Questions
1. Name two argument the US government used
to convince the American people of the need for
the nuclear weapon test program
2. What means “Duck and Cover”?
3. What was the main purpose of Operation
Crossroad; what was the test site and how
many tests were performed
The Nuclear Test Program:
probing the Nature of the Blast
Blast—40-60% of total energy
Thermal radiation—30-50% of total energy
Ionizing radiation—5% of total energy
Residual radiation (fallout)—5-10% of total energy
The results of the weapons test programs
 Efficiency of explosion
 Kind and shape of blasts
 Blast effects, range & damage
 Thermal effects
 Radiation effects
List of US atmospheric Bomb tests
Operation
Year
Location
#
Crossroads
1946
Bikini Atoll
2
Sandstone
1948
Enewetak Atoll
3
Ranger
1951
Nevada Test Site
5
Greenhouse
1951
Enewetak Atoll
4
Buster-Jangle
1951
Nevada Test Site
7
Tumbler-Snapper
1951
Nevada Test Site
7
Ivy
1952
Enewetak Atoll
2
Upshot-Knothole
1953
Nevada Test Site
11
Castle
1954
Bikini Atoll
Enewetak Atoll
6
Teapot
1955
Nevada Test Site
14
Wigwam
1955
Pacific Ocean
1
Pacific Atolls and Nevada desert areas
Project 56
1955
Nevada Test Site
4
Redwing
1956
Bikini Atoll
Enewetak Atoll
17
Plumbbob
1957
Nevada Test Site
30
Project 58
1957
Nevada Test Site
2
Project 58 A
1958
Nevada Test Site
2
Hardtack I
1958
Bikini Atoll
Enewetak Atoll
Johnston Island
35
Argus
1958
South Atlantic
3
Hardtack II
1958
Nevada Test Site
37
Nougat
19611962
Nevada Test Site
32
Dominic
(with Fishbowl)
1962
Christmas Island
Johnston Island
Central Pacific
36
Storax
(with Sunbeam
and Roller
Coaster)
19621963
Nevada Test Site
Nellis Air Force Range
56
316 tests until October 10, 1963; Limited Nuclear Test Ban Treaty
Classification of atmospheric tests
 Surface Blast:
fireball in touch with surface
vaporization of surface structures through blast
and firestorm, immediate radioactive fallout
 Low Altitude Air Blast:
fireball < 100,000 ft (without touching ground)
generates shock waves, pressure difference
artificial for large areal damage, sea battle
 High Altitude Air Blast:
fireball > 100,000 ft (>3000m)
interrupts satellite based communication
through electromagnetic pulse (EMP)
Surface Tests
Operation Sandstone
Up to 1948, all four Plutonium bombs (Trinity, Fat Man,
and the two Crossroad tests ) had been identical, based
on a conservative wartime design. The Sandstone test
series introduced a second generation of weapon
design by evaluating several new design principles. All
three shots were performed on a 200ft tower level.
The original Fat Man design used a solid plutonium
core, surrounded by a natural uranium tamper. The
Sandstone devices had a gap between tamper and core
to achieve a more efficient compression of the core.
They apparently retained a solid core however.
The pure plutonium core was replaced by Pu-U alloy
enriched in 235U. Three tests, X-Ray, Yoke, and Zebra
used differently designed cores and tampers of varying
thickness.
Efficiency: Operation Sandstone
Operation Greenhouse
The Greenhouse Test Series was conducted at Enewetok Atoll in April and May of
1951. It consisted of four high yield tests - Dog, Easy , George, & Item performed on
a 300ft tower altitude. Dog and Easy were proof tests of two new strategic bombs
the Mk 6 and Mk 5, respectively. George & Item were the first tests of thermonuclear
fusion, testing the principle of "fusion boosting", using a thermonuclear fusion
reaction to inject neutrons into a fission core to boost the efficiency for fission.
George 10ms
George 20ms
George 30ms
Damage :Operation Greenhouse
Model
10 ms
20 ms
30 ms
225 kT GEORGE test
Operation Greenhouse
Nevada Test Site
Operation Plumbbob
Operation Plumbbob was conducted at the Nevada Test Site (NTS) from May
through October of 1957. It consisted of 29 tests. This series addressed several
objectives, including tactical weapon proof tests, safety tests, and component
and mockup testing for thermonuclear systems. The tests were performed at
surface and low altitude levels. One important test component were military
exercises involving 16,000 DOD personnel called Desert Rock VII and VIII.
