now this weapon development business we've been getting together some material for brief orientation talks. I want to emphasize that the amount of discussion given each shot is no indication of its actual importance. In fact I may have to say at least about some of the most important shots. Shot number two had for its source of energy a boosted fission device. It was part of a development that we think will eventually give us a weapon of approximately 30 inches in diameter. Three to four thousand pounds weight and a yield in the neighborhood of five hundred kilotons. Around 35 times that of the Hiroshima bomb. The next development shots were three and five. Shot number four it was the first air drop on upshot and was detonated at approximately six thousand feet. The highest burst of any gadget we've ever fired. So once over lightly at least that winds up the story of operation upshot and out holes weapon development program. But outside of any discussion outside of the laboratories out on the Nevada proving ground itself there was a great deal more to consider than the basic ideas back of the upshot firings. There was the same old job complex and vitally necessary of diagnosing the actual performance of gadgets being tested. Gadgets designed by Los Alamos and by Project Whitney of the University of California Radiation Laboratory. It's an old story in a sense to those of us in the services who have watched and assisted the preparation of previous tests. But that doesn't alter its prime value to get the inside dope on the behavior of any experimental fission device. The scientists always want at least the answer to one classical three-headed question. What was the alpha rate? The transit time and the yield. And yield alone is computed and cross-checked in many ways. Probably most accurately by radiochemical analysis of cloud material collected by the sampling planes. And by ultra high speed photography of fireball growth. Another Nevada activity of the AC was its civil effects program of tests originated by various non-military federal agencies. For example two typical frame houses were exposed to the first blast of the series for the federal civil defense administration. Some 50 civilian automobiles were included in this test. Several types of family and community bomb shelters were also tried out. The blast from the 16 kiloton shot hits the house at 3,500 feet. Around three quarters of a mile. Almost total destruction. The other house at a mile and a half showed only moderately heavy damage. These visually spectacular tests were only one portion of a big program which included extensive dosimeter and radiation research and important biomedical and genetic studies by some of the country's top scientists. The second major phase of the 1953 series military effects test was from the service point of view the main feature of the show. All early planning and coordination of these tests was handled by the director of weapons effects tests set up for this purpose by field command armed forces special weapons project. In the operational phase personnel of this directorate were integrated into the main test organization. There they continued to be responsible for all military tests and for the important military support given to the AEC's programs. Such support for example as the air weather service forecast on which are based the fire or no fire decisions for each shot. The bulk of the huge not whole program was carried out on Frenchman flat. Though some military tests were run on the weapon development shots up on Yorker. Number nine on 8 May was the first not whole shot. An airdrop of a 26 kilo tough weapon. All military tests on Frenchman flat were originally built around this shot. The relatively high burst height 2400 feet was a compromise to fit many tests rather than to inflict maximum central damage. Shot 10 25 May proof tested another delivery system the army's 280 millimeter gun. When this shot was added to the program some additional effects tests were scheduled to observe results of the low burst height approximately 520 feet above ground. Since no gun type assembly had been detonated since the Hiroshima bomb the weapons development scientists had on this shot their first opportunity to study the nucleonic behavior and fireball configuration of such a device. 15 kilotons. Unlike the situation with an implosion weapon the scientists were here able to observe fireball growth from a body of fishable material whose exact shape and dimensions at the moment of detonation were known. As scheduled the military effects test total well over 70 distinct projects under nine major program headings. Headings which might in a sense be considered as signposts guiding us along our road. The road full of questions that we followed through not whole one of the biggest military test programs in our records. To begin with we wanted more and clearer data unblast and precursor phenomena and on the mark stem and the triple points path. We wanted enough data to predict what these factors plus thermal and nuclear radiation will do of military significance to any living being or object they can reach. These were the objectives of our road. We haven't the time to stop for a look at every signpost along the way. We'll just have to hit some of the high spots and new spots. A project for instance that didn't use a new technique but that hadn't been covered in previous report films had for its aim to measure free field blast pressures in regions of concern to delivery aircraft and to determine the triple point height in at least one location. Two B-29s did the muscle work on the job. Just before shot nine they dropped 14 canisters in the target area. Time to be hanging on their parachutes at burst time and a long line some 5,000 feet high and spaced out to nearly seven miles from the burst point. Each canister telemated its altitude and surrounding air pressure to a ground station tape