Talk:Rolls-Royce Merlin/Archive 3

English or British icon?
The reference http://www.icons.org.uk/theicons/collection/spitfire/features/the-merlin-engine from the website "ICONS: a portrait of England" includes the Merlin engine in its "The Icons" collection. The folks behind the website are Jane Finnis (Director), Jon Pratty (Editor), Aline Tanner, Marian Cleary, Dawn Marshallsay, Tara Booth, Stuart Walton, Emily Sands, Peter Chrisp and Jane Utting. This is not exactly what you would call a "self-published" website, not at all a personal blog. In terms of being for us a reliable source it sits somewhere between a blog and a well known reportorial website.

However, the people at ICONS are writers selecting "icons" based on a perceived relation to England. They are not selecting icons based on their relation to the Allied war effort, the whole English speaking world, the former British Empire or even just the British United Kingdom of WWII. If the group of writers had included Scottish, Welsh and Cornish ones in addition to English they may well have said the Merlin was a "British icon". Who knows?

What we do know is that the Merlin was built in other places besides England. Glasgow, for instance.

I spent some time looking up the connection between the words "icon", "iconic", "exemplar", "symbolic" etc., the words "Merlin" and "engine", and either "British" or "English". What kept reoccurring in my Google Books search was that the Spitfire was named as iconic or symbolic of British air power in WWII, not the Merlin, and not just "English". "British" was better represented by more than 2:1 ratio. Rather than trying to stretch the one reference farther than it was intended, rather than trying to use logic to change "English" to "British", perhaps what's best here is that the whole battle about the engine being considered an icon be dropped. Binksternet (talk) 02:45, 27 December 2009 (UTC)


 * Not a Brit, so maybe unbiased ;p, I'd say the Merlin is less iconic than the Spit in any case, so removing "iconic" wouldn't trouble me. "Best-known UK a/c engine"? (Or is that a variation on the same headache...?)  TREKphiler   any time you're ready, Uhura  04:12, 27 December 2009 (UTC)


 * What worries me is the removal of verifiable text cited using an accepted reliable source with the thought 'not sure if this source is reliable', prompted by the action of an IP who had no part in bringing this article to Featured Article status to my knowledge. As Binksternet points out the staff of the questioned website are qualified academics and the site itself is sponsored by a successor to the UK government's Department of Culture, Media and Sport. Both the text and source were examined during the recent FAC review (link in the header), commented on and accepted. The wording is 'considered an English icon', this does not preclude it also being a British icon. If we look at other icons listed there (red telephone box, Monty Python, Doctor Who, Marmite etc.) they can all be considered British as well. I will look for a source that says it is a British icon as well just to keep everyone happy (although it seems excessive to me). I am English and British, am I more one than the other or am I both? As far as the Merlin goes I don't care either way, just using the Wikipedia guidelines that are set up for us to write articles in an accepted manner. Nimbus (Cumulus nimbus floats by)    08:24, 27 December 2009 (UTC)


 * Gary, "not sure if this source is reliable" was simply an afterthought - an asking of the question. You've answered it, whish is fine. My primary reason for removing it was to try top defuse the edit war, and spur discussion. It wasn't intended to be a permanent deletion. Of course the engine is a British icon, but that isn't what the source said. Having drive-by IPSs play havoc like this is par for the course for an FA article, but they can be a bit myopic. I'm not sure we really need a source for this - was that pre-FA review, or because of it? Oh well! - BilCat (talk) 08:39, 27 December 2009 (UTC)


 * The phrase and source was added by User:KerryO77 on 26 March 2009. I just changed the wording back to 'considered' (if you look through the history you can see it was originally like this and possibly my wording). A very good reason for keeping this phrase and reference in the lead is a verifiable measure of the engine's considerable notability, another core Wikipedia policy (I am not wikilinking these policies for your benefit Bill but for others who may come across this conversation and may not understand them). Without it we are left with 'one of the most successful aircraft engines of the World War II era' which would be uncited editor's POV, I worked very hard to remove any uncited POV from this article (there was a lot) and this may be one reason why it managed to pass FAC. I must state again that I do not claim any ownership of this article but I do feel a responsibility, as the FAC nominator, to maintain the high standard, lest it end up at FAR (not an option). As it says in this talk page header 'if you can update or improve it, please do so', I don't regard removing chunks of cited text for convenience as improving the article. Nimbus (Cumulus nimbus floats by)    09:09, 27 December 2009 (UTC)


