Talk:SpaceX reusable launch system development program/Archive 1: Difference between revisions
Content deleted Content added
m Archiving 1 discussion(s) from Talk:SpaceX reusable launch system development program) (bot |
m Archiving 1 discussion(s) from Talk:SpaceX reusable launch system development program) (bot |
||
| (4 intermediate revisions by 2 users not shown) | |||
Line 33:
::{{u|N2e}}, I'm always willing to help with images, where possible. The issue is that SpaceX is a private company and their Grasshopper testing has been done in-house, without NASA photogs present :D I've scoured available resources for free images of Grasshopper, and what's on Commons is what's available. F9-R is even more problematic since it is such a new program. To be honest, it is highly unlikely that any free images of the new landing system will be available until it actually comes into use, and it is entirely possible images won't be available even then. This is just a note about the realities of the situation, and I'll continue checking to see if resources come available. I'll also try reaching out to SpaceX public affairs to see if they would be willing to release ''something'' under a free license (they've done so in the past, but only for early F1 material, iirc). <span style="white-space:nowrap; text-shadow:gray 5px 3px 1px;">— [[User:Huntster|Huntster]] <small>([[User talk:Huntster|t]] [[Special:Emailuser/Huntster|@]] [[Special:Contributions/Huntster|c]])</small></span> 06:47, 24 November 2013 (UTC)
Just a suggestion for images, there might be some scope to put a Falcon 9 image in either the background and/or testing sections. --'''''[[User:WDGraham|<
:{{done}} — I took your suggestion and added an in-flight photo of the [[Falcon 9 Flight 6]] launch vehicle, just minutes before it did the first-ever retro-deceleration and controlled-descent flight test. So while we don't have any Wiki-license friendly pics of the test we can use, we can show the same rocket on the same day shortly before that flight test was run.
Line 58:
::::However, the Mach numbers are still listed first, which is contrary to what the B-class reviewer ([[User:WDGraham]]) suggested: that the SI units (km/h) go first, ahead of the Mach no. and mph numbers. I have asked for some help on changing the order. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 23:50, 4 December 2013 (UTC)
:::::If we drop the mph unit entirely, then the desired result is possible from the conversion templates: {{convert/sandboxlua|6|Mach|105000|km/s|1|disp=flip|sp=us}}. Keeping the mph output does not seem to work with this approach, unless the template itself is edited to put the metric unit before the customary unit in the default output. (At least, I can't figure out how to get the template to spit out two non-default conversions from one input!) The conversion template is in the middle of a massive re-write, and {{tl|convert/q}} is one of the gateways to the new version. (However, on further research {{tl|convert/sandboxlua}} might be more appropriate.) [[Special:Contributions/130.216.218.47|130.216.218.47]] ([[User talk:130.216.218.47|talk]]) 05:57, 5 December 2013 (UTC)
::::::I'd suggest retaining mph since it is probably of use to American readers - my suggestion would be x.x km/s (Mach y, zzzzzz mph). If the template doesn't currently support it, using static text could be an option. --'''''[[User:WDGraham|<
:::::::Thanks for the explicit guidance, WDGraham. I've done a little experimenting with {{tl|convert/q}} in my sandbox, and will try to get back to this article soon to fix it in the way you suggest: probably with a combination of {{tl|convert/q}} template conversion plus a "static text" option to get the mph handled too, since the template doesn't seem able to handle both km/s and mph along with the Mach no. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 18:15, 5 December 2013 (UTC)
::::::::I've gone ahead and changed these Mach numbers to plain text. While I love the Convert template, it cannot handle all situations, and it's better to be completely plain text rather than a mix of template and plain text. <span style="white-space:nowrap; text-shadow:gray 5px 3px 1px;">— [[User:Huntster|Huntster]] <small>([[User talk:Huntster|t]] [[Special:Emailuser/Huntster|@]] [[Special:Contributions/Huntster|c]])</small></span> 20:32, 5 December 2013 (UTC)
Line 64:
