US Archive Page - 1 | 2 | 3 | 4 | Program History | Operation History | Testing Database | Image Gallery | Lacrosse - |Redwing| Date: 18:20 04/05/1956 | Type: Surface @5m | Yield: 40 Kt A test of an externally initiated boosted primary in a thermonuclear system mockup for the TX-39 (a redesign of the Mk-15). The device was 87cm wide and 254cm long, weight was 3804 kg. This primary was used in the Redwing Apache thermonuclear shot, and was similar to the device later fired in Plumbbob Priscilla. The crater was 122m wide and 16.7m deep. Blast effects studies were conducted on vehicles during Lacrosse. 10 jeeps were placed facing into and broadside to the detonation at distances ranging from 700 to 1.3km. Shockwave precursor movement over vegetated earth surface versus sandy surfaces was also examined. The cloud reached an altitude of 10.6km, low for similar shots. Bulldozers cleaned some of the islands following the shot by scrapping away contaminated soil and debris. Cherokee - |Redwing| Date: 17:50 UTC 20/05/1956 | Type: Airburst @1325m | Yield: 3.8 Mt The first US air drop of a thermonuclear weapon. It was intended to gather effects data for high yield air bursts, but also was a political demonstration of the United States capability to deliver H-bombs by air. The intended ground zero Namu Island, but mistakenly dropped a different island. The bomb detonated 6.4km off target over the ocean northeast of Namu. As a result essentially all of the effects data was lost. Although the Mk-15/39 was a radiation implosion design that harnessed thermonuclear reactions, it was a transitional design that could also be considered a radiation implosion boosted fission. The secondary used an HEU jacket that would have produced a high fission yield even without the fusion fuel it contained. The bomb was 89cm wide, 345cm long, and weighed 3114kg. The cloud rose to 2,651m. View 2 | View 3 | View 4 Zuni - |Redwing| Date: 17:56 UTC 27/05/1956 | Type: Surface @3m Yield: 3.5 Mt The Bassoon device fired in Zuni was the first test ever of an innovative three stage thermonuclear design. A test of a 'clean' (low fallout) device using a lead tamper around the thermonuclear third stage. Only 15% of the yield was from fission. A 'dirty' version was later fired in Redwing Tewa. Crater dimensions were 710m wide and 35m deep. This design was later developed into the Mk-41 bomb, the highest yield (25 Mt) weapon ever deployed by the U.S. View 2 | View 3 | View 4 | View 5 | View 6 Yuma - |Redwing| Date:BT ticket says - 19:56 27/05/1956 | Type: Surface @60m | Yield: 0.19 Kt A linear implosion design intended for air defense warheads. The device, known as Swift, was a boosted asymmetrical design. The device failed to boost and the yield was far below predictions. The Swift was only 13cm in diameter and weighed 44kg. This was the smallest diameter, and lightest nuclear device tested up to this time. It used Octol 76/24 as the explosive and was presumably a plutonium fueled device. Erie - |Redwing| Date: 18:15 UTC 27/05/1956 | Type: Tower @63m | Yield: 14.9 Kt This was a test of the boosted primary and the implosion system for the TX-28C ("C" for "clean") thermonuclear bomb. The complete device was 51 cm in diameter, 140 cm long, and weighed 955 kg. The primary weighed 65 kg. Seminole - |Redwing| Date: 00:55 UTC 06/06/1956 | Type: Surface @2m Yield: 13.7 Kt An unusual test, a combined weapons development/effects test device exploded in a tank of water to couple the shock wave to the ground. Mounted in a circular chamber inside the water tank which was accessible by a corridor. The chamber was 3m off center from the tank center, leading to an asymmetry in the crater. The crater was 201m wide and 8m deep. The shot was designed so that by the time the fireball reached the wall of the tank, it had transitioned from thermal radiation-driven growth to hydrodynamic growth. The test device was a TX-28 primary/implosion system. The device was 50cm in diameter and 