Talk:SpaceX reusable launch system development program/Archive 1

Info

"F9R (pronounced F-niner)" --Craigboy (talk) 23:29, 2 May 2013 (UTC)[reply]

"I think we're a year away from being able to recover stages, then we'll take a look at them and extrapolate how many missions each stage can undergo. I hope to be reflying them a year after that. Rapid reusability, maybe another year. So in total, two to three years from now." - Gwynne Shotwell (June 2013)--Craigboy (talk) 04:19, 21 June 2013 (UTC)[reply]

"Essentially the v.1.1 and F 9-R are the same vehicle, although the upgraded F9 will not fly with the key reusable hardware – such as landing legs – until a later date."--Craigboy (talk) 05:39, 21 June 2013 (UTC)[reply]

Article improvement, with a purpose

With the recent progress in the development and test of this RLV technology, and the publically-announced plan that SpaceX is going to try for a test-flight return-and-vertical-landing of a Falcon 9 v1.1 booster stage, on Terra firma—while the second stage and payload continue on an operational orbital trajectory—as soon as February 2014, it is probably time to ramp up the effort on improving this article.

To that end, I intend to invite some serious copy-editing from a non-technical copy-editor from the Guild of Copy Editors, and perhaps from a technical (but non-space biased) copy-editor as well. Then I propose to ask a non-involved editor from WikiProject Spaceflight to evaluate the article against that project's B-class article quality criteria. Assuming it makes it through those reviews and interest remains, I believe it might be useful to strive to get the article to Good article status by the time of that first booster return test flight in early 2014. Rationale: if successful, that test flight will be an achievement in the History of technology, and will likely be of interest to a larger group of Wikipedia readers around the time of that flight.

I would very much welcome any other editors who might choose to pitch in and help. Cheers. N2e (talk) 21:19, 21 November 2013 (UTC)[reply]

B-class article review

A request for for a B-class article review was made on 24 November 2013 by N2e.
User:WDGraham did the review on 25 November 2013; see below.
Done—assessed as B-class on 9 Dec 2013 by WDGrham. N2e (talk) 17:37, 11 December 2013 (UTC)[reply]

Photo/image improvement

The article currently has only a single lonely photo, one of Steve Jurvetson's Flickr-stream photos of the early-Grasshopper v1.0 tank sitting on the test pad in a field in Texas: the photo is a very early shot, and was taken while the Grasshopper was not even yet completed. Moreover, the Grasshopper v1.0 is now retired, and the really important part of the eight GHv1.0 flights to date is the landing, not the mere sitting on a pad, nor the ascent or even rocket hover. It is that descent and landing aspect that has made each of the GH videos go viral on YouTube, and get wide coverage by the Space industry media, and what is the critical technology being developed by SpaceX to pull off the "rapid and full reusability" objective.

More importantly, the SpaceX reusable rocket launching system technology is so very much more than just Grasshopper, and really needs a few photos to illustrate different aspects of the technology development effort.

In order to get to good article status, any candidate article needs the images/photos to be brought up to a certain standard. I am not a photo/image savvy Wikipedia editor, and I am assuming that we will need to find one to help bring this article up to GA status by the end of January 2014.

SpaceX and media sites have released a LOT of photos of this technology, both Grasshopper and new F9-R landing legs, a couple of shots of the first booster return test flight in late-Sep 2013, etc. Anyone want to help, and figure out what we can do under what licensing authority to radically improve the photo game of this article N2e (talk) 05:19, 24 November 2013 (UTC)[reply]

I asked User:Huntster, whose wiki-image fu is strong, to take a look at the photo-related questions here. This is his response (originally published on his Talk page):

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). — Huntster (t @ c) 06:47, 24 November 2013 (UTC)[reply]

Just a suggestion for images, there might be some scope to put a Falcon 9 image in either the background and/or testing sections. --W. D. Graham 12:28, 5 December 2013 (UTC)[reply]

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.

Also added a contextual diagram of the Falcon rockets, so we could say to which two of them (F9 v1.1 and Falcon Heavy) the reusable technology is being developed for.