Hood was the largest atmospheric test
ever conducted at the Nevada site. The
test was performed at 1500 feet altitude.
Hood was a two-stage thermonuclear
device with a predicted yield of 60-80 kt.
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.
Medical and Military tests:
Operation Plumbbob
Test
Rainier
Early underground test, at depth level of ~900ft
In a tunnel excavated underneath Rainier Mesa
The extreme heat and pressure of
an underground nuclear explosion
vaporizes the surrounding rock,
forming a cavity. Further away, there
are zones of crushed, cracked, and
irreversibly strained rock. Cavity
collapses forming a crater at surface
Test Name
Time and Date (GMT)
Location
Test Type
Height (Ft)
Yield - Actual (Predicted)
Sponsor
Purpose
Comments
Boltzmann
11:55 28-May-57
NTS, Area 7c
Tower
500
12 kt (11 kt)
LASL
WD
XW-40 boosted fission warhead test
Franklin
11:55 2-Jun-57
NTS, Area 3
Tower
300
140 Tons (2 kt)
LASL
WD
Fizzle, XW-30? boosted all-oralloy fission
warhead test
Lassen
11:45 5-Jun-57
NTS, Area 9a
Balloon
500
0.5 Tons (600 Tons)
UCRL
WD
Fizzle, unboosted all-oralloy small weapon design
Wilson
11:45 18-Jun-57
NTS, Area 9a
Balloon
500
10 kt (8 kt, 2-12 kt)
UCRL
WD
XW-45X1 Swan test, gas-boosted composite pit
Mk-15/39 primary, stockpiled device of known
yield
XW-31 1-point safety test
Largest atmospheric test at NTS, 2-stage
thermonuclear device
Priscilla
13:30 24-Jun-57
NTS, Area 5
Balloon
700
37 kt (40 kt)
LASL/DOD
WE
Coulomb-A
17:30 1-Jul-57
NTS, Area 3h
Surface
0
Zero (1-2 Lb)
LASL
ST
Hood
11:40.00.4 5-Jul-57
NTS, Area 9a
Balloon
1500
74 kt (60-80 kt)
UCRL
WD
Diablo
11:30.00.1 15-Jul-57
NTS, Area 2b
Tower
500
17 kt (11-15 kt)
UCRL
WD
2-stage device, some thermonuclear yield
John
14:00 19-Jul-57
NTS, Area 10
Rocket
18,500
1.7 kt (1.7 kt)
DOD
WE
W-25 warhead for Genie air-to-air missile
Kepler
11:50 24-Jul-57
NTS, Area 4
Tower
500
10 kt (11 kt)
LASL
WD
XW-35 ICBM warhead development, primary in
thermonuclear mockup
Owens
13:30 25-Jul-57
NTS, Area 9b
Balloon
500
9.7 kt (2-10 kt)
UCRL
WD
Very small boosted plutonium device, XW-51
progenitor
Pascal-A
8:00 26-Jul-57
NTS, Area 3j
Shaft
-485
Stokes
12:25 7-Aug-57
NTS, Area 7b
Balloon
Saturn
1:00 10-Aug-57
NTS, Area 12c
Shasta
12:00 18-Aug-57
Doppler
Pascal-B
LASL
ST
1-point safety test
1500
Listed as "slight", about 55 tons
(predicted 1-2 Lb)
19 kt (10-20 kt)
LASL
WD
Tunnel
-100
Zero (100 Lb)
UCRL
ST
NTS, Area 2a
Tower
500
17 kt (11-15 kt)
UCRL
WD
12:30 23-Aug-57
NTS, Area 7
Balloon
1500
11 kt (-)
LASL
WD
22:35 27-Aug-57
NTS, Area 3c
Shaft
-500
0.3 kt (1-2 Lb)
LASL
ST
XW-30 test, all oralloy gas-boosted system
1-point safety test of XW-45X1, oralloy-Pu
composite core filled with helium; first shot fired in
Ranier Mesa tunnel
Nearly identical to Diablo, DT gas boosted Swan
primary
Gas boosted implosion device, possible XW-34
test
1-point test for upper limits of safety, similar to
Pascal-A
Franklin Prime
12:40 30-Aug-57
NTS, Area 7b
Balloon
750
4.7 kt (2 kt)
LASL
WD
Smoky
12:30.00.1 31-Aug-57
NTS, Area 8
Tower
700
44 kt (45-50 kt)
UCRL
WD
TX-41 2-stage device, some thermonuclear yield
Galileo
12:40 2-Sep-57
NTS, Area 1
Tower
500
11 kt (-)
LASL
WD
Wheeler
12:45 6-Sep-57
NTS, Area 9a
Balloon
500
197 Tons (200 Tons)
UCRL
WD
Coulomb-B
20:50 6-Sep-57
NTS, Area 3g
Surface
0
0.3 kt (1-2 Lb, 20 Tons max)
LASL
ST
Laplace
Fizeau
