British & French nuke sub collision

[localhost127]

caught this article from an obviously sketchy news source, but has anyone heard anything in regards to this event from any other reliable source or media outlet?

http://www.thesun.co.uk/sol/homepage/news/article2240543.ece

BRITISH and French nuclear submarines which collided deep under the Atlantic could have sunk or released deadly radioactivity, it emerged last night.

The Royal Navy’s HMS Vanguard and the French Navy’s Le Triomphant are both nuclear powered and were carrying nuke missiles.

Between them they had around 250 sailors on board.

A senior Navy source said: “The potential consequences are unthinkable. It’s very unlikely there would have been a nuclear explosion.

“But a radioactive leak was a possibility. Worse, we could have lost the crew and warheads. That would have been a national disaster.”

The collision is believed to have taken place on February 3 or 4, in mid-Atlantic. Both subs were submerged and on separate missions.
Row

As inquiries began, naval sources said it was a millions-to-one unlucky chance both subs were in the same patch of sea. Warships have sonar gear which locates submarines by sound waves.

But modern anti-sonar technology is so good it is possible neither boat “saw” the other.

A senior military source said: “The lines between London and Paris have been hot.”

The MoD insisted last night there had been no nuclear security breach. But this is the biggest embarrassment to the Navy since Iran captured 15 sailors in 2007. The naval source said: “Crashing a nuclear submarine is as serious as it gets.”

Vanguard is one of Britain’s four V-Class subs forming our Trident nuclear deterrent. Each is armed with 16 ballistic missiles.

She was last night towed into Faslane in Scotland, with dents and scrapes visible on her hull. Triomphant limped to Brest with extensive damage to her sonar dome.


Triomphant has a crew of 101. Vanguard weighs 16,000 tons, is 150 metres long and has a crew of 140.

The MoD said it did not comment on submarine operations.

cannot seem to find any other headlines out there besides one at the daily mail, which i'll obviously stay clear and refrain from posting for obvious reasons.

[AegisFC]

Until something gets reported from a more legitimate source I wouldn't believe it.

I did some searching and the only The Sun and Drudge are carrying it (and Drudge is only linking back to The Sun).

[Driller]

Sounds strange in this day and age for 2 subs to collide.

[Unicorn]

Sounds strange in this day and age for 2 subs to collide.

It's not common, but not impossible.

Modern nuclear submarines (particularly ballistic missile submarines) are designed for quiet operations (its one of the drivers of the increase in size of ballistic missile subs) and as such, they spend most of their time cruising at a slow speed, often running the reactor on natural convection to avoid using circulation pumps (a common source of noise).

I could imagine both boomers utiling the same patches of water, as the areas they look for are identical. That is low traffic areas, distant from any areas that might attract other peoples ASW assets, far from the shipping lanes and within SLBM range of your targets.

As both France and the UK probably have similar target lists, and their boomer ports are not too far apart, geographically speaking, their operating areas are probably somewhat similar.

So, if you have two very quiet ballistic submarines both resembling an acoustic hole in the water, who both find themselves trying to occupy the same piece of watery real estate, then you could have an accident.

Basically it would have come as a complete surprise and resulted in a lot of collective pants shitting on both boats.

The key thing is that if this story is true, both boats have made it home in one piece.

Unicorn

[dave_kiwi]

Until something gets reported from a more legitimate source I wouldn't believe it.

I did some searching and the only The Sun and Drudge are carrying it (and Drudge is only linking back to The Sun).

Well the story has turned up in the Sydney Morning Herald:

http://news.smh.com.au/breaking-news-world/nuclear-subs-crashed-in-atlantic-report-20090216-88s5.html

Not that it makes it any more "legit". See source is AFP. Did see an article some time in the last week saying that the "Le Triomphant" had limped back into port just recently - maybe Defence Talk, but cannot exactly remember where

[riksavage]

The 'Torygraph' has posted a report, which appears credible. Looks like the French SSBN came off worse, most likely due to the UK SSBN's greater mass and kinetic force on impact. Makes reference to high-seas, which one assumes is irrelevant if they were both submerged at the time.

Both Captain's no doubt attended 'interviews without coffee' and are now scanning available opportunities at their local labour exchange!

http://www.telegraph.co.uk/news/newstopics/politics/defence/4634582/British-and-French-nuclear-submarines-collide-in-Atlantic.html

[WillS]

Both Captain's no doubt attended 'interviews without coffee' and are now scanning available opportunities at the local labour exchange!

Or perhaps they'll get medals, after all the whole point of these subs and their deterrent value is that they are 'undetectable'. I remember reading that the RN regularly boasts that nobody has ever managed to detect one of their ballistic missile boats out on patrol.

Its not as if you can get someone to hang out of a porthole to use the Mk 1 Eyeball on a sub :-)

I love the way that the Telegraph story implies damage to the French boat was significantly more than that to Vanguard - in a sort of "my boat is bigger/better than your boat" kind of way. Old habits die hard.

WillS

[Lostfleet]

When I first heard the news, I thought it might be a collision between a US and Russian sub playing cat and dog on the north atlantic but it was a complete suprise to see a UK and a French boomers finding each other on the Atlantic.

A simple question to submariners here, for the two submarines to be at the same location is a coincidence, however is it a coincidence for them to be at the same depth?

From my basic knowledge I know you have to be below a certain line ( I forgot the name of the line) for quiter operation but is there a certain depth according to the salinity of the water and other properties that it is perfect for quiet operations?

[kev 99]

Shown on both BBC and ITV morning programmes this morning.