If anyone has an idea for how another good-license image might be used, please leave that suggestion here. N2e (talk) 17:56, 5 December 2013 (UTC)[reply]

Serious copyedit

With the B-class review and image search behind us... Next: plan to invite a serious copyedit from a non-technical copy-editor from the Guild of Copy Editors, and perhaps also from a technical (but non-space-biased) copy-editor as well. N2e (talk) 17:37, 11 December 2013 (UTC)[reply]

In progress—A request has been made to the Guild of Copy Editors. Full request is here. N2e (talk) 03:52, 23 December 2013 (UTC)[reply]

Done—by Baffle gab1978 (talk) 23:05, 7 February 2014 (UTC)[reply]

B class review

I have reviewed the article against the B-class criteria, and have found that it is very close to meeting the requirements, however there are a few minor issues which I think should be resolved before B-class status is conferred.

~~Referencing: Two very minor issues; reference #5 is currently a raw URL and needs to be formatted, and whether #39 is a reliable source is questionable - indeed another user has tagged it as such.~~

Done fixed by Huntster and N2e—02:57, 28 November 2013 (UTC)[reply]

Grammar/Style: Again, very minor. I noticed at least one point in the article where figures are given in non-SI values before SI values (speeds in the lead given in Mach) Kilometres per second would probably be the best SI unit to use here. I would also recommend changing all British spellings in the article to American ones.

(partially done) the non-US_English spellings were the result of the default output of the {{convert}} template; fixed by Chris the speller who was invited to come over here and have a look. The Mach/miles per hour/km per hour issue seems to be the result of the default output of the {convert|Mach} template; I have endeavored to fix it with the usual "<code>|disp=flip</code>" parm; but it seems to be broken and does not work as it normally does with the standard convert template. The velocities in the source document were given in terms of Mach number, and not either km/h or mph. N2e (talk) 03:38, 28 November 2013 (UTC)[reply]

A couple of editors have come along and made some changes to the Mach numbers and conversion template. The first (User:Glmory)cleaned up some odd errors from the convert/Mach use (errors I had not previously seen in the article), and another editor (IP 130.216.218.47 ) came along and used a somewhat different template, {{convert/q}}, to get the (previously broken) mph and km/h conversions added back to the article. This seemed to fix the errors, and keep conversions of the Mach numbers—which were the way the velocities are given in the source—to both km/h and mph.

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. N2e (talk) 23:50, 4 December 2013 (UTC)[reply]

If we drop the mph unit entirely, then the desired result is possible from the conversion templates: 1.8 kilometers per second (Mach 6). 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 {{convert/q}} is one of the gateways to the new version. (However, on further research {{convert/sandboxlua}} might be more appropriate.) 130.216.218.47 (talk) 05:57, 5 December 2013 (UTC)[reply]

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. --W. D. Graham 12:26, 5 December 2013 (UTC)[reply]

Thanks for the explicit guidance, WDGraham. I've done a little experimenting with {{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 {{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. N2e (talk) 18:15, 5 December 2013 (UTC)[reply]

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. — Huntster (t @ c) 20:32, 5 December 2013 (UTC)[reply]

Yeah, that works for me. The convert template is amazing, but it's not all things to all people. What did you think about WDG's suggestion of using km/s for the first SI velocity, then mph and Mach for the conversions? N2e (talk) 01:21, 6 December 2013 (UTC)[reply]

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. — Huntster (t @ c) 01:51, 6 December 2013 (UTC)[reply]

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. N2e (talk) 01:17, 9 December 2013 (UTC)[reply]

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? --W. D. Graham 14:37, 9 December 2013 (UTC)[reply]

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. N2e (talk) 01:17, 9 December 2013 (UTC)[reply]

~~The article could benefit from one or two more images, and ideally one in the top right corner of the page.~~

(under discussion) may not be possible to be easily fixed per Huntster comments in the above section (Talk:SpaceX_reusable_rocket_launching_system#Photo.2Fimage_improvement) .—02:57, 28 November 2013 (UTC)

Two additional images have been added to the article since the initial B-Class review was conducted last month. Neither is particularly representative of the entire technology program, but they do illustrate in part a single aspect of the technolgy program. The best images have not been released with wiki-appropriate licenses. N2e (talk) 01:39, 9 December 2013 (UTC)[reply]

So I conclude that it is:

Not possible, at the present time, per Huntster; perhaps can be improved Later

as more media is released that meets Wiki-image licensing guidelines, or perhaps we can later justify a "fair use" rationale of a single non-free image released by SpaceX. I don't believe that the absence of more/better images, or an iconic representative image of this entire technology program in the upper right corner of the article, should hold up the article passing a B-Level review, as even WP:GOODARTICLE standards do not require images in all situations. N2e (talk) 01:39, 9 December 2013 (UTC)[reply]

One other thing, the page title is a little bit odd - "rocket" and "launching system" are redundant to each other and it makes it sound as if it is a reusable system for launching rockets, rather than a reusable rocket development programme. Do you think a page move would be appropriate?

(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. N2e (talk) 01:45, 9 December 2013 (UTC)[reply]

--W. D. Graham 12:10, 25 November 2013 (UTC)[reply]

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. --W. D. Graham 14:37, 9 December 2013 (UTC)[reply]

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.N2e (talk) 02:35, 10 December 2013 (UTC)[reply]

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. N2e (talk) 16:46, 17 December 2013 (UTC)[reply]

Done—article name change was completed, per consensus, last week. See below. N2e (talk) 03:59, 23 December 2013 (UTC)[reply]

1) Ref #5 is handled...it no longer exists on the SpaceX site as far as I can tell, so I pulled from Archive.org. Performed lots of other citation fixes, including fixing a couple of URLs that were incorrect. I also agree that the forum cite should be removed...if a replacement cannot be located, the material needs to be excised. In my opinion, all the newspacewatch.com articles should be replaced since they've gone completely paywall (I'll be surprised if they survive), even though I've added archive links to all four of those cites.

2) I'll come back and clean up various conversion issues (definitely SI before non-SI in space-related articles), but I didn't immediately see much in the way of spelling issues. There's some formatting work to be done, but doesn't seem too bad.

3) As for images...they simply don't exist at this point in time (SpaceX is, after all, a private company, and conducts their testing in-house). I'm always keeping an eye out for them, but I don't expect anything until this version of the rocket is used for a NASA mission. However, lack of media should not disqualify the article from any status, even as Featured Article (I recall one last year that was passed without free media). Editors cannot be held responsible in situations like this.

4) I agree that "rocket" could be dropped from the title as redundant. Or, use something like "SpaceX reusable rocket program". Eh? — Huntster (t @ c) 14:09, 25 November 2013 (UTC)[reply]

5) Ref #39 is handled. I removed it for now, pending a reliable source, and opened a Talk page section on it below to let the editor who added that know why it was removed, and how it can get back in.

6) I believe that all of the non-US English issues are resolved. I asked editor Chris the speller to stop by and he helpfully found a way to make the {{convert}} template uses put the units in with US English spellings. N2e (talk) 02:57, 28 November 2013 (UTC)[reply]

Article name

The article name was, when the article was created in early-2013, SpaceX reusable rocket launching system, and has been to date (November 2013). The recent B class review (see above) suggested a name change may be in order as "rocket" and "launching system" are redundant, rather than a "reusable rocket development programme"

I concur with the reviewer, User:WDGraham. This article is about a fairly complex development program for multiple rockets and parts of rockets (first stages, second stages) using multiple engines (e.g., LOX/RP1, LOX/Methane) and other technologies (various control systems designs, multiple kinds/designs of landing gear), eventually full TPS for second stages, etc). Moreover, the program, as stated by the company and supported by sources, is occurring, and will continue to occur, over multiple years. (and when first named, I added this hidden text to the first sentence of the lede: "The '''SpaceX reusable rocket launching system''' is ...", knowing a name change would need to be accomplished later.)

Here are some ideas. I'm not sure of my own view yet on any one of them as being the most correct, so have not written this as a proposal for any one particular name. But I am personally partial to it being a "development program" rather than a "launching system" as I had originally named the article, as it is not some sort of single or comprehensive system at all.

