Operation Redwing - 1956 Mohawk - 02/07/1956 Operation Redwing, conducted at both Enewetak and Bikini atolls, was a 17 shot testing series testing thermonuclear devices too large to test at the Nevada Test Site. Redwing was an open series, meaning members of the media and press were allowed to observe the shots. This was the first time an open series had been held at the Pacific since Operation Crossroads in 1946. Redwing’s purpose was primarily for weapons development, however, weapons effects tests had been carried out mainly during the Cherokee event. Smaller and lighter devices were tested, sometimes at the expense of efficiency. Operation Castle’s total yield output was 48 megatons, more then double the amount predicted. Due to the large amount of radioactive products released by Operation Castle in 1954, Redwing was put on a yield budget. The maximum allowable yield for the 17 shots was 20 megatons. The actual total yield of Redwing was 20.82 megatons, 6-10 megatons of that came from fission, less than Castle Bravo’s fission output. Redwing proof tested the Mk-28 warhead and the first three-stage thermonuclear device. Most of the devices tested during Redwing were scaled down ‘clean’ versions. However, some ‘dirty’ ones were also tested, such as Flathead (June 12, 1956) and Tewa (July 21, 1956). Some very small tactical nuclear warheads were also tested during Redwing. Some devices had diameters as small as 13 cm. Devices from both the Los Alamos and UCRL laboratories were tested, often with much dispute about the sharing of the energy budget put on Redwing. Testing was organized and conducted by Joint Task Force 7 (JTF 7), a combined military and civilian operation. Military personnel, Federal civilian employees, and contractor personal from the Department of Defense and Atomic Energy Commission made up JTF 7. In addition, several thousand from the AEC, few from other government agencies, and foreign observers were present. The test names are all American Indian tribes. The UCRL devices were names for birds and musical instruments. Numerous technical experiments were carried out in conjunction with each of the 17 shots. These experiments measured the yield and efficiency of each shot, as well as gauged military effects of the explosions. Most of the Navy support group was located at Bikini, where its ships served as living space during evacuations of the atolls. The majority of the tests were conducted either twenty or fourty minutes before sunrise, as at this time the atmosphere was more likely to be cloud free. Tewa device |Bassoon Prime| Animal testing was conducted during shots Lacrosse, Erir. Mohawk, Cherokee, Zuni and Navajo to study chorioretinal burns as the result of viewing the fireball. Rabbits and monkeys were exposed in holding devices so their eyes looked at the burst point. - Video of animal testing Testing was also conducted concerned with checking the effect of multimegaton devices on buildings. Six steel-frame, industrial-type buildings constructed on Iroij and three manmade islands were instrumented and exposed to the positive phase of the Cherokee blast. - Effects Testing One minute before shot time, personnel with high-density goggles were instructed to put them on. Goggles were not to be removed until at least 10 seconds after the initial blast, and then only gradually, to accommodate the light change. Those without goggles were to face away from zero point, shield their eyes, and not view the fireball until at least 10 seconds after the burst. Personnel were instructed not to look at the fireball with binoculars at any time and were warned that sunglasses were not to be used in lieu of high-density goggles, as they would afford no protection against the light Of the fireball. The highlight of Redwing was the Cherokee event. Cherokee was the first U.S. air drop of a thermonuclear weapon. This was a response to the Soviet Union’s successful air drop of a two-stage thermonuclear weapon in 1955. Weapons Effects studies during Redwing were centered on Cherokee but many failed due to a bombing error by the B-52 that dropped the bomb. The intended ground zero was directly over Namu Island, but the flight crew mistook an observation facility on a different island for their target. The bomb detonated some 6.5 km off target over the ocean northeast of Namu. - Click on a thumbnail for a larger version Test Shots Video Name Yield Date |UTC| Type Warhead Location LAT/LONG Lacrosse 40 Kt 18:20 04/05/1956 Surface @5m TX-39 Off Runit Isl.- Enewetak 11.55780 162.35500 Cherokee 3.8 Mt 17:50 20/05/1956 Airdrop @1325m TX-15/39 Off Namu Isl.- Bikini 11.66830 165.39420 Zuni 3.5 Mt 17:56 27/05/1956 Surface @3m TX-41 Eninman Isl.- Bikini 11.49670 165.36920 - Yuma 0.19 Kt 19:56 27/05/1956 Tower @60m - Aomon Isl.- Enewetak 11.62000 162.33000 Erie 14.9 Kt 18:15 30/05/1956 Tower @90m TX-28c Runit Isl.- Enewetak 11.54440 162.36440 Seminole 13.7 Kt 00:55 06/06/1956 Surface @2m TX-28 Bogon Isl.- Enewetak 11.67640 162.22220 Flathead 365 Kt 18:26 11/06/1956 Barge @4.5m Off Yurochi Isl.- Bikini 11.60000 165.45140 - Blackfoot 8 Kt 18:26 11/06/1956 Tower @60m - Runit Isl.- Enewetak 11.55110 162.35860 - Kickapoo 1.49 Kt 23:26 13/06/1956 Tower @90m - Aomon Isl.- Enewetak 37.13860 -116.11780 Osage 1.7 Kt 01:14 16/06/1956 Airdrop @210m XW-25 Runit Isl.- Enewetak 11.62000 162.33000 - Inca 15.2 Kt 21:26 21/06/1956 Tower @60m XW-45 Rujoru Isl.- Enewetak 11.63000 162.35000 Dakota 1.1 Mt 18:06 25/06/1956 Barge TX-28c Off Yurochi Isl.-Enewetak 11.60280 165.45140 Mohawk 360 Kt 11:55 02/07/1956 Tower @90m - Eberiru Isl.- Enewetak 37.13860 -116.11780 Apache 1.85 Mt 18:06 08/07/1956 Barge XW-27 Ivy Mike crater-Enewetak 11.67140 162.20030 Navajo 4.5 Mt 17:56 10/07/1952 Barge TX-21c Off Yurochi Isl.-Bikini 11.66330 165.38720 Tewa 5 Mt 17:46 20/07/1956 Barge TX-41 Off Namu/Yurochi Isl.-Bikini 11.67390 165.33940 Huron 250 Kt 18:12 20/07/1956 Barge XW-50 Off Flora Isl.- Enewetak 11.67190 162.36920