Time for a little reflection people for our fellow servicemen and woman:

‘Hydro-acoustic anomaly’ raises possibility that missing Argentine submarine exploded

A “hydro-acoustic anomaly” was detected near where the Argentinian submarine ARA San Juan went missing, three hours after it sent its last communications a week ago, the navy revealed on Wednesday. The anomaly occurred at 30 nautical miles north of the last position from where the submarine had communicated with the navy, spokesman Enrique Balbi said.

A US institute detected the anomaly, but only informed Argentina about it now. Balbi had earlier said it was unlikely the submarine exploded, because an explosion of that magnitude in the sea would not have gone undetected......

The spokesman said three navy vessels were on their way to the area to check whether the submarine was there. “It’s a noise. We don’t want to speculate” about what caused it, Balbi said of the anomaly......

Argentina has accepted help from Russia in the search for a military submarine that went missing with 44 crew in the southern Atlantic a week ago.



President Mauricio Macri said the Russian leader, Vladimir Putin, had phoned him to offer to deploy a survey vessel and crew with experience of similar operations.

It has been mentioned that the Argentine sub captain reported that they had taken 2 tons of seawater down the snorkel (maybe due to severe weather) which had caused short circuits in the battery, though the captain said that these had been routine and managed. She then submerged on passage, again perhaps due to the bad surface weather, as this type of sub is noted for being particularly uncomfortable in bad weather on the surface. After this, nothing has been heard. Would leave the suspicion that the batteries later malfunctioned due to the seawater ingress, either releasing chlorine gas, or catching fire or even exploding. Any of these occurring underwater would be disastrous. The above 'hydro-acoustic anomaly' would be constant with this.

The submarine community has always been very close. I was privileged to be at Lancaster University for the 100 year ?? celebration of the RN Submarine Service (which was off-the-scale awesome, given the attendance of submariners from across the planet) not long after the loss of the Kursk. A retired Russian Yankee class Captain presented and it prompted a quick whip round for the relatives...several thousand went in the hat in a few minutes.

Terrible time for the families, one hopes for a miracle, but time is so short and the job (of searching the ocean floor) is so big. Not good.

Marcantilan,
I was there in 82, ASW was my speciality.
In all of my years service, I never had to do a Submiss/Subsunk for real, thank God.
My thoughts are with the men and the families of those on board.

What I find astonishing is that there isn't an EPIRB hit. Surely there are mechanisms in place to release an EPIRB automatically or manually when something disastrous happens? The same difficulty in finding the missing Malaysian airlines flight is something surely we can overcome with today's technology very simply?
Narrowing the search area with a pinging EPIRB would lead search assets directly to the last known point of contact.

They do have EPIRBs. Plus other means of signalling from underwater such as barrels that release smoke and water-stains.

Argentine Navy informed an US Agency noticed a violent noise (possible explosion) on Wednesday, 30 nm of the last reported ARA San Juan position.

This is not looking good at all.

Manually - yes, it's already been reported that the submarine has 2 EPIRBS.

The problem with an automatic system is, how does it "know" something disastrous has happened? It needs to be sufficiently self-contained to continue working in the event of a major systems failure onboard the submarine, yet well enough integrated to be able to figure out when to deploy. Even if you solve those non-trivial problems, the consequences of "false positive" deployment are very serious, even in peacetime.

Best wishes and hopes to those onboard, and to those engaged in the SAR operation, for a successful outcome.

Voyager RRR2881 airborne out of CRD,northeast towards ASI possibly..

or an implosion?

If implosion, it would have be off the continental shelf in deep water.

Looks like it is going into Montevideo

https://www.irishtimes.com/news/worl...rine-1.3302480

I have thought, since the first news of it being missing, that the singular lack of a distress beacon has pointed to an unfortunate and unexpected end to the submarine not long after its last communication. In any other scenario, they'd have released the beacon.

IIRC there have been cses where a released beacon has remained entangled in the sub and never made it to the surface....

This is not looking good

The Argentine navy says an event consistent with an explosion was recorded near where a submarine disappeared last week with 44 crew on board.
An "abnormal, singular, short, violent, non-nuclear event" had been detected in the south Atlantic, a spokesman said. The information came from an Austria-based anti-nuclear test watchdog, Capt Balbi said. It follows a report of a loud noise in the same area.

The new information was provided to the Argentine navy on Thursday by the Vienna-based Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO), Capt Balbi said.

In a statement, the CTBTO said two of its hydro-acoustic stations had detected a signal from an "underwater impulsive event".

On Wednesday the navy received a US report of a "hydro-acoustic anomaly" detected hours after the submarine went missing. Capt Balbi said the suspected explosion took place near the submarine's last known location. The navy only knew the location of the suspected explosion, not its cause, he said. Search efforts would be concentrated in the area, he said.

I watched the press conference, one of the advantages of being a Spanish speaker. Sobering.

One journo asked if the sub could have been attacked by a third party. Fortunately, their officer said that was in no way the case....

https://m.youtube.com/watch?v=CVYNOrFK3B4

The above link is a doc on underwater sub/event tracking using acoustics. Only a week to sort out an event in the vast oceans is still amazing after Craven did it in 1968 using research hydrophones to find Scorpion. Good companion book is Blind Man’s Bluff which details the sub events of the 60’s and on.

Tweets emanating from Argentina that I am following now indicate that the AA have announced that the 44 crew are lost. I have not yet found confirmation, but the sources are good.