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M 3.9 Experimental Explosion – 147 Km ENE of Ponce Inlet, Florida

earthquake.usgs.gov

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Re: M 3.9 Experimental Explosion – 147 Km ENE of Ponce Inlet, Florida

#11

Post by jandrewrogers »

bijowo1676 wrote: post #6
jballanc wrote: post #3

Earlier quoted context omitted.

This is almost certainly what it was. Wiki even has a photo of the USS Gerald Ford undergoing blast tests off of Ponce Inlet, and mentions that it registered as a M3.9 quake: https://en.wikipedia.org/wiki/USS_Gerald_R._Ford#Operational... If I had to guess, this is probably the USS John F. Kennedy: https://en.wikipedia.org/wiki/USS_John_F._Kennedy_(CVN-79)

I dont understand the purpose of using 40,000 lbs of TNT (0.2 kilotons) that registers as M3.9 quake - what kind of explosive payload is it simulating? the only thing that comes to mind, is the smallest yield settings of a modern tactical nuke B61-12

The structure is engineered to survive a multitude of conventional threats intact. It is testing properties of the design rather than specific weapons per se. Also, these tests are intended to be non-destructive which impacts their design.

Exercises where the US military uses decommissioned aircraft carriers and other large ships as targets are illustrative. They are basically unsinkable. You can hit them with torpedoes, bombs, missiles, etc all day. At the end of the exercise they usually have to send over a specialized demolition crew to actually scuttle the ship. Astonishingly damage resistant.

A nuke would of course do the trick but now you are playing a different game.

People chronically underestimate how difficult it is to get enough conventional explosive on target to sink a major naval vessel, even ignoring the extensive active defenses.

Re: M 3.9 Experimental Explosion – 147 Km ENE of Ponce Inlet, Florida

#12

Post by jandrewrogers »

walrus01 wrote: post #8
bijowo1676 wrote: post #6

Earlier quoted context omitted.

I dont understand the purpose of using 40,000 lbs of TNT (0.2 kilotons) that registers as M3.9 quake - what kind of explosive payload is it simulating? the only thing that comes to mind, is the smallest yield settings of a modern tactical nuke B61-12

I would guess that they want to simulate a percentage of the shock force of a near miss or hit from a (russian, chinese, other equivalent-tech) torpedo or naval mine without actually risking rupturing the hull. So they need a much greater weight of explosives positioned a much further distance away than if they were to actually fire a torpedo at the ship. Or for general shake and vibration and shock force testing of…

I would guess they want a large enough explosion to generate peak acceleration of the entire ship without a local enough explosion to actually damage it. Getting enough separation to make it non-local requires a lot of explosive thanks to the inverse cube law.

If you look at e.g. seismic damage models, peak acceleration is correlated with most of the worst outcomes.

Re: M 3.9 Experimental Explosion – 147 Km ENE of Ponce Inlet, Florida

#13

Post by pfdietz »

hankbond wrote: post #7
walrus01 wrote: post #4

Earlier quoted context omitted.

They also periodically use live munitions on decommissioned ships, sinking them, for the purposes of validating all sorts of stuff. https://www.pacaf.af.mil/News/Article-Display/Article/452930... https://en.wikipedia.org/wiki/USS_Juneau_(LPD-10)

So, tactical ocean trash?

Steel in the ocean disappears in a century or two. Look at all the rusticles draping off the wreck of Titanic. Bacteria are eating the metal and making slime.

Re: M 3.9 Experimental Explosion – 147 Km ENE of Ponce Inlet, Florida

#15

Post by dboreham »

jandrewrogers wrote: post #11
bijowo1676 wrote: post #6

Earlier quoted context omitted.

I dont understand the purpose of using 40,000 lbs of TNT (0.2 kilotons) that registers as M3.9 quake - what kind of explosive payload is it simulating? the only thing that comes to mind, is the smallest yield settings of a modern tactical nuke B61-12

The structure is engineered to survive a multitude of conventional threats intact. It is testing properties of the design rather than specific weapons per se. Also, these tests are intended to be non-destructive which impacts their design. Exercises where the US military uses decommissioned aircraft carriers and other large ships as targets are illustrative. They are basically unsinkable. You can hit them with torped…

Falklands war shows otherwise.

Re: M 3.9 Experimental Explosion – 147 Km ENE of Ponce Inlet, Florida

#18

Post by andai »

jfaat wrote: post #17
andy_ppp wrote: post #16

Earlier quoted context omitted.

Wait until you hear about industrialised farming, even mass production of crops are killing plenty of animals…

Is your point that that makes this better?

Well it's kinda whataboutism, but I made a similar comment on a video about an environmental crime (a copper mine had dumped an entire lake's worth of toxic sludge into a valley).

The author of the mini documentary said something about how deeply disturbed he was and how he really thought humans were better than this.

I thought that was kind of funny since, yeah the sludge lake is nasty as hell (and if the dam holding it back breaks, it's not gonna be good), but I had to think, maybe he should visit a factory farm for his next video.

That's a far worse horror, and regular folks contribute to it every day without thinking. (I forget the exact number, but something like 80+ billion animals live through that every year.) So I think it should get a little more attention.

(Not vegan, just think we shouldn't be awful towards animals.)

Re: M 3.9 Experimental Explosion – 147 Km ENE of Ponce Inlet, Florida

#20

Post by jandrewrogers »

dboreham wrote: post #15
jandrewrogers wrote: post #11

Earlier quoted context omitted.

The structure is engineered to survive a multitude of conventional threats intact. It is testing properties of the design rather than specific weapons per se. Also, these tests are intended to be non-destructive which impacts their design. Exercises where the US military uses decommissioned aircraft carriers and other large ships as targets are illustrative. They are basically unsinkable. You can hit them with torped…

Falklands war shows otherwise.

How so?

The ships sunk in the Falklands War were all less than half the displacement of a typical US Navy destroyer. The sole exception is the Belgrano, which was built in the 1930s!

The ship being tested here is ~25x the size of the largest British ship that was sunk. Generally speaking, there is a super-linear relationship between ship size and the amount of explosive required to sink it. There is mountains of empirical data on this that you are choosing to ignore.

Every military knows this. They are making a tradeoff between size, which makes the target more difficult to destroy and easier to defend, and the number of ships they can build which allows them more flexibility in force projection.

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