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What do you think?

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Comments moved here from Wikipedia talk:WikiProject Aircraft#Wing configurations. -- Cheers, Steelpillow (Talk) 21:27, 19 June 2008 (UTC)[reply]

Looks interesting - but it needs references added! - Ahunt (talk) 18:28, 15 June 2008 (UTC)[reply]
Ditto - with some references will be a useful article here, but that shouldn't be hard since there are quite a number of aeronautical/aviation dictionaries around. A few more suggestions: shoulder wing, gull (and inverse-gull) wing, wire-braced vs strut-braced (maybe flying struts?), lifting body. Note that some people seem to use "multiplane" to refer to anything that isn't a monoplane. Cheers --Rlandmann (talk) 20:14, 15 June 2008 (UTC)[reply]
Thanks. References are a problem for me - most of it came from memory, and I do not know of any dictionary for this aspect of aircraft design. Not sure what to do about this. Any ideas? I have added the other suggestions. -- Cheers, Steelpillow (Talk) 19:32, 16 June 2008 (UTC)[reply]
I think most of us here have some good refs for that article if you don't. How about you go ahead and create the article, let us know here where and when it is posted and then we can see if we can fill in the blanks on the refs? - Ahunt (talk) 00:49, 17 June 2008 (UTC)[reply]
With a few references this could be a featured list! --MoRsE (talk) 12:40, 7 September 2009 (UTC)[reply]
Would it mess things up to provide links to one example per configuration, e.g. for Gull-wing the Short Knuckleduster, for inverted gull-wing the F4U Corsair etc? Actually an in-line thumbnail illustration of each type would be better! --TraceyR (talk) 14:32, 7 September 2009 (UTC)[reply]
One linked example per configuration is certainly good, maybe two or three in exceptional cases. But inline thumbs would be so densely cluttered that they would mess up the page layout. So I opted for "banners" of abstracted images at convenient break points. -- Cheers, Steelpillow (Talk) 20:24, 7 September 2009 (UTC)[reply]

Wing twist

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Looking to place wing twist or washout in the wing configuration page. There is a nice description below in the Wing configuration Eliptical wing section which should be incorporated under a heading such as dihedral with a drawing.Pgr0 (talk) 18:02, 15 July 2012 (UTC)[reply]
Not sure if this is really about the configuration, it's one of those subtleties like reverse camber, root fillets, control surfaces and so on that are kind of add-ons to the main configuration but aren't intrusive enough to be "minor surface features". — Cheers, Steelpillow (Talk) 18:31, 15 July 2012 (UTC)[reply]

Double delta

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Is the double delta design equal to the "Compound delta" design? --MoRsE (talk) 19:29, 2 July 2008 (UTC)[reply]

Effectively, yes. I guess that technically a compound delta could have more than two leading-edge sections with different angles, but I cannot recall ever seeing this done. -- Cheers, Steelpillow (Talk) 15:08, 3 July 2008 (UTC). P.S.: I have updated the article accordingly.[reply]
Actually, the production models of the Avro Vulcan had a wing extension which created three leading-edge sections all with different angles. -- Cheers, Steelpillow (Talk) 21:10, 7 September 2009 (UTC)[reply]

Illustrations

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I just drew up some illustrations. What do you think? I don't know why the text has gone fixed-pitch, in the source file it is sans. -- Cheers, Steelpillow (Talk) 20:26, 22 August 2009 (UTC)[reply]

Meanwhile there are some blue diagrams of individual planforms on the Commons, here. Do you people think they are suitable for this article? -- Cheers, Steelpillow (Talk) 13:51, 23 August 2009 (UTC)[reply]

I like the illustrations - clear and intelligible to all-comers. I'd like to suggest two additions: the V-shaped flying wing (e.g. the Dunne D.5) and the tailless Short Sherpa configuration. --TraceyR (talk) 14:56, 5 September 2009 (UTC)[reply]
Thanks. I did the tail vs. tailless bit with delta wings because those drawings already existed. I agree that using swept wings would be better. -- Cheers, Steelpillow (Talk) 16:37, 5 September 2009 (UTC)[reply]
There's an illustration of the Barnes Wallis Swallow here, which belongs to a further category - both tailless and variable geometry. How about an illustration this one too? Perhaps its time will come... :-) --TraceyR (talk) 11:25, 7 September 2009 (UTC)[reply]
What about the crescent wing, and an illustration of the Delanne tandem if only for the tandem wing article?GraemeLeggett (talk) 15:22, 7 September 2009 (UTC)[reply]
There are so many combinations that listing them all would be pointless. The lead makes it clear that any given aircraft displays a combination of several types of feature. -- Cheers, Steelpillow (Talk) 20:29, 7 September 2009 (UTC)[reply]

Drawing style

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Well, I added some. Now there are two different styles, thick monochrome outline for the frontal elevations and blue solid with thin outlines for the planforms. I am thinking of doing them all the same style. Any preferences? -- Cheers, Steelpillow (Talk) 21:24, 3 September 2009 (UTC)[reply]

I like what you have done! On the planform views, though, I would recommend making the nose look more like a nose rather than a mirror image of the tail end. I also think the fuselage shapes need a heavier outline and shading other than blue might work better – on the default skin they tend to blend into the background. (Oh, and on the swept wing image, move the wings aft, closer to the center of gravity; they’re too far forward.) Askari Mark (Talk) 01:24, 4 September 2009 (UTC)[reply]
Those criticisms of the blue diagrams agree with my own. I'll probably create new ones rather than rework somebody else's. -- Cheers, Steelpillow (Talk) 10:06, 5 September 2009 (UTC)[reply]
My first impression, is that they are "precious" and "cute" but essentially useful. FWiW Bzuk (talk) 01:54, 4 September 2009 (UTC). (comment moved from WikiProject Aircraft talk page -- Cheers, Steelpillow (Talk) 09:57, 5 September 2009 (UTC)[reply]
Do those criticisms apply to the frontal elevations, the plan views, or both? -- Cheers, Steelpillow (Talk) 10:06, 5 September 2009 (UTC)[reply]
I think the wings on "swept" are too far forward on the plane, it looks out of balance. GraemeLeggett (talk) 19:16, 9 September 2009 (UTC)[reply]
Different eras had different characteristics, it is all very subjective. It's important that the digrams look "right" alongside each other. I'll take another look at some point. -- Cheers, Steelpillow (Talk) 09:48, 13 September 2009 (UTC)[reply]

Anything to fix?

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I just finished all the drawings I had planned. Is there anything I have missed or got wrong (or just done so badly that it needs doing better)? -- Cheers, Steelpillow (Talk) 20:44, 22 September 2009 (UTC)[reply]

Wing configuration categories?

