BBC now reporting the grim news.....


San Juan submarine: 'Explosion' dashes crew survival hopes - BBC News

Such tragic news for their families and colleagues, and for their country as a whole.

Indeed our thoughts are with Marcantilian and the Argentine people.
I have been following this thread hoping so much for a better outcome.
Truly tragic.

The boat was cut in half in order to carry out the refit, might the welding be up to scratch following rejoin? Could see implosion a possibility if not.

I was hoping and hanging on for a miracle here. So sorry to hear this news.

CTBTO direct link in English
 

Wonder then why they didnt pick it up when MH370 hit the water eventually...?

As you perhaps know, the CTBTO sensors did pick up an acoustic event of interest:

Curtin researchers in search for acoustic evidence of MH370 - News and Events | Curtin University, Perth, Western Australia

Further analysis determined that the event was probably a false lead:

https://motherboard.vice.com/en_us/a...n-more-missing

Kinda reminds me of the Vela satellite double flash incident in 1979 which at the time was deemed publically to be a false alert:

https://en.wikipedia.org/wiki/Vela_Incident

Anyway, with the current missing sub there is probably closely held acoustic data from SOSUS arrays and undersea platforms that may be shared discreetly to aid in the search and investigation.

What is the design crush depth for this type of Submarine?

When the wreckage is found....and it will be....ROV's will be able to determine if it was an explosion or an implosion based upon the forensic examination of the hull rupture(s) I would assume.

The Sea is an unforgiving thing.....sad news.

Just as we have found the air to be SAS. Shipyard I worked at always had a reading of Psalm 107:23-31 during the ceremony prior to the launching of a new vessel. Sadly not to be for these 43 men and one woman.

Anyone know if they carry HTP fuelled torpedoes?

Thanks a lot. We (the average Argentine) sincerely appreciate the help of all the countries navies / air forces and, also, the condolences of people all over the world. Thanks really, this is a very sad moment of the country. And for me personally.

About the torpedo load, it is classified info, but in the last pictures of the boat (in Ushuaia Naval Base) you could see one SST-4 torpedo in the torpedo room. So you could assume the sub has at least two torpedoes.

Regards,

I can shed some light on this. The SST-4 IS A German torpedo of the same generation as Tigerfish and just as unreliable. Electrically powered and for anti surface ship only. Normal load out is 18 fish.

I don't believe for one second that the issues of when it deploys automatically can't be overcome with today's technology. And false alarms are actually very common place for EPIRB activiation on other platforms such as Yachts, ships, etc.
Why was MH370 EPIRB never detected?
Any kind of catastrophic end for an aircraft should, simply trigger the EPIRB release that will be detected by satellite giving it's crash position.
This never happened for MH370.
This has happened with other commercial and military aircraft, notably some of the North sea helicopter crashes.
It seems to me that the current system of EPIRBS on aircraft and now perhaps Subs is fatally flawed and needs urgently reviewing.

False alarms on peacetime/civilian vessels are pretty minor, and might not take much more than a phone call to clear up. It's a somewhat bigger deal when your EPIRB accidentally deploys on a vessel that's trying to hide; bear in mind that, even in peacetime, submarines generally don't want to be located.

What if an automated EPIRB accidentally deploys on a SSBN? Oops, that's your nuclear deterrent compromised, especially if your adversary is then able to home in and start capturing your acoustic signature. What if you've got a SSN snooping around somewhere it shouldn't be? Again, an accidental EPIRB deployment is going to be a pretty big deal.

And for what benefit? If the San Juan incident is what it's starting to look like, it seems unlikely that an automatically-deployed EPIRB would have done the crew much good anyway...

Pasta, thanks I'm very aware of submarine ops and there need for secrecy and stealth both in peace and conflict.
There must still be a way to allow for automatic release that is secure enough for one to not to just fall off and self deploy!
And yes in this case it may seem unlikely that any kind of rescue would have been possible, however knowing the exact location of the distress would have saved a lot of effort and risk to a huge search force mustered from all over the world.
Having an accurate last known position is vital for not just saving lives but saving time, money and risk to others.

Having been affiliated with the US Navy for a while and developing admiration for Submariners in particular as a result of coming to know quite a few of them....starting with Diesel Boaters who during the time of a Nuclear Submarine Force era were a special breed all to themselves....it is times like this that makes one pause to consider the tragedy of the loss of a Boat and Crew.