::::::::::Strongly disagree. I don't believe 1.8 km/s would be nearly as meaningful to readers as 6546 km/h. While "per second" is the official SI form, "per hour" is for use by BIPM. <span style="white-space:nowrap; text-shadow:gray 5px 3px 1px;">— [[User:Huntster|Huntster]] <small>([[User talk:Huntster|t]] [[Special:Emailuser/Huntster|@]] [[Special:Contributions/Huntster|c]])</small></span> 01:51, 6 December 2013 (UTC)
:::::::::::Two thoughts. 1) On the km/s vs. km/h, it appears that you (Huntster) and WDGraham have different views. I don't believe that needs to be resolved here as part of the B-Class review, so I'll stay agnostic on that, for now, and perhaps we'll discuss it further later on. 2) on the Mach conversions, I found one more use of the convert|Mach template in the article that was rendering badly; so I have replaced it with the identical manual conversion numbers you put in the lede. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 01:17, 9 December 2013 (UTC)
:::{{od|::::::::}} km/h first is better than Mach first, and I think that is sufficient for the B-class review. Moving forward, would it be possible to adopt a similar compromise to the one reached at [[International Space Station]], with km/s first but kph given as an alternative unit, or would that just result in there being too many different conversions? --'''''[[User:WDGraham|<
::*{{done}}—for purposes of this B-Class review, I believe that now both issues related to Mach nos.—the non-US spellings and the conversions for Mach nos., leading with SI units—are complete. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 01:17, 9 December 2013 (UTC)
Line 77:
::* ('''under discussion''')—see Talk page section below working on a new article name.—02:57, 28 November 2013 (UTC)
::*{{Inconclusive}}—The "Article name" discussion, below, reached "no consensus." I don't believe the "little bit odd" article title should preclude the completion of the B-Class review, unless you want to go further and say that it is more than a "little bit odd" and is an "unacceptable" title for a B-Class article. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 01:45, 9 December 2013 (UTC)
--'''''[[User:WDGraham|<
:::*Although there is no consensus on where to move the page to, I'd say there is a strong consensus that ''it should be moved''. I'm going to provisionally mark this a B-class, on the condition that this issue is resolved by the end of the year. --'''''[[User:WDGraham|<
:::::Thanks for the review! And I agree with you on the move: all three who weighed in were in agreement that a move was necessary; they just didn't come together on one of the early suggestions. I'll try to get back here when I have more time to see if we can't get more editors involved for a second time around. A bit too busy to do it today.[[User:N2e|N2e]] ([[User talk:N2e|talk]]) 02:35, 10 December 2013 (UTC)
::::::Move has been completed, per the consensus developed below, so I believe that completes any concerns you had in your provisional pass at B-class review. Please let me know if you have any other concerns. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 16:46, 17 December 2013 (UTC)
Line 110:
:::But the end result is still a rocket that is reusable. If you include ground systems in this mix, even current tech is (mostly) reusable. The rocket is what matters here, in my mind. <span style="white-space:nowrap; text-shadow:gray 5px 3px 1px;">— [[User:Huntster|Huntster]] <small>([[User talk:Huntster|t]] [[Special:Emailuser/Huntster|@]] [[Special:Contributions/Huntster|c]])</small></span> 16:16, 25 November 2013 (UTC)
:Of the four options suggested above my preferences would be #1 or #2. The third option is too wordy and in any case the end result of the programme will hopefully be a reusable rocket rather than just technology which might lead to one. I'm not sure about the scope on #4 either; this article will cover the development of the rocket but I would expect a separate article will be created when it actually starts flying. --'''''[[User:WDGraham|<
::Thinking about it a bit more, I much prefer #2, principally because it avoids the impression of the development of a single rocket. This development program is building a set of technologies that will be used as new piece parts of the booster of two existing rockets ([[Falcon 9]] and [[Falcon Heavy]]), and will be worked in in later years into one or more rocket second stages. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 04:23, 26 November 2013 (UTC)
Line 153:
::Maybe this is what you were talking about Huntster, but mach is a relative term. Mach 1 at sea level is not the same as mach 1 at 10km above sea level. So how exactly do we convert those units into SI when we don't have at the very least altitudes to work with?
