US Nuclear sub has hit an unknown object in the South China sea
 

11 sailors are reported injured but it is still operational and heading for Guam.

https://www.bbc.co.uk/news/world-us-canada-58838332

Probably bumped into Godzilla.

Was it French? Asking for a friend...

This is of concern. I would have imagined that on board tech would detect and avoid such collision. More information required.

They would not be using sonar. It is a nuclear boat on patrol - they just navigate using onboard IMU and charts. A collision with an uncharted object is always a risk - look up USS San Fransisco incident.

Who would put it past the Chinese to string a load of old shipping containers or build artificial reefs, etc across likely sub routes .

I'm curious as to why this incident was publicised.

Mentioned in the above link.

Why release it? well I suppose it does tell China in no uncertain terms they have nuclear subs sitting off the coast in case things get hot regarding Taiwan, so it serves two purposes, to be open and also to send a subtle message, which judging by the the quote below they got, that would be my guess, Plus you might need to explain an unscheduled arrival at Guam and people being taken to hospital.


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Just to put a little more meat on what TS already posted...submarines are normally passive on patrol. An inert uncharted object is therefore undectable, so no concerns from that perspective.

If it was emitting any sort of noise, or was a charted feature, everything changes. Unlike on the tele prog "Vigil" (unmitigated 100% unwatchable, unforgivenly insane, infantile f******** horse manure) submarines do not surface under Bulk Carriers (or if they ever do someone is losing their command and getting Court Martialed).

That was the point at which I finally lost it with "Vigil"....I twigged straight off that the listening sonar guy was useless, a trained one would have heard any powered ship coming from miles away (and be able to tell exactly what type it was). Everyone in that control room should have instantly known he was hopeless and he'd have been replaced straight off.

I suspect as said above the reporting of this early (before the sub appears somewhere unexpected for repairs) is to send a message.

Agreed - Vigil was a steaming pile of hoop.

Unfortunately the BBC thinks that the public won't notice.

Adding even more meat…

Passive sonar is the norm for U.S. subs during all operations (including surface ops). Active sonar is reserved for training and ice ops. However, passive sonar has its limitations; e.g., degrades with speed or poor environmental (acoustic) conditions.

The fact that there were injuries indicates the sub was operating with significant speed.

While subs can measure depth of water under the keel using a fathometer (a routine exception to passive ops), such measurement suffers from the same limitation as the older aircraft GPWS systems; i.e., it can only look down, not ahead. I suspect the SCS is well surveyed with very few uncharted bottom features.

Regarding the comment about surfacing under bulk carriers, large vessels can be extremely difficult to detect using passive sonar due to an effect called a bow null.

The San Francisco collision was due to navigating by incomplete charting data. Back in 1977, the USS Ray collided with the sea bottom due to gross navigational error while operating in the Med. Anyone remember Omega?

OMG, are you saying that a fictional Drama TV series isn’t actually accurate? Here I was thinking that it was. Shame on me.

Now, to be slightly more polite, I understand your frustration at some (a lot) of the nonsense in Vigil, let alone the required modern love story that is required to obtain production funding in today’s Politically sensitive funding environment. However, it was an ok series, not great, but ok.

I put my “civi” eyes on and “mil BS Filter” (especially the poor construction of the boot neck headwear (sorry calling it a beret when they are so inaccurately shaped, pains me - we all have our triggers)) and managed to enjoy it.

On a more realistic note, here is hoping that all of the crew heal well and get back on guard soon.

The USN are reported in The Times today as stating "it was not another submarine" so some kind of Chinese chicanery sounds highly likley.

Spoiler Alert.

Did said sonar guy not turn out to be the saboteur?

The Chinese don't have to bother. Shipping companies lose enough containers already to create a growing hazard.

I'd imagine the sub sea charting accuracy useful to a submarine at depth would be far less than desired. In 1973 operated on board a hydrographic vessel and were surveying waters that had not been updated since Captain Cook did the original, what was surprising was how damn accurate his surveys were using what we would consider rudimentary navigational aids, sextant, and chronometer with no time update from the BBC. Even a survey is no guarantee, as its accuracy is dependent on the technology used, we had a bulk carrier tear its bottom open on a rock pinnacle in open ocean shallow surveyed waters, the rock was slap bang in the middle between the lines that had been run, forget the exact spacing of the lines, in the order of a couple of hundred yards and before the days of side scan sonar.

Well we can only make basic assumptions based on what navy reported.

-Seawolf class are still top notch despite their age and way more advanced in electronics passive detection compared to 668(i). On certain technologies they are still more advanced than the succeeding Virginia class (at least the 1st batch).
- It seems very unlikely for this part of the world not to be very well charted.
- the reported casualties is low compared to the S.F incident, the sub went back on own power.
- Seawolf class have an publicly reported “silent speed” of 20kts and a top speed in the 35-40kts range. If operating close to the bottom (for thermocline stealth or spec ops ) it’s very unlikely it would be operating at more than a few kts, and would have a very precise keel-floor mesure. Running at PD the damage would be mostly on the sail, and striking a civilian traffic would have probably be reported as such.

