Talk:Docklands Light Railway rolling stock

P86/P89 stock retirement reasons?

Can you tell me the P86/P89 retirement reasons? — Preceding unsigned comment added by Clrichey (talk • contribs) 23:49, 22 December 2021 (UTC)

@Clrichey: Contained in the article - P86 because they weren't fireproofed (and therefore couldn't go to Bank), P89 because they were unsuitable for the higher demand of the system (they had slow opening doors). Easier to replace them with a complete new fleet - the B90/B92/B2K trains. Please remember to sign your comments WP:SIG Turini2 (talk) 13:10, 23 December 2021 (UTC)

I was GEC-General Signal project engineer for the DLR technical systems 1985 - 1991. The P86 were built to the fire safety standards current for surface operation at the time. They were not capable of multiple-unit operation, but fully in line with the capacity required (1500 pax/dir/h) by the original specifications of the DLR. For the extension to Bank and the 8-fold increase in capacity required by the 1987 upgrade contract, vehicles capable of running as 2-unit trains were necessary. These also had to comply with the new fire safety standards for tunnel operations that came into force as a consequence of the King's Cross underground station fire. These standards were implemented in the P89 stock that was built by BREL under licence from and using components supplied by LHB. Retrofitting the P86 stock was carefully considered but found to be prohibitively expensive. The internal trims would have had to be completely renewed. Therefore, the P86 stock was confined to Tower Gateway services until such time as new stock could be obtained while P89 was used on the Bank extension. A further consideration leading to the withdrawal of P86 and P89 stock was the decision to convert the entire DLR to the high-capacity SELTRAC moving block signalling system.

The "B" builds of DLR stock have an evacuation ramp built into their ends, allowing their use in tunnels that do not have a side walkway at vehicle floor height. 2003:E9:F73D:8300:D9A3:288F:21A5:6DA8 (talk) 17:00, 12 May 2023 (UTC)

(fyi we can't use this information in the article as per Wikipedia:No original research) Turini2 (talk) 17:09, 12 May 2023 (UTC)

Dimensions

The dimensions, where sourced, are currently cited to an unreliable looking site that doesn't actually contain the technical information (at least currently). This FOI request includes a technical drawing of the B07 stock (see the last message in the chain, dated 27 April 2017; note the PDF didn't display in my browser but worked fine in an external reader) and it contains slight differences to this article - e.g. the floor height in the drawing is 1023mm vs 1.03m in the infobox. I'd just go through and correct it/update the sourcing, but I don't know how to cite that drawing? Thryduulf (talk) 22:55, 13 July 2022 (UTC)

Reason for failed verification?

@Horse Eye's Back can you give an explanation for how the book reference failed verification (Pearce, Alan; Hardy, Brian; Stannard, Colin (2000). Docklands Light Railway Official Handbook. Capital Transport Publishing. ISBN 1-85414-223-2.) Did it fail because you had a copy of the book and were not able to find the referenced information, or did it fail because you haven't looked at / can't find a copy? 10mmsocket (talk) 15:45, 10 April 2023 (UTC)

@Thryduulf: is actually the one who made the claim[1]. Horse Eye's Back (talk) 15:48, 10 April 2023 (UTC)

So did @Thryduulf read the book? If not then it should bel left to stand for now. 10mmsocket (talk) 15:54, 10 April 2023 (UTC)

It has been left to stand. Horse Eye's Back (talk) 15:56, 10 April 2023 (UTC)

By left to stand I mean the reference, i.e. it should not be marked as "failed verification". Sorry for the confusion. I'm saying the tag should be removed. 10mmsocket (talk) 16:03, 10 April 2023 (UTC)

Marking it as failed verification isn't removing it... It is being left to stand. Horse Eye's Back (talk) 16:12, 10 April 2023 (UTC)

@Horse Eye's Back I did not make the claim in the article and do not have that book (although iirc parts are available on Google Books preview). However, the claim I was mentioning (the P in P86 standing for Poplar) is not the claim that you have marked as failing verification. If you do not have access to a source you should not be marking it as failing verification. Thryduulf (talk) 16:01, 10 April 2023 (UTC)

Having just checked, there is not preview on Google Books but I have ordered a copy of the later edition. Delivery is estimated to take about a week. Thryduulf (talk) 16:04, 10 April 2023 (UTC)

I have removed the "failed verification" claim for now. Look forward to your findings, especially if it's a source that lets you add more references to the various DLR-related articles. 10mmsocket (talk) 16:09, 10 April 2023 (UTC)

Unless its been verified you can't remove that tag. I too look forward to seeing whether it can be verified. Horse Eye's Back (talk) 16:13, 10 April 2023 (UTC)

"the 'P' referring to Poplar depot, where they were maintained." You said "but nowhere have I ever been able to find a reliable source stating this." It is my understanding that a failed verification tag is placed following the source and not within the sourced text. Also note that it was actually you who added[2] that text to the current article back in 2006, but when you added it there was no source given Horse Eye's Back (talk) 16:17, 10 April 2023 (UTC)

I have both the 2000 and 198X editions of the book, will check when I get back home on Tuesday. Turini2 (talk) 16:25, 10 April 2023 (UTC)

Looking through the history I doubt its in there, the person who added the citation actually removed that line[3]! It was subsequently restored by @EdJogg: [4] with no indication that it actually was verified. Horse Eye's Back (talk) 16:26, 10 April 2023 (UTC)

I looked for sources for this in 2019 - see /Archive 1#P and B - and didn't find any then. Obviously the current source has been added to the citation since then and didn't check before making my comment on the other discussion. It seems I did originally add the claim to the article, but I hope you will forgive me for not remembering edits I made 17 years ago or for not applying 2023 standards to 2006 edits.