recorder. The tape also marked time of burst and time of shock arrival at the canister. The close-in canisters each received two kicks. One from the incident wave and one from the reflected wave. Further out each canister received a single cake from the mark stand indicating that the triple point where the two waves merge had sliced up through the canister line at a distance and altitude that we could compute from the recording tapes. In the nuclear radiation program particular interest centered on shot 10s neutron flux measurements. The first ever made on the detonation of a gun type assembly. Gold, tantalum and sulfur threshold samples were used to detect neutron energy levels from thermal to around 10 million electron volts. The total flux per kiloton was the highest ever observed running 10 to 30 times as high as the implosion shots 8 and 9 and extending the median lethal radiation range some 600 feet. One novel feature of upshot not whole was the first use of drone aircraft on a continental atomic test. Navy AD tools were instrumented for blast and thermal radiation response and were flown at near critical distances from several bursts. Results indicated that comparatively moderate thermal inputs may seriously reduce the blast resistance of some aircraft components. Standard blue aircraft paint proved clearly inferior to white or unpainted metal surfaces for protection against destructive thermal effects. Similar flights by manned and the instrumented Air Force B 50s and a B 36 gave structural response data needed to establish minimum safe operational parameters for high performance bombers. Other bombers from the strategic air command flew in with the drop plane testing techniques for obtaining yield height of burst and ground zero location. The three essential parameters of IBDA indirect bomb damage assessment on the biomedical program Air Force QF 80 drones instrumented to measure gamma radiation and with test animals aboard were flown through atomic clouds at 30,000 and 32,000 feet. They were each controlled by primary and secondary mother ships and manned fighter escort stood by to shoot down any drone that malfunctioned. These tests indicated that personnel of pressurized aircraft passing at 400 knots through a cloud at least four minutes old from a weapon of less than 30 kt would receive an external dosage of less than 50 rentals with a negligible respiratory hazard. On the thermal effects program one project concerned parked aircraft and aircraft components an extension of previous tests. New data were obtained on structural weakening from thermal inputs to low to cause visible damage. Ploth thermal shields were proved to have considerable value in reducing damage to parked aircraft. Some aircraft fabrics were destroyed at levels as low as two calories per square centimeter while magnesium sheet and foil covered panels were undamaged by 20 calories. It was also found that strong tie-downs may protect aircraft parked nose-on to the blast from much of the damage that will occur if the plane is unmoored and free to lift and roll. But for side-on or tail-on orientations the tie-downs may actually increase damage. Another important section of the thermal program was a study dealing with normal city vulnerability to fire started by atomic weapons. Three cubicle houses 7,700 feet from zero were erected for one phase of this study concerned with exterior kindling fuels. The first house has a clean safe yard but dry rot is working and the unpainted siding no rot here but toys weeds and trash against the fence a clean yard painted fence and maintained siding number nine goes off 13 calories per square centimeter over pressure three and a half pounds per square inch time sequence photography shows the results the structure on the right from the yard trash which set fire to the fence on the left rotted wood in the siding was the ignition point sound painted wood and a clean yard allow the center house to survive the fire hazards in these projects are not unusual either six big American cities were inspected to ensure that representative conditions were tested conditions which suggests that a bomb of even this nominal power could start more than a hundred thousand fires over 25 square miles of urban area. Our next thermal project run on shot 10 required a new instrument line east from ground zero roughly opposite the main blast line equipped with thermal recording devices and with blast gauges at zero and 10-foot heights. The first phase designed to find out how much protection white smoke would give against thermal flash employed a standard oil fog over a portion of the new line in theory this smoke would scatter and reflect fireball heat this was a small-scale experiment but evaluations have indicated that attenuation of radiant energy approach 99% to explain the second phase of the project employing black smoke we must go back to tumbly snapper on the low altitude burst of tumbly four high-speed cameras recorded a phenomenon never noticed before a shark wave preceding the main shark front here it is again this precursor wave as it was called registers on blast line instruments with a pressure time graph of this type showing a considerable climb and duration before arrival of the main shark front a normal shark wave with no precursor is quite different hitting the instruments with an instantaneous pressure jump the mechanics of precursor development appear to be these a weapon bursts and thermal radiation creates an intensely hot ground layer of air a layer filled with dust from what is called the popcorning of the hot ground milliseconds after the thermal flash the incident shark wave reaches the ground and expands trailed outward by the usual reflected wave then a new wave the precursor begins to build out from the base of the incident wave racing ahead through the heated air layer an intense dust cloud follows closely rising initially to about 50 feet