[windscorpion]

Glad no one seems to be hurt, from the scanty reports we have anyway.

I trust this will put paid to some suggestions i have read in some places that the RN might try and make do with just 3 boats in the replacement Vanguard class.

I suspect there may have to be better co-ordination between the 2 navies now!

[WillS]

I trust this will put paid to some suggestions i have read in some places that the RN might try and make do with just 3 boats in the replacement Vanguard class.

Actually I suspect it might strengthen the case. If Vanguard is out of service for a long period of time and the patrols continue uninterrupted, I can just see some grasping politician, looking to 'save' some defence money to pour into the welfare budget, suggesting that the RN doesn't actually *need* 4 boats.

WillS

[wtsimpson7]

How could these subs not detect each other by means of sonar? It just seems strange to me.

[citizen578]

http://www.defencemanagement.com/news_story.asp?id=8577

http://www.bbc.co.uk/go/homepage/d/int/news/world/1/-/news/1/hi/uk/7892294.stm

Le Triomphant took the brunt of the impact, with a crushed sonar dome. From the reports about Vanguard, it seems she has ''dents and scrapes'', rather than anything monumental.

This should not have happened. However, with the sonar signiture of modern SSBNs being miniscule, and the habit of using the same 'bastions', it was never going to be impossible. A one-in-a-billion chance, but hey... how many of you play the lottery?!

[Super Nimrod]

All systems have their limitations, as said above despite their size they are very quiet when stooging around. They don't ping because that defeats their stealthiness.

Oh well the RN can no longer claim that they have never been detected on patrol anymore. Interestingly though the French press initially reported that they thought they had hit a sunken container.

You could almost say that both sides were nearly defeated by the effectiveness of their own technology :unknown

[WillS]

How could these subs not detect each other by means of sonar? It just seems strange to me.

Active sonar wasn't being used because its make the subs too detectable. Lewis Page in the Register has a nice piece on the subject:

http://www.theregister.co.uk/2009/02/16/subs_crash/

I like the sub-heading "Expensive undetectable machines undetected - shock".

WillS

[StevoJH]

Oh well the RN can no longer claim that they have never been detected on patrol anymore. Interestingly though the French press initially reported that they thought they had hit a sunken container.


Yes they can, if anything this just proves how quiet they are. They obviously werent detected since the French ran straight into them. As for afterwards, special situation, especially if the french government thought they hit a container and not just the press (did they?)

[windscorpion]

So is there another RN boat out there maintaining the deterrent or are they going to maintain the deterrent from dockside for a bit? Vigilant is in overhaul i know.

[Grim901]

So is there another RN boat out there maintaining the deterrent or are they going to maintain the deterrent from dockside for a bit? Vigilant is in overhaul i know.

I think so, isn't one of the other 4 kept at readiness just in case of an accident so it can put to sea in the damaged boats place. If I remember that was one of the reasons given behind needing 4 subs.

That certainly seems to be the French system.

[KGB]

The French boat had damage to the sonar dome, located in the bow. No damage to the bow of the British boat was reported...

Doesn't that suggest that the Triomphant was trying to track the Vanguard? Almost every reported sub to sub collision occurred in the context of one sub closely tracking another. With quiet subs and their short detection ranges, the chance for collision goes up. The fact that "they were going very slowly" is of course meaningless, since that's what subs do when they want to be quiet.

http://www.armscontrol.ru/subs/collisions/db080693.htm

[kev 99]

SSBNs don't track each other, they were both on routine patrol and just happened to both be in the same place at the same time.

[OnYourSix]

Hi, I was hoping someone would be kind enough to help clear up an armchair admiral argument I'm having at the moment.

It started after reports of the 'bump' between the French and UK SSBN's were verified.

My ' friend ' was amazed that this could happen given the size of the operating area.

My counter was that the operating area wasn't as large as some might think, given that both boats are looking to achieve the same thing and would use missile range, geography,currents, thermals, avoidance of shipping lanes and fishing grounds, know Russian routes into the N. Altantic and other considerations when planning a patrol.

He is convinced I'm wrong as the D5 Trident has a range of over 11000km ( it's shorter when all 12 warheads are in place but START 2 reduced this to 4 I think and I've read that the UK only carry 3 warheads.) so these SSBN's could operate within most of the Altantic and be able to hit any target in Russia.

Does anyone know if this is the case or have a rough idea of their effective operating area?

Many thanks.

[Grim901]

Hi, I was hoping someone would be kind enough to help clear up an armchair admiral argument I'm having at the moment.

It started after reports of the 'bump' between the French and UK SSBN's were verified.

My ' friend ' was amazed that this could happen given the size of the operating area.

My counter was that the operating area wasn't as large as some might think, given that both boats are looking to achieve the same thing and would use missile range, geography,currents, thermals, avoidance of shipping lanes and fishing grounds, know Russian routes into the N. Altantic and other considerations when planning a patrol.

He is convinced I'm wrong as the D5 Trident has a range of over 11000km ( it's shorter when all 12 warheads are in place but START 2 reduced this to 4 I think and I've read that the UK only carry 3 warheads.) so these SSBN's could operate within most of the Altantic and be able to hit any target in Russia.

Does anyone know if this is the case or have a rough idea of their effective operating area?

Many thanks.

1. While the area used is not the whole Atlantic, actually a relatively small area, it is still pretty big odds against a collision.

