Talk:HMS Astute (S119)

Launch?

I know the MoD and BAe say she was 'launched', but she never actually touched the water, did she? I was under the impression that she was wheeled out of DDH, Camilla threw some champers at her, and they wheeled her back in again. Is that wrong? Because if not, I think calling the ship 'launched' and using language like 'was built' is rather premature... Trent 900 15:08, 9 June 2007 (UTC)

Eugh. Camilla. But she's technically 'launched', just not yet in the water. They started the process of launching, but discovered it wouldn't work. 'Launched' is I think best for the interrim period. 172.189.193.156 02:13, 15 June 2007 (UTC)

I read in the BBC news that the HMS Astute four months ago, they discovered some problems on their second proto type model next the advanced Swedish submarines as the Swedish have who developed the most advanced subs next to the Russians. Even though the EMS is a beautiful sub, there are some problems that are too costly to fix. It is an probably an expensive turn over to manufacture these subs as British military budget has been cut by 42% in 2008 as the UK gov't has too much money in the banks and they have been behind on gov't payments. —Preceding unsigned comment added by 151.199.40.141 (talk) 03:47, 26 October 2008 (UTC)

There was a delay on the ship lift. She was finally lowered into the water on the 15th June.

Sonar Ability

I don't know a lot about sonar capabilities, but "Its sonar is so sensitive that it can detect and identify a ship setting sail from New York whilst in dock at Portsmouth" sounds way too good to be true. Where does this fact come from? DanielVonFange 13:22, 21 September 2007 (UTC)

Not only that, but it's too detailed for this article. This should be discussed at Astute class submarine as sonar capability is a class wide issue, not this boat-specific. Mark83 13:44, 21 September 2007 (UTC)

danielvonfange here's the link to the hear a ship set sail from new york edit

http://www.thisislondon.co.uk/news/article-23399926-details/Britain+launches+nuclear+sub+that+can+hear+a+ship+from+across+the+Atlantic/article.do

enjoy!

I have a fair bit of knowledge about sonar, primarily passive. Range is dependent upon ambient noise and the thermal structure of the ocean, among other factors. Trans Atlantic range? I strenuously doubt it.LorenzoB (talk) 23:26, 29 June 2008 (UTC)

Under ideal conditions in deep water but without thermocline, currents, plankton, sea traffic, bottom absorption etc - maybe (though it would be several times better than anything that has been built to date). But under real-world conditions? Hardly. NYC is a particularly bad example, as you'd probably need the target to be seaward of The Narrows to hear anything worthwhile over all the noise, no matter how sleek your tech is. "Honolulu to Chuuk" (about the same distance) would be somewhat more believable but the average UK news reader would scratch their head and ask themselves where Chuuk was.

I guess they simply took the theoretical maximum range under ideal conditions and measured off that distance on a globe.

In any case, the sonar suite is the new Thales 2076, which is supposedly (and I suppose that is correct) the most advanced sonar suite being built as of now. It has 10 times the processing power of "standard" top-notch sonar suites, but that does not translate into range 1:1.

The performance figures of the Thales 2076 are highly classified of course; the UK MoD apparently does not even want the US to get the system in their hands. But this MoD press release says, verbatim,

The advanced Sonar 2076 is a fully integrated system comprising bow, flank, fin and towed arrays that can track an object the size of a bus at a distance of more than 50 miles.

That is about 1.5% of what would be needed for a Portsmouth-NYC detection. And even considering that the data refers to a Trafalgar class SSN which is noisier, and even considering that most targets are far larger than a bus, and even assuming that the supposed transatlantic range would most likely be passive rather than active sonar (using active sonar at very long range will only get you killed) whereas assuming that the "track ... more than 50 miles" refers to active sonar (it it not easy to track anything with passive sonar alone at stand-off range), almost two orders of magnitude looks very much like science fiction.

(Though the Type 2076 might actually just be able to do the 50-mile trick passively; the combination of an extremely sensitive sensor array and the huge processing capability would place it into the realm of possibility given the bits and pieces of unclassified information available on sonar performances - a capable though not topnotch passive sonar of our time - say late Cold War designs - seems to be almost able to truly "track" small targets at a range of a few dozen km under good conditions. And this can indeed be much improved by throwing more processing power at it, the tracking bit (which is mostly probabilistic calculations) more than the detection bit (which is mostly filtering, and if the signal-noise ratio is too bad, more than in intermittent detection is essetnially impossible no matter how much processing power you throw at the problem).)