SpaceX reusable rocket development program – mentioned by WDGraham in the B class review comment
SpaceX reusable launch system development program – seems rather descriptive; is it too long or cumbersome?
SpaceX reusable launch system technology development program – more cumbersome?
SpaceX reusable rocket program – mentioned by Hunster earlier today

If you have other ideas to kick around, please add them with bullets. Cheers. N2e (talk) 15:15, 25 November 2013 (UTC)[reply]

The first seems just fine, the second and third feel too wordy to me. No comment on the fourth :P — Huntster (t @ c) 15:20, 25 November 2013 (UTC)[reply]

Somehow "rocket" seems a bit on the narrow side to me. Since we call the rockets that do regular launches launch vehicles, and it seems that this is really more of a system, including ground systems, than merely a rocket. Clearly, SpaceX is developing a set of technologies to accomplish a large/complex goal: fully/rapidly reusable launch vehicles: a system. N2e (talk) 15:31, 25 November 2013 (UTC)[reply]

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. — Huntster (t @ c) 16:16, 25 November 2013 (UTC)[reply]

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. --W. D. Graham 18:41, 25 November 2013 (UTC)[reply]

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. N2e (talk) 04:23, 26 November 2013 (UTC)[reply]

How does #1 imply a single rocket? I certainly don't read it that way. Besides, it's rocket technology being developed, seems like it would be appropriate to use that word in the title. I'm not going to get worked up over the issue, though, so I'll step away for now. — Huntster (t @ c) 04:33, 26 November 2013 (UTC)[reply]

Well you might have partially answered the question: if we were to say, "rocket technology development program", that would not be so unclear. But to date, no one has suggested that particular name. While there seems to be no consensus on any name as of yet, my sense is the "rocket development program" implies the development of a single rocket, which seems an incorrect impression to leave our readers. On the other hand, "launch system development program" seems to better summarize/imply in a title that a set of technologies are involved in the "launch system", whereas "rocket" does not provide that impression. Cheers. N2e (talk) 01:51, 1 December 2013 (UTC)[reply]

Well, it's been a week and no one else has joined the discussion. The discussion above did not reach a consensus on a name change. I'm not formally "closing" the discussion, just noting the "no consensus" result. If someone else wants to propose an article name change, propose away, perhaps starting a new section below. Cheers. N2e (talk) 01:21, 9 December 2013 (UTC)[reply]

Well, don't take my opinion as anything other than that...an opinion. There's consensus that the title needs to change, and if #2 is acceptable to both of you, then I say go for it. — Huntster (t @ c) 06:00, 9 December 2013 (UTC)[reply]

Going once, going twice, ...

With the removal of an objection in the comment above by Huntster, it appears that we may have a consensus, since both other editors who weighed in (WDGraham and N2e) had indicated they would be okay with SpaceX reusable launch system development program, and all three editors have said that the current name needs to change.

Anyone else want to weigh in? If not, I'll move the article in about a week to SpaceX reusable launch system development program. N2e (talk) 17:43, 11 December 2013 (UTC)[reply]

Done, per consensus. N2e (talk) 16:42, 17 December 2013 (UTC)[reply]

9 engines or 3 engines in the Grasshopper v1.1 flight test vehicle?

A statement was recently added to the article that questioned whether Grasshopper v1.1 will have all 9 engines, as the current source in the article asserts, or perhaps only 3. The question is a good one, and the argument for only three is a strong one. However, we have no reliable source for the statement; so I have removed it for now. This is the statement removed:

There is some debate though on the question of whether on this first version of the upgraded Grasshopper if it will use all nine engines, since for testing only three engines will be used. This is supported by an image showing a Grasshopper in construction with slots for only three engines in an online image.<ref>{{cite web |url=http://thespaceport.us/forum/topic/38529-spacex-grasshopper-updates/?p=482632 |title=SpaceX Grasshopper (updates), post #204 |work=TheSpacePort.us forum |date=October 20, 2013}}{{full|date=November 2013}}</ref>{{verify credibility|date=November 2013}}

We can add it back when a reliable source is found, which will likely be in the next few months, to confirm either way. Cheers. N2e (talk) 02:42, 28 November 2013 (UTC)[reply]

Hypervelocity velocities given in Mach number in the source

As the article currently exists, several hypervelocity velocities that are given as Mach number in the source, have been converted to both SI-system km per unit time used in Category:Spaceflight articles, as well as mph for our less-metric-familiar readers of the encyclopedia. Example, from the lede, the current sentence shows those conversions this way:

"If the technology is used on a reusable Falcon 9 rocket, the first stage separation would occur at 6,546 km/h (4,067 mph; Mach 6) rather than the much faster 11,200 km/h (6,960 mph; Mach 10) for an expendable Falcon 9, in order to provide the residual fuel necessary to complete the deceleration and turnaround maneuver, as well as the controlled descent and landing."<ref name="pm20120207" />

There are two problems with this, and one of them (the first) probably has to get fixed before the GA review of this article after late-January.