::On the other points N2e brought up, I'll agree with both suggestions. Rounding to two significant figures would be fine, and km/s is probably better, even though it's less likely to be understood by a casual non-technical reader. If they want they can click on a wikilink and see what it means. — [[User:Gopher65|Gopher65]]<sub><small>[[User_talk:Gopher65|<
:::This is exactly what I was referring to Gopher...we'd need a source which gives the altitudes of first stage sep to properly convert the Mach figures. The Mach 10 sep figures for existing F9 rockets shouldn't be difficult to find, but I don't know that the Mach 6 altitudes are going to be available. If we can't find these altitude figures, it will be entirely inappropriate to provide conversions, as they will simply be wrong. I still do feel catering to the casual reader is important, though; I think most will know that "km/s" is kilometers per second, but I'm not sure that it will be nearly as meaningful as kilometers per hour...simply clicking a link isn't going to increase innate understanding of the figures. <span style="white-space:nowrap; text-shadow:gray 5px 3px 1px;">— [[User:Huntster|Huntster]] <small>([[User talk:Huntster|t]] [[Special:Emailuser/Huntster|@]] [[Special:Contributions/Huntster|c]])</small></span> 01:25, 30 December 2013 (UTC)
::::Huntster, good point about the altitude. I'll offer two comments. 1) however much we need the altitude as the article is today, with four significant digits in the conversion, we need worry about it a ''bit'' less when we are going only for two-significant digits in the converted numbers. 2) an easy way out, which solves the significant digit issue AND the less-than-certain altitude problem, is to use either an "approximately x.y km/s" or perhaps could provide a range of speeds that would cover the estimated altitude range. Either way, I don't think we should go with leaving only a Mach no. in an encyclopedia article for a general readership. Cheers. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 01:55, 30 December 2013 (UTC)
:::As I understand it, you're proposing that we switch to only mach numbers, because you don't have the altitude at which those mach values are correct. If you don't know the altitude then what use are the mach numbers anyway? It's just an arbitrary figure. --'''''[[User:WDGraham|<
::::It's an interesting point. The mach numbers really are fairly meaningless here ''except'' that it gives readers an idea that there is a significant speed difference for first stage sep between F9 and F9R. <span style="white-space:nowrap; text-shadow:gray 5px 3px 1px;">— [[User:Huntster|Huntster]] <small>([[User talk:Huntster|t]] [[Special:Emailuser/Huntster|@]] [[Special:Contributions/Huntster|c]])</small></span> 12:07, 30 December 2013 (UTC)
Line 328:
::I agree that the wording is poor and should be changed (it isn't almost impossible, it's "merely" difficult. Heh. Merely.). However, that bit about the "3% of the mass of the rocket" is quite true. In most 2 stage rockets, like the Falcon 9, it's more like a little less than 2%. Some particularly well designed, highly efficient, low safety margin, 3 stage rockets can hit 4%. It doesn't go much higher than that. Chemical fuel just isn't energetic enough for better numbers.
::The issue is that adding reuseability to a rocket is estimated to reduce payload to orbit by a bit more than 2 percentage points. For most 2 stage rockets that would mean the extra mass would be enough to stop them from obtaining orbit (less than 2% - more than 2% = nothing making it to orbit). Or, as Musk put it, they have a "negative payload to orbit". The 3% given in the article is just an averaging of the industry standard 2-4% figure. It should be replaced by "2 to 4 percent" IMO. SSTO vehicles face similar problems, by the way. The added weight reduces their payload to orbit to negative numbers. — [[User:Gopher65|Gopher65]]<sub><small>[[User_talk:Gopher65|<
:::Not all of it is true. It's true that payload fractions are only a few percentage points, but that can be overcome by using multiple stages. Whether that is economical is another question, but there is no doubt that it is physically possible. Whether (reusable) single stage to orbit is possible is not certain. Some believe it is, others are skeptical. Two stage to orbit is generally believed to be possible, and three stage to orbit should be no problem. [[User:Mmeijeri|Martijn Meijering]] ([[User talk:Mmeijeri|talk]]) 08:23, 2 August 2014 (UTC)
Line 540:
::Agree with [[User:JFG|JFG]]. This article is an encyclopedic description of the overall development program to achieve this significant advancement in human technology. Took years, broad vision, and the overall technology advancement here is much larger than any particular reusable launch system. This is about a set of ''multiple'' technologies--in engines; materials science; guidance, navigation and control; hypersonic ==> subsonic atmospheric flight controls; business; private incentives; competition; interdisciplanary systems development; etc.--being used on ''multiple'' reusable launch systems: Falcon 9, Falcon Heavy and the Interplanetary Transport System. Not even all of the technologies used/tried/engineered/iterated and experimented with even made it to the final system in use in F9 today, let alone what will be developed for the next-generation interplanetary launch vehicles and spacecraft.