2. Trident D5 does have a long range (about least 8000km with 8 warheads fitted), but of course, the further away you fire from, the more chance of detection. (note: the distance between Moscow and the mid Atlantic is between 4 - 5,000 km)

3. Trident D5's only have space for 8 warheads I thought but was limited to 4 by the SORT treaty, which actually doesn't apply to the UK (US/Russia treaty).

4. Side note: START II was about de-MIRVing land based ICBMs and again only applied to the US and Russia.

5. The main target is Moscow, as it is the only current nuclear threat to the UK but it is quite far west so is fairly easy to hit from the Atlantic, and no, Trident could not hit every part of Russia from anywhere in the Atlantic. Russia is over 5,000km wide at least and the Atlantic ocean is a few thousand wide too + Europe in between the 2.

6. I doubt anyone could give you a rough idea of the operating area, too many classified variables.

[KGB]

SSBNs don't track each other, they were both on routine patrol and just happened to both be in the same place at the same time.

No one did anything improper and it was all a remarkable coincidence? That's naturally what the governments would say. It's like saying that the dog ate your homework; it's not impossible but no one buys that excuse.

They're not supposed to track each other but what's to stop an aggressive commander from trying? Incentives: practice for the crew, bragging rights, perhaps even career advancement for tracking such an elusive target. Periscope shots of carriers and audio recordings of submarines are like the stuffed buffalo heads of big game hunters. There aren't many Russian boats for sub commanders to track anymore, and I imagine precious few opportunities for a SSBN commander to track anything given their mission profile. But hotdogging and taking risks for career advancement is not unheard of.

[Unicorn]

http://pix.motivatedphotos.com/2009/2/17/633704965676927570-hmsvanguard.jpg

[OnYourSix]

1. While the area used is not the whole Atlantic, actually a relatively small area, it is still pretty big odds against a collision.

2. Trident D5 does have a long range (about least 8000km with 8 warheads fitted), but of course, the further away you fire from, the more chance of detection. (note: the distance between Moscow and the mid Atlantic is between 4 - 5,000 km)

3. Trident D5's only have space for 8 warheads I thought but was limited to 4 by the SORT treaty, which actually doesn't apply to the UK (US/Russia treaty).

4. Side note: START II was about de-MIRVing land based ICBMs and again only applied to the US and Russia.

5. The main target is Moscow, as it is the only current nuclear threat to the UK but it is quite far west so is fairly easy to hit from the Atlantic, and no, Trident could not hit every part of Russia from anywhere in the Atlantic. Russia is over 5,000km wide at least and the Atlantic ocean is a few thousand wide too + Europe in between the 2.

6. I doubt anyone could give you a rough idea of the operating area, too many classified variables.

Thank you for your reply and putting me straight on a few facts.

[nevidimka]

http://www.spacewar.com/reports/Nuclear_subs_didnt_know_theyd_hit_each_other_999.h tml

http://www.spacewar.com/reports/French_navy_looking_at_damage_from_nuclear_sub_col lision_999.html


But the Ouest France newspaper reported Thursday that in addition to the sonar dome, Le Triomphant also suffered damage to its conning tower and sail planes, and that repairs would take some time.

Now I know the French hit the British sub head on towards the belly of the british sub because it damaged its sonar. But how does the French sub damage its Tower ans sail if that is the case? The tower and its sail are behind the nose at the top.

Also if the French sub suffered major damage and the British just scrapes, does it mean the french sub is built less stronger to its British counterpart? they are only 2000 tonnes displacement different.

Also from the report, while the French went back to their port due to the damage, the British sub continued with its patrols! :onfloorl:
When the news broke out, I thought both subs came up and then realised they have hit each other, not like this. :D

Btw I always like the look of the British Vanguard, with its peculiar horn shape for the sail section. Looks menacing out of the water, but has a ugly sonar dome and sail design. :) The french 1 looks typical though.

[FluffyThoughts]

I am surprised no-one has raised this before, so here goes....

Where were the escort SSNs? Surely one of the Trafalgars should have been on sentry with Vanguard...?

One hopeful ray-of-light for Her Majesty's Royal Navy: if no escort was available, then the argument that seven Astute subs are enough flies out-of-the-window. 'Ave-it, as some might say...! :p:

[Grim901]

http://www.spacewar.com/reports/Nuclear_subs_didnt_know_theyd_hit_each_other_999.h tml

http://www.spacewar.com/reports/French_navy_looking_at_damage_from_nuclear_sub_col lision_999.html


But the Ouest France newspaper reported Thursday that in addition to the sonar dome, Le Triomphant also suffered damage to its conning tower and sail planes, and that repairs would take some time.

Now I know the French hit the British sub head on towards the belly of the british sub because it damaged its sonar. But how does the French sub damage its Tower ans sail if that is the case? The tower and its sail are behind the nose at the top.

Also if the French sub suffered major damage and the British just scrapes, does it mean the french sub is built less stronger to its British counterpart? they are only 2000 tonnes displacement different.

Also from the report, while the French went back to their port due to the damage, the British sub continued with its patrols! :onfloorl:
When the news broke out, I thought both subs came up and then realised they have hit each other, not like this. :D

Btw I always like the look of the British Vanguard, with its peculiar horn shape for the sail section. Looks menacing out of the water, but has a ugly sonar dome and sail design. :) The french 1 looks typical though.

If something 2000 tonnes heavier than you hit you, you'd feel it. :cool:

The British sub is slightly newer and possibly more advanced than the French counterpart. Not sre about the French but at least some sections are British subs are hardened like American subs to break ice. It may also have had something to do with the nature of the collision, not an expert but aren't the sonar dome and sail more vulnerable and fragile?