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Would it be useful to have a category for each of the different wing configurations? I see that there is a category 'Flying wing aircraft' and one for 'Triplane aircraft', so the precedent has been set. AFAICS there aren't categories for e.g. gull-wing, inverted gull-wing etc. I think that they could be a useful addition. What do others think? --TraceyR (talk) 14:51, 7 September 2009 (UTC)[reply]

For most of them yes, though I think that categories for say wire-braced vs. strut-braced would be useless. Unlike the actual article, sub-categories for a few popular combinations, such as Category:Tailless deltas and Category:Canard deltas, would be good too. -- Cheers, Steelpillow (Talk) 20:39, 7 September 2009 (UTC)[reply]
I've started the category "Gull wing aircraft", suggesting in the text that there be a second category for inverted gull wing aircraft, but now I'm not sure about this. Would it be better to include inverted gull wing aircraft in the same category? All comments and ideas more than welcome, since it it better to sort this sort of question out before people invest their time adding aircraft to categories that are then disputed! --TraceyR (talk) 09:36, 8 September 2009 (UTC)[reply]
The categories need the parent category "aircraft configurations", and where there are many examples they might qualify for the hidden category status like "high wing aircraft".
I note also, that the Lysander has straight spars, and isn't a gull wing. From the article "The wings had an unusual reverse taper towards the root". GraemeLeggett (talk) 11:28, 8 September 2009 (UTC)[reply]
Thanks for the Lysander detail, now corrected. I wonder whether we should compile a list of proposed category names to avoid inconsistencies. Would a category "Canard delta-wing aircraft" be necessary, because e.g. the Saab Viggen could have two categories, "Delta-wing aircraft" and "Canard wing aircraft" (or whatever); do we need such detailed categories. Is there a policy on this? Thanks --TraceyR (talk) 15:39, 8 September 2009 (UTC)[reply]
Opinionated replies to several points: inverted gull wings are known as cranked wings - the Junkers Ju 87 is the classic example. Category:Wing configurations is better here - it should be a sub-category of Category:Aircraft configurations. Detailed sub-categories only make sense where there are a large number of aircraft to go in them. -- Cheers, Steelpillow (Talk) 18:40, 8 September 2009 (UTC)[reply]
Yes, I think that 'wing configs' should be a sub-cat of 'aircraft configs', along with twin-boom aircraft, rotorcraft, ekranoplanes etc. For most sub-cats of 'wing configs' there will be plenty of aircraft (I'm not too sure of the value of the 'low wing', 'high wing' etc cats, but they don't do any harm!). I've looked quickly through WP and added the 'gull wing' cat to several articles.
I must admit that I have never heard the term 'cranked wing' and wouldn't have known what it meant; 'inverted gull wing' seems more common to me; I googled the term and the first one it threw up was this, which is a level wing with a dihedral outer section (like the F-4 Phantom), i.e. neither gull wing nor inverted gull wing. Perhaps 'cranked wing' is the superset of gull-wing, inverted gull-wing and any other wing with two or more angles of anhedral/dihedral. BTW '"cranked wing" aircraft' returns 1,420 g-hits, '"gull-wing" aircraft' gets 18,300 and '"inverted gull-wing" aircraft' gets 98,000! Of course it's not conclusive and includes WP and all of its 'friends' but it perhaps gives an indication. --TraceyR (talk) 20:35, 8 September 2009 (UTC)[reply]
The “cranked” wing is a variant of the inverted gull wing with the inboard wing section horizontal and the outboard dihedral sections canted upward. Jodel is one of the few companies to use it much. The cranked-arrow delta wing used on the F-16XL is totally different as it has the crank in the horizontal plane. Askari Mark (Talk) 03:50, 9 September 2009 (UTC)[reply]
What a lot of disinformation there is on the Internet about cranked wings! None of these usages comes from a respectable reference, and I know that some are technically wrong. Let us tread carefully here. -- Cheers, Steelpillow (Talk) 08:28, 9 September 2009 (UTC)[reply]
Yes, there's a load of rubbish out there (and even on WP, sad to say). I have just come across a technical paper (an MSc thesis) which uses the term 'cranked wing' to refer to a delta planform with (at least?) two degrees of sweep (look at fig. 18 on p.21, actually the 29th page). Also the Boeing sonic cruiser] is described as having a 'double-delta, or "cranked arrow", wing combining a high-speed inboard section and a higher aspect ratio outboard section reminiscent of conventional Boeing wings'. Does "cranked arrow" refer to changes in sweep in the horizontal plane and "cranked wing" to changes in dihedral? Or does it include both types? --TraceyR (talk) 09:18, 9 September 2009 (UTC)[reply]
Technically – that is, not used sloppily – "cranked wing" refers to a wing with an outboard dihedral (or anhedral, theoretically I suppose, although I cannot think of an example offhand), while the "cranked arrow" has different leading edge (and usually trailing edge) sweeps for the inboard and outboard wing sections. "Cranked wing" should not be used to refer to a cranked-arrow wing, but sometimes some people do so. Askari Mark (Talk) 02:09, 10 September 2009 (UTC)[reply]
Just to check: A cranked wing has a horizontal inboard wing section and an outboard section with positive or negative dihedral, i.e. the Phantom has a cranked wing but the Ju-87 has an inverted gull wing? So is a cranked wing distinct from gull wing and inverted gull wing and should have its own category? Thanks for helping to clear this one up - as I mentioned before, the term is new to me! --TraceyR (talk) 12:19, 10 September 2009 (UTC)[reply]
There is a document which might shed light on current usage of "cranked". ( 76003 Datasheet "Geometrical properties of cranked and straight tapered wing planforms". ESDU. something to do with RAE). this article in Flight from 1942] - which would be a good reference for this article - gives cranked as an alternate name for inverted gull. It also clarifies that gull wings to not have to have anhedral on the outer sections. GraemeLeggett (talk) 13:13, 10 September 2009 (UTC)[reply]
Thanks Graeme, that looks conclusive - although usages change, of course, but if we can equate "cranked wing" with "inverted gull wing", as in the Flight ref., great. I suppose a gull wing is therefore one which has a dihedral inboard wing section and an outboard section with a lesser angle of dihedral. Would this defininition (mutatis mutandi) be OK for inverted gull wing too? --TraceyR (talk) 14:29, 10 September 2009 (UTC)[reply]
As I was taught (back in the latter half of the 1970s), the F-4 was “cranked” and the Ju-87 had an “inverted gull” wing. Perhaps these were synonyms in 1942, or possibly it’s a matter of American vs. English usage. (Or maybe it was explained to me wrong all those years ago … in which case I guess I should fire the prof!) If they’re synonyms, it does beg the question, though, of why a gull wing isn’t called “cranked” as well. I also have commonly seen cranked-arrow wings called “cranked wings” (even though it’s just a case of different outboard/inboard wing sweep). Here’s an article on cranked-arrow wing pitch-up that does so in at least one place (page 10). I’ve also found the term used to describe the wing on the Predator C, which is “cranked” only on the trailing edge. Just to round things out, here’s a source that actually calls the cranked wing a “seagull-type wing”. In any case, I wouldn’t recommend using “cranked” as a category”. It would seem to be too confusing. Askari Mark (Talk) 02:36, 11 September 2009 (UTC)[reply]

This NASA ref from 1995 uses it for a "waverider" wind-tunnel model with a pronounced upward curve from about 2/3 out. Interestingly, the authors found it necessary to define what they meant by "cranked":

The term "cranked" in this case refers to a shape where the sweep angle not only changes, but alsowhere the leading edge curves upward to add a significant amount of dihedral in the aft portion of the wing. The cranked-wing shape was designed to provide improvements in subsonic aerodynamic performance due to a small increase in aspect ratio as well as improvements in lateral-directional stability over the straight-wing design.