It matters not which Navy....as all who venture out upon and under the Oceans are bound by shared experiences and dangers.

I pray the families, friends, and fellows of those lost find peace as they grieve for those who perished in this tragedy.

https://www.youtube.com/watch?v=ZKMEl4HU0fA

Great words and I think this tragedy as with the Kursk unites nations because we all sense the loss in such circumstances

Is there any chance that the explosion detected does not necessarily mean the terrible end for the sub crew?
If not, sincere condolences to families, friends and colleagues.

Well stated, SASless.
I'm deeply saddened by this tragic event.

Thank you. I started the engineering part of my life in torpedo R&D in the 1950s.
I know it's a bit off topic but I am astonished that, in this computerised age, so many torpedo designs fail to perform as well as wished.
Sidon and Kursk were sunk by HTP motor explosions. I'd guess, with modern electric battery technology, that unstable fuels would be passé.

Me too. Even military people who have at some time been made by their governments to become our enemies are someone's father, son, brother, or, as in the case, daughter or sister.

My thoughts are with them.

The crew of the ARA San Juan, eternally 'on patrol'. RiP and condolences to their families and friends.

If a EPIRB deployed automatically following a total AC failure would that give rise to unintended deployment? Would a manual 'inhibit' switch, subject to a rigid cross check procedure for On and Off, operated during electrical change overs, prevent inadvertent deployment?


Would a system of sea water activated EPIRBs, with the activation switch inside the submarine, say forward, mid ships and aft, with a deliberate delay function for, say, 90 seconds after the switch becomes immersed, (to allow for a manageable situation to be initiated), be workable, delay function overridden if an AC failure occurs? With todays computer technology surely such an integrated system should be possible, still allowing for fully manual deployment availability, if required?


(Not at all familiar with the AC/DC distribution and operation in submarines!)

The Kursk was sunk by an explosion related to the Shkval torpedo, really an undersea rocket capable of traveling 160 MPH underwater. No way could that be done with electric propulsion.

Jon

Is there a reference source for that? It is the first time I've seen the Shkval mentioned as a factor in this disaster.
The Russians have not been particularly forthcoming about the specifics of this accident, but the idea of a peroxide leak cascading to a warhead explosion was the agreed story afaik.

Yes, it’s the only plane capable of moving the DSRV out of NAS North Island. San Diego, CA. Even with the new engines, it’s a heavy haul with a few stops or air refuelings.

GF

I thought the DSRVs were out of service and replaced with The US Navy -- Fact File: Submarine Rescue Diving and Recompression System (SRDRS)
Or do folks just still refer to the new system as a DSRV?
Just curious in view of this truely sad event.

Well, the reason the US was shadowing the exercises so closely is they were hoping, I guess, to monitor a test using the Shkval torpedo.
A lot of speculation at the time of the Kursk disaster was that something went wrong with preparing a Shkval for launch. Not sure whether the official story is to be completely believed, Russia has had a bit of a reputation for bending the truth. Anyway, there does seem to be a new story about this. Here's some old info that was current at the time:
(Well, can't post the link, it won't let me, so...)
search for : theguardian 2001 kursk.russia and select "what really happened"
So, maybe looks like what I THOUGHT I knew was wrong, again.

On the other hand, HTP is also quite nasty stuff, and if it comes in contact with a hydrocarbon fuel, well BANG!

Jon

I can tell you that the SST-4 had nothing to do with the sinking of ARA San Juan. In 1982 the MoD tried to obtain data on its capabilities from its manufactures in Germany. They politely declined. More later.

When ARA Santa Fe was damaged in South Georgia and before it was subsequently scuttled a number of its SST-4 fish were unshipped and sent to the UK for evaluation. The results made the Mk24 Tigerfish look good.

When Argentina bought its three subs in the late 70s, the SST-4 was part of the deal.

In regards to what happened, I can only suggest a theory.

She took on water through a Snorkel failure. This caused battery damage which led to a power failure while submerged. With 2 tons of sea water on board and despite blowing main vents, without electrical power the outcome was inevitable. Without power, the bilge pumps could not clear the influx and gravity did the rest.

Snorkel failure - HMS Affray springs to mind.

