Arecibo Radio Telescope Collapses

[Sentry]

Age and neglect, plus additional stresses from some recent earthquakes in the few past years have caused an instrument platform support cable to snap in august. Another cable snapped two weeks ago, at which point the decision was made to demolish the array. Two days ago while a drone was observing a support tower, the remaining cables from that tower snapped sending the 900 ton instrument platform into a 500 foot free fall into the dish and jungle floor below.

Pretty wild footage from the camera and drone on site:


And some before and after pics:

[killramos]

I’ll sleep better knowing the financial system is safe from the goldeneye going forward.

[lilmira]

You can see Sean Bean if you enhance

[ExtraSlow]

Something something, jodiefoster-contact.gif

[Thaco]

there's no way you catch that on video as a coincidence

[Sentry]

Not a coincidence, they suspected it was going to fail on its own before they got to demolish it. The drone was performing an inspection on the remaining cables because more and more individual wires were starting to snap at an accelerated rate since the second entire cable failed in mid november.

[D'z Nutz]

Yeah the first cable snapped in August and another snapped last month so they decided they were going to demolish it. Cameras were put there to monitor it cause the thing was on its last legs.

What a shame

[spikerS]

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there's no way you catch that on video as a coincidence

They were contemplating repairing it, but decided not to as there was no safe way to do it without putting the people repairing it in danger. Cables were already snapping.

They were even contemplating suspending repair crews from helicopters to try and shore up the receiver part of the antennae lol. Could you imagine?!?! Would take a pilot with super human skill to keep it steady enough for the crew member dangling below.

They knew it was just a matter of time before it collapsed, and it just beat them to the punch before they could demolish it. They knew it was gonna happen quickly.

[e31]

They still haven't found out who struck the Sea-to-Sky Gondola twice, and here we are with another cable based infrastructure failure... This can't be a coincidence.

[Buster]

Looks like the BF3 map now!

[ThePenIsMightier]

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there's no way you catch that on video as a coincidence

To have that footage of the literal failure out of the hundreds of hours it held on by a thread is incredibly unlikely... But I guess not impossible.

[ExtraSlow]

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They still haven't found out who struck the Sea-to-Sky Gondola twice, and here we are with another cable based infrastructure failure... This can't be a coincidence.

BC ecoterrorists going big time?

[mazdavirgin]

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there's no way you catch that on video as a coincidence

The failure was fairly predictable in the sense they had already lost one cable and the design didn't allow for the structure to survive on the remaining 3 cables. I mean you can see the signs of the 3rd cable slowly failing. All those missing strands and paint flakes are bad signs of impending failure. Also if I recall a few minutes prior pinging noises were reported due to another strand pulling out. So it's likely the drone was sent up to inspect the result of the missing strand/noise. High tension cables experiencing failure is not a quiet event. It's extremely loud.

[flipstah]

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I’ll sleep better knowing the financial system is safe from the goldeneye going forward.

Die another day

[blueToy]

Its sad to see it self destruct, but that's a lot of weight to support for over 50 years without any major upgrades. Amazing that they just caught the event as it happened. Hopefully,
they can find the resources to rebuild soon. Thanks for posting it.

[ExtraSlow]

Does it seem like that's not a 900 ton platform? I mean, it's heavy, but, not 900 tons.

[blueToy]

I might be wrong here but I read once it was about 400 tons.

[ExtraSlow]

Some crane and rigging guys can tell me. But as a professional "not that kind" of engineer and without ANY technical details I'm saying the platform weighs less than 100 tons.

[mazdavirgin]

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Some crane and rigging guys can tell me. But as a professional "not that kind" of engineer and without ANY technical details I'm saying the platform weighs less than 100 tons.

It's ~900 tons the cables are a lot thicker than they look like in the pictures and there's a lot more of them than people realize. About 18 3.25 inch steel cables...

Suspended 450 feet above the reflector is the 900 ton platform. Similar in design to a bridge, it hangs in midair on eighteen cables, which are strung from three reinforced concrete towers. One is 365 feet high, and the other two are 265 feet high. All three tops are at the same elevation. The combined volume of reinforced concrete in all three towers is 9,100 cubic yards. Each tower is back-guyed to ground anchors with seven 3.25 inch diameter steel bridge cables. Another system of three pairs of cables runs from each corner of the platform to large concrete blocks under the reflector. They are attached to giant jacks which allow adjustment of the height of each corner with millimeter precision.

https://www.naic.edu/ao/telescope-description

Arecibo Observatory’s telescope consists of a radio dish 1,000 feet (305 meters) wide in diameter with a 900-ton instrument platform hanging 450 feet above. The platform is suspended by cables connected to three towers.

https://www.nsf.gov/news/news_summ.jsp?cntn_id=301674

[AndyL]

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Some crane and rigging guys can tell me. But as a professional "not that kind" of engineer and without ANY technical details I'm saying the platform weighs less than 100 tons.

Are you including the liquid helium cooling baths for all the equipment mounted up there too? 160kg/m³ starts adding up pretty quick.