To clarify on some other comments:
Chinese DO know that U.S subs operate in these waters, since they are still free of navigation based on international laws (even if claimed).
Submarines DO NOT operate in peace time in territorial waters submerged, this is considered an act of war, rightfully so. In these instances, they sail on surface displaying regular navigation light and identification. There are some few exceptions and mutual agreement in place (for some straights and closed water access, and joint exercises).
Chinese are well known to be implementing their own SOSUS system, it is unclear as to how efficient this system is.

I’d bet on either uncharted obstacle, Chinese anti-sub obstacles they would have laid down, or sub-sub collision, even if they claim it’s not the case. If it’s nothing serious, some data will probably be declassified once the navy investigation and report is complete.

anyway, CO,XO and OOD are probably heading to Hawaii for a non-biscuit coffee meeting, and their next command is probably a lighthouse…

Exactly. In reality he woudn't have lasted 5 minutes on the job and certainly not after missing a ship that size. Active listening is one of the most important jobs on the sub!

You need to read up on what the Swedes find in their waters - and certainly without any agreement.

An x-submariner looks at it

My last sailboat had downward sonar (depth gauge) and forward looking sonar for going into an anchorage. I assume these low current devices are not stealthy. I can understand a sub switching these off in time of war or when in foreign waters and wanting to be stealthy, but why not use them for the rest of the time? Obviously I am a pilot who can sail, but not a submariner! But is there a balance between safety and stealthiness?

Even in peacetime, attack submarines spend their time doing stuff they don't want anyone else to see. How better to practice tracking and getting into position to attack an adversary, than doing it for real? How better to gather sonar and other data on your counterpart's vessels and capabilities? This is no secret; everyone's doing it, everyone knows everyone's doing it, and there are some pretty good books on the subject.

I should imagine the holy grail of underwater warfare is being able to track and take out your adversary's SSBNs, so you can bet there's a lot of effort going into this; if anyone does have that capability, you're not going to read about it for a very long time...

Please list some of these pretty good books. Thanks

"The Silent Deep" by Jinks and Hennessey is the most comprehensive account I've read; if you're only going to read one book about submarines, this would be my recommendation.
"Blind Man's Bluff" is also a pretty good read, a bit lighter, with more of a focus on cable-tapping operations.

Pasta is correct - all submarine arms spend their time trying on sneaking around. TF reminds us of the Soviet navies efforts in Sweden and of course the Finns often seem to have "unknown objects" wandering about their waters.

The British and the French managed a collision a few years back and there are stories, sometimes published as part of someone's obituary, about some scary close encounters in the past.

No-one talks about today of course but you can bet it's going on 24/7

And the Royal Navy presumably still has shares in plywood and black paint so they can pretend it didn't happen - and I don't mean Ambush, Astute, Vanguard, Superb or Trafalgar.

It is something it has Talent for but then that wasn't the first time either.

Have you considered that might be the next logical step for you? In progression of interests and hobbies. :}

Ordered on Kindle just now.
The Secret State was good - so looking forward to this.

Knew I had this filed away somewhere. From October, 1968;

https://cimg9.ibsrv.net/gimg/pprune....5a6521fb54.jpg

Recounted in reasonable detail from p311 in my copy of "The Silent Deep"

(For clarity, that's the HMS Warspite incident)

HMS Sceptre also had a close encounter with an iceberg (aka K-211) that required the use of the battleshort to sort the situation out.

I would imagine one reason is you would want your vessels operating in or near their wartime areas, thus if the poo did hit the fan and rapidly escalate literally in days, the boat would be where it was needed, not having to fast track there. Hence you wouldn’t want to announce your position.

Hennessy is brilliant, a historian of modern times, using modern language and a tinge of humour.
A very few days into the Chinese Plague he was interviewed by the Beeb. He said [I summarise badly] that history would be seen for many years as BC and AC ...... before Covid, and After it struck. He basically said this is the big one, the global consequences will be severe and are unknowable.

And here we are, 2 years in, with "crises" not just here but [ill-reported] just about everywhere: supply chains, shortages, civil disobedience, balances of power upset, .....

A brilliant man, the pre-eminent historian of modern Britain.

"..... the 20,000,000 nuclear submarine Warspite...." Looks like the creators of HMS Vigil must have learned from that.....:ugh:

Jack

I think a '£' is missing from the front of that number.

A lot of RN submarines hit 'ice' over the years. 'Ice' often had a Russian accent.

An interesting one of late
Navy officers deny a submarine sank the fishing boat 17 years ago (msn.com)

Funnily enough I was watching an old episode of Kavanaugh QC the other day and the story was about a trawler lost with her crew. The owner and other locals started a conspiracy theory that there had been a collision with a submarine, but he had sent a non seaworthy boat to sea and sabotaged her for the insurance money.. I was reminded of the tragic loss of the Fishing Vessel Pescado.

As for submarines in deep water, see - Why Billion Dollar Nuclear Submarines Still Run Into Things Underwater.

In February this year a surfacing Japanese submarine in home waters hit the hull of a Chinese container ship right above.
Take your pick of the various news source interpretations from factual to derisory.
https://www.google.co.jp/search?q=su...&client=safari

Seamount
 

https://www.thedrive.com/the-war-zon...j0kOzVUw7vYm5s


https://cimg2.ibsrv.net/gimg/pprune....19c335be8.jpeg

shades of the late Clive Cussler first novel


https://cimg3.ibsrv.net/gimg/pprune....efafa5a7b.jpeg

cheers