I'm coming to the conclusion that "cranked" was not as specific as either "gull wing" or "inverted gull wing"; these seem imply a wing with a change of dihedral/anhedral along the wing, generally (but with exceptions!) starting with one and changing to the other - at least that's how I understand them. Does cranked just mean "bent" in some way? --TraceyR (talk) 06:29, 11 September 2009 (UTC)[reply]

Following on form the previous comment, this article states

The Mariner first appeared in 1937 as the Martin Model 162 project, giving birth to the prototype XPBM-1 as a twin engine flying boat with a high-mounted monoplane gull wing (cranked at the engine nacelles), ...

indicating that "cranked" just indicates a bend without specifying in which direction. --TraceyR (talk) 09:54, 11 September 2009 (UTC)[reply]
OK, I updated the article to try and make sense of all this. -- Cheers, Steelpillow (Talk) 11:29, 15 September 2009 (UTC)[reply]
That's good - we're getting there! Could you add a diagram showing the F-4 cranked wing configuration (with a fixed undercarriage, of course!)? Are there any examples of aircraft with the inverted config., i.e. level then with outboard anhedral section? --TraceyR (talk) 13:01, 15 September 2009 (UTC)[reply]
Quick work, Steelpillow!! I think that the work you have put in deserves a barnstar - I'll have a look for one (unless someone else beats me to it!). --TraceyR (talk) 18:21, 15 September 2009 (UTC)[reply]
Actually, I had already drawn it when I read your comment. The BAC TSR-2 had a flat wing with anhedral tip sections. A slight main wing with slight dihedral and sharply downturned tips is the one sometimes described as a "ruptured duck" - not sure if that monicker is used only for tailless designs. Thanks for the barnstar, not sure I deserve it yet as there are still a few illustrations to go. -- Cheers, Steelpillow (Talk) 20:07, 16 September 2009 (UTC)[reply]

Horizontal stabilizer pics

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How about a pic of the T-tail and the Cruciform tail?GraemeLeggett (talk) 20:55, 9 September 2009 (UTC)[reply]

I think that these (and more) properly belong in the empennage article. -- Cheers, Steelpillow (Talk) 16:29, 15 September 2009 (UTC)[reply]
Very much so, I meant did you feel up to doing some more pictures. There's currently a sort of animated gif trying to show them at the moment. GraemeLeggett (talk) 15:43, 17 September 2009 (UTC)[reply]
maybe eventually. I want to finish the ones for this article first - some need "3D perspective" views, which will keep me quiet for a while. -- Cheers, Steelpillow (Talk) 19:31, 17 September 2009 (UTC)[reply]

This page's categories

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There's a long list of categories on this talk page, some of which seem, to my inexperienced eye, to be inappropriate. Shouldn't some of the categories which suggest that this is a poor article be removed now? --TraceyR (talk) 09:59, 11 September 2009 (UTC)[reply]

I guess that most are added automatically as a result of the banners and tags. I can't see a particular tag that pertains to the grammar but it may be a function of the WP aviation assessment. Lets see what happens once I've assessed the article. GraemeLeggett (talk) 11:37, 11 September 2009 (UTC)[reply]
The categories have decreased with the reassessment. I've asked a member of the Physics/fluid dynamics for an input of their side of article quality. GraemeLeggett (talk) 11:49, 11 September 2009 (UTC)[reply]

Reverse taper on root section

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Some types, such as the Westland Lysander have reverse taper on the inner wing section near the root. Does anyone know if this arrangement has a special name? If it does not, is it still worth adding to the "Variation along span" section? -- Cheers, Steelpillow (Talk) 20:51, 22 September 2009 (UTC)[reply]

Its probably more a function of providing a good view than an aerodynamics, I wouldn't add it to variantion along span until we can why. GraemeLeggett (talk) 12:00, 21 February 2010 (UTC)[reply]
Yes, it is done for visibility - the Lysander was an observation aircraft. I did add it some while ago and describe it as "compound tapered", with a diagram too. -- Cheers, Steelpillow (Talk) 14:47, 21 February 2010 (UTC)[reply]
I guess that description could include other variations, such as compound delta and cranked arrow, but "compound taper" is possibly just a convenient description for use here, and may not be a term found in references, so I am reluctant to make a big thing of it. OTOH the article does need a descriptor, so I had to choose something. -- Cheers, Steelpillow (Talk) 14:47, 21 February 2010 (UTC)[reply]
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I feel that this article meets the standards now, som I am nominating it to the Featured lists :) --MoRsE (talk) 16:43, 29 January 2010 (UTC)[reply]

Sorry, but I have removed the nomination; the article needs a lot of work, and only the primary contributors should be submitting lists to FLC. Dabomb87 (talk) 22:24, 29 January 2010 (UTC)[reply]

Wing support

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I can see that in this article the emphasis is, properly, on appearance rather than function, so we do not want to go too far into the engineering details. It is, though misleading to say the external wing struts on a high wing aircraft (Cessna 172 say) are supporting the wing and in compression. That is true on the ground, but in flight they are in extension, conveying the lift generated by the wings to the aircraft's fuselage and its load, as well as preventing the wings folding upwards. Hence the name lift struts, though they may also carry drag forces Some low wing aircraft (Piper Pawnee, for example) have lift struts that are in compression in flight because they are above the wing.TSRL (talk) 22:22, 20 February 2010 (UTC)[reply]

Thanks for pointing that out. Hope it's better now. -- Cheers, Steelpillow (Talk) 10:30, 21 February 2010 (UTC)[reply]
Cheers. That covers it.TSRL (talk) 15:18, 21 February 2010 (UTC)[reply]

Sweep

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Couple of thoughts:

  • It's true that for the last 60 years or so, sweep has been associated with fast aircraft, employed to delay compressibility effects but sweep was very common (not just used occasionally) on biplanes (even with constant chord wings, see below), presumably for visibility reasons as well as getting the cp in the right place and reducing its movement, rather as stagger was used.
  • Sweep is usually defined by the 1/4 chord line, so deltas are swept but so is the Douglas DC-3 and many others with leading edge sweep but straighter trailing edges. So again, sweep is quite common on slow aircraft.

Points worth making?TSRL (talk) 15:10, 21 February 2010 (UTC)[reply]

I have tried to clarify the use of small angles for adjustment of CP relative to CG. It's bad to say too much, as the page soon loses focus. -- Cheers, Steelpillow (Talk) 20:57, 21 February 2010 (UTC)[reply]
That helps. Take the point about detail, so linked to swept wing.TSRL (talk) 08:51, 22 February 2010 (UTC)[reply]

Sweep was used as early as 1907 to achieve longitudinal static stability by one of the pioneers of aviation, John William Dunne, see also Swept_wing#History. Would a brief mention of this aspect (with wl) be useful? --TraceyR (talk) 22:01, 22 February 2010 (UTC)[reply]

OK, done that too. Needed a bit of reworking to keep things coherent. 83.104.46.71 (talk) 20:05, 23 February 2010 (UTC)[reply]

World's first variable geometry wing

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The French Makhonine MAK-10 is referred to as the world's first variable geometry wing. Surely this description belongs to the Pfitzner Flyer which introduced wing extensions in 1910, albeit as control surfaces to induce roll moment rather than to increase/decrease wing area and or sweep. --TraceyR (talk) 09:28, 27 November 2010 (UTC)[reply]

Back in 1975 Air International in is March 1975 issue did what is considered the largest and best article on VG aircraft and wings. They got together with aircraft engineers and came up with VG being able to radically alter a "wings proper" in flight excluding the control surfaces. The reason being that flaps, slats, etc. would make any aircraft have a VG wing. But if you can disagree, I have no problem with you changing it. But when AI wrote the article, no one (and about anyone in the aviation industry and historians read either FLIGHT or AI) contested the article and its conclusion about the MAK-10. Jack Jackehammond (talk) 10:17, 27 November 2010 (UTC)[reply]
It's a matter of definition, isn't it. The MAK-10 had telescopic wings which altered the wing area and aspect ratio; the Pfitzner Flyer had telescopic wings which also varied the wing area and aspect ratio on each side while keeping the total wing area constant. Since both are mentioned in the variable geometry section of the article and since the wing geometry is varied on both aircraft, some wording needs to be added to justify the claim made for the MAK-10 being the first. It's certainly possible that Air International did not know about the Pfitzner Flyer's telescopic wings; Wikipedia in 2010 has the chance to be more accurate than AI 35 years ago.--TraceyR (talk) 12:01, 27 November 2010 (UTC)[reply]
I am inclined to agree with the AI analysis - we do not treat extensible slats or Fowler flaps as variable-geometry but as control surfaces, even though they effectively extend the wing area. I think the Pfitzner Flyer's extensions come under the same analysis, especially as they were specifically intended as control surfaces. I'll change the article. — Cheers, Steelpillow (Talk) 22:38, 27 November 2010 (UTC)[reply]
I note that the extending wingtips only moved 15 inches, and that since there is no fuselage although there is a dihedral there isn't really "each side" to the wing. Not that my opinion has any bearing on what the experts say, and if no source says the Pfitzner is the first it isn't. GraemeLeggett (talk) 22:53, 27 November 2010 (UTC)[reply]

Folks, On another subject of weird wing configuration please check Talk:Nikitin-Shevchenko IS#Some pages that will help from article and look at the drawings - Unbelievable! Jack Jackehammond (talk) 06:47, 28 November 2010 (UTC)[reply]

Is a shoulder wing a type of high wing?