In a nutshell, as soon as the sciences are concerned, mass media are not to be considered an appropriate source for Wikipedia, unless proven otherwise (speaking from my personal experience in biology). Technically, the null hypothesis to falsify is "they suck as sources".

A simple workaround would be to scrap the "transatlantic" claim and cite the MoD release, with the note that the capabilities of the Astute are likely better due to the Astute class being quieter. Whether passive or active, the "50 miles" figure, though it might be a bit understated for reasons of national security, is a believable though rather nice performance under operational conditions in the open ocean.

Finally, as the USS Greeneville has proven times and again, a very capable (not topnotch but as a Type 688i fairly state of the art) sonar system is very much dependent on local and crew factors to perform as intended.

BTW S90 Torbay and subsequent Trafalgar class subs (S91, S92 and possibly S93) have (S90) or are slated to get (the others) the 2076 system too; any sub geeks here might want to update the pages. Source is the MoD release.

More tech data on the Astute class is to be found on naval-technology.com which, though essentially a huge digital sales brochure, is a very comprehensive and reliable source of primary data (equipment types/names etc). Dysmorodrepanis (talk) 01:46, 6 July 2008 (UTC)

Sonar [non-user plug]

see the press release: http://www.baesystems.com/Newsroom/NewsReleases/autoGen_1074119838.html it does claim "In the right conditions it can detect the QE2 leaving New York harbour from the English Channel.", while unlikely, thats the ships manufacturer talking. maybe miscommunication between BAE and Thales, who knows. Sorry i dont have the time to check the propper syntax for "talk" in wikipedia, hope this helps though feel free to edit this to your content —Preceding unsigned comment added by 81.106.142.62 (talk) 10:11, 9 September 2008 (UTC)

Nothing worse than some totally clueless sysop f/w jumping in and deleting content. —Preceding unsigned comment added by 81.158.99.211 (talk) 13:26, 16 November 2009 (UTC)

The press release is erroneous. Also please see above discussion regarding unrealistic statements regarding sonar capabilities 109.207.29.2 (talk) 08:13, 12 October 2012 (UTC)

Info on sea trial length

From The Telegraph:

"So finally in November 2009, Astute is starting 18 months of sea trials."

Gives an indication that whilst the boat may well be commissioned in 2010, it won't be in active service until 2011. David (talk) 18:23, 16 November 2009 (UTC)

Commissioning scheduled for 27/10/2010, which may change if she catches fire yet again. —Preceding unsigned comment added by 86.138.1.180 (talk) 19:02, 14 May 2010 (UTC)

Harpoon

The article claims that Astute will carry Sub-Harpoon, but there's no citiation and all sources that I can find seem to suggest that Tomahawk will be the only missile carried, in common with other RN SSNs.Jellyfish dave (talk) 17:40, 17 February 2010 (UTC)

I don't think you'll find any official sources talking about mines being carried either. 86.28.170.89 (talk) 00:01, 12 March 2010 (UTC)

Royal navy site describes Sub Harpoon as being deployed upon Swiftsure and Trafalgar class- it's reasonable to assume it'll be onthe astutue too. Meeware (talk) 17:07, 11 May 2010 (UTC)

'News in Brief' piece in The Times about Astute arriving at Faslane for first time, 21 Nov 2009:

"Astute will carry Harpoon anti-ship and Tomahawk cruise missiles, in addition to her 38 Spearfish torpedoes and mines"

Mark83 (talk) 16:20, 13 May 2010 (UTC)

Displacement

Some disagreement over displacement. Some sources say 7,200 tonnes, some 7,400, the following give 7,800 (submerged) – See Royal Navy: "When fully stored HMS Astute displaces 7800 tonnes of sea water (equivalent to 65 Blue Whales or nearly 1,000 Double Decker buses);" Defence Procurement Agency: "Dived displacement 7800 tonnes;" BAE Systems: "7800 tonnes submerged;" Defence iQ: "displacement of 7,800 tons submerged;" Naval Technology: "Displacement 7,800t (dived)." GwenChan 21:53, 22 October 2010 (UTC)

Above struck; see User talk:Ic451uk. GwenChan 22:34, 22 October 2010 (UTC)