:: Having said that, there may one day be room (or need) for an article on some particular current reusable launch system, that would not have all the encyclopedic breadth of this article. That's fine, when the need arises. But this article's scope would be misrepresented by re-titling it as proposed. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 19:53, 20 April 2017 (UTC)
== External links modified ==
Hello fellow Wikipedians,
I have just modified 3 external links on [[SpaceX reusable launch system development program]]. Please take a moment to review [https://en.wikipedia.org/w/index.php?diff=prev&oldid=780011123 my edit]. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit [[User:Cyberpower678/FaQs#InternetArchiveBot|this simple FaQ]] for additional information. I made the following changes:
*Added archive https://web.archive.org/web/20131207085028/http://www.faa.gov/about/office_org/headquarters_offices/ast/environmental/nepa_docs/review/documents_progress/spacex_texas_launch_site_environmental_impact_statement/media/SpaceX_Texas_Launch_Site_Draft_EIS_V1.pdf to http://1.usa.gov/YtxBzo
*Added archive https://web.archive.org/web/20140322013556/http://archived.thespaceshow.com/shows/2212-BWB-2014-03-21.mp3 to http://archived.thespaceshow.com/shows/2212-BWB-2014-03-21.mp3
*Added archive https://web.archive.org/web/20140322013556/http://archived.thespaceshow.com/shows/2212-BWB-2014-03-21.mp3 to http://archived.thespaceshow.com/shows/2212-BWB-2014-03-21.mp3
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
{{sourcecheck|checked=false|needhelp=}}
Cheers.—[[User:InternetArchiveBot|'''<span style="color:darkgrey;font-family:monospace">InternetArchiveBot</span>''']] <span style="color:green;font-family:Rockwell">([[User talk:InternetArchiveBot|Report bug]])</span> 11:38, 12 May 2017 (UTC)
== "Starship hopper"? ==
There is a section heading in the article now entitled "Starship hopper." Do we have a source where SpaceX is calling the first test article "Starship hopper"? If not, is is a widely used name such that it might be sort of a "common name" for it?
I've seen the name used somewhere... but I've also seen media calling it the "BFR dev ship", a "hopper", the "BFH", the "BFWT" (water tank, 'cause that's what it was thought to be as build began in Dec 2018 in what later became the Boca Chica Spaceshipyard), etc. Descriptively, and not trying to use any one particular cute name, it is simply just the ''Starship test flight rocket.'' . In other words, not sure Wikipedia should be using something that isn't a common name, nor a name SpaceX is calling it. Cheers. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 01:39, 29 January 2019 (UTC)
== Second stage as spaceship ==
The "Second-stage reuse" section of the article currently states an, "integrated second-stage-with-spaceship design [...] has not been commonly used in previous launch vehicles." But see [[RM-81 Agena]]. The final launch was in 1987; 365 were flown. Does that flight history somehow fail to qualify Agena as having been "commonly used?" ([[User:Sdsds|sdsds]] - ''[[User talk:Sdsds|talk]]'') 06:15, 22 May 2018 (UTC)
:Just saw this question [[User:Sdsds|sdsds]]. Is a good one. I had time only to skim that Wikipedia article prose, but not go after the sources. Do you think there is a good source anywhere that does a solid job explicating just how the Agena might be thought to have been an "integrated second-stage-with-spaceship design"? Otherwise, it seems a bit like Agena, and maybe even a few of the Chinese second stages being used today, are more "integrated second-stage-with-attached satellite" designs. But even that might be worth mentioning to improve this article if we could find sources that are descriptive of some sort of integrated-second-stage designs in contrast to the BFR design integrated reusable spaceship designs. Cheers. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 14:20, 8 November 2018 (UTC)
::Ah, thanks [[User:N2e|N2e]] your thinking on this is good. Musk (the cited source) pretty clearly knows "spaceship" can refer to both a human-carrying and a satellite- or probe-carrying vehicle, but he might mean us in this context to be thinking of human-carrying vehicles where (to my knowledge) nothing quite like what's envisioned for BFS was ever "commonly used." (Or ever used at all?)
::I'm sure there are sources we could cite describing Agena (and the others you mention) as being integrated second-stage and payload vehicles but in the context of Musk's assertion, mentioning that what he said might be misconstrued would probably be out of place! ([[User:Sdsds|sdsds]] - ''[[User talk:Sdsds|talk]]'') 02:20, 31 August 2019 (UTC)
== Recent edits ==
I reverted the recent [[WP:BOLD|Bold]] and [[WP:AGF|good faith]] edits that added a detailed numeric list of all the many years of test flights to this [[WP:GA]] good article. Let's [[WP:BRD|discuss]] it on first and see if ther is a consensus for this change.
This article describes a long-term multi-year program of technology development for many different launch and spacecraft systems at SpaceX, and describes the development of fundamental rocket technology that Musk has said SpaceX will have failed if they don't eventually get there: fully and rapidly reusable rockets. I don't believe it will be helpful to have yet another article with a detailed count of every test flight and success/failure/who knows. Rather, this article can reference those other articles that maintain detailed counts by the particular vehicle. [[User:N2e|N2e]] ([[User talk:N2e|talk]]) 12:18, 30 August 2019 (UTC)
:You also reverted several other good changes. You also added back information that is obviously outdated. Could you please only revert the part you object to and not just blindly revert everything because you object to half a sentence? There was no "detailed numeric list", there was a first and last flight. We also list the first and last flight for a couple of other vehicles in the article, I don't see what would be different for Starhopper. --[[User:Mfb|mfb]] ([[User talk:Mfb|talk]]) 03:12, 31 August 2019 (UTC)
| |||