The significant digits of the conversions (four digits) are ridiculously more than the one or two significant-digits of the source ("Mach 6" or "Mach 10"). At most, we should be rounding to two digits here.
There was a debate, above, about whether km/s or km/h was the most appropriate SI set of units in which to show the velocity. Of the two editors who weighed in with opinions, one went each way, and a third editor (me, N2e) stayed agnostic/neutral at the time. I'm going to take a position now and say that km/s is the more ordinary velocity metric for showing hypervelocity transitions under atmospheric conditions.

Would like to kick both of these problems around on the Talk page, and get this cleaned up in the next month prior to a GA-article review. N2e (talk) 04:50, 29 December 2013 (UTC)[reply]

Using only two significant figures isn't a problem, but I would like the figures double checked that they are correct with respect to altitude. Sources don't provide this info, and a cursory search didn't find anything. As for the SI argument, my concern is reader comprehension. Remember that our ultimate goal is for readers to fully understand what is written, and I'm concerned that using km/s isn't going to be nearly as meaningful as km/h. But again, this is just my opinion. — Huntster (t @ c) 11:13, 29 December 2013 (UTC)[reply]

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. — Gopher65_talk 16:20, 29 December 2013 (UTC)[reply]

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. — Huntster (t @ c) 01:25, 30 December 2013 (UTC)[reply]

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. N2e (talk) 01:55, 30 December 2013 (UTC)[reply]

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. --W. D. Graham 09:22, 30 December 2013 (UTC)[reply]

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. — Huntster (t @ c) 12:07, 30 December 2013 (UTC)[reply]

Yes, agreed. So why don't we just use the "approximately x.y km/s" {along with the Mach no. given in the source and the mph for American readers) locution, and avoid the problem of being overly altitude sensitive. Mach numbers are rough order-of-magnitude sort of numbers, at least when given with no decimal point in a general article discussing comparative staging velocities for a general-audience news source. N2e (talk) 13:40, 30 December 2013 (UTC)[reply]

I'm going to make a proposal, below. However, there was some concern over the need to confirm that the conversions we are using are correct, so I'm submitting the following to document that, and make our conversions explicit:

The conversions are based on the use of the {{convert/q}} template, which as far as I know, handles the numerical unit conversions quite well, but will not put the converted units in a form consistent with WP:WikiProject Spaceflight guidelines while doing so in a Good Article quality way. Here are those unit conversions from my sandbox, for the record:

km/h and mph conversions, assuming 90,000 feet altitude for Mach 6 and 120,000 feet altitude for Mach 10, which approximates the launch profile for this RP1/LOX first-stage booster.
- {{convert/q|6|Mach|90000|abbr=on}} yields: Template:Convert/q
- {{convert/q|10|Mach|120000|abbr=on}} yields: Template:Convert/q

km/s conversions, assuming 90,000 feet altitude for Mach 6 and 120,000 feet altitude for Mach 10, which approximates the launch profile for these RP1/LOX first-stage boosters.
- {{convert/q|10|Mach|km/s|mph|120000|sigfig=2|disp=flip|sp=us|abbr=on}} yields: Template:Convert/q

Proposal for handling the Mach no. sources

I propose we take the rough agreement that is emerging above and handle the Mach nos. in that paragraph this way: approximate km/s (conversions to km/h, mph, and Mach), all rounded to two significant digits. N2e (talk) 19:29, 1 January 2014 (UTC)[reply]

Example of the proposed change:

"... the first stage separation would occur at approximately 2.0 km/s (6,500 km/h; 4,100 mph; Mach 6) rather than the much faster 3.4 km/s (11,000 km/h; 7,000 mph; Mach 10) for an expendable Falcon 9..."