@Fluffy: I hope they do realise 7 isn't enough, but this incident probably won't do it, politicians aren't very good at connecting dots. No mention of the escort though, must have been a little way off and unlikely to have seen the French either. They are on the look out for other Hunter killers, not other SSBN's.

[citizen578]

This is in danger of becoming a conspiracy theorists' merry-go-round.

A ~16000 tonne object does not stop in the instance something hits it, it's momentum would have caused damage beyond just the sonar dome. This is common sense.

Will we ever find out the full circumstances behind this? definitely not. I'm surprised the MoD even released a statement about it, very unusual.

Just get over it and stop speculating - it never ends.

[Uhu]

Now I know the French hit the British sub head on towards the belly of the british sub because it damaged its sonar. But how does the French sub damage its Tower ans sail if that is the case? The tower and its sail are behind the nose at the top.
This is actually what would happen to any submarine, doesn't matter wether it's a 500t Type 206 or a 45000t Typhoon: The collison forced the Le Triomphant down and the HMS Vanguard up and when the french sub passed below, it's sail struck HMS Vanguard's hull again.

Also if the French sub suffered major damage and the British just scrapes, does it mean the french sub is built less stronger to its British counterpart? they are only 2000 tonnes displacement different.

The sonar dome is the softest spot of any submarine. You might damage it with a strong kick I guess. The dome and sail of todays subs are outside the pressure hull and are pretty weak structures. The pressure hull on the other side is not. So the outcome would be exactly the same if it had happened with switched positions and courses.

I actually expect the interior damage of the HMS Vanguard to be greater than Le Triomphant ones, since subs are stiffer longitudinally than lateral. Maybe the British sub even have lost power (see below).


Also from the report, while the French went back to their port due to the damage, the British sub continued with its patrols!
HMS Vanguard did NOT continue its patrol. While all news agencies agree that Le Triomphant made it back on its own power, some wrote that HMS Vanguard had to be towed.

[ASFC]

HMS Vanguard did NOT continue its patrol. While all news agencies agree that Le Triomphant made it back on its own power, some wrote that HMS Vanguard had to be towed.

She wasn't towed home, she was helped up the clyde by her berthing tugs, which, incidently, happens with all Subs moving in and out of Faslane.

[Grim901]

She wasn't towed home, she was helped up the clyde by her berthing tugs, which, incidently, happens with all Subs moving in and out of Faslane.

You beat me to it. The rumour of being towed home came from the media and public's ignorance as to RN operating procedures.

I haen't seen a dae for when it arrived back in Faslane? Was it at the same time or later than Triomphant?

[Beatmaster]

Its acctually really a lucky thing ill guess, because in the middle of the ocean two sub collide thats has to be a one in a million thing.

Anyway if this is true or not, still think of the damage and risk lets say for a moment they would colide headon at flank speed than you will have 2 subs complete destroyed and probably a huge mushroom.

But one question really pops up, 2 ballistic subs both worth millions of dollars how is this possible that they can collide in the first place?
Because i assume for a moment that the onboard systems will alert the crew of close danger stealth or not there has to be at least a kinda sonar or any radiografic system that tells you that you are in very big trouble. ( Crashing into a sub seems to me a BIG problem)

Still sometimes a sub crashes a ship, a uncle of me is captain at a huge lifting vessel and he did have a crash a few years back with a sub that surfaced when he did run over it.
The damage on both ships was huge.

[Grim901]

Its acctually really a lucky thing ill guess, because in the middle of the ocean two sub collide thats has to be a one in a million thing.

Anyway if this is true or not, still think of the damage and risk lets say for a moment they would colide headon at flank speed than you will have 2 subs complete destroyed and probably a huge mushroom.

But one question really pops up, 2 ballistic subs both worth millions of dollars how is this possible that they can collide in the first place?
Because i assume for a moment that the onboard systems will alert the crew of close danger stealth or not there has to be at least a kinda sonar or any radiografic system that tells you that you are in very big trouble. ( Crashing into a sub seems to me a BIG problem)

Still sometimes a sub crashes a ship, a uncle of me is captain at a huge lifting vessel and he did have a crash a few years back with a sub that surfaced when he did run over it.
The damage on both ships was huge.

You need to read up through the posts in this thread and it'll answer how they collided. It's also unlikely for SSBNs to be doing things at flank speed.

I doubt there'd be a mushroom even if it did happen, the chance of the crash causing a nuclear explosion is almost impossible, a radioactive leak though is possible.

Usually when a sub and ship collide it's because someone wasn't paying attention. I read about an American sub a few years ago, the captain was showing off to some civvies, surfaced really quick and killed a bunch of Japanese kids on a tourist boat.

[nevidimka]

This is actually what would happen to any submarine, doesn't matter wether it's a 500t Type 206 or a 45000t Typhoon: The collison forced the Le Triomphant down and the HMS Vanguard up and when the french sub passed below, it's sail struck HMS Vanguard's hull again.

That was what I imagine happened when I was trying to make sense of it, but I discounted it because it would have been a massive collision, and the French sailors would have really felt like s**t in their bouncing sub. But again its surprising, that if the tower of the French sub hit the vanguard straight on, it would suggest a huge dent on the Vanguard.


The sonar dome is the softest spot of any submarine. You might damage it with a strong kick I guess. The dome and sail of todays subs are outside the pressure hull and are pretty weak structures. The pressure hull on the other side is not. So the outcome would be exactly the same if it had happened with switched positions and courses.

