RMweb Premium jjb1970 Posted January 20, 2017 RMweb Premium Share Posted January 20, 2017 Warships have a whole suite of assurance tools, some of which go back over a century. Warships have utilised the concepts of redundancy, segregation of essential service and water tight subdivision for longer than anybody on this board has been alive (OK, I'm making an assumption there). Many of the requirements for design and construction are based on pretty ancient prescriptive rules. There are also some requirements for factors of safety of machinery and materials that are significantly more demanding than for commercial vessels. There are established rules for survivability standards, probably the best known of which is the concept of V lines. Warship systems are also designed and built to a defined shock rating. All of this stuff is old, well established bread and butter warship engineering. These tools have been augmented in recent decades by tools such as failure modes and effects analysis (FMEA), or you can add a C for criticality (FMECA), fault tree analysis, event tree analysis and all the other risk assessment tools of which I think all would be very familiar to railway engineers. Nowadays the biggest concern is the dependability of software controlled systems, including resilience to cyber attack (although experience tends to indicate that most cyber issues stem from uncontrolled patches, upgrades, use of peripherals etc than deliberate intent). Software assurance is massively expensive. In the case of the QEC, they've been designed and built to the Lloyd's Register naval ship rules which provide rules and regulations for design, construction and through life survey. These rules cover safety and reliability and provide rules for machinery, hull strength, electrical systems, propulsion arrangements etc. These are supported by a range of additional optional notations to enhance the basic rules requirements. These rules have pretty well replaced the old defstans and support the NATO standards. A key document is ANEP77 which is the naval ship code, basically like a military equivalent of SOLAS. In theory all of that should give you very robust controls to ensure the ship will be safe, reliable and resilient to damage. Unfortunately things don't always go as well as they should in the real world. 1 Link to post Share on other sites More sharing options...
Ohmisterporter Posted January 21, 2017 Author Share Posted January 21, 2017 Thanks for the reference to V lines, something I was unaware of. Having read up on Google I'm now feeling chuffed because I actually understood it! 1 Link to post Share on other sites More sharing options...
RMweb Premium jjb1970 Posted January 22, 2017 RMweb Premium Share Posted January 22, 2017 One erroneous assumption which is widely held on the question of warship assurance is that modern warships are built to commercial standards. This is based on the use of classification society rules, such as those of Lloyd's Register. The rules used for warships are naval specific rules. Although the requirements for certain equipment are pretty much the same as the commercial rules (and if they weren't, the MoD finally seem to be accepting that the diesel engines and GT's they buy are standard engines and not special.....) but have layers of additional integration and warship specific requirements. Some of the shaft line requirements are completely different and the hull and survivability rules are very different. Unfortunately the use of class rules got off to a very bad start with HMS Ocean, thanks to a combination of LR not really appreciating the very different operating environment of a warship and the MoD/RN not understanding what class approval means. However since then both parties have a much better understanding, the warship people get the benefit of a huge amount of technical expertise and development work they are no longer anything like capable of maintaining internally and class gets some good insights into certain technologies. 2 Link to post Share on other sites More sharing options...
Mike Storey Posted January 23, 2017 Share Posted January 23, 2017 The last few posts have been very re-assuring as regards naval engineering standards and failure risk assessments, thank you. How does this explain the problems being experienced with electrical overload on one type of our latest warships, when all the lights are turned on? (well, you know what I mean). It may well be that reports have been exaggerated, but they have not been denied AFAIK. How could something that basic have occurred in specification and acceptance? Any ideas? Link to post Share on other sites More sharing options...
RMweb Premium pete_mcfarlane Posted January 23, 2017 RMweb Premium Share Posted January 23, 2017 An interesting article about the supposed Trident test failure that the media and fringe politicians have been getting upset about over the weekend: https://ukdefencejournal.org.uk/serious-trident-missile-test-failure/ Their version is slightly different from the mainstream media's. 2 Link to post Share on other sites More sharing options...