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I would say yes: I have several books by reputable authors which describe shoulder-wing types as having a high wing. Apparently at least one dictionary can be interpreted to disagree with this. Does anybody have any further references to back up the idea that a shoulder wing is not a type of high wing? We could have an ambiguous situation on our hands.

Meanwhile I'd be grateful if my original edit could be left un-reverted until this is cleared up, as per Wikipedia's dispute guidelines.

— Cheers, Steelpillow (Talk) 19:36, 23 August 2011 (UTC)[reply]

I don't have ready access to a citable reference but I agree that what some people call a shoulder wing is the same as other people call a high wing. I can suggest the following criterion. Low wings require substantial dihedral for lateral stability. High wings don't require dihedral because the fuselage has a blocking effect on any lateral flow - in a sideslip pressure builds up a little more under one wing than under the other because the fuselage doesn't allow the two pressures to equalise in the way that would happen in a low wing aircraft. The difference in pressure under the two semi-spans causes the aircraft to roll in the desired direction to give lateral stability. If an aircraft has a wing with substantial dihedral it is a low wing aircraft; and if it doesn't have substantial dihedral it is a high wing aircraft.
I think there is good coverage of this subject in one of Darryl Stinton's books. I will have a look and see if I can find a good citation to support our view.Dolphin (t) 23:17, 23 August 2011 (UTC)[reply]
A shoulder wing has similarities to a high wing, but is "sui generis". Otherwise, you could say that a shoulder-wing is a high sort of mid-wing, and so on, ad nauseam. Some aircraft (particularly the Bolkow, ARV & Saab safari were designed with a shoulder wing precisely because it didn't have the disadvantages of a high wing (i.e. poor visibility in turns). User:arrivisto Arrivisto (talk) 14:29, 24 August 2011 (UTC)[reply]
I'd be reluctant to base the definition on di/anhedral because some low-wing types (especially sharply-swept types) have anhedral while some high/shoulder wing types (especially seaplanes) have dihedral. If Arrivisto is right - and I'd like to see a bit more than the flat assertion that the two are sometimes contrasted as explicitly distinct - then we do have an ambiguous situation on our hands. While we discuss it, I would ask Arrivisto to respect the three-revert rule on edit wars. — Cheers, Steelpillow (Talk) 18:47, 24 August 2011 (UTC) Also, being logical is not Wikipedia's job - it has to reflect the real world's foibles. — Cheers, Steelpillow (Talk) 18:52, 24 August 2011 (UTC)[reply]

As indicated before, the term "main fuselage" seems meaningless (is there a main and a lesser fuselage?). Secondly, there is no justification for making a shoulder wing a subcategory. Thirdly, it is clearer, more elegant and more logical to go in steps from low to mid to shoulder to high to parasol. Fourthly, the line "(as opposed to mounting on the cockpit fairing or similar)" seems meaningless. Fifthly, since manufacturers (of say, ARV Super2) specifically chose the shoulder wing to avoid the horrors of a high wing, it seems odd to try to put them together. Sixthly, a high wing makes it easy to adopt a correct CofG position; whereas a shoulder wing gives enhanced visibility, but (on a light aircraft) the wing must be swept forwards (ARV, Bolkow, Saab) to main tain correct CofG. However, the forward sweep allows a more efficient (& therefore smaller) wing, as the span-wise flow of air on the upper surface flows towards the fuselage, not away, thereby reducing wingtip vortex drag. Seventh, the dictionary reference provided seems to declare a shoulder wing a type all of its own. In short, while a shoulderwing has some similarities to a high wing, it is not helpful nor to call it a type (or sub-category) of high wing. Would you say a mid wing is a category of low wing? Surely not!

(Note that the special benefits, i.e. visibility & efficiency, of a shoulder wing apply mainly to light aircraft; large aircraft may choose a shoulder wing for their own reasons).

Sorry to have appeared to enter an "edit war", but (as a shoulder-wing pilot) I do feel I reasonably qualified to comment. No offence meant! Arrivisto (talk) 12:16, 25 August 2011 (UTC)[reply]

To take those points in turn:
1. I contrasted the "main fuselage" with the idea of a wing mounted on say the cockpit roof, which is structurally part of the fuselage but physically elevated above it. If you can find a clearer way to say that, fine.
2. There may or may not be logical justification, but linguistic usage by many sources provides encyclopedic justification that we should not ignore.
3. I repeat, what is logical and what is found in the real world are not the same thing. Wikipedia is an encyclopedia not a text book.
4. See 1 above.
5. See 2 above.
6. See 3 above.
7. Online dictionaries are not always reliable. I asked whether the one cited is acceptable here and have had no satisfactory demonstration that it is. Further, other references contradict it and I am not ruling out the need to accommodate an ambiguity of usage.
No offence intended here, but being qualified does not give one the right to pre-empt others (I know that to my cost in other topic areas). Qualification merely gives one the foreknowledge to spot a mistake and go root out a reliable reference to the truth. I am not saying you are wrong, merely that I was not aware of your PoV (as you were not aware of mine) and that any verifiable PoV needs to be respected. I guess I'd better go root out some references to support my PoV.
Meanwhile we still need to reach consensus on formatting that dratted bullet list. I'm not going to fight for that, provided the text respects both PoVs. — Cheers, Steelpillow (Talk) 20:57, 25 August 2011 (UTC)[reply]
Have updated the article to clarify different usages. Arrivisto's logical sequence makes sense now. — Cheers, Steelpillow (Talk) 14:27, 27 August 2011 (UTC)[reply]

Hi, By the way, can anyone please supply a citation to support this statement: "A shoulder wing is like a high-wing, in producing a pendulous fuselage requiring no wing dihedral; and its limited ground effect reduces float on landing"?Arrivisto (talk) 12:44, 25 August 2011 (UTC)[reply]

At last I see where you've been coming from! I agree with you that on a large aircraft, the significance of a shoulder wing is negligible and it may as well be deemed a sub-type of high wing; it's just that on a small 2-seater like the ARV (or Saab or Bolkow), the significance is huge. cheers Arrivisto (talk) 15:01, 30 August 2011 (UTC)[reply]

Two years down the line

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and here we are having the same old discussion. I maintain that there are (at least) two mildly incompatible usages of the term "high wing" and that readers need to be told about both, while Arrivisto (talk seems to favour a single PoV. I can only ask, has something changed in the last two years to invalidate the other PoV? — Cheers, Steelpillow (Talk) 19:38, 27 May 2013 (UTC)[reply]

Horizontal stabilizer

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A canard (lifting or not) surface looks like a stabilizer (same general dimensions) but is NOT stabilizing at all; as located ahead of the CG, it is strongly destabilizing. It provides added lift and/or pitch control. The aft wing (the horizontal tail or the main wing in the canard case) IS always the stabilizing surface. The pitch stability comes from the lift slope difference between the front and the back surfaces.Plxd (talk) 12:26, 21 October 2011 (UTC)[reply]