Is that true? different pressure strength for the Sonar and sail's. How does the sub then dive to crush depth? Wouldn't the Sonar section give way and the Sail's buckle?


1 more thing I'm curious of. They say they did not detect anything as they were going silent and both boats were stealthy, and that fine. But the moment they have that hugh impact, wouldn't the situation on both boats go haywire? Alarm ringing, people moving activity increasing? How come the sonar of both boats did not detect this heightened activity and realise another sub is there?

[Grim901]

That was what I imagine happened when I was trying to make sense of it, but I discounted it because it would have been a massive collision, and the French sailors would have really felt like s**t in their bouncing sub. But again its surprising, that if the tower of the French sub hit the vanguard straight on, it would suggest a huge dent on the Vanguard.



Is that true? different pressure strength for the Sonar and sail's. How does the sub then dive to crush depth? Wouldn't the Sonar section give way and the Sail's buckle?


1 more thing I'm curious of. They say they did not detect anything as they were going silent and both boats were stealthy, and that fine. But the moment they have that hugh impact, wouldn't the situation on both boats go haywire? Alarm ringing, people moving activity increasing? How come the sonar of both boats did not detect this heightened activity and realise another sub is there?

Remember the collision was very slow. To use an anology, think of two cars both reversing out of a parking space at the same time and scraping against each other, lots of superficial damage to soft areas and paintwork, but the drivers hardly get thrown out of their seats.

I'd also heard that the Sonar dome and sail were outside the main pressure hull and were weaker areas (mentioned in my above post). But I think that their pressure can be increased but it reduces sonar efficiency *not sure on that one though so don't take my word for it*.

If an SSBN becomes easy to detect when it goes "haywire" as you say, how the hell are they supposed to prepare to launch a nuke without being detected. Anyway to answer the question, the stuff that makes the sub quiet to sonar works for things inside the sub too, so sonar won't pick up much from inside either, you'd only get a bigger return if they decided to increase speed or fire missiles just in case - which as you will agree, is a completely ridiculous idea after a crash.

[localhost127]

That was what I imagine happened when I was
Is that true? different pressure strength for the Sonar and sail's. How does the sub then dive to crush depth? Wouldn't the Sonar section give way and the Sail's buckle?


1 more thing I'm curious of. They say they did not detect anything as they were going silent and both boats were stealthy, and that fine. But the moment they have that hugh impact, wouldn't the situation on both boats go haywire? Alarm ringing, people moving activity increasing? How come the sonar of both boats did not detect this heightened activity and realise another sub is there?

also interested in both of these questions if anyone can answer.

now, after things settle down and this matter appears to have actually happened, i have to ask ... why/how is it that the sun and the daily mail were the first to report of such an incident?

[Systems Adict]

Is that true? different pressure strength for the Sonar and sail's. How does the sub then dive to crush depth? Wouldn't the Sonar section give way and the Sail's buckle?

Yes...

The Sonar dome is outside the pressure hull of a sub. It's filled with sea water which is at the same pressure as that outside. It's usually made of a thinner material to allow sound waves to move through it, (as are the diving planes). If a sub went to crush depth & was crushed, the dome would be okay, but the pressure hull would buckle like an empty coke can being squished in your hand.


1 more thing I'm curious of. They say they did not detect anything as they were going silent and both boats were stealthy, and that fine. But the moment they have that hugh impact, wouldn't the situation on both boats go haywire? Alarm ringing, people moving activity increasing? How come the sonar of both boats did not detect this heightened activity and realise another sub is there?

After a bit of trawling the web & a few blogs we can confirm that the accident took place between the 3rd & 5th of Feb, in the Bay of Biscay...

http://www.dailymail.co.uk/news/worldnews/article-1146124/How-close-did-crash-submarines-packed-nuclear-missiles-come-disaster.html

From the info I've picked up, it would appear that the British sub was sat on the bottom, silent. The French boat was in the process of submerging when it hit what it initially though was "a submerged shipping container". Having been more badly damaged it surfaced to check out all systems & as a precautionary measure. During this time, both boats would have went to damage control stations, but being silent on the bottom, it would have been easier for the British sub to identify the French boat.

The news only broke on Monday the 16th of Feb, & at that time the local Scottish TV news crew shot film at the boats' home base of Faslane, with HMS Vanguard in the background. As it's possible that they would have changed out the crew, it would have been more beneficial for the Govt to break the story to the media, prior to it being passed by word of mouth from the crew.

Finally...

To clarify some comments in earlier posts...

ALL submarines (no matter their nationality), must by law, surface & remain that way, once they leave the exercise areas South of the Isle of Arran, prior to entering the Firth of Clyde, for thier transit to Faslane / Coulport. They are then accompanied by a Police launch & an RN tender / support ship (NOT TOWED !).

This follows an incident in the 1980's when an RN sub dragged a fishing trawler to the bottom, when it snagged its nets.

[Padfoot]

Yes...

The Sonar dome is outside the pressure hull of a sub. It's filled with sea water which is at the same pressure as that outside. It's usually made of a thinner material to allow sound waves to move through it, (as are the diving planes). If a sub went to crush depth & was crushed, the dome would be okay, but the pressure hull would buckle like an empty coke can being squished in your hand.