 * I totally understand your consternation at its removal, but again, I was trying to defuse the immediate situation, as the IP was only inclined to edit war at that point. Perhaps you would have done it differntly, but that's how I thought it best to handle the situation. I will be sure to better explain myself next time in my edit summaries. -


 * Not a problem, I did see that you wanted to take it to the talk page, which the IP editor declined. I always bear in mind that an IP may well not understand how it works, and as we know many persist with their viewpoints even after the guidelines have been explained (which takes up valuable typing time). Nimbus (Cumulus nimbus floats by)    09:36, 27 December 2009 (UTC)

1650?
While I realize it's uncited, it's also elementary math: pi(r2)(stroke)(#cyl)=displacment, & that gives 1648.96ci... TREKphiler  any time you're ready, Uhura  23:20, 4 January 2010 (UTC)

brought about by wartime needs..?
"...brought about by wartime needs..." ? In 1933/5? What war was that? —Preceding unsigned comment added by 188.122.34.10 (talk) 12:08, 7 February 2010 (UTC)

Manchester
Trafford Park is in Stretford which is now part of the Metropolitan Borough of Trafford. While it is in what most people would call "Manchester", and is certainly in Greater Manchester and the Manchester conurbation, there is no need for us to be sloppy. Mr Stephen (talk) 09:47, 22 March 2010 (UTC)


 * Any sloppiness would be on the part of the authors of the references used who failed to mention the precise location of the factory. Nimbus (Cumulus nimbus floats by)    22:48, 22 March 2010 (UTC)

Disambiguation
At Rolls-Royce Merlin, specific power is an unresolved link to a disambiguation page. Art LaPella (talk) 17:46, 26 March 2010 (UTC)


 * Fixed, this was caused by a recent shuffle related to that article, we are looking at it in the engine task force as power density is unreferenced at the moment. Nimbus (Cumulus nimbus floats by)    18:49, 26 March 2010 (UTC)

Unit conversions
Is there some good reason not to use the convert template? Some of the conversions suffer from excess precision. Rees11 (talk) 01:26, 27 March 2010 (UTC)


 * Probably not now, versions of it broke the MOS and FAC requirement to spell out in full the prime unit followed by the converted unit in parentheses. Should not be used in the specification table as these are cited conversion figures. The treatment of the units in this article needs to be discussed at some stage as recent edits have changed them from the sources used. By all means remove any excess precision in the text, I am thoroughly familiar with the convention at MOS:CONVERSIONS, I believe another editor added figures and did not follow the guideline (noting that I must have missed it, amongst other things, on the run-up to FAC). Nimbus (Cumulus nimbus floats by)    22:44, 27 March 2010 (UTC)


 * I fixed a couple obvious ones, but am reluctant to touch the others because as you say the conversions could be from citations, and if they're not obviously wrong it's probably best to leave them. Rees11 (talk) 23:11, 27 March 2010 (UTC)


 * All of the changes made by Gene Nygaard, are uncited and have been changed from cited sources (I have no doubt they have been done in good faith). I have tried to explain this but it didn't seem to register. As I mentioned on the project page I'm pretty sure that pounds-force/sq.in refers to the physical force exerted by the likes of hydraulic cylinders etc and has little to do with pressures generated by a compressor/supercharger. Minorhistorian (talk) 23:18, 27 March 2010 (UTC)


 * Pounds per sq. inch (psi) is a basic unit of pressure and applies to any use of pressure (may need a prefix for large numbers). Inches of mercury, Pascals are some other similar units. -Fnlayson (talk) 23:26, 27 March 2010 (UTC)