An technical argument can be had about which surface stabilises the action of the other. However Wikipedia must respect normal use of language, and here the foreplane is commonly referred to as a "stabiliser" or "stabilizer", even where the airframe has no inherent stability. [Edit] I also know pedants who insist that the correct term for a tailplane is "horizontal stabiliser", again even when the airframe is unstable and the tailplane has no slope difference, hence no stabilising effect! — Cheers, Steelpillow (Talk) 19:13, 21 October 2011 (UTC)[reply]
"Horizontal stabiliser" is no better than "tailplane", and "vertical stabiliser" is no better than "fin". And "primary lift surface" is no better than "wing"! Once again, one finds that we are divided by a common language!. Arrivisto (talk) 09:33, 28 October 2011 (UTC)[reply]
Surely "tailplane" is more specific, in that it specifies the location of the "horizontal stabiliser", so in this sense at least they are not interchangeable. Tailplane is less specific about its function. I'm not happy about referring to something as a "stabiliser" if that is not its purpose. FWIW I feel happier with "tailplane" than e.g. "rear-mounted horizontal stabiliser". --TraceyR (talk) 10:43, 28 October 2011 (UTC)[reply]
The problem faced in the present context is to find a generic word for both fore- and tail-mounted auxiliary horizontal planes (i.e. shorter and snappier than "auxiliary horizontal plane". The term "stabiliser" is commonly used, without regard as to whether it is technically correct for any given model - guess that's because historically (before relaxed static stablity came along) they were always stabilisers. The modern introduction of both surfaces (the tandem triple) has broken the mould a little, with phrases like "auxiliary lifting surfaces", "control planes", etc. being used by one writer or another - but again, what is technically correct for one arircaft or flight mode might not be for another (if a control surface is neutrally trimmed then it is not a lifting surface, while if a lifting surface is fixed then it is not a control surface, while either of these might or might not be having a stabilising effect at the time, one can argue that a computer-controlled surface is in fact performing an "active stabiliser" function even if the airframe is statically unstable, etc. etc.). IMHO Wikipedia should stick to the old-established common usage, unless/until a new standard terminology becomes established in the literature. The niceties can then be explained in the appropriate article, but I do not think that this article is the appropriate place. [Edit] Meanwhile, I am wondering how many instances of "stabiliser" can simply be cut from the offending paragraphs. — Cheers, Steelpillow (Talk) 11:30, 29 October 2011 (UTC)[reply]
Something else to think about: are "horizontal stabilisers" actually horizontal? Certainly there are plenty with anhedral/dihedral. What they do have in common is that they all stick out sideways (Oops! Laterally). --TraceyR (talk) 11:48, 1 November 2011 (UTC)[reply]

Wikipedia must respect normal use of language, "stabiliser" is recognized even by the spell checker in this Wikipedia edit window as a typo. Try "stabilizer". If you try searching on Google the vote is 57 million to 9 million. It is not acceptable to propagate errors of language in a reference work. Correcting common misunderstandings is part of the educational function of a reference work. --Stodieck (talk) 18:03, 19 May 2012 (UTC)[reply]

"Horizontal stabiliZer" is better than "tailplane" because it is somewhat self-defining and less prone to misunderstandings. It is the "technical term".

Horizontal stabilizers are not required to have a slope difference to be stabilizing, this is not dihedral. They normally have a negative lift to hold the nose of an airplane up if the center of gravity is located ahead of the center of lift of the main wing. Having the center of gravity is located ahead of the center of lift is what creates stability. The negative lift is actually a pitch control function not part of the stabilization. The horizontal stabilizers on some three surface aircraft are in fact normally flown at neutral lift. Something you could read about in this article if Steelpillow hadn't deleted the entries and citations on three-surface and 3-lifting-surface aircraft "wholesale" from this article.

"find a generic word for both fore- and tail-mounted auxiliary horizontal planes" Using "forward wing" or "small forward wing" instead of "canard" helps reduce confusion immensely. As things are, canard should always be qualified. I.e. "canard wing" or "canard aircraft" Tailplane is really OK as it is, but people misuse it.

I suggest that this section heading be changed to Horizontal stabilizer configurations. That what the section addresses not Horizontal stabilizers. --Stodieck (talk) 18:16, 19 May 2012 (UTC)[reply]

Elliptical wings

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Allow me to explain why I undid an edit by 'Steelpillow'

Most simply, the point/reference about 'semi-elliptical' wings - if you look carefully, the statement in the reference is to the SEV-3 not the P-35. I'm no expert in this mark, & they do appear to be related, but they are not the same, so this doesn't really qualify as a suitable reference.

More importantly, as regards to the meaning of an 'elliptical' wing. It can be shown that if the lift distribution of a wing(s) varies elliptically from tip to tip, the down wash generated will be uniform & the induced drag will be minimised for the lift. I have my lecture notes as a source for this, but it isn't really appropriate as a wikipedia reference. From an aerodynamic perspective, it doesn't matter how this distribution is achieved. Therefore to claim that having a wing with curved leading & trailing edges is required in order to maximise aerodynamic efficiency is rather flawed. The fact is, the wing is elliptical so long as the shape (not size) of the cross section remains constant & the chord length (and hence local wing area & lift) varies elliptically from tip to tip. It doesn't matter if the leading, trailing or both edge(s) are curved, the wing will still be 'elliptical;' the term 'semi-elliptical' has no aerodynamic meaning (if you think about it, the spitfire doesn't have (geometrically) elliptical wings - they are in fact 2 semi-ellipse with different eccentricity, joined along the lateral axis - one of these semi-ellipses could just as well have an eccentricity of 1, i.e. a straight line segment). Similarly, the lift distribution could be achieved with constant cord, but having the wing twist at an appropriate rate from root to tip, so that the root is at a greater angle of attack than the tip. While this isn't an issue of planform, it is to an extent a feature of the wings' configuration & is certainly pertinent in the context of a claim of being "Aerodynamically the most efficient."

Another point to consider (though not directly relevant to this article) is that by having the wing twist down towards the tips - when the aircraft's angle of attach is increased, the root will have a higher angle of attach than the tip, so the roots will stall first, with the stall gradually spreading towards the tips - with the tips still developing lift, the aircraft will remain stable in roll. With an elliptical planform (& the necessary uniform angle of attach) the entire wing will stall at the same angle of attack, or in reality, one wing will stall entirely, slightly before the other, putting the aircraft into a spin. So while an elliptical wing might be "aerodynamically the most efficient," it isn't necessarily the best, so shouldn't be stated as such without qualification - this would be misleading. — Preceding unsigned comment added by 80.229.172.13 (talk) 15:22, 9 December 2011 (UTC)[reply]

You are missing the point - this isn't a lecture on how to acheive this, it is a listing of different recognized wing planforms, and both eliptical and semi-eliptical are recognized forms regardless of whether their effects can be acheived by other means. This isn't a matter of aerodynamic differences but of visual differences used for purposes of identifying a specific aircraft. In any case, lecture notes are a poor source not just because they are unpublished but because they often simplify things for the purposes of instruction, and while they are likely to follow best practices, those are usually the result of compromises that are not themselves covered in detail.
While a similar aerodynamic efficiency can be acheived with washout, it is still slightly less efficient since the drag of the extra outboard area is still present, and the weight from the extra area must be supported by greater structural weight inboard, decreasing the efficiency of the whole, hence the statement. Furthermore, washout is itself not without some cost when it comes to drag. The differences are not large but they are there, and in practice, straight leading edges are preferable from a manufacturing cost perspective and not because they can fully equal the improvement.
As for stalling across the span, this is commonly controlled by using different airfoil sections across the span and there is no reason it cannot still use washout. The Spitfire used a thinner section at the tip than the root (13% thickness at the root, 9.4% at the tip) and washout went from +2 degrees of incidence at the root to -1/2 degree at the tip. FWIW http://thoughtality.com/the-spitfire-wing has more info than you ever wanted to know about a real world eliptical wing (including that it wasn't 100% eliptical). NiD.29 (talk) 16:48, 9 December 2011 (UTC)[reply]
The DH.87 Hornet Moth may be the only aircraft to be built with both an (semi-)eliptical wing, and with a tapered wing, thanks to stalling problems with the eliptical wing. It bears some looking into as a useful case study - if only I could find some manuals giving the requisite numbers (the factory provided new wings to existing customers so the only difference was the wings).NiD.29 (talk) 05:24, 10 December 2011 (UTC)[reply]
"this isn't a lecture on how to acheive this, it is a listing of different recognized wing planforms" - exactly so. It gives physical descriptions, each with one or two illustrative factoids/links. That is all. — Cheers, Steelpillow (Talk) 10:27, 10 December 2011 (UTC)[reply]
So - I have reverted to my original, but added a note on the aerodynamic meaning. — Cheers, Steelpillow (Talk) 10:36, 10 December 2011 (UTC)[reply]