140cm long. The device weight was 830kg, the primary itself weighed 65kg. Flathead - |Redwing| Date: 18:26 UTC 11/06/1956 | Type: Barge @4.5m | Yield: 365 Kt This was a LASL test of the TX-28S (S for 'salted'), a dirty high fallout bomb design. This boosted device was the first nuclear test ever to use a PBX (plastic bonded explosive) for the implosion system. The yield was 73% fission. The device weighed 634kg. Flathead was detonated on the same test location as shot Dakota. Osage - |Redwing| Date: 01:13 UTC 16/06/1956 | Type: Airdrop @210m | Yield: 1.6 Kt Proof test of the XW-25 warhead. A light weight, low yield, plutonium warhead intended for air defense and other tactical applications. This spherical implosion device had a diameter of 44cm, was 65cm long and weighed 79kg. It was dropped in an instrumented Mk-7 drop case, which had a total weight of 1,429 kg. Dakota - |Redwing| Date: 18:06 UTC 25/06/1956 | Type: Barge | Yield:1.1 Mt TX-28C variant prototype test. The W-28 small diameter, light weight ('Class-D') thermonuclear weapon design became the most versatile and widely used design ever adopted by the United States. Entering service in 1958, the W-28 remained in service until 1990. It was fielded in 5 models, with 20 variants. The test device was 50cm in diameter, 147cm long, and weighed 815kg. This test did substantially better than expected. Dakota was fired over the Flathead test site. View 2 Mohawk - |Redwing| Date: 18:06 02/07/1956 | Type: Tower @90m | Yield: 360 Kt A boosted swan primary and a flute secondary, it was fired from a 90m tower on Eleleron Island. The crater was 2.4m deep and 408m wide. The crater was unusually wide and shallow mostly due to pressure collapse of the porous coral soil. The cloud reached an altitude of 19.8km. The shot heavily contaminated the island and strong radiation was detected on the north end of the atoll, strong enough to fog the photographs taken by aircraft of the area. Recovery operations were delayed for several days as a result of the high radiation levels. One gamma ray diagnostic experiment utilized a massive shield near shot the tower. The shield consisted of 15cm of lead, and 30cm of paraffin on the device side to hold back neutrons. Paraffin being a neutron absorbing material due of its high hydrogen content. This shield caused a pimple to form on the fireball. Apache - |Redwing| Date: 18:06 UTC 08/07/1956 | Type: Barge Yield: 1.85 Mt A test of a two-stage device using a 'Zither' secondary stage. A prototype for the Mk-27 warhead intended for the Regulus I missile. A LASL primary design was used, tested earlier in Lacrosse. A high percentage of the yield was due to fission. Apache was a barge shot fired in the Mike Crater. The cloud reached 20.4km. 35 aircraft participated in the test, including 8 effects aircraft. The Mk-27 was stockpiled from 1958 to 1965 and had a nominal yield of 2 megatons. View 2 | View 3 Navajo - |Redwing| Date: 17:56 UTC 10/07/1956 | Type: Barge | Yield: 4.5 Mt A test of the TX-21C thermonuclear device. Detonated on a barge near the Union crater, 0.4km south of Iroij island. The cloud reached 31km and a diameter of 42.6km. 6 cloud penetration missions commenced 22 to 38 minutes after the detonation. Increased radioactivity was detected on Parry and Enewetok Islands, Wotho and Utirik were only lightly touched by radiation. Waves 3.4m high created by the blast were recorded 29km away on Namu Island, which covered the island 17 minutes after detonation. Navajo was the cleanest U.S. device ever tested. 