and later to several hundred feet one important effect of the precursor is to lower peak static pressures without a corresponding reduction of dynamic or wind pressures the precursor builds steadily in height but does not seem to inhibit formation of a mock stamp though exact dimensional relationships are uncertain eventually running into cooler regions the precursor slows and is overtaken by the mock stamp from that point on the blast wave structure is normal again it should be emphasized that a precursor can form only if the ground air layer is sufficiently hot so if height of burst is increased yield must be increased without the yield increase the ground air will be too cool for precursor formation as was the case on shot nine our first effect shot 26 kt at 2400 feet shot 10 15 kt in only 500 feet developed a strong precursor it was on this shot that we ran the smoke experiment a carbon black smoke was established over nearly a mile of the new instrument line we expected that the top of the black smoke would absorb thermal energy and produce an extra hot layer well above ground possibly generating a controlled super precursor at that height or in some other manner reducing blast effects on ground targets the experiment was handicapped to an unknown degree by wind billowing the smoke up to 300 or 400 feet modifying the planned geometry as it happened the ground level precursor which developed under the smoke was stronger than the one in the clear although it extended only half as far before decaying to a conventional blast form this test was not conclusive as to the effects of a heat absorbing black smoke on blast a further precursor study was set up to determine whether ground surface heating from thermal flash could generate a shock wave before arrival of the normal shock front panels 10 feet square faced with variously heat absorptive and reactive materials were tilted for maximum exposure to the thermal radiation of the two effect shots post shot study of the gauge records showed no clear evidence of thermally induced shock waves we come now to the biggest program the primary reason for shot 9 the first effect shot the biggest program in sheer volume in theoretical predictions confirmed or refuted and in the mass of empirical knowledge gained 28 separate projects came under this heading beginning with basic measurements on simple cylinders and rectangular concrete slab structures in a number of orientations these passive targets heavily instrumented were not designed for response by displacement but only to record shielding and loading factors at various heights and aspects the findings of this important job can now be extrapolated for prediction of blast loading on a great variety of targets without direct testing we begin to bump into the precursor again a trust bridge section 2300 feet from zero shot 926 KT 2400 feet high produced a small permanent set in the top cord with an overpressure of 11 and a half pounds per square inch but the mark stem had not formed to reach the height of the bridge eight and a half pounds did this on shot 10 500 feet high 15 kiloton yield with a precursor blast wave and a mark stem already higher than the bridge apparently for wind or drag sensitive targets of this type a low burst is more damaging than a high burst at similar peak pressures a test of army prefab daily bridges shot 9 4100 feet from zero essentially undamaged the bridge slid back on its peers as expected moving 43 inches from a peak pressure of 8 pounds 9 pounds from shot 10 hits another bridge movement out of all proportion to that cause by almost the same static pressure on the first shot army equipment which included 54 trucks in jeeps was exposed to shot 9 pressures ranging up to 21 pounds to the inch thermal input reached 130 calories per square centimeter damage was generally moderate as expected all but two vehicles one with burn tires and one with a missile punctured radiator could be driven away under their own power for shot 10 army tanks artillery and 22 trucks were exposed to pressures expected to range from 3 to 55 psi once more damage was much greater than expected equipment was not merely overturned but often torn to pieces or hurled great distances at overpressures from which no such effects were predicted pressures which had done negligible damage to identical items on shot 9 obviously shot 10 was handing out surprise data it was evident that our old static pressure criteria were not valid for predicting damage to wind sensitive targets in the precursor region of low burst not only were their violent high frequency pressure fluctuations in this region but the precursor depressed static pressures no longer had the same relation to dynamic or blast wind pressures found in a normal shock wave standard command posts foxholes and machine gun positions were located on shot 9 at 600 800 and 4000 feet from zero over pressures 8 to 22 pounds to the inch general analysis indicated that cover supporting timbers began to fail at 8 psi while revetment stood up to around 20 pounds conventional sandbags tended to catch fire and spill their contacts one interesting finding was that foxhole covers can greatly reduce inside pressures which may otherwise build to twice the outside pressure field hospital installations were displayed for shot 9 at ranges around 4400 9000 and 15000 feet in both above ground and dug in positions at each location radiology sections operating rooms pharmacy tents all complete and ready for use 38 calories per square centimeter 8 pounds per square inch operationally a complete ruin although a few items of equipment were salvageable missile hazard was unquestionably heavy the 15000 foot installation around one and one quarter pounds pressure damage limited to collapse of the above ground tents a significant finding of these tests was that considerable protection to personnel and equipment would be afforded by revetting field