RMweb Premium jjb1970 Posted January 24, 2017 RMweb Premium Share Posted January 24, 2017 The last few posts have been very re-assuring as regards naval engineering standards and failure risk assessments, thank you. How does this explain the problems being experienced with electrical overload on one type of our latest warships, when all the lights are turned on? (well, you know what I mean). It may well be that reports have been exaggerated, but they have not been denied AFAIK. How could something that basic have occurred in specification and acceptance? Any ideas? To really answer that you need to understand what is causing the loss of power and be familiar with the actual conditions on-board, apologies that is a statement of the obvious but there are so many potential causes and possible failures that could be at work that to offer any opinion is just speculation. As part of the approval process there will be an awful lot of type testing, the capability of the generators to respond to the most severe load changes has to be demonstrated (often using load banks which is hugely expensive), load balance calculations, harmonic studies etc all have to be completed. One potential cause is if the client has specified inappropriate ambient design limits for the power plant and associated cooling, ventilation etc. Another problem is increasing the load demand in service without really increasing generating capacity. Sometimes these major problems are caused by issues which seem laughably minor by comparison such as earthing of 12V instrument supplies. Sometimes finding the fault is a nightmare, one was losing power and after an awful lot of (expensive) investigation it was identified as simultaneous time dependent software faults on a triplex control system which the manufacturers assured us was impossible. And ultimately, people make mistakes. Any process is only as good as those carrying it out and in particular once certain parameters are agreed up front then there will be an error carried forward effect. 2 Link to post Share on other sites More sharing options...
RMweb Premium jjb1970 Posted January 24, 2017 RMweb Premium Share Posted January 24, 2017 An interesting article about the supposed Trident test failure that the media and fringe politicians have been getting upset about over the weekend: https://ukdefencejournal.org.uk/serious-trident-missile-test-failure/ Their version is slightly different from the mainstream media's. To be honest, if the Trident boats ever have to launch their missiles then one of them going off course and causing a mess where it shouldn't will probably be immaterial. If it ever gets to that then the world is pretty well done for. I think the media are turning a relatively minor issue into some much bigger than it deserves to be. Link to post Share on other sites More sharing options...
Ohmisterporter Posted January 24, 2017 Author Share Posted January 24, 2017 (edited) A bit more from Save the royal navy blog on the Trident missile test failure. http://www.savetheroyalnavy.org/why-we-should-have-every-confidence-in-the-trident-missile-system/ Edited January 24, 2017 by Ohmisterporter Link to post Share on other sites More sharing options...
RMweb Premium pete_mcfarlane Posted January 24, 2017 RMweb Premium Share Posted January 24, 2017 I'm slightly cynical about the supposed 'cover up'. It seems to be more a case of the MoD not putting out a press release detailing what exactly had happened. 1 Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted January 24, 2017 RMweb Gold Share Posted January 24, 2017 To really answer that you need to understand what is causing the loss of power and be familiar with the actual conditions on-board, apologies that is a statement of the obvious but there are so many potential causes and possible failures that could be at work that to offer any opinion is just speculation. As part of the approval process there will be an awful lot of type testing, the capability of the generators to respond to the most severe load changes has to be demonstrated (often using load banks which is hugely expensive), load balance calculations, harmonic studies etc all have to be completed. One potential cause is if the client has specified inappropriate ambient design limits for the power plant and associated cooling, ventilation etc. Another problem is increasing the load demand in service without really increasing generating capacity. Sometimes these major problems are caused by issues which seem laughably minor by comparison such as earthing of 12V instrument supplies. Sometimes finding the fault is a nightmare, one was losing power and after an awful lot of (expensive) investigation it was identified as simultaneous time dependent software faults on a triplex control system which the manufacturers assured us was impossible. And ultimately, people make mistakes. Any process is only as good as those carrying it out and in particular once certain parameters are agreed up front then there will be an error carried forward effect. According to various tales circulating among the lower deck several failures have occurred on occasions when all systems have been powered up - resulting in one occasion last year when one of the ships got no further out of Plymouth than the Western Approaches and returned under tow less than 48 hours after leaving port. Thus there seems to be the possibility - as has been publicly stated - that there is insufficient total power output end of; and that it might not be wholly related to operating in particular climatic conditions. Another story emanating from the fleet is that there are no manuals and fault tracing information for certain parts of the overall power equipment fit which is allegedly of US origin - but that of course might just be Jack engaging in his old habit of dripping when things aren't going well. 3 Link to post Share on other sites More sharing options...