After a bit of trawling the web & a few blogs we can confirm that the accident took place between the 3rd & 5th of Feb, in the Bay of Biscay...

http://www.dailymail.co.uk/news/worldnews/article-1146124/How-close-did-crash-submarines-packed-nuclear-missiles-come-disaster.html

From the info I've picked up, it would appear that the British sub was sat on the bottom, silent. The French boat was in the process of submerging when it hit what it initially though was "a submerged shipping container". Having been more badly damaged it surfaced to check out all systems & as a precautionary measure. During this time, both boats would have went to damage control stations, but being silent on the bottom, it would have been easier for the British sub to identify the French boat.

The news only broke on Monday the 16th of Feb, & at that time the local Scottish TV news crew shot film at the boats' home base of Faslane, with HMS Vanguard in the background. As it's possible that they would have changed out the crew, it would have been more beneficial for the Govt to break the story to the media, prior to it being passed by word of mouth from the crew.

Finally...

To clarify some comments in earlier posts...

ALL submarines (no matter their nationality), must by law, surface & remain that way, once they leave the exercise areas South of the Isle of Arran, prior to entering the Firth of Clyde, for thier transit to Faslane / Coulport. They are then accompanied by a Police launch & an RN tender / support ship (NOT TOWED !).

This follows an incident in the 1980's when an RN sub dragged a fishing trawler to the bottom, when it snagged its nets.


It's possible that Vanguard did see the French boat, just never had time to get out of the way? Indeed, how could they avoid such a collision if they were just sitting there?

[nevidimka]

Yes...

The Sonar dome is outside the pressure hull of a sub. It's filled with sea water which is at the same pressure as that outside. It's usually made of a thinner material to allow sound waves to move through it, (as are the diving planes). If a sub went to crush depth & was crushed, the dome would be okay, but the pressure hull would buckle like an empty coke can being squished in your hand.

OK, based from what you say the sonar being designed to be in the same pressure as the outside, and the sail I believe doesn't have enough volume inside for it to be crushed. Can anyone else confirm this?


After a bit of trawling the web & a few blogs we can confirm that the accident took place between the 3rd & 5th of Feb, in the Bay of Biscay...

http://www.dailymail.co.uk/news/worldnews/article-1146124/How-close-did-crash-submarines-packed-nuclear-missiles-come-disaster.html

From the info I've picked up, it would appear that the British sub was sat on the bottom, silent. The French boat was in the process of submerging when it hit what it initially though was "a submerged shipping container". Having been more badly damaged it surfaced to check out all systems & as a precautionary measure. During this time, both boats would have went to damage control stations, but being silent on the bottom, it would have been easier for the British sub to identify the French boat.

The news only broke on Monday the 16th of Feb, & at that time the local Scottish TV news crew shot film at the boats' home base of Faslane, with HMS Vanguard in the background. As it's possible that they would have changed out the crew, it would have been more beneficial for the Govt to break the story to the media, prior to it being passed by word of mouth from the crew.

Again that doesn't make sense. How does the French sub damage its Sail and Tower which is on top of the sub if the Vanguard is below it? I wouldn't expect that it did a somersault or role maneuver? :)


And IF the Vanguard was indeed static and below the french sub, they would certainly know that something that just hit them from above must be another sub, not a container. Plus once the French sub sonar dome,tower and sail are damaged, I doubt that it could even move away from that spot in its stealthy mode as its smooth outer surface design just went away. For sure the Brits with their claims of having some of the best sonar in the world would be able to detect a sub in that condition.

I suspect at least 1 party in the accident is letting us know less than what they really know.
Perhaps the Brits or even the french kept quiet about their discovery on the spot because they thought they might have hit a Russian submarine? The brits only decided to come out in public when the French came out with their story. Had the French never revealed anything, the Brits wouldn't have said a word too.

[Grim901]

OK, based from what you say the sonar being designed to be in the same pressure as the outside, and the sail I believe doesn't have enough volume inside for it to be crushed. Can anyone else confirm this?



Again that doesn't make sense. How does the French sub damage its Sail and Tower which is on top of the sub if the Vanguard is below it? I wouldn't expect that it did a somersault or role maneuver? :)


And IF the Vanguard was indeed static and below the french sub, they would certainly know that something that just hit them from above must be another sub, not a container. Plus once the French sub sonar dome,tower and sail are damaged, I doubt that it could even move away from that spot in its stealthy mode as its smooth outer surface design just went away. For sure the Brits with their claims of having some of the best sonar in the world would be able to detect a sub in that condition.

I suspect at least 1 party in the accident is letting us know less than what they really know.
Perhaps the Brits or even the french kept quiet about their discovery on the spot because they thought they might have hit a Russian submarine? The brits only decided to come out in public when the French came out with their story. Had the French never revealed anything, the Brits wouldn't have said a word too.

The British never claimed to have hit a container, the French thought that, and the theory of Vanguard being on the bottom could fit that theory.

Not entirely sure about whether they detected them afterwards, and I doubt the British will say if they did. It is official policy not to talk about stuff regarding the SSBNs.

[citizen578]

As mentioned previously, we'll never find out the true circumstances of this event. Like 99.99% of things to do with subs (especially bombers), the details will remain locked in a safe for decades.

However, there is zero chance of Vanguard being sat on the bottom. Sat just above the bottom, stationary - possible but unlikely. Low speed cruising is what these subs are designed for, it is where they are navigationally the most safe (yes, we can all laugh at that given what's just happened), and most importantly it is the condition under which their sensors work best. If the boat is stationary, it will not be able to deploy it's towed-array, it's most sensitive sonar system.


ALL submarines (no matter their nationality), must by law, surface & remain that way, once they leave the exercise areas South of the Isle of Arran, prior to entering the Firth of Clyde, for thier transit to Faslane / Coulport.