"Unit Cost £2,000"???????????????
The unit cost of this engine is listed as £2,000. This number is laughably low. Even in 1940 money it would have been at least 5x that amount. —Preceding unsigned comment added by 68.54.223.46 (talk) 03:52, 27 March 2010 (UTC)


 * I can't check the source, but here is a web page that says the Packard version was $25,000 in 1941: . The exchange rate at the time was around $4, so that would be £6250. So maybe not 5x, but 2000 does seem low. Rees11 (talk) 17:18, 27 March 2010 (UTC)


 * I spent some time trying to ascertain the cost, I deduced myself that it would be around £6,000 as discussed here. This would fit with the cost of a 1930 Rolls-Royce R at £5,800. The cost of £2,000 for the engine and £350 for the propeller came from a reliable book source that another user found during the improvement of this article. I doubted it but under our policy of verifiability, not truth that's all we have at the moment. It would be nice to find another source to either back this figure up or provide a new one that seems more reasonable. Mass production of the engine would/should have lowered the unit cost so perhaps this figure is correct. Nimbus (Cumulus nimbus floats by)    20:00, 27 March 2010 (UTC)


 * Not sure if it helps but the $25000 cost of the V-1650 above is also quoted by the USAF Museum (possible the original source) http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=846 MilborneOne (talk) 22:49, 27 March 2010 (UTC)
 * This reference has £2000 in 1940 http://www.the-battle-of-britain.co.uk/machines/Spitcost.htm MilborneOne (talk) 22:54, 27 March 2010 (UTC)


 * Would love to use it but it's not the cited cost of a Merlin at that time. The cost is cited, the doubt is whether the figure is correct, it may well be. We are stuck with the WP:VERIFIABILITY policy (verifiability, not truth as it says on the first line). There are some more Merlin books out there that may have it in, I've scoured the pages of the ones that I have and I never found it mentioned, which is frustrating. Nimbus (Cumulus nimbus floats by)    22:59, 27 March 2010 (UTC)


 * It's still possible. War time economies are usually highly distorted due to various taxes and subsidies intended to increase war production. That could be the price the government paid for the engines, reflecting some other subsidy we're unaware of, like free or cheap materials or labor. I think it might be ok to put a "dubious" tag on the figure to encourage editors to look in to this. Rees11 (talk) 23:06, 27 March 2010 (UTC)


 * There is some discussion of costs here. (Search for Merlin.)  Mr Stephen (talk) 23:27, 27 March 2010 (UTC)

TREKphiler  any time you're ready, Uhura  06:28, 28 March 2010 (UTC) Or not. (Check the sources first... : 06:30, 28 March 2010 (UTC)

Been searching more and remembered that our Rolls-Royce Kestrel article had a cost, it is cited as £2,051 in 1934, the Kestrel being very similar to the Merlin. It adds some perspective at least. Nimbus (Cumulus nimbus floats by)    20:52, 28 March 2010 (UTC)

Congratulations
Congratulations to all of those involved in the concerted effort to get this article to FA status! It was great to see it there on login today. --TraceyR (talk) 10:40, 27 March 2010 (UTC)


 * Concur. I know several of those involved, and that they put in a lot of hard work on this project. And thanks to the many vandals for once again proving "benefits" of open editing. It's always fun to see people prove how stupid they can be when they think they are anonymous! ;) - BilCat (talk) 11:01, 27 March 2010 (UTC)

Congrats! Well done, it's a fantastic article! Algaean (talk) 15:23, 27 March 2010 (UTC) (Guapovia)


 * Thank you on behalf of all the editors that worked very hard on it during the months and weeks leading up to the Featured Article review. Nimbus (Cumulus nimbus floats by)    20:02, 27 March 2010 (UTC)


 * I'll toss my congrats in as well! Well done! Btw, it seems like it took awhile to make it to the front page from when it was promoted... the R seemed to beat it by a long shot! -SidewinderX (talk) 22:12, 27 March 2010 (UTC)