Straight wing with tapered tips

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While on the subject of wing planforms - does anyone know if a wing made up of a constant chord center section with tapered outer panels constitutes a less extreme variant on the compound taper or something different? It should be mentioned as a considerable number of aircraft used this planform in the late 30s and early 40s (T-6/Harvard, C-47, Lancaster, Avenger, Halifax, etc), even if it doesn't have a distinct name in the literature. Unfortunately all the books I have that mention planforms are either somewhat simplistic and mention only a few examples of different planforms before moving on, or they jump right into the calculations, covering all of the possibilities without explicitly naming them. Then there is the case of the Junkers 88 with three different leading edge sweepback angles, and two trailing edge angles. A simplified elipse as it were.NiD.29 (talk) 05:24, 10 December 2011 (UTC)[reply]

Good thought. If we can figure a name I'll illustrate it (needs a filename, ooer). "Straight wing with tapered tips" is the best I can think of off hand. Is there anything snappier in use? — Cheers, Steelpillow (Talk) 10:27, 10 December 2011 (UTC)[reply]
Wing stuck out on extensions is closer to the mark. Are these not convenient break points in construction rather than an attempt at some aerodynamic ideal. The Harvard's is parallel section is very short compared to the remaider of the span, the Halifax construced from sections, the Lancaster's wing interrupted by the long nacelles, the Avenger by the wingfold mechanism. GraemeLeggett (talk) 10:57, 10 December 2011 (UTC)[reply]
I think it is a combination of both - certainly the Harvard (and other Northrop derived wing designs) had a large element of structural simplicity rather than aerodynamics though there is a small benefit to extending the broadest chord part of the wing (possibly lost with the fairings and nacelles). I don't think the Avenger made much structural use of the kinks - certainly it wasn't necessary as the Wildcat with the same wing fold system didn't have them.
This is about the physical appearance in plan, not structure or dihedral. Nacelles are irrelevant. — Cheers, Steelpillow (Talk) 21:27, 10 December 2011 (UTC)[reply]

How does Modified tapered wing sound? NiD.29 (talk) 14:38, 10 December 2011 (UTC)[reply]

"Modified" could mean anything. One problem is that there is a continuum from wings with constant-chord main section and tapered tips to wings with a short constant-chord inner section and tapered main section such as the Harvard. I'm thinking more "Straight wing with tapered outer section" as perhaps the most common, e.g. Many Cessna types and several US military types through the 1930s and 40s. — Cheers, Steelpillow (Talk) 21:28, 10 December 2011 (UTC)[reply]

Time for a split?

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This article has grown larger than I expected, with shedloads of images to upload. Would it benefit from splitting into several smaller pages? For example the section on Wing planform is much the biggest and might easily be given its own page. What do you think? — Cheers, Steelpillow (Talk) 11:21, 14 April 2012 (UTC)[reply]

We do need at least a summary article on wing configuration. Would it be better to make this more of a "List of wing configurations" and then link to articles on each configuration? - Ahunt (talk) 11:48, 14 April 2012 (UTC)[reply]
I don't think it would split neatly at all; it might be better to trim individual sections slightly (or even reduce it to a list), and make better use of links and {{main}} &c. For instance, we already have a nice standalone article on dihedral; if explaining dihedral here, a second time, tends to make this article too long then there's an obvious solution. bobrayner (talk) 13:18, 14 April 2012 (UTC)[reply]
Is it expected to get any larger, I'd say it was more or less complete and not oversize. GraemeLeggett (talk) 13:38, 14 April 2012 (UTC)[reply]

My original intention was to classify and illustrate the significant wing configurations, and set them in context rather than just list them. Turned out to be more of them than I expected, and I added the idea of linking to at least one example of each, but I think the rest of the idea was good. So - a summary is hard because what do you leave out and how do you provide a hook to weird names that aren't obvious where they belong (such as rhomboidal)? And what angle do you take on it; structural, aerodynamic, planespotting? A list leaves you wondering why people built that stuff and did it work, it's just not informative. I don't see the few words here on dihedral as competing with the main article. And if some people think its current size is OK, then maybe that answers my question the easy way - it's not going to grow much any more. So, maybe there's no problem after all. — Cheers, Steelpillow (Talk) 20:40, 16 April 2012 (UTC)[reply]

Sounds like a reason to leave it as is! - Ahunt (talk) 23:50, 16 April 2012 (UTC)[reply]

Why I reverted recent edits wholesale

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Contrary to recent edits, the canard surface appeared as a stabiliser on the WWII Kyushu J7W and several of Rutan's postwar models such as the VariEze and many others. It is important to note that the "tandem triple" descriptions are modernisms and that historically the small surfaces were not though of as "wings" but ancillary surfaces for control and stabilisation: the "Canard" section is the wrong place for this. The tandem triple entry has also grown far too long. All this was stitched through by less drastic edits, which may be more easily restored or re-done individually than unpicked from the mass off stuff that needed reverting. — Cheers, Steelpillow (Talk) 20:32, 16 May 2012 (UTC)[reply]

==Stop vandalizing my edits == canards are never stabilizers period. — Preceding unsigned comment added by Stodieck (talkcontribs) 21:09, 16 May 2012‎

@Stodieck: That suggests the Wright Flyer had no stabilizer so no longitudinal stability. Dolphin (t) 22:29, 16 May 2012 (UTC)[reply]

That is correct. That is why the Wrights abandoned canards with the model B. The pilot had to constantly level the plane by adjusting the angle of the canard while flying the model A.

When they are stable, Canards are stabilized by the aft surfaces of the main wing. Think of the tailless Concorde, and put a canard on it. If the canard is small enough no problem. If the canard is too large the plane becomes unstable. --Stodieck (talk) 14:50, 17 May 2012 (UTC)[reply]

If my original edits are changed repeatedly and incorrectly, I will restore as often as necessary. "Never" is a strong word. Just because the Wright Flyer's canard did not provide stability, does not mean that none do. Check out the examples I gave, for a start. And it is not a case of using the wing to stabilise the canard, that's just linguistic games and logically back to front. It's a case of taking an unstable wing and adding a canard surface to stabilise the aircraft. An easy way to do this, though not often done, is to use the same airfoil section but increase the incidence of the canard. — Cheers, Steelpillow (Talk) 20:10, 17 May 2012 (UTC)[reply]
I would caution that we are not here to argue the truth, but verifiability, therefore it is reliably referenced material that is retained and unreferenced material that gets removed. - Ahunt (talk) 20:29, 17 May 2012 (UTC)[reply]

Thank you Mr. Hunt and I would like point out that my sources are the Wright brothers. And that Steelpillow cannot provide technical citations to the contrary. He can find articles that call canards stabilizers. Any article that explains how a horizontal stabilizer works also contains the evidence that canard wings are destabilizing. This has been pointed out by others in talk sessions with Steelpillow. If we cannot contain his edits, I will refrain from any other work in the Wiki. --Stodieck (talk) 05:56, 18 May 2012 (UTC)[reply]