Ohmisterporter Posted January 24, 2017 Author Share Posted January 24, 2017 (edited) I am also cynical about our "right" to know everything. Governments always have secrets, usually for good reasons, but parts of the media think that their chance to sell more newspapers or be the first with a sensational story takes precedence over everything else. As Terry Pratchett wrote, "The truth shall make you fret". I would rather not know, thank you. Edited January 24, 2017 by Ohmisterporter Link to post Share on other sites More sharing options...
RMweb Premium skipepsi Posted January 24, 2017 RMweb Premium Share Posted January 24, 2017 If they ever have to fire the missiles they have failed their task (deterrence) and the world will be going to hell quite quickly. Any missiles that don;t launch or fly to their target will be irrelevant anyway compared to other countries missile numbers. Link to post Share on other sites More sharing options...
trisonic Posted January 24, 2017 Share Posted January 24, 2017 Each Vanguard class submarine carries more firepower than the combined tonnage dropped by all the air forces in WW2 combined. It doesn’t take much to ruin someone else’s day. I like the completely British idea that each one carries a letter from the current PM - this covers contingencies such as he/she is killed before sending codes, How do they know when to use this letter? If both the World Service and R4 go off the air............. Best, Pete. 2 Link to post Share on other sites More sharing options...
alastairq Posted January 24, 2017 Share Posted January 24, 2017 If the report in the UK Defence Journal is even remotely accurate [which I am more likely to believe, than mainstream press?]....then the missile wasn't launched at the west African coast area, but at one of the US' ranges. [so, in accordance with press coverage, it wasn't 'off course'] It was destroyed [automatically?] because a fault was detected. [This would happen probably if fired in anger too?] It appears, UK Trident submarines don't operate using 'launch codes' from the UK Government.....but will only launch on consensus with the crew. [Relying on {superior??] discipline] It appears, the UK Tridents are entirely independent in operation, command & control, from the USA. [Only sharing repair & service facilities for the missiles, as a cost-saving measure] This is a 'bash-the-Government' issue, over something which, would ordinarily not be for public consumption. Why do we still buy newspapers??? For once, I sympathise with Government ministers over their exasperation at the ongoing vitriol......[OK, we lost the referendum, let's now cause trouble over any issue we can get hold of?} Link to post Share on other sites More sharing options...
Bon Accord Posted January 24, 2017 Share Posted January 24, 2017 If the report in the UK Defence Journal is even remotely accurate [which I am more likely to believe, than mainstream press?]....then the missile wasn't launched at the west African coast area, but at one of the US' ranges. [so, in accordance with press coverage, it wasn't 'off course'] It was destroyed [automatically?] because a fault was detected. [This would happen probably if fired in anger too?] It appears, UK Trident submarines don't operate using 'launch codes' from the UK Government.....but will only launch on consensus with the crew. [Relying on {superior??] discipline] It appears, the UK Tridents are entirely independent in operation, command & control, from the USA. [Only sharing repair & service facilities for the missiles, as a cost-saving measure] This is a 'bash-the-Government' issue, over something which, would ordinarily not be for public consumption. Why do we still buy newspapers??? For once, I sympathise with Government ministers over their exasperation at the ongoing vitriol......[OK, we lost the referendum, let's now cause trouble over any issue we can get hold of?} Trident is basically a US missile with a UK warhead which uses the US GPS system for primary navigation. As a secondary backup it has an onboard computer capable of taking celestial observations so as to plot a "fix" whilst hurtling along at Mach 24, this will hopefully make it possible for the missile to hit a target the size of London - maybe. Link to post Share on other sites More sharing options...
RMweb Premium jjb1970 Posted January 24, 2017 RMweb Premium Share Posted January 24, 2017 On T45, there has been a certain problem that demonstrates how critical it is to properly define certain operational parameters. Once they are agreed then everything that follows will be based on those parameters, if the ship goes outside those parameters then it does risk short circuiting the whole assurance process. Gas turbine power output is sensitive to ambient conditions, and the cooling and heating plant on-board is designed around assumed maximum and minimum sea water temperatures. Link to post Share on other sites More sharing options...