95% of the yield came from fusion, resulting in relatively low fallout. Tewa - |Redwing| Date: 17:46 UTC 20/07/1956 | Type: Barge @4.5m | Yield: 5 Mt The Bassoon Prime was a 'dirty' three stage design, the first U.S. three stage design. This was the second test of this design, the earlier 'clean' version tested in Redwing Zuni. The fission yield was 87%, the highest known fission yield in any U.S. thermonuclear test. A uranium tamper was used around the tertiary stage instead of the lead tamper used in Zuni. This design was later developed into the Mk-41 bomb, the highest yield weapon ever deployed by the U.S. The crater 1.2km wide and 39m deep. The cloud reached 31km, fallout from the shot blanketed an area of 3,200 square kilometers. clip used by kind permission of Atomcentral.com. High-speed Huron - |Redwing| Date: 18:12 UTC 20/07/1956 | Type: Barge | Yield: 250 Kt A test of the W-50 prototype, a two-stage thermonuclear device. Called 'Egg', its diameter was 39cm, 109cm long, and weighed 360kg. It was the last Redwing shot, and was fired in the Mike crater. Huron was fired when fallout from the Tewa shot, detonated just 24 hours earlier, was still covering the islands. Huron did not add to this fallout. The W-50 warhead was stockpiled from 1963 to 1991 and yielded 60 to 400 kilotons. It was used on the Pershing tactical surface-to-surface missile. Hurons first shot date had to be aborted 3 minutes short of zero because of loss of D-T boost gas pressure in the pit. Boltzmann - |Plumbbob| Date: 11:55 28/05/1957 | Type: Tower @150m | Yield: 12 Kt A test of the XW-40 light weight boosted fission warhead. The device had a total weight of 134kg, the nuclear system by itself weighed 65kg. The width was 45.7 cm, length 80.2 cm. The shot cab held 9 tons of sand, and 15 tons of paraffin as instrument shielding. A balloon was tethered to the roof of the cab by a nylon cord as part of research done into the rope trick phenomena. View 2 Priscilla - |Plumbbob| Date: 13:30 UTC 24/06/1957 | Type: Ballonshot @210m | Yield: 37 Kt A weapons effects test sponsored by the DOD using a stockpiled device of known yield conducted at the NTS. The device used was a Los Alamos designed Mk-15 boosted primary similar to Redwing Lacrosse. It weighed 263kg was 68cm in diameter, and was 69cm long. The primary objective was to correlate these characteristics with its effects on military equipment and materiel. The DOD (AFWSP) conducted 34 scientific projects during the shot, one of the largest effects tests ever at NTS. The test shot was at Frenchman Flats, 500m to the east of a number of concrete mounds used to verify and test structual integrity. View 2 Hood - |Plumbbob| Date: 11:40 UTC 05/07/1957 | Type: Baloon @460m | Yield: 74 Kt The largest atmospheric test conducted in the continental U.S. A test of a two-stage thermonuclear device designed by UCRL (University of California Radiation Laboratory), even though the U.S. government stated at the time that no thermonuclear tests were being conducted in Nevada. It used a boosted Swan primary (which gave yields of 12-19 kt in other tests during Plumbbob). About 7 kt of the overall yield was from fusion. The test also included troop maneuvers by 2500 Marines, and air operations by 124 aircraft. Clip used by kind permission of Atomcentral.com. Fireball | View 2 Diablo - |Plumbbob| - NEW Date: 11:30 15/07/1957 | Type: Tower @150m | Yield: 17 Kt A test of a 2-stage thermonuclear design. A boosted Swan primary was fired in a mock up thermonuclear system. This device was very similar to Shasta. A full yield test of this device was intended for Hardtack I in 1958. The device was 41cm by 174cm, the total weight 613kg. A blue glow can be seen around the cloud caused by intense radiation ionizing the surrounding air, the Eastman film stock used for this clip is sensitive to this effect. High-speed | View 2 John - |Plumbbob| Date: 14:00 UTC 19/07/1957 | Type: Airburst @~3000m | Yield: 2 Kt A combination proof test of the Genie (AIR-2A) nuclear air-to-air rocket, and an effects test of the Genie W-25 warhead. The unguided Genie rocket was fired from a F-89J. The rocket traveled 4.2km in 4.5 seconds (about Mach 3) after release before detonating. A group of five USAF officers volunteered to stand uncovered in their light summer uniforms directly beneath the blast in a public relations exercise. Their experience with the original audio can be seen