Christmas Island, Johnston Island,
Central
Pacific - 1962
The Soviet Union had abrogated the 34 month old de facto
nuclear testing moratorium on 1 September 1961 by initiating an
unprecedented series of atmospheric nuclear tests. The initial U.S.
response was to commence its own test series (Operation Nougat) two
weeks later. Nougat was an underground series however, restricted to
very low yield devices.
Numerous atmospheric tests, many at high yield, were of course on the
drawing board at the weapons labs, some carried over from planning for
previous test series. Official U.S. action on convening its own
atmospheric series did not begin until 10 October 1961 when President
Kennedy approved planning for one. Final approval was given on 2 March
1962, 7 weeks in advance of the first planned test.
Dominic included 36 tests. The majority of the tests (29 airdrops) were
weapons development tests, intended to evaluate advanced designs that
the labs had been cooking up during the years of the moratorium and
before. Five rocket-launched tests were conducted to gather further
weapons effects data on high-altitude phenomena. Two tests of
operational weapon systems were conducted - the Polaris submarine
launched ballistic missile and the ASROC anti-submarine rocket.
Conducted as part of Operation Dominic was a series of high altitude
tests known as Operation Fishbowl. These tests were Thor missile
launched warheads detonated at very high altitudes (30-248 miles) to
evaluate the destructive mechanisms and effects of high yield explosions
against ballistic missile RVs. Several test failures occurred with
missiles being destroyed in flight by range safety officers when
electronics failed (Bluegill), when rocket motors malfunctioned
(Starfish and Bluegill Prime), or when the missile veered out of control
(Bluegill Double Prime). The Bluegill Prime test was particularly
disastrous since the missile was blown up while still on the launch pad,
requiring complete reconstruction of the demolished and plutonium
contaminated Thor launch facility.
| Test: |
Frigate Bird |
| Time: |
23:30 6 May 1962 (GMT) |
| Location: |
Johnston Island |
| Test Height and Type: |
SLBM Airburst; 11,000 Feet |
| Yield: |
600 kt |
| Device Diameter (inches): |
18 |
| Device Length (inches): |
46.6 |
| Device Weight (lb.): |
717 |
Frigate Bird was the only US test of an operational ballistic missile with a
live warhead. This test involved firing a Polaris A1 missile from a ballistic
missile submarine. The missile was launched by the USS Ethan Allen
(SSBN-608) at 13:18 (local) from a position 1500 nm east-northeast of Christmas
Island. The re-entry vehicle (RV) and warhead flew 1020 nm downrange toward
Christmas Island before re-entering the atmosphere 12.5 minutes later, and
detonating in an airburst at 11,000 feet. The system tested was a combination of
a Polaris A1 SLBM, and a W-47Y1 warhead in a Mk-1 RV. The Mk-1 RV had a
beryllium heat-sink heat shield, and with the 717 lb warhead had a gross weight
of 900 lb. The missile/RV demonstrated an accuracy on the order of 2200 yards.
This warhead had a yield-to-weight ratio of 1.84 kt/kg, but the higher yield Y2
variant tested in Dominic Harlem doubled the yield and nearly doubled the YTW
ratio to 3.61 kt/kg.
The image of the Frigate Bird mushroom cloud was taken through the periscope
of the
USS Carbonero (SS-337)
480 nm ENE of Christmas Island. The Carbonero
(along with the USS Medregal, SS-480) was within 30 miles of the burst
point.
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