The 6000-Foot Underground Nuclear Bomb that Cracked an Entire Island

Project Cannikin was part of a series of nuclear tests aimed at testing the effects of underground nuclear detonations that dated back to the early 1960s.

This top-secret American operation aimed to test the powerful LIM-49 Spartan anti-ballistic missile. Previous detonations had taken place at Amchitka Island in Alaska, but none would be as destructive as the Cannikin nuclear explosion.

On November 6, 1971, one of the world's most powerful nuclear warheads was placed in a hole some 6,000 feet below the ground.

The island had been evacuated, and while the project's personnel impatiently waited for President Richard Nixon's approval, a small crew of civilians headed towards the island in an heroic attempt to stop the proceedings.
However, it was too late…

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Dark Footage showcases the most unbelievable photos and videos from history while telling the stories behind the camera. Featuring military, space, aircraft and real-life historic events caught on tape.

[popsbents]

I was on one of the two destroyers assigned to patrol the area around the island to ensure that Green Peace was kept clear. Reportedly they were on a small fishing vessel and with the weather conditions there was no way they were going to be there. The ride on the destroyer was one of the worst I have experienced including typhons. We had a ladder that went from the main deck to the 01 level torn off along with many other items. The Xo wanted to layup prior to returning to our homeport and make the ship look pretty, but the CO said keep going let them see what we went through.

[Jay]

They never mentioned a crack on the island, which the title of the video states. :|

[FlintIronstag]

The irony is the Cannikin W71 warhead test was for a weapon that was never needed. The Spartan missile was part of the Safeguard anti-ballistic missile defense system. Billions were spent building an ABM base in North Dakota with 100 Spartan and Sprint missiles. One day after reaching full operational capability, Congress voted to decommission the base. It was deemed to be ineffective with the development of Soviet MIRV technology.

[sneeringimperialist]

Lifted an area 2 miles wide, 16 feet high, 6000 feet deep. That's a lot of power! Like 4 cubic miles of rock!

[fairwinds]

The telemetry from the Cannikan test was relayed through Naval Communication Station Kodiak; I was there and witnessed the whole thing thanks to the video cameras at Amchitka Island. We later learned that the sea-otters that lived around Amchitka had their eardrums permanently damaged, preventing them from diving for food and causing them to starve en-mass.

[chrishewitt]

My uncle flew Canberra bombers for the RAF. He flew through the mushroom clouds in Australia to take samples for scientists. Using the samples they could calculate the yield of Russian bombs by comparison with a known source.
Operations Mosaic, Hot Toddy/Unsparing, Buffalo and Antler

[anonymousforprivacy]

"made no radioactivity"
"produced polonium, americium, and other elements"
me, having taken undergraduate chemistry
"I see something inherently wrong with this statement"
Edit: a lot of y'all seemed to miss my point. It produced these materials, but they're taught as generally radioactive in most isotopes.

[pirobotbeta]

The configuration of the test chamber was to 'blame' for the devastation.
Spherical chamber, most of the air pumped out to simulate 'edge of atmosphere' testing.
It was big, with targets at various distances from the gadget.
Vacuum didn't absorb any radiation from the shot, a 'dark-flash' did not occur.
Dark-flash:
Air close to the nuke absorbs initial x-ray flash; heavily ionized air becomes briefly opaque to all light.
'Dark Air' absorbs almost all energy from the nuke, super-heats and expands into a fire-ball.
Without much air in the chamber, there was no dark-flash.
The walls of the chamber were vaporized by direct radiation, something that was not planned for.
Test chamber had a very large surface area; lots of material exposed to the heat of a Star.
The chamber was suddenly pressurized with hundreds of tons of super-heated rock vapor and plasma.
In the blink of an eye, the vapors and plasma cooled, dropping pressure in the chamber to near vacuum.
But the surrounding rocks have already been shoved aside by the blast; inertia carries million of tons of rock away from the blast for a brief moment.
Rebound is swift and violent; a huge cavitation bubble made of stone collapses, the shock waves reverberate for long minutes.
Nobody has used large vacuum-cell testing with nukes since.

[richardfranklin]

I lived on the island for a couple of years in the early 90s. The island is a pristine nature preserve. All the animals flourish on the island. There are 100's of Bald Egals, 1000's of otters, Salmon running in the streams and the lakes are full of fish.

[DarylChambers]

FYI: metres per second is a unit of speed measurement. Acceleration is measured in metres per second per second or m/s/s or m/s²

[stumpyjoe]

I get that things need to be tested but I hate when the destruction kills off so much wildlife. That fact was the darkest part of the video (to me). Love your content across all the channels. The way it’s packaged still keeps me interested :)

[pierremontpetit]

I like how you neutralize your tone and teaxt letting the people chose the good/bad view of the scenarios that you talk about. 🎯 you're on point.

[michaelhowell]

I've always thought it was "Operation Plumb-bob" instead of "plum bomb".

[sgtbrown]

can you imagine the power it took to lift literally a mile square block of earth 60 feet in the air?

[vice.nor.virtue]

3 times in this video you said "footage clearly shows" - but then there was no footage of the thing you claimed was clearly being shown.

[tsepheletseka]

Wow. 7.0 on the Richter Scale. That has to be hands down the most powerful man-made earthquake ever recorded.

[ImmortalTreknique]

Quality content as always my good sir
😁👍💪👊🍻

[timhayes]

I just have to wonder if setting off huge nuclear explosions in the "Ring of Fire", just does not seem real smart.

[GrizrazRex]

I was on Amchitka on 6/30/72; perhaps one of the last non-resident civilians to ever visit. The Reeve Aleutian L188 continued onward to Attu, then back to Shemya for an overnight stay. We returned to Anchorage via Adak, the next day. Things on Amchitka were still winding-down, at the time. By 1975, Amchitka no-longer appeared as a destination in Reeve timetables.

[fredfernald]

Governments with nukes are like kids with firecrackers, just can’t help from playing with their toys.