13:00 8-Sep-57
16:45 14-Sep-57
NTS, Area 7b
NTS, Area 3b
Balloon
Tower
750
500
1 kt (1.5-2 kt)
11 kt (8-10 kt)
LASL
LASL
WD
WD
Newton
12:50 16-Sep-57
NTS, Area 7b
Balloon
1500
12 kt (50-70 kt)
LASL
WD
Rainier
16:59.59.5 19-Sep-57
NTS, Area 12
Tunnel
-899
1.7 kt (-)
UCRL
WE
Whitney
12:30 23-Sep-57
NTS, Area 2
Tower
500
19 kt (15 kt)
UCRL
WD
Charleston
13:00 28-Sep-57
NTS, Area 9
Balloon
1500
12 kt (less than 50-100 kt)
UCRL
WD
Morgan
13:00 7-Oct-57
NTS, Area 9
Balloon
500
8 kt (2-10 kt)
UCRL
WD
Boosted fission device, exploratory test
Retest of redesigned Lassen device, possible
XW-51 air-to-air warhead progenitor
1-point test for upper limits of safety, similar to
Coulomb-A, all-oralloy gas boosted
Fleegle device: all-oralloy gun-type weapon
XW-34 test, boosted fission device
Test of XW-31 variant, boosted primary in
thermonuclear system mockup
Deep underground test shot, modified W-25
warhead
Test of boosted Swan primary in W-27
thermonuclear system mockup
Clean tactical 2-stage thermonuclear device, 2nd
stage failed to fire
XW-45X1 test, boosted Swan primary and
Flamingo secondary
Retest of Franklin with more U-235 added to core
Operation Upshot-Knothole 1953
This operation took place in 1953 at the Nevada Test Site. It exposed exercise
personnel to nuclear tests, and thus to radiation in considerable amounts.
Observations of troop formations and exercises were conducted at what was
calculated to be the minimum safe separation distance, with many personnel being
exposed to multiple tests. Present exposure limits would be 3.3 rems over the 11
week operation. Approximately three thousand soldiers reached or exceeded this limit,
with 84 exceeding the annual limit (the highest recorded exposure was 26.6 rem).
An estimated 18,000 DOD personnel participated in observer programs, tactical
maneuvers, scientific studies,
and support activities.
The 280 mm Nuclear Gun
The Atomic Cannon, at 280 mm, was the largest nuclear capable mobile
artillery piece manufactured by the United States. On May 25, 1953 the Army
successfully fired an atomic shell from the World War II vintage 280mm gun,
which detonated 160 meters above ground at a distance of 7 miles at the
Nevada Test Site. The resulting 15 kt GRABLE explosion not only symbolized
the addition of a new weapon to the Army's arsenal, but also symbolized the
beginning of the atomic era for the Army. This shot was the first detonation of
a gun-type atomic bomb since the bombing of Hiroshima on 06 August 1945.
Atmospheric tests at low & high altitude
 High Altitude Air Blast:
fireball > 100,000 ft (>3000m)
 Low Altitude Air Blast:
fireball < 100,000 ft (without touching ground)
Operation Dominic
Operation Dominic was a series of 36 nuclear
test explosions conducted in 1962 in the
Pacific. This test series was scheduled to
respond in kind to the Soviet resumption of
testing after the 1958-1961 test moratorium.
Most of these shots were conducted with freefall bombs dropped from B-52 bomber aircraft.
Twenty of these shots were to test new
weapons designs; six to test weapons effects;
and several shots to confirm the reliability of
existing weapons. An additional component
was the use of the Thor missile for lifting
warheads into near-space to conduct high
altitude nuclear explosion tests; these shots
were collectively called Operation Fishbowl.
