This analysis is one-way submarines die:LOSS OF THE ARGENTINE SUBMARINE SAN JUAN

Once again, my Brothers and Sisters, the members of ISA/USA send our condolences to our colleagues in Argentina.

We thank Bern Jeraca who sends this excellent Acoustic Report

This analysis is one-way submarines die:

ANALYSIS OF ACOUSTIC DETECTION OF THE LOSS OF THE ARGENTINE SUBMARINE SAN JUAN

By Bruce Rule

An analytical review of all information released by the Comprehensive Nuclear-Test-Ban Treaty Organization on the acoustic signal associated with the loss of the Argentina Submarine, ARA SAN JUAN confirms the following:

That acoustic signal originated near 46-10S, 59-42W at 1358Z (GMT) on 15 November 2017. It was produced by the collapse (implosion) of the ARA SAN JUAN pressure-hull at a depth of 1275-feet. Sea pressure at the Collapse depth was 570 PSI. The frequency of the collapse event signal (bubble-pulse) was about 4.4 Hz.

The energy released by the collapse was equal to the explosion of 12,500 Pounds of TNT at a depth of 1275-feet. That energy was produced by the nearly instantaneous conversion of potential energy (sea-pressure) to kinetic energy, the motion of the intruding water-ram which entered the SAN JUAN pressure-hull at a speed of about 1800 mph.

The entire pressure-hull was destroyed (fragmented/compacted) in about 40 milliseconds (0.040s or 1/25th of a second), the duration of the compression phase of the collapse event which is half the minimum time required for cognitive recognition of an event.

Although the crew may have known collapse was imminent, they never knew It was occurring. It is reasonable to assume the sailors did not drown or experience pain. Death was instantaneous.

The SAN JUAN wreckage sank vertically at an estimated speed between 10 and 13 knots. Bottom impact would not have produced an acoustic event detectable at long range.

The open question is: why was no corrective action - such as blowing ballast - taken by the SAN JUAN crew before the submarine sank to Collapse depth? According to Argentine Navy spokesman Gabriel Galeazzi, the Commanding Officer of the SAN JUAN reported a "failure" in the submarine's "battery system," The time of that report was 0730 on 15 November, assumed to have been GMT. Subsequently, the problem was reported to have been "fixed." The SAN JUAN intended to submerge and Continue its transit north. The SAN JUAN pressure-hull collapsed at 1358 GMT on 15 November.

In the case of the loss of the US nuclear submarine SCORPION (SSN 589), hydrogen out-gassed by the main battery exploded at 18:20:44 GMT on 22 May 1968 incapacitating/killing the crew with an atmospheric over-pressure in the battery well estimated to have been 7-10 times the fatal value. The pressure-hull was not breached. This assessment was based on analysis of acoustic detections of the event and damage observed in pieces of the fragmented battery recovered from the wreckage at a depth of 11,100 feet by the US submersible TRIESTE, e.g., microscopic, spectrographic and x-ray diffraction analyses. (There was no flooding of the pressure-hull before the battery exploded.) SCORPION lost power and sank slowly over nearly 22 minutes to collapse at a depth of 1530-feet at 18:42:34 GMT on 22 May 1968.There is the possibility that a similar sequence of events occurred Aboard the SAN JUAN. If the wreck is located and efforts are made to recover components; emphasis should be placed on the battery system.


The author of this assessment was the lead acoustic analyst at the US Office of Naval Intelligence for 42 years, analyzed acoustic detectors of the loss of the USS THRESHER (SSN 593) on 10 April 1963 and testified Before that Court of Inquiry. The author expresses his appreciation to those who supported this assessment with research and calculations.



How do you detect the distant sound of an exploding submarine?

When the ARA San Juan went missing off the coast of Argentina, a global network of highly-sensitive listening posts designed to track nuclear explosions was called into service

By Eleanor Peake Wired Magazine

Monday 27 November 2017




The Argentinian fleet of Submarines

It only takes 11 underwater sensors to listen to all the oceans on the planet. When something as small as a submarine vanishes, this ability to listen out for relatively tiny sounds becomes crucial.

This was the case of the ARA San Juan submarine, which last made contact with the Argentinian naval authorities on November 15. The submarine was making a routine sailing from Ushuaia in the south of Argentina to the northerly port of Mar del Plata when it vanished.

A week of searching followed, but with no success. Then, on November 23, the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO) detected an explosion off the coast of Argentina, in the same spot where the submarine was last detected.

Although the San Juan was 6,000 kilometers from the nearest sensor on Ascension Island, the CTBTO was able to detect a tiny spike in sound waves that indicated a small explosion. "In the case of the Argentinian submarine, looking for an explosion signal this small was like looking for a needle in a haystack," says Lassina Zerbo, Executive Secretary of CTBTO.