Old Duffer

Navaleye,

Four Thousand pounds of Sea Water overcame the buoyancy available by blowing all Tanks....Main and Negative and Trim?

As we know of the problem....doesn't that mean the Boat was on the surface or close enough to get off a message to their HQ which in turn told them to return to Port.

Why would the Boat remain submerged or leave the surface knowing they had the problem they did?

It is a US Navy policy that in the event of possible/known contamination of Batteries by Sea Water....the Boat surfaces and remains surfaced. One US Sub did that and actually sent crew members topside while they ran the Aux Diesel to ventilate the Boat.

Admittedly, we do not know of the actual situation and are only relying upon what has been published in News Reports....but from what is being said....a lot of my Submariner buddies are very curious about what did happen.

They also reminded us the "remaining oxygen (breathing time)" being quoted is for the full crew in a single compartment or shared environment. Meaning....if only some of the crew survived and are trapped...but have full access to air and devices to alleviate fouling of the air then there might be a longer period for survival but other issues come into play....being in cold water submerged....it gets very cold.



Background Information on RN Submarines and Snorkeling.


http://rnsubs.co.uk/dits-bits/articl...-snorting.html


Article on the HMS Affray loss.

http://www.hmsaffray.co.uk/portrait_of_a_disaster.htm

SASless,

As you rightly point out we simply don't know and wont know until the wreck is found. Every theory postulated including mine is a guess however well informed. Hindsight is also a wonderful thing, but...

If I were the skipper of that boat, knowing I had taken in two tons of oggin through a dodgy snorkel I would not have dived it. I would have stayed on the surface and issued an SOS. Something catastrophic happened very quickly.

My thoughts are with them all.

Regarding the missing Argentine Submarine, it's something that hits home for me, as my older brother was a submariner in the RN back in the 80s and 90s (serving aboard both HMS Sovreign and HMS Swiftsure). He'd be out on patrol for three months at a time with no communication, and when he came home we'd get no prior notice of that either. The sub would return to Guz (Devonport), he and a few shipmates would pile into a single car and drive non stop to our house in the North East (about 500 miles) where they would all dump their laundry for my mum to clean whilst they drank the local pub dry, and finally all collapse unconscious for a day on the floor of our living room. They'd stay for a couple of days before dispersing to their own homes and a few weeks later would all pile back in to the same old car and steam it back to the Base. It took him a day or two to mentally 'decompress' after the relentless routine of life aboard a sub, it's not cushy by any stretch of the imagination. He loved the service life though, and signed up for a full 22 years stint. Sadly a back injury whilst training for the Devonport team for 'Field Gun' put an end to his Naval career. I have no doubt if he had stayed in the Navy he would be a Fleet Chief Petty Officer by now, he was already rising rapidly through the ranks.

So I have every sympathy for the families of those missing aboard the Argentine Sub. When they leave for the sea, you hear nothing until either they turn up on your doorstep, or an officer in full dress uniform does. In the worst of all cases a journalist turns up to break the news. Sailors are Sailors no matter what country they serve, and their families share a common bond.

Yes, once woke up, heard something on bedroom radio, shot out of bed, happened to look out of window and the black car was parked outside a neighbour's house. Serving mil but still a shock.

They couldnt travel on suface with up to 8 m waves in the area.

That's why I originally asked about the implosion, if it took on water then the striking of the bottom may have caused several or all of the compartments to fail and implode.

Hello Navaleye!

I think Telefunken gave some info to the RN back in 1982. I have certain docs about it.

The SST-4 torpedoes were introduced in the Argentine Navy in 1974, being its first users the two IKL-209/1200 (ARA San Luis and ARA Salta, the latter still "operative").

ARA Santa Fe (ex USS Catfish - modernized to Guppy II standards) was not armed with SST-4 (nor its tubes allowed a swim out torpedo like SST-4). It had a mixed load of Mk.14 and Mk.37 mod. 3 torpedoes.

Back to ARA San Juan, according to the Navy it had a load of training torpedoes (no warhead).

Regards!

What’s your background in commanding diesel submarines?

Eternal Father, strong to save,
Whose arm hath bound the restless wave,
Who bidd'st the mighty ocean deep
Its own appointed limits keep;
Oh, hear us when we cry to Thee,
For those in peril on the sea!

Sad to see that they are still, and shall ever be, on patrol. :{

Vaya con Dios, amigos.