That's a bit of a distortion, a foreign submarine must by law surface in another countries' territorial waters (12nm in most cases - the Yanks are famous for getting caught submerged in the Strait of Hormuz). It has nothing to do with the Isle of Arran. I've navigated up the Firth of Clyde multiple times, and can promise you that under most tidal conditions it's already on the cheeky side to navigate a V or even T boat past the shifting bars and other seabed features.

I can guarantee you that you have not been told 100% of the truth, you never will be. Subs have accidents far more often than you think, Govt's only ever release the information if they have no other option.
Second-guessing the operational procedures of bombers, and trying to visualise an event which only about 200 people will ever know the reality of will get you nowhere.

[Sea Toby]

You are correct, we will never know much about the silent service. The truth is the fact that when these ships travel very slowly, they are very quiet. So quiet, they don't hear one another even at close range, even on a collision course.

[Lofty_DBF]

OK, based from what you say the sonar being designed to be in the same pressure as the outside, and the sail I believe doesn't have enough volume inside for it to be crushed. Can anyone else confirm this?


The sonar windows on submarines are made from fiberglass you can not kick it and smash it the only thing you will smash it your foot.
After all it has to be able to survive anything the ocean can produce.
Under the casing is all free flood area (when the submarine submerges the area fills up with sea water so it is a exactly the same pressure as diving depth).
The sail or Fin area on a submarine is external to the pressure hull aswel is all free flood area.
It is generally fiberglass construction and is where the submarines periscopes and other masts are located.

[Beatmaster]

You need to read up through the posts in this thread and it'll answer how they collided. It's also unlikely for SSBNs to be doing things at flank speed.

I doubt there'd be a mushroom even if it did happen, the chance of the crash causing a nuclear explosion is almost impossible, a radioactive leak though is possible.

Usually when a sub and ship collide it's because someone wasn't paying attention. I read about an American sub a few years ago, the captain was showing off to some civvies, surfaced really quick and killed a bunch of Japanese kids on a tourist boat.

Yeah i did read up the post buddy about the flank speed thing i said "lets say for a moment they would colide headon at flank speed " so it was pure theoretical/cinical and yeah you are right about the mushroom it is almost impossible still the fact remains that the risks could be huge if 2 subs ram eachother.:onfloorl:

[Beatmaster]

Still sometimes a sub crashes a ship, a uncle of me is captain at a huge lifting vessel and he did have a crash a few years back with a sub that surfaced when he did run over it.
The damage on both ships was huge.

If my memory serves me correct the vessel of my uncle was called the: Fairmount expedition see link (http://www.fairmountmarine.nl/media/tn_Doop%20FM%20Expdetion.JPG)

As far i know the original vessel has been put at the harbor to be turned into scrap metal because the damage was to mutch to repair.

I talked to my uncle he is now captain for 25 years and he said that collisions or near collisions happen even on open water.
It also seems that crashes between naval and commercial vessels happen mutch more often then we all see on the news or read in the news paper.
Most of the times its a near collision or just a small kiss between ships.
He also said that most of the times collisions are handled secret and the problems are solved by "Back door" means specially when it involves warships.

[Marc 1]

Yeah i did read up the post buddy about the flank speed thing i said "lets say for a moment they would colide headon at flank speed " so it was pure theoretical/cinical and yeah you are right about the mushroom it is almost impossible still the fact remains that the risks could be huge if 2 subs ram eachother.:onfloorl:

I disagree that the risks of a nuclear explosion 'could be huge'. Nuclear warheads have been dropped from aircraft, crashed inside aircraft, survived fires, you name it. They do not go critical unless they are armed and the detonation sequence is initiated. Worst case scenario the reactor core would leak radioactivity for a while. Most likely would be that if the boats are so badly damaged that they could not surface after the collision, reactor would shut down and lie on the sea bed quietly rotting... It's happened before, that nuclear boats have been lost at sea, and unfortunately, it will happen again.

[Marc 1]

From my basic knowledge I know you have to be below a certain line ( I forgot the name of the line) for quiter operation but is there a certain depth according to the salinity of the water and other properties that it is perfect for quiet operations?

I think the word you are looking for is 'thermocline'?

[Beatmaster]

I disagree that the risks of a nuclear explosion 'could be huge'. Nuclear warheads have been dropped from aircraft, crashed inside aircraft, survived fires, you name it. They do not go critical unless they are armed and the detonation sequence is initiated. Worst case scenario the reactor core would leak radioactivity for a while. Most likely would be that if the boats are so badly damaged that they could not surface after the collision, reactor would shut down and lie on the sea bed quietly rotting... It's happened before, that nuclear boats have been lost at sea, and unfortunately, it will happen again.

Ok got it.....
But theoretic speaking what would be the wors case senario for a sub when they do collide?

Because i know first hand that if a sub get rammed that most of the times the damage will be huge.

[nevidimka]

I suspect, the British might have thought that they hit a Russian Submarine. So they left quietly from that place.

[Systems Adict]

I suspect, the British might have thought that they hit a Russian Submarine. So they left quietly from that place.

Ruskie sub ?

Pah !

How many ACTIVE vessels are the Russian navy fielding at the moment, including subs ??? (and by ACTIVE, I mean ships / boats that are out "on business", not ready to go (minus a crew), or tied up alongside).

Yes, it's a possibility that the subs (French & British) where in the area to "observe" the movements of the Russian carrier & it's support vessels , although the group was transiting further west, to sail around the Irish / UK coast, before they transited North (& given that i have just the tiniest bit of doubt in my comments, possibly even a single sub??), but that was a group of 4 ships (??).