Steam in footage of grounding

Does anyone know what all the steam from Astute is in all the news footage? I just think it would be a good addition to the article because it's not something normally seen from a nuclear sub. Mark83 (talk) 23:34, 22 October 2010 (UTC)

109 sundodgers brewing up? =) Joking aside, interesting question. GwenChan 23:41, 22 October 2010 (UTC)

I wondered that too. I have no inside knowledge, but from the photos and this diagram it seems to be emanating from the diesel exhaust - perhaps they shut down the reactor as a precaution, and were running on auxilliary power? Lynbarn (talk) 00:26, 23 October 2010 (UTC)

Agreed - if the submarine is grounded, there is a risk that the seawater cooling supplies to the reactor may be blocked (by mud, etc.), or the intakes may come out of the water. The reactor is therefore shut down as a precaution - but the submarine still needs power, so the backup diesel generators will be started. I suspect that efforts are made to cool the exhaust from these generators, both for safety and infra-red detection, and so the exhaust would therefore be visible as the steam (formed from the combustion of a hydrocarbon fuel) condenses to water vapour. Ic451uk (talk) 08:02, 23 October 2010 (UTC)

Although the plume of "steam" vented all day from Astute the Navy at Kyle claimed it was indeed the exhaust products of the back-up diesel generator. They must process the exhaust gasses somehow because as I watched the plume dissipated very quickly indeed exactly like steam and did not look at all like marine diesel exhaust. The main article is wrong about the location. Astute grounded less than a mile from the Skye Bridge. In fact she was just off the Kyleakin quarry less than half a mile from the bridge on a notorious rock plateau visible at low water. Fortunately she was not beached on this rock but grounded toward the quarry/bridge side. Astute was outside the navigable channel on the wrong side of the navigational warning buoy by some considerable margin. It is highly likely that her huge underwater mass was gripped by the extremely fast and powerful tide than funnels through the Kyles. Her low speed at the time of the incident probably exacerbated the tidal effect. She lay beached for the rest of the day and as the tide dropped nearly 50% of her top secret screw (propeller) was plainly on view. —Preceding unsigned comment added by 78.148.36.38 (talk) 20:19, 30 March 2011 (UTC)

Rumours of repair cost

I've reverted the edit that says "It rumoured that repairs will cost £8 million". I've done this because:

1. I don't think unsubstantiated rumours are suitable for the encyclopaedia
2. The reference quoted makes a number of other errors - in particular citing "the fatal crash of the FADEC controlled Chinook Mk2 helicopter on the Mull of Kintyre in June 2004" (it was 2 June 1994) and that Astute may be out of service until March 2011 (she sailed on 11 December - although not very successfully!)

Well-referenced sources for repair costs would be useful - but this is not a good source. Shem (talk) 15:47, 12 December 2010 (UTC)

Southampton Docks

The "Port of Southampton" extends to west of Cowes on the IoW, to south of Culver Cliff on the eastern shore of the IoW, and then north almost to the entrance to Chichester Harbour. A very large area as seen on this chart. So a vessel can be in the port of Southampton but not tied up at a berth, or even in Southampton Docks. The original picture caption was correct. Furthermore, the vessel's name is Her Majesty's Ship Astute, abbreviated to HMS Astute, not merely Astute. George.Hutchinson (talk) 13:59, 9 April 2011 (UTC)

George, the guidelines for the mentioning of specific vessels in ship articles is laid out in the Wikiproject ships manual of style. Regarding the use of HMS see here: 1

The key part is:

"Introductory sentence

The first sentence of (any) article should use the article title (set in bold face) early in the sentence and establish context. In the case of ships, set all elements of the name in bold face, with the ship's name also italicized; for example, HMS Ark Royal (R07), USS Enterprise (CV-6). "

and

"Later references to the same ship in the article should just use the ship's name, still in italics: Ark Royal or Enterprise." Antarctic-adventurer (talk) 19:01, 9 April 2011 (UTC)

Delivered - not "in service"

Shepherd media got the wrong end of the stick when Ambush and Astute were delivered yesterday. They have not finished sea trials, and they are not yet in service, but they have been delivered by BAE to the RN. The gov.uk article "Sixth Astute Class submarine keel laid" makes this distinction clear. The submarines will be declared "in service" when they are ready to deploy. Although submarines are a bit different in acceptance timelines, we had in similar confusion with the Type 45 commissioned/in service descriptions a few years ago. Shem (talk) 17:09, 19 July 2013 (UTC)