By use of the word sources we mean in-line citations. (See WP:REFBEGIN.) Are you able to provide an in-line citation for a reliable, published source that quotes the Wright brothers and states their written comments on the matter? If we merely mention the name of someone held in high regard we might be doing nothing more than name dropping. On Wikipedia we want everything to be attributed to a reliable published source to allow independent verification. Dolphin (t) 07:31, 18 May 2012 (UTC)[reply]
Here is a link to one solid explanation of the Wright flyer development. See chapter 5 "RELATIVE STABILITY OF CANARD AND AFT TAIL CONFIGURATIONS". There are hundreds. http://www.wrightflyer.org/Papers/SETP01_Culick.pdf
Here is a snap shot of the Wright A, AB, and B. development. http://www.wright-brothers.org/Information_Desk/Just_the_Facts/Airplanes/Model%20_AB.htm --Stodieck (talk) 00:59, 20 May 2012 (UTC)[reply]
Thank you for those references. The second has no relevance here because it does not discuss stability, only controllability. In the first of them, Culick makes it clear that the main wing was intrinsically unstable (made worse by its high degree of camber), but that moving the CG further forward would have allowed the canard surface to stabilise the craft (something that the Wrights did not understand). To me, an additional surface that stabilises any craft is a "stabiliser", that's just the way our language works. — Cheers, Steelpillow (Talk) 11:27, 20 May 2012 (UTC)[reply]
User:Dolphin51 has well summed up the crux of the matter. Name-dropping doesn't count, we need citable references that can be used. I would also add that the Wright brothers were very early in the history of aircraft development and many things have changed since their time, so even if they stated in 1908 that canards are never stabilizers it doesn't mean that other later designers didn't prove them wrong. The opinions of editors are not relevant here, it all comes down to references that can be cited. If the refs conflict or disagree then we don't pick and choose, we quote both and note their disagreement. - Ahunt (talk) 11:20, 18 May 2012 (UTC)[reply]
Here are a couple of web pages explaining how to achieve stability using a canard foreplane: http://www.desktop.aero/appliedaero/configuration/canardstability.html and http://adamone.rchomepage.com/cg_canard.htm . Yet here too is a forum conversation discussing the view that all canards are inherently unstable: http://www.airliners.net/aviation-forums/tech_ops/read.main/12722/ . Clearly, with college lecturers apparently telling students one thing and (possibly un-citeable) engineering descriptions explaining how to achieve the exact opposite, we have a potential clash between truth and verifiability. My own view is that this math has to exist in some text book somewhere, I just don't personally know where to look. It is doubly frustrating for me because I recall published discussions of the stability of various canard types, but had to clear out my copies when I moved house. Consequently I believe the current case for the truth of stability to be stronger than the current case for verifiability of instability, mainly because I expect it to solidify over time. Y'all may beg to differ, however I would ask you not to be dogmatic that canards can never be stable just because the Wright Brothers couldn't figure it out. Or, are those engineering descriptions suitable for citation after all? — Cheers, Steelpillow (Talk) 11:36, 19 May 2012 (UTC)[reply]
And here's a link which explicityly states that "Some airplanes ... get their stability from a much smaller wing (called a canard) in the front." http://www.av8n.com/how/htm/aoastab.html#sec-canard-same — Cheers, Steelpillow (Talk) 12:19, 19 May 2012 (UTC)[reply]
And at http://www.centennialofflight.gov/essay/Theories_of_Flight/Stability_II/TH27.htm, "The North American XB-70 has a pair of canards for stability at supersonic speeds to prevent tuck under." Can we lay this instability canard [sic] to rest yet? — Cheers, Steelpillow (Talk) 12:35, 19 May 2012 (UTC)[reply]

"how to achieve stability using a canard foreplane: http://www.desktop.aero/appliedaero/configuration/canardstability.html and http://adamone.rchomepage.com/cg_canard.htm" If you work through these you will find that the secret to making stable "canard aircraft" is keeping the size of the "canard winglets" small enough to prevent them from destabilizing the whole "canard aircraft". I.e. passive "canard winglets" are alway destabilizing, "canard aircraft" are clearly not always unstable.

Canards winglets can be used as pitch control element for active stabilizer system. They not desirable from a reliability perspective. (Works just fine if you don't mind dying everytime the computer crashes.)

The problem with the term "canard" is that it is almost universally used without specifying whether we are referring to an aircraft configuration or a fin. As editors of the wikipedia I strongly suggest that we never allow the word canard to used without a qualifier; canard winglet, canard fin, canard aircraft, or canard configuration. This alias is deadly. "Small forward wing" helps reduce confusion about the fin type of "canard".

I am not being dogmatic about saying that "canards can never be stable", In fact I have never said this at all. I said that "canards" (intending to say small forward wings) are never stabilizers. That is to say, that, per se, they never add to the stability of an aircraft.

"Some airplanes ... get their stability from a much smaller wing (called a canard) in the front." http://www.av8n.com/how/htm/aoastab.html#sec-canard-same — This amateur author does not actually analyze stability. I would put this under self published references.

And at http://www.centennialofflight.gov/essay/Theories_of_Flight/Stability_II/TH27.htm, "The North American XB-70 has a pair of canards for stability at supersonic speeds to prevent tuck under." This is a caption under a picture, not an encyclopedic reference. This statement is simply inacurate and suggests that tuck under is an instability. I believe that tuck under is quite stable, it is not an instability in the sense of this disscusion.

The theory of how horizontal stabilizers work has been known literally since the Wright brothers. It has been taught to millions as part of standard pilot training curriculum since that time. It is included in every book on aeronautics. There are 1000s of references. I would guess that there are a half million people in the US alone who understand, technically, why arrows don't have feathers on the front.

By reverting "edits wholesale" you have also discarded completely new material unrelated to this topic that came from myself and others. You didn't notice, because you did not look. This is straight forward "wholesale" vandalism.

--Stodieck (talk) 17:34, 19 May 2012 (UTC)[reply]

OK, I have now restored much of NID.29's edits - sorry about that. Yeah, I did notice but it was more practical to do it this way round - I didn't agree 100% with all of them, and wanted to be selective. — Cheers, Steelpillow (Talk) 18:51, 19 May 2012 (UTC)[reply]

Now restore the 3-surface entries. You can't agree or disagree with material you have never seen before, and don't understand. And that is not sufficient criteria for removal in any case. --Stodieck (talk) 19:08, 19 May 2012 (UTC)[reply]

@Stodieck. Thank you for the reference to Culick. It is a fascinating article and I intend to read it more thoroughly in coming days. On page 14 it states:

Hence the neutral point for a conventional configuration lies aft of the wing’s aerodynamic center but the neutral point of a canard lies forward. That is the explicit realization of Bryan and Williams’ conclusion that the aft tail configuration is relatively more stable than the canard [if] the same surfaces are used. The more forward is the neutral point, the more difficult it is in practice to get a stable aircraft: the natural tendency during design and construction of an aircraft is for the cg to lie further aft than desirable.