Zerbo and his team also worked to detect the missing MH370 Malaysian airplane that went down in 2014. "For months we were working, at points, we would think we had a signal, we would send people to check, and it would just be an old ship." This time, however, the International Monitoring System was successful in detecting a small explosion, providing the beginning of an answer to the families of the 44 crew onboard.

But how did they do it?

What is the Comprehensive Nuclear-Test-Ban Treaty Organisation?

The CTBTO set up the International Monitoring System Network in 1996 as a means of holding the world's nuclear powers to account. The network listens out for vibrations 24 hours a day, and it's impossible for a major explosion to happen without the CTBTO noticing.

Today, the CTBTO has 337 monitoring systems on and off the land, spanning every continent and every ocean. While the network constantly monitors for any sound that could indicate a nuclear launch or explosion, in recent years its role has shifted. It now listens to marine life, earthquakes, and disappearances at sea. For that, it uses a network of just 11 hydrophone stations.

How do hydrophones work?

Hydrophones are sensors that look like microphones. They are placed at various points in the ocean and deployed in threes to make it easier to determine which direction sound waves are coming. The hydrophones detect changes in water pressure and convert these changes into electrical signals.






Cable connecting hydrophones to an onshore hydrophone station

CTBTO Public Information, www.ctbto.org

The hydrophone stations are some of the most expensive monitoring mechanisms in existence. The most recent hydrophone station to be built was completed last year off the coast of the Crozet Islands in the Southern Indian Ocean and cost $34 million.

The CTBTO also has T-Phase monitors, which track seismic movements rather than hydro-acoustic sound waves. The seismic monitors track the pressure and impact of the movement underwater rather than just the sound frequency, giving the CTBTO a better understanding of an explosion's impact.

Computers at the onshore monitoring stations then record the signals from the hydrophones and transmit them to various satellites. These satellites then transmit the data to the International Data Centre in Vienna, Austria.

Analysing the data

The Centre receives ten gigabytes of data a day from its monitoring stations. Data is analyzed, filtered and then searched for sound spikes. "We knew from the media attention that a submarine had disappeared, so we were able to look in a smaller area," says Zerbo. "This small signal would not usually catch our attention."






Image is taken from CTBTO website detailing the locations of the hydroacoustic sensors

"Knowing that our sensors can catch any noise under the water, be it an explosion or just the submarine hitting the seabed, we set about sweeping all the data we collected," he explains. This process took six days. Experts were told to focus on the smallest signal or impulse that could be an indication of any underwater explosion associated with the time and location of the submarine.

The Centre was forced to write and rewrite the programming script used by the monitors in order filter the data appropriately. "We weren't even sure if they were looking for a small explosion or just the burst of the submarine engine," Zerbo says. Eventually, a short, single anomaly was detected, indicating an unusual, non-nuclear event.



Frequency of the explosion detected before and after the San Juan submarine lost signal

CTBTO Public Information, www.ctbto.org

The team concluded this was made by the missing submarine, although quantifying the magnitude of the explosion is tricky. "Estimating a possible magnitude is even more difficult because this sound has propagated over a large distance from the source location to the receiver, but this is something that the engineers and scientists are currently still working on," the CTBTO said in a statement on Friday.

Thanks Bud



John Bud Cunnally ETC (SS) Ret. USN – President

International Submariners Association of the U.S.A. (ISA/USA)

4704 Coppola Drive

Mount Dora, Fl 32757-8069

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My deepest condolences to the families who lost loved ones in this horrible and tragic submarine explosion; and my deepest gratitude to all who serve our country, nation and world, to make our world safer to enjoy life within. Huge hugs to you all.
Love, Respect & Prayers Always,
AbbyL

 

Interesting article, though no pics came over.

 

Pics seem to be lost for now. Working on How they got lost.

 

Hell of a way to check out. Prayers to the submariners.

 

At least, as the article stated, death was instantaneous. No suffering.

 

Not exactly the case, they all knew the end was near, they suffered fear of the next moment, fear for their loved ones and for their shipmates.

Folks that write such stuff do it for the survivors, others in the Submarine Service know better.

 

Have a album, items numbered, now how to relate to the text?

 

Pretty much!

 

Rest looks good, thanks

 

Middle boat is definitely American. I originally enlisted into the Navy as a "sub volunteer". Missed the grade average limit by 1.5%, so I bombed out in BE&E. Switched to Comm Electronic Tech, and was assigned to an ASW frigate. So, subs were "targets".
I was pleased. After talking with some "bubbleheads", being in a sub didn't seem so good an idea. I like my fresh air.....

 

ARA San Juan (S-42) - Wikipedia

Has a update on the loss

 

Boomer for sure or NOT.