None of this changes however that you marked as failed verification a claim that was sourced to a book you do not have, based on a statement someone else made (and which you did not attempt to verify) about a different claim in the same article. Thryduulf (talk) 16:28, 10 April 2023 (UTC)

The edit history doesn't lie. It was never properly sourced. The current source was added in 2009, not since 2019. Horse Eye's Back (talk) 16:30, 10 April 2023 (UTC)

I don't understand your point. I have never claimed it was properly sourced, only that I didn't find a source in 2019. You still have not explained though why you marked as failed verification a claim entirely unrelated to any statements made by anybody in other discussions, which is sourced to a book you do not have access to. Thryduulf (talk) 16:37, 10 April 2023 (UTC)

The key here is it turns out never to have been sourced to that book in the first place, in fact the only person we know for certain had access to the book removed the claim! So CN turns out to in hindsight be the appropriate tag, but we didn't know that at the beginning of the discussion. Horse Eye's Back (talk) 16:40, 10 April 2023 (UTC)

Now you've determined that, how about explaining why you marked a completely different claim as failing verification? Thryduulf (talk) 16:44, 10 April 2023 (UTC)

I marked that claim. Horse Eye's Back (talk) 17:05, 10 April 2023 (UTC)

No you didn't. You marked the claims about unit P11 as failing verification (ambiguously all of them or just specifically the the ones related to operating the first revenue-earning service on the DLR and being the first to move in Essen. Thryduulf (talk) 18:31, 10 April 2023 (UTC)

Yes that is how the tag works, its ambiguity has been raised before but consensus is that the ambiguity is appropriate. Would you have preferred that I remove the text entirely? That is the other policy approved solution, should I do it now? Horse Eye's Back (talk) 18:32, 10 April 2023 (UTC)

No, I would have preferred you to place the tag adjacent only to citations that actually have failed verification. Even if you had placed the correct "citation needed" template, you should place it adjacent to the claim that does need a citation. Thryduulf (talk) 18:44, 10 April 2023 (UTC)

And what does that have to do with the content of the article or improving the article in general? If you want to yell at me for perceived misconduct do so on my talk page or a relevant noticeboard, this is not the appropriate forum. Horse Eye's Back (talk) 18:54, 10 April 2023 (UTC)

Which statements have and have not failed verification is directly relevant to the content of the article, because a misplaced one actively misleads readers into believing that something correct is incorrect and, in some circumstances, that something (potentially) incorrect has been verified as correct. Thryduulf (talk) 20:12, 10 April 2023 (UTC)

We are not currently discussing whether or not a statement does or does not fail verification. We settled that issue long ago, there was in fact no source even though a lack of a tag (which you already apologized for) mislead readers into thinking there was. Horse Eye's Back (talk) 00:33, 11 April 2023 (UTC)

When I made that comment in 2019 the article looked did not include a source for the statement:.

The fleet for the 1987 opening consisted of 11 light rail vehicles (LRVs) built in 1986 by Linke-Hofmann-Busch in Germany and numbered 01 to 11. These were referred to as P86 stock, the 'P' referring to Poplar depot, where they were maintained.

The source at that time was clearly being used to verify the number of vehicles, their builder, the unit numbers and their designation. Thryduulf (talk) 16:43, 10 April 2023 (UTC)

So why was a CN tag not added to text which was known to be uncited? Horse Eye's Back (talk) 17:06, 10 April 2023 (UTC)

Regardless of whether a CN tag was placed at the time - the failed verification tag is also not the appropriate one in this case if you don't have the book in question / have proof that the book doesn't mention that information! Turini2 (talk) 17:40, 10 April 2023 (UTC)

Yes, but you can't know that unless you go all the way back to 2009 in the edit history. As it stood it appeared to fail verification, it only doesn't on the technicality that it was never sourced in the first place. Horse Eye's Back (talk) 18:02, 10 April 2023 (UTC)

My guess is that I didn't tag it as citation needed immediately because I was actively attempting to source it (which is always the best course of action) and simply didn't return to it at the time. Thryduulf (talk) 18:25, 10 April 2023 (UTC)

That sounds very reasonable. Looks like the current state of affairs satisfies everyone so unless anyone wishes to raise a new content issue I will bid y'all good day. Horse Eye's Back (talk) 18:30, 10 April 2023 (UTC)

References

Gallery?

Having just removed an image from the gallery that was already used to illustrate the prose, I'm actually wondering what benefit the gallery itself is bringing to this article? What are we illustrating there that is both encyclopaedic and not illustrated elsewhere? Thryduulf (talk) 14:17, 11 September 2023 (UTC)

Agree with you - in terms of retaining the photos

• "P86 stock fitted with pantograph" is interesting but probably more relevant in a Manchester Metrolink article
• Probably don't need both Essen photos in the article - and replace one of them with one of the shots of B90/B92/B2K.
• the shot of the B09 is better than the B07 in the gallery
• Poplar depot shot better in the Poplar DLR depot

Turini2 (talk) 18:34, 11 September 2023 (UTC)

Source 30 timestamp wrong

Source 30 is linked in section "Problems experienced" for hunting issues. It has the wrong timestamp. The link to the external video contains a timestamp to second 600, but the hunting issue is mentioned starting from second 398 --> https://www.youtube.com/watch?v=LfQEyU75wNQ&t=398s 129.247.247.239 (talk) 11:19, 25 April 2024 (UTC)

 Fixed. Thank you. Thryduulf (talk) 11:55, 25 April 2024 (UTC)