Here is the current way they are rendered, the way that got us through the B-level article review, but may not get us through the GA review.

"... the first stage separation would occur at 6,546 km/h (4,067 mph; Mach 6) rather than the much faster 11,200 km/h (6,960 mph; Mach 10) for an expendable Falcon 9..."

Done—Okay, since it has been a week, I've gone ahead and made the proposed change to clean up the stage separation velocities, in line with the consensus in the discussion above. Used the {{convert/q}} numerical conversions as summarized in the section immediately above. N2e (talk) 23:29, 6 January 2014 (UTC)[reply]

Source

A fairly in-depth article appeared on NASA Spaceflight earlier this month. Here's the link. Plan to hold off combing this for new info until after the thorough copyedit (currently underway) is complete. N2e (talk) 01:15, 5 February 2014 (UTC)[reply]

Still needs looked at when time is available. N2e (talk) 19:49, 13 March 2014 (UTC)[reply]

February 2014 Copyedit

A major copyedit of the article is currently underway. It is being done by a request to the Guild of Copy Editors, and, specifically, by Baffle gab1978. This is a very good thing, and will much improve the article.

Copyeditor comments and requests

TBD

Questions/notes by others

SpaceX has made clear (sourced in the body) that this reusable launch technology is key to all of their future rockets, even beyond the currently operational Falcon 9 and the late-in-development, soon-to-be-operational Falcon Heavy. So whatever methane-engine rockets are developed, and new larger rockets that are still in early development would be included. Should we make this clear in the lede section? N2e (talk) 01:36, 5 February 2014 (UTC)[reply]
The third paragraph of the History section may conflate the first Grasshopper test vehicle (Grasshopper v1.0) with the second (Grasshopper v1.1). The "second" is referred to in the beginning of the paragraph; while the prose switches to the first Grasshopper later in the para, without making the switch explicit. N2e (talk) 01:36, 5 February 2014 (UTC)[reply]
The first para of the lede includes: "Both stages are designed to be available for reuse a few hours after return." This is a long-term objective, not really something that is already in the "current design"--although it is fair to say that the major mechanical parts (tanks, tank structures, rigidity, attachment points, etc.) are all "designed" (as is) to support that objecgtive. However, there is a lot of software design, attitude control algorithms, navigation, etc., etc. on the vehicle that is still/yet being designed as they go through the flight test program. As well, a large amount of ground infrastructure and operational procedures are not yet in place to support the "few hours" long term objective. Maybe some slight rewording would be useful? N2e (talk) 01:36, 5 February 2014 (UTC)[reply]
Did you copyedit the Technologies section? I didn't notice any edit comments from you on that section? N2e (talk) 04:27, 6 February 2014 (UTC)[reply]
- Done Looks like Baffle gab came back at 2014-02-06T05:12:11‎ Baffle gab1978 and copyedited that particular section.
In the intro to the Grasshopper section, it says: "Four additional test flights were made in August 2013." That's not quite right. The old text was correct (but incomplete, I now see): "Four additional test flights have been made through August 2013." It is true that four additional flights had been made by August 2013, in addition to the three already mentioned. But an eighth, and final, test flight of the GHv1.0 vehicle was made in Oct 2013. So, perhaps, we might say something like: "Five additional test flights have been made through October 2013." Or you may have better ideas? N2e (talk) 04:44, 6 February 2014 (UTC)[reply]

I find the use of "through" confusing in this context. I'd normally expect to find that preposition used to describe a physical thing/location, such as "the cat ran though the kitchen", and not to indicate the end of a time period. In this context I'd expect a different preposition, such as "by the end of August...". How about replacing it with "Five more test flights had been carried out by the end of October 2013", or "SpaceX carried out the eight—and final—test flight of the vehicle on October 19, 2013"? Cheers, Baffle gab1978 (talk) 18:31, 6 February 2014 (UTC)[reply]

Sure, I'm fine with one of your ideas. The point was just that the copyedit left it incorrect on a small technical detail: there weren't four flights made in August of 2013. Cheers. N2e (talk) 03:50, 7 February 2014 (UTC)[reply]

Done—I changed one instance of "through October" to "by the end of October". Cheers, Baffle gab1978 (talk) 23:05, 7 February 2014 (UTC)[reply]