Test Name
Adobe
Aztec
Arkansas
Questa
Frigate Bird
Yukon
Mesilla
Muskegon
Date
25 April 1962
27 April 1962
2 May 1962
4 May 1962
6 May 1962
8 May 1962
9 May 1962
11 May 1962
Location
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Pacific Test
Christmas Island
Christmas Island
Christmas Island
Yield
190 kilotons
410 kilotons
1090 kilotons
670 kilotons
600 kilotons
100 kilotons
100 kilotons
50 kilotons
Swordfish
11 May 1962
off San Diego
<20 kilotons
Encino
Swanee
Chetco
Tanana
Nambe
Alma
Truckee
Yeso
Harlem
Rinconada
Dulce
Petit
Otowi
Bighorn
Bluestone
12 May 1962
14 May 1962
19 May 1962
25 May 1962
27 May 1962
8 June 1962
9 June 1962
10 June 1962
12 June 1962
15 June 1962
17 June 1962
19 June 1962
21 June 1962
27 June 1962
30 June 1962
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
Christmas Island
500 kilotons
97 kilotons
73 kilotons
"Fizzled"
43 kilotons
782 kilotons
210 kilotons
3 megatons
1.2 megatons
800 kilotons
52 kilotons
"Failed"
Unknown
7.65 megatons
1.27 megatons
Starfish Prime
9 July 1962
Johnston Atoll
1.4 megatons
Sunset
Pamlico
Androscoggin
Bumping
Chama
Checkmate
Bluegill Triple
Prime
Calamity
Housatonic
10 July 1962
11 July 1962
2 October 1962
6 October 1962
18 October 1962
20 October 1962
Christmas Island
Christmas Island
Johnston Atoll
Johnston Atoll
Johnston Atoll
Johnston Atoll
1 megaton
3.88 megatons Successful advanced principles test of high-efficiency thermonuclear weapon.
75 kilotons
11.3 kilotons
1.59 megatons
7 kilotons
Operation Fishbowl, high altitude nuclear explosion, 147 km altitude, XM-33 Strypi rocket
Operation Fishbowl, high altitude nuclear explosion, 50 km altitude, Thor missile, W50
410 kilotons
warhead, fireball formed, large disruption of ionosphere did not occur
800 kilotons
8.3 megatons Last US air dropped nuclear device
Operation Fishbowl, high altitude nuclear explosion, 97 km altitude, Thor missile with W-50
410 kilotons
warhead, dramatic aurora-like effects, extensive ionosphere disruption, radio communication
over central Pacific disrupted for over three hours
26 October 1962 Johnston Atoll
27 October 1962 Johnston Atoll
30 October 1962 Johnston Atoll
Kingfish
1 November 1962 Johnston Atoll
Tightrope
4 November 1962 Johnston Atoll
1–40 kilotons
Note
Polaris A2 Missile launched from the submarine USS Ethan Allen.
RUR-5 ASROC from USS Agerholm (DD-826) at a range of only 4,000 yards.
Operation Fishbowl, exoatmospheric at 400 km altitude, caused artificial aurora borealis and
power outages in Hawaii
Operation Fishbowl, 21 km (69,000 ft) altitude, Nike Hercules missile with a W31 warhead,
test of a missile defense system, regarded to be the last true U.S. atmospheric nuclear test
Low Altitude Tests
SWANEE, 97kT; B52 parachute fall 3000ft
r = 685 ft ≈ 228 m
Pressure surge downward, shock
front emission: Fireball evolution
R = 110
W0.4
YESO, 3000kT; B52 drop free fall to 8300ft
[ft] (W = yield in kT of TNT) r = 2705 ft ≈ 900 m
Development
of the Airburst
3 s: double shock-front
upwards motion
0.5 s: Shock-front fireball evolution
10 s-30 s: Surge
and stem evolution
1.2 s: Shock-front re-bounce
Altitude Test Delivery Systems
B-52 Stratofortress
The B-52 can carry a wide assortment of offensive weapons including conventional
"iron bombs," four nuclear bombs, and a variety of missiles such as the ALCM (airlaunched cruise missile) and the SCRAM (short-range attack missile). Four Skybolt
ballistic missiles were mounted on the wings of the B-52H, though this missile was
not put into production. Two Hound Dog missiles were mounted under the wings of
the B-52H. The Hound Dog is really a small jet-powered airplane with a range of up
to 700 miles and a maximum speed of over Mach 2.
AMARC, Phoenix, Arizona, U.S.A. Airplane,
Junk, Yard, Recycle, Aircraft, Boneyard