medical installations 6 marine LVT's landing vehicles tracked at distances from 800 to 4500 feet from zero with pressures reaching 22 psi 2400 feet over pressure 11 pounds damage was light on all vehicles on shot 10 the same vehicles buried from 1000 to 3450 feet from zero pressures running up to 47 pounds shot 10 damage was again unexpectedly heavy as compared with shot 9 with one vehicle destroyed and three severely damaged in the precursor region which on this shot extends out to around a half mile from ground zero these tests suggest that normal shock waves from high bursts will damage LVT's only moderately up to 22 psi while low burst will do severe damage above 12 and a half pounds curtain wall panels on a series of concrete test cells some with window openings some without the panels were constructed of various masonry materials such as brick cinder block clay tile and combinations of these materials similar variety went into roofs and interior partitions on shot 9 4 and a half pounds over pressure does this 6700 feet from zero 7 pounds here 4400 feet rain unreinforced bricks did up fairly well though cinder block and trance I chatted walls with 20% window opening showed much greater blast resistance than blank walls though damage to interior partitions was high three frame structures with windows and skylights containing various types of glass and plastic blazings were set up at 7600 12500 and 20,000 feet from shot 9 pressures were 4 psi or lower a few conclusions that can be drawn now or that quarter inch clear plastic shattered least of the material tested quarter inch wire mesh was the largest mesh effective in reducing interior missile has it exterior jealousies were worthless and explosion hardware has very limited usefulness and may even be disadvantageous signal core place radial and transverse pole lines underground wires and aluminum towers at different distances to test damage effects and determined time required to restore communication facilities on shot 9 pressures of 7 to 9 psi knocked down the transverse pole lines at 3500 and 4500 feet and partially destroyed lines at 5500 feet in the 5 pound region however radial pole lines and down to the blast were almost undamaged similarly towers at 3400 and 4400 feet were knocked down and the one at 5400 feet heavily damaged at 6400 feet the top section of this 240 foot tower was made unsafe by four and a half psi shot 10 damage to these installations was much heavier the blast winds destroyed even the radial pole line to 2500 feet with static pressures by which it was undamaged on shot 9 air force marine and quartermaster pol installations were given extensive testing the major items were 5 and 55 gallon drum stacks bulk storage tanks and various subsidiary items such as can cleaning metering filtering and pumping equipment in general shot 9 damage was light or insignificant there were minor gasoline fires drum and can stacks were scattered slightly in the maximum pressure areas around 16 psi two collapsible 900 gallon tanks were ruptured by 11 pounds at 2600 feet on shot 10 results were unexpectedly violent all stacks disintegrated with cans and drums thrown hundreds of feet and left flattened or badly crushed all marine fuel handling equipment was destroyed except one collapsible tank almost complete destruction occurred at better than 2000 feet at the same pressures that did trivial damage on shot 9 a study of tactical importance 145 ponderosa pines set in concrete approximately 6400 feet from shot 9s zero instrumentation was thorough a few major types being pressure gauges at three heights time recording animometers pitot type dynamic pressure detectors and snubber wire arrangements to measure deflections pendulums were substituted for the lollipops of former operations to provide mechanical simulation of tree response as on many of these projects camera stations were set up to provide high speed motion picture coverage of blast effects thermal input 18 calories per square centimeter resulting in only mild char on tree trunks since the normal ground litter that will ignite at around 3 calories was lacking static pressures around 4 psi post blast survey indicated that approximately 20 percent of the trees were broken and the missile hazard from falling trunks and limbs would be substantial there was scant reduction of static pressure inside the stand but at 20 to 40 percent reduction of dynamic or drag pressures thermal shielding proved excellent with negligible penetration beyond the fourth row of trees 16 items of army rolling stock were exposed on shot 10 only a 45 ton diesel locomotive one riveted and one welded steel tank car 13 box cars loaded and unloaded of various types 6600 feet 2 pounds over pressure 4400 feet 4 psi one empty box car turned over one loaded car damaged 3400 feet 6 psi box cars damaged or overturned 2800 feet 7.5 pounds 1850 feet 9 pounds 1500 feet before being hit by 13 pounds to the inch and here's the same view afterward the frame of one of those tank cars was thrown against a building 200 feet away a tank car body went 1200 feet the wise and how's of these excessive damage effects at static pressure levels where no such results were anticipated will require further study as will the mechanics of precursor development over surfaces less suited to the development of heated ground air than the Nevada desert while to date these damage effects have been observed in the precursor it does not follow that attack conditions should be chosen to maximize precursor formation such effects may be characteristic of any low burst without regard to precursor phenomena although high burst are still required for optimum damage on many important targets the tremendous destructive force of a low burst has brought about an interim restatement of damage criteria for drag sensitive targets and was the most important single finding of the military effects tests of operation upshot not whole