 * Thanks, no idea how that process works, did look at it once. I think you can ask to have an article appear on a date related to the article but I did not venture any further than that!! The R did pop up quickly, all good stuff anyway. Nimbus (Cumulus nimbus floats by)    22:19, 27 March 2010 (UTC)


 * Not so long ago this was a start-class article - amazing what happens when editors who are often thousands of miles apart can work together in unison. The wonders of the internet! Congrats to all. Minorhistorian (talk) 22:43, 27 March 2010 (UTC)

Can anybody tell me when was the production halted?
First of all I'm really sorry I had to edit this section as I wasn't able to start a new topic. Anyway, nowhere I could find when was the production of these engines halted, or is it still in production today? If yes, then which version etc.? —Preceding unsigned comment added by 59.164.218.23 (talk) 15:36, 27 March 2010 (UTC)


 * In Rolls-Royce Merlin, it says production ended in 1950. -Fnlayson (talk) 16:58, 27 March 2010 (UTC)


 * Concerned that this information was missing I checked, it has been in the lead section since August 2009, here's the diff: . There are companies overhauling Merlins but I could not find enough reliable material to use, will keep looking as it is a fact that companies are supporting the engine. Someone, somewhere will be the current 'Design Authority' in the UK (similar to Type Certificate holder in the US) for the Merlin. Not tracked this down yet either but I'm working on it. Nimbus (Cumulus nimbus floats by)    20:05, 28 March 2010 (UTC)

Waiting for the stage
I see "2-speed" was change to "2-stage". Is this right? I seem to recall the Merlin used both a 2-speed single stage & a 2-speed 2-stage blower. TREKphiler  any time you're ready, Uhura  12:02, 28 March 2010 (UTC)


 * Need a diff to find the entry that you are highlighting as there have been so many edits recently, this summary taken from the article is correct:


 * 1) Single-stage, single-speed gearbox: Merlin I to III, XII, 30, 40, and 50 series (1937–1942).
 * 2) Single-stage, two-speed gearbox: experimental Merlin X (1938), Merlin XX (1940–1945).
 * 3) Two-stage, two-speed gearbox with intercooler: mainly Merlin 60, 70, and 80 series (1942–1946).


 * Hope that helps. Nimbus (Cumulus nimbus floats by)    18:49, 28 March 2010 (UTC)


 * Looking at this & wondering if I'm wrong. From your summary, looks like somebody corrected something that wasn't actually a mistake. (Thanks for tabulating, BTW.)  TREKphiler   any time you're ready, Uhura  19:24, 28 March 2010 (UTC)


 * Merlin XX used a two-speed, single-stage supercharger so, as you say the edit was not needed. I have restored it to the original version. Good spot BTW. Nimbus (Cumulus nimbus floats by)    19:39, 28 March 2010 (UTC)
 * Thx. Just lucky, I guess. (Rather be lucky than good? ;p)  TREKphiler   any time you're ready, Uhura  20:09, 28 March 2010 (UTC)

Points
Two simple points. The sound of the Merlin engine was unmistakable and very re-assuring. In the section on the carburretor there is some description of a pitch down rotation causing fuel starvation. Perhaps it would be better in these days to finally admit that aircraft with early Merlins were unable to fly inverted. Thus slow or hesitation rolls were out of the question as were outside turns. Which was why the myth about never doing a victory roll over the airfield because you might exacerbate any damage of the aircraft incurred in combat was invented. The truth was that there was every chance the engine might stop and at low level there was room neither to get out nor any chance of restarting the engine. —Preceding unsigned comment added by Drg40 (talk • contribs) 11:14, 29 March 2010 (UTC)


 * Actually Merlin powered aircraft could fly inverted and there is plenty of footage of Spitfires, for example, doing so. Admittedly they couldn't fly inverted for long. The problem was that the sudden onset of negative-g, such as when the aircraft was suddenly bunted into a dive, threw the fuel away from the outlet nozzle in the float chamber, leaving an air pocket; at the same time the float would stop doing its job properly, so that very soon after the onset of no fuel, the chamber would be flooded with fuel because the float wasn't closing off the fuel inlet. The Merlin suddenly found that there was no fuel, then there was too much (ie:fuel rich - the ratio of petrol to air is too great, stopping the ignition process): *Cough!* - *Splutter!* no power... then, as equalibrium returned, *bang!* Very uncomfortable if trying to escape from an angry Messerschmitt, annoying when chasing one. To dive properly the aircraft had to be half-rolled inverted into the dive then slowly half-rolled back again while in the dive.