in this video, and from below them in this video. Kepler - |Plumbbob| Date: 11:50 24/07/1957 | Type: Tower @150m | Yield: 10 Kt Probable test of XW-35 primary in a thermonuclear mock up. Similar to Hardtack I Koa device which was tested at 1.37 Mt in 1958. Kepler had a predicted yield of 11 kt. It had a diameter of 72cm, and a length of 112cm. The primary weighed 29kg, the total device weight was 688 kg. Wide View Owens - |Plumbbob| Date: 13:29 UTC 25/07/1957 | Type: Baloon @150m | Yield: 9.7 Kt Very small boosted plutonium implosion device, progenitor for the XW-51 which later became the W-54, the smallest nuclear warhead deployed by the United States. Main clip used by kind permission of Atomcentral.com. View 2 | View 3 Stokes - |Plumbbob| Date: 12:25 07/08/1957 | Type: Baloon @460m | Yield: 19 Kt A test of the LASL XW-30 multi-purpose warhead; used in TADM (tactical atomic demolition munition), and Talos SAM (surface-air-missile) warhead. All oralloy (highly enriched uranium) DT gas-boosted system. The predicted yield was 10-20 kt. Device diameter 56 cm, length 116 cm. Nuclear system weight 144 kg, total device weight 203 kg. Smokey - |Plumbbob| Date: 12:30 31/08/1957 | Type: Tower @213m | Yield: 44 Kt Test of the UCRL TX-41 thermonuclear design. Three stage prototypes of this design were previously fired in Redwing Zuni and Tewa, this test system was reportedly a two stage device, using a boosted primary in a thermonuclear system mock up. Some fusion yield was produced by secondary. Device dimensions: diameter 127cm, length 320cm, weight 4,267 kg. The Mk-41 eventually became the largest yield nuclear weapon ever developed or deployed by the U.S (25 megatons). It had the highest yield to weight ratio of any known weapon (about 6 kt/Kg). Smoky became notorious due to the radiation exposures received by 3000 servicemen who conducted maneuvers near ground zero shortly after the test. This led to Congressional inquiries and epidemiological evaluation of the affected veterans. Galileo - |Plumbbob| Date: 12:40 02/09/1957 | Type: Tower @150m | Yield: 11 Kt LASL diagnostic/exploratory test of boosted fission device. Device dimensions: diameter 31.5cm, length 152.5cm. Total device weight 385kg. clip used by kind permission of Atomcentral.com. View 2 Coulomb-B - |Plumbbob| Date: 20:05 06/09/1957 Type: Surface | Yield: 0.11 Kt One-point safety experiment of the XW-31. The yield was only 0.2Kt and was considered a failure. 'One-point safety' in nuclear weapons design refers to the requirement that a nuclear warhead must not have a high probability of nuclear detonation if a single point of its high explosive components is accidentally detonated. Specifically, the probability of achieving a nuclear yield greater than a certain threshold must be less than one in a million. This design principle ensures that accidental detonations from events like crashes or fires do not lead to a nuclear explosion. Fizeau - |Plumbbob| Date: 16:45 UTC 14/09/1957 | Type: Tower @152m | Yield: 11 Kt Fizeau was a LASL boosted fission device. Possibly a test of the XW-34 depth bomb. Device dimensions: diameter 40.6cm, length 80cm inches. Total device weight 60kg. Predicted yield 8-10 kt. Newton - |Plumbbob| Date: 12:50 16/09/1957 | Type: Baloon @460m | Yield: 12 Kt LASL test of XW-31 variant, boosted primary in thermonuclear system mock up. Design yield 50-70 kt. Device dimensions: diameter 71 cm, length 99 cm. Total device weight 610 kg. Whitney - |Plumbbob| Date: 16:45 UTC 14/09/1957 | Type: Tower @152m | Yield: 11 Kt Test of a boosted Swan primary in a W-27 thermonuclear system mock up. Charleston - |Plumbbob| Date: 13:50 29/09/1957 | Type: Balloon @460m | Yield: 12 Kt UCRL test of a small "clean" tactical 2-stage thermonuclear device. Device fizzled when second stage failed to fire. Predicted yield was below 50-100 kt. Swan primary used. Device dimensions: diameter 56cm, length 57cm. Total device weight 555kg. Previous page | Next page 1 | 2 | 3 | 4