Add that to the two other (x2) groups from Russia that are sailing (??), then maybe 12 vessels in total (including subs) are out of Russian national waters.

Another million to 1 chance that they would have hit each other, just like the 2 vessels this thread is discussing ??

Then again, if the Brits had hit a Russian sub & kept quiet about it, I think the Russian's would have sung out about it !

SA

[Marc 1]

Ok got it.....
But theoretic speaking what would be the wors case senario for a sub when they do collide?

Because i know first hand that if a sub get rammed that most of the times the damage will be huge.

You've been inside a sub that had been rammed?

I agree that the worst case scenario which would be for the reactor to go critical at the exact same time as all the MIRV warheads went off would make a bit of a dent in the ocean for a second or two...But as has been pointed out the odds of that are pretty damn slim.

There are plenty of worst case scenario's we could play - one of these bulk LNG tankers going up in the harbour of a major city would cause a blevi (spelling - don't know the acronym) that would be like a tac nuclear weapon going off, and tens or hundreds of thousands killed or injured but people don't run around panicking over that.

[localhost127]

I agree that the worst case scenario which would be for the reactor to go critical at the exact same time as all the MIRV warheads went off run around panicking over that.

pardon my lack of experience wrt fission reactors, but isn't the fuel in nuclear power-plants quite low yield (enrichment?); enough to be critical for continuous fission reaction, but not high-enough yield to sustain an explosion?

...or can someone inform me if LEU in a fission reactor (sustained reaction) could somehow create a nuclear explosion? i don't believe so, but open to the information.


edit: sorry about the tangent, but i know information on naval vessel reactors is quite non-existant, but could anyone provide any useful links on the subject, or whether land-based fission reactors (fuel-type, etc) are the same type/materials (enrichment grades) being used in naval based?

[Grim901]

pardon my lack of experience wrt fission reactors, but isn't the fuel in nuclear power-plants quite low yield (enrichment?); enough to be critical for continuous fission reaction, but not high-enough yield to sustain an explosion?

...or can someone inform me if LEU in a fission reactor (sustained reaction) could somehow create a nuclear explosion? i don't believe so, but open to the information.


edit: sorry about the tangent, but i know information on naval vessel reactors is quite non-existant, but could anyone provide any useful links on the subject, or whether land-based fission reactors (fuel-type, etc) are the same type/materials (enrichment grades) being used in naval based?

The Uranium used in Nuclear reactors is much less reactive. By that I mean that it is only about 5-7% Uranium-235 and the rest is mostly Uranium-238, which is useless in most reactors. However the main control mechanism to stop meltdown in the reactor is the control rods (boron). If they were entirely removed i'm unsure exactly what'd happen, it's never actually been done as far as i'm aware, but the chances are a meltdown would occur where the reactor, moderator and casing melt (happened at Chernobyl for a different reason) creating a kind of lava, and releasing the irradiated substances contained within the reactor. In the case of a nuclear subs reactor, e.g the PWR2, water is used as a coolant and moderator, and becomes highly irradiated, this would mix with the sea water if released and cause massive damage.

As to whether the reactor would explode is a different story, that'd depend on the amount and enrichment of uranium present and how the damage actually occurs, but I think it is highly unlikely for a modern design to do so in terms of a nuclear explosion.

[localhost127]

The Uranium used in Nuclear reactors is much less reactive. By that I mean that it is only about 5-7% Uranium-235 and the rest is mostly Uranium-238, which is useless in most reactors. However the main control mechanism to stop meltdown in the reactor is the control rods (boron). If they were entirely removed i'm unsure exactly what'd happen, it's never actually been done as far as i'm aware, but the chances are a meltdown would occur where the reactor, moderator and casing melt (happened at Chernobyl for a different reason) creating a kind of lava, and releasing the irradiated substances contained within the reactor. In the case of a nuclear subs reactor, e.g the PWR2, water is used as a coolant and moderator, and becomes highly irradiated, this would mix with the sea water if released and cause massive damage.

As to whether the reactor would explode is a different story, that'd depend on the amount and enrichment of uranium present and how the damage actually occurs, but I think it is highly unlikely for a modern design to do so in terms of a nuclear explosion.

those were my same thoughts, but was just looking for confirmation.

thanks,

[Beatmaster]

You've been inside a sub that had been rammed?

I agree that the worst case scenario which would be for the reactor to go critical at the exact same time as all the MIRV warheads went off would make a bit of a dent in the ocean for a second or two...But as has been pointed out the odds of that are pretty damn slim.

There are plenty of worst case scenario's we could play - one of these bulk LNG tankers going up in the harbour of a major city would cause a blevi (spelling - don't know the acronym) that would be like a tac nuclear weapon going off, and tens or hundreds of thousands killed or injured but people don't run around panicking over that.

No No No not in a sub but i have seen photo's from my uncle and have seen the damage my uncles ship is/was really huge on of the biggest lifting vessels ever build and the hull and left side of the bow got almost complete destroyed.
The huge impact and damage on both ships did cost no human lifes but the Fairmount expedition was to damaged, and they did sell it to a scrap metal company and the sub, did also sustain to mutch damage to repair but my uncle never found out what they did with it he only knows that the sub did have a really big crack and was making water because the hull of the Fairmount expedition did penetrate very deep into the sub before he actually did run over the sub.

Thats all i know about it, i could ask my uncle for photos's but i cannot promise that he will allow it.


Yeah lets hope a wors case senario never happens