RMweb Premium pete_mcfarlane Posted January 24, 2017 RMweb Premium Share Posted January 24, 2017 (edited) It was destroyed [automatically?] because a fault was detected. [This would happen probably if fired in anger too?] It depends - it's highly likely that the missiles only send telemetry during test firings. I doubt if a real launch would advertise the position of the sub by broadcasting radio signals. It's also possible that the telemetry equipment is only installed in the missile for the test. If this is the case, then the failure is a total non-issue as it relates to a problem that can only happen in a test. Which is probably why the Government weren't that fussed about it. Edited January 24, 2017 by pete_mcfarlane Link to post Share on other sites More sharing options...
Ohmisterporter Posted January 25, 2017 Author Share Posted January 25, 2017 The Mail online has this story that could have had a really unhappy ending. http://www.dailymail.co.uk/news/article-4154464/Two-nuclear-subs-CRASHED-UK-coast-cold-war.html 1 Link to post Share on other sites More sharing options...
RMweb Premium jamie92208 Posted January 25, 2017 RMweb Premium Share Posted January 25, 2017 The Mail online has this story that could have had a really unhappy ending. http://www.dailymail.co.uk/news/article-4154464/Two-nuclear-subs-CRASHED-UK-coast-cold-war.html According to some reports that I've heard there were several encounters like that during the cold war at least one of which involved a British Sub. Jamie 1 Link to post Share on other sites More sharing options...
RMweb Premium pete_mcfarlane Posted January 25, 2017 RMweb Premium Share Posted January 25, 2017 The Mail online has this story that could have had a really unhappy ending. http://www.dailymail.co.uk/news/article-4154464/Two-nuclear-subs-CRASHED-UK-coast-cold-war.html I like the way the incident is described as happening off the coast of Argyll, and in the North Sea. Some slightly dodgy geography there by the Mail. Link to post Share on other sites More sharing options...
RMweb Premium jjb1970 Posted January 25, 2017 RMweb Premium Share Posted January 25, 2017 (edited) I think it now recognised that RN and USN cold war submarine operations, and those of the Soviet navy, were quite a bit warmer than the world would've been comfortable with at the time. Edited January 25, 2017 by jjb1970 Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted January 25, 2017 RMweb Gold Share Posted January 25, 2017 Ah well vengeance now seems to have moved on from a submarine to a ruling from the Supreme Court about something completely different and who caused it to be taken to that court in the first place. Yesterday's news would now be a wrapping for fish & chips if to do so was still legally permitted. Link to post Share on other sites More sharing options...
RMweb Premium Legend Posted January 25, 2017 RMweb Premium Share Posted January 25, 2017 (edited) The Mail online has this story that could have had a really unhappy ending. http://www.dailymail.co.uk/news/article-4154464/Two-nuclear-subs-CRASHED-UK-coast-cold-war.html Well I don't know , because I'm not party to state secrets but I highly doubt there was a collision off the Holy Loch. I've observed these submarines back in the day , I thought they submerged off the coast of Arran on their way out to sea,not directly off the Holy Loch as implied in the article and the map. You used to see them sailing down the Clyde , I've never seen one submerge at the Holy Loch , but of course I can't be certain. Nowadays you seldom see submarines on the Clyde even though all 4 Trident boats and the Astutes and Remaining T class boats are all now based in Faslane . Edited January 25, 2017 by Legend Link to post Share on other sites More sharing options...
Ohmisterporter Posted January 25, 2017 Author Share Posted January 25, 2017 There definitely was an underwater collision between British and French nuclear submarines. Link to post Share on other sites More sharing options...
RMweb Premium Legend Posted January 25, 2017 RMweb Premium Share Posted January 25, 2017 (edited) Oh yes I'm sure there have been a few collisions, I'm just questioning the fact it was directly off the Holy Loch . Extremely unlikely. I can imagine it may well have been around the Argyllshire Coast, off the Mull of Kintyre for instance. After all we used to send subs up to the Barents Sea to track their boomers as they came out of Murmansk., I'd imagine the Russians had a few sitting in the Irish Sea waiting to track ours. There have been reports over the last few years that Russian Subs have been waiting off the coast to intercept our Trident submarines. They used to be deterred by our Nimrod maritime patrol aircraft, but in a spectacular miscalculation, that really heads should roll for , we scrapped them in David Cameron's defence review, Thats certainly one of the reasons we are now having to invest in the US 737 derived Poseidon aircraft. Really what folly! Edited January 25, 2017 by Legend Link to post Share on other sites More sharing options...
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