 * The trick to inverted flying was to roll slowly into position, thus avoiding sudden negative g. The problem with exuberant young pilots pulling victory rolls over airfields was that they would more than likely flip the aircraft too quickly; sudden onset of negative-g - *Cough!* - *Splutter* ...Minorhistorian (talk) 20:59, 29 March 2010 (UTC)

I completely accept that's exactly right, but you do reaffirm my point that the reasons for not doing victory rolls were not as the myth. Very like the business about carrots improving night vision, the myth is over but the memory lingers on! I'm not sure I buy into your remarks about film coverage, however, as so often the films are too short to be sure what the aircraft is doing or are of the wrong mark of the aircraft and hence probably the wrong engine. AIUI there are very few films taken in the early days of Merlin powered aircraft and many of those are from Luftwaffe gun cameras. This is one of the articles where the lack of an ability to include short films is sorely missed, or is it perhaps that the films are not available?80.58.205.35 (talk) 13:05, 30 March 2010 (UTC)


 * I guess there would be a combination of reasons for not allowing pilots to do victory rolls over an airfield; risk of engine dying at an inconvenient moment; possible damage to control cables etc.; misjudgement on the part of the pilot - Douglas Bader's crash comes to mind - particularly if the pilot is still running on adrenaline after combat, and the possibility of other aircraft/equipment etc. being wiped out. You could be right about film coverage - just thinking about footage I have seen of a Spitfire I flying inverted it was for about five seconds, and the Spitfire may have been fitted with the Schillings modification. Minorhistorian (talk) 23:25, 30 March 2010 (UTC)

The use of non-breaking spaces
At WP:NBSP the guideline tells us to use non-breaking spaces, the  code, between numbers and abbreviated units, such as typing out '400 mph' when we want to see 400 mph without a line break between '400' and 'mph'. We read that hard spaces are appropriate "in expressions in which figures and abbreviations (or symbols) are separated by a space". The guideline specifically does not recommend using non-breaking spaces between a number and a full, unabbreviated word: one does not need to use non-breaking spaces between, say, '10,000' and 'feet', or between '400' and 'miles per hour'. I consider the excessive use of non-breaking spaces to be poor editing—its presence in a featured article sets a bad precedent. Binksternet (talk) 17:53, 30 March 2010 (UTC)
 * Just to understand what you are saying: put a non-breaking space between 400 and ft, but not between 400 and feet? Mr Stephen (talk) 18:14, 30 March 2010 (UTC)


 * WP:ORDINAL seems to indicate a contradiction: * When both a figure and spelled-out named number are used in a quantity, it is useful to use a non-breaking space, as in  or   to prevent a line break from occurring between them. The article was thoroughly edited for nbsps before the FAC, no comment was made otherwise. Perhaps the MOSNUM guideline talk page should be visited for clarification and this article can return to a relatively peaceful existence. Cheers Nimbus  (Cumulus nimbus floats by)    18:24, 30 March 2010 (UTC)


 * Join in the discussion I started at Wikipedia_talk:Manual_of_Style_(dates_and_numbers). See you there! Binksternet (talk) 21:38, 30 March 2010 (UTC)


 * There does appear to be a problem, are we the first to spot it? Way too many rules in there, apart from the fact that they change daily. When they have decided on the way forward we can apply it to this article which does have many numbers and units. Nimbus (Cumulus nimbus floats by)    22:17, 30 March 2010 (UTC)