This tells the reader that the canard configuration has a neutral point; and that the tail configuration is more stable than the canard (other things remaining unchanged.) So the canard configuration is not intrinsically unstable, according to Culick. By diligent design and suitable placement of the center of gravity a stable aircraft can be built and operated. However, Culick concedes that it is more difficult to design a canard configuration that is both stable and efficient to operate - the neutral point is forward of the aerodynamic center and as the neutral point moves in that direction the payload must be reduced if the lifting load on the canard is not to become excessive.
I agree that it is easier to design and operate a commercially viable airplane using the conventional aft tail configuration than it is to design and operate one with the canard configuration. However, this is very different to implying that canards are intrinsically unstable, or that a canard cannot be considered to contribute to longitudinal stability, or that a canard cannot be considered to be a stabilizer.
I am unaware of any airplane in the canard configuration with a straight main wing that has been demonstrated to be longitudinally stable, but then I haven't gone looking. For the sake of having a fruitful discussion, let's assume no canard with a straight main wing has been built and shown to be longitudinally stable. That no such aircraft has yet been built does not permit Wikipedia to imply that the canard configuration is intrinsically unstable, or that a canard cannot be considered to be a stabilizer. Dolphin (t) 12:40, 20 May 2012 (UTC)[reply]
I thought I would be able to convince myself and others that a canard surface can contribute to the longitudinal stability of an aircraft but, so far, I haven't been able to do so. Perhaps Stodieck and Steelpillow are both well ahead of me when they consider that a canard, in isolation, doesn't contribute to longitudinal stability. All that can be said is that the canard configuration can be longitudinally stable providing the CG is forward of the neutral point. Stability is provided by the CG being so far forward of the aerodynamic center, not by the canard. Dolphin (t) 04:28, 21 May 2012 (UTC)[reply]

Proposed strategy

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Having slept on the problem, I'd suggest there are two distinct points of view here:

  • In common language, any additional surface that stabilises an otherwise unstable craft may be called a "stabiliser".
  • Technically, analysis of the dynamic interaction between fixed fore and aft surfaces treats the action of the forward surface as destabilising and the action of the aft surface as stabilising, irrespective of the relative size of the surfaces.

[Update] Or, to put it another way, there is a difference between the design purpose of a feature and the technical mechanism which delivers the outcome. Both are valid on their own terms.

While Wikipedia undeniably aims to be a reference work, such works can have different scope. A text book may give a word a precise technical meaning, while a dictionary might record several different usages of the word in different contexts. A general encyclopedia such as this one will explain the more notable usages defined in the dictionary or, as we put it, respect different points of view.

So, does respect for both points of view here represent a reasonable strategy? — Cheers, Steelpillow (Talk) 12:20, 20 May 2012 (UTC)[reply]

@Steelpillow: In your second bullet above, you concede that fixed fore surfaces are destabilising. I don't agree that such a concession is necessary. Stodieck has provided a reference to a paper by Culick and that paper correctly shows that a canard configuration has a neutral point. When the CG of the aircraft is at the neutral point the longitudinal stability is neutral; and when the CG is forward of the neutral point the longitudinal stability is positive. It may be a popular view that fixed forward surfaces are intrinsically destabilising but such a view would not be compatible with a sound technical analysis. Dolphin (t) 12:49, 20 May 2012 (UTC)[reply]
I'll try to clarify. Considering the canard surface independently from the main wing, as its angle of attack increases so too does its lifting moment ahead of the CG: this action is intrinsically destabilising and needs to be counteracted within the overall design by its contrived relation to the increase in lift from the main wing. [Edit] If the main wing is also inherently unstable, the smaller canard surface is in practice introduced in order to stabilise the craft. This is why I see two different points of view, depending on whether we consider the action of the canard in isolation or as a part of the overall design. Stodieck seems to instinctively assume the former, you and I the latter. Any clearer? — Cheers, Steelpillow (Talk) 13:25, 20 May 2012 (UTC)[reply]
I've been observing. My essential take on the matter is: if you build a canard design aircraft (insofar as its got some sort of airfoil sticking out either side of the nose) it will (if you get your calculations) right fly like a bird or (if you forget to carry the one) possess the aerobatic grace of a breeze block. Considering a single element in absence of other factors is only a start, at some point the aircraft must be considered as a whole. The reasons for choosing a canard could be manifold - eg better visibility but in all cases it either flies according to the designer's desires or doesn't. GraemeLeggett (talk) 16:44, 20 May 2012 (UTC)[reply]
I don't recall anyone saying that canard aircraft are intrinsically unstable, the statement was that canard winglets are intrinsically destablizing thus properly called "canard" wings, not tailplanes or horizontal stabilizers. The Wrights did call them stabilizers, because canard aircraft are more stable than straight wings!! It has been awhile since that option has been under consideration. But all of the Wrights early designs were stabilized by the pilot, the canard provided only pitch control. --Stodieck (talk) 20:12, 20 May 2012 (UTC)[reply]
@Stodieck: Culick makes the point that the Wright Flyer was longitudinally unstable simply because its center of gravity was behind the neutral point, not because it was in the canard configuration. When the CG is behind the neutral point the destabilising influence of the main wing exceeds the stabilising influence of the canard. I see nothing in Culick to indicate the canard should not be described as a stabiliser. Dolphin (t) 22:49, 20 May 2012 (UTC)[reply]
@Dolphin. Try writing down the pitch stability equation for small perturbations from trim, in the linear range. It is immediately apparent even for this simple model that something's gotta give. Typically if you let the plane sort itself out it will head towards a nose up or nose down stable point, out of the linear range, not straight and level. Sure the pilot can continually adjust the elevator to maintain S&L, but that is not stability, that is instability. Windtunnel experience for the Curtiss XP55 appears to bear this out. If you make the front wing 'bad' enough, yes it will saturate and help to limit the excesses seen in pitch, but that's like saying hopping is better than running because you only wear one shoe out. Greglocock (talk) 09:11, 14 June 2012 (UTC)[reply]
@Greglocock: My current position is shown in this diff. Dolphin (t) 11:28, 14 June 2012 (UTC)[reply]

Reread the paragraph above your last paragraph, starting with "I don't recall anyone saying that canard aircraft are intrinsically unstable". Your attacking a statement that has not been made. Also, neither my version, nor Steelpillow's reversion of the Canard entry under "horizontal stabilizers" describes canard winglets as stabilizers. Please difference the revision history before and after the "wholesale revision of edits" to see what was actually changed. This discussion has gotten lost. Turn your attention to the inclusion of 3lsc aircraft that was also deleted by Steelpillow in this edit. --208.74.180.13 (talk) 00:25, 21 May 2012 (UTC)[reply]

I suspect I see things a bit differently:
There are three possible states regarding stability -
  1. positive stability - attitude changes are self-correcting, causing the aircraft to resume the same attitude (within reason).
  2. neutral stability - changes result in a new stable state, but at a new attitude and with no tendency to return to the original attitude.
  3. negative stability - attitude changes force greater divergent changes in attitude unless manually corrected.
Any aerodynamic device that allows the aircraft to achieve either positive or neutral pitch stability is by definition a stabilizer.
Not all canards have negative pitch stability (some do, some don't - it's a design issue).
Likewise, some conventional aircraft have had negative pitch stability.
If not all stabilizers act as such, perhaps a different word is called for - like horizontal tail or supplemental flying/lifting surfaces?NiD.29 (talk) 05:29, 21 May 2012 (UTC)[reply]

"Not all canards have negative pitch stability (some do, some don't - it's a design issue" - You are referring to canard aircraft, canard winglets are always destabilizing. If the center of gravity moves forward after the addition of canard winglets, the main wing becomes a stabilizer. The canard winglets are just a lifting wing, never a stabilizer. This is what the deleted text stated. --Stodieck (talk) 15:21, 21 May 2012 (UTC)[reply]

I am (not very) astonished to see what is a relatively technical discussion supposedly aided by references to captions on photos. From a control viewpoint a lightly loaded forward horizontal surface would have to have a lift gain in pitch significantly less (due to pitching moment, and the drag of the little wing, which is destabilising in its own right) than that of the main wing in response to small perturbations in AoA from a trimmed condition, in the linear range. This is rather unlikely in a passive system, to put it mildly. I'd have thought a search of the LARC/NACA/NASA archives would be more productive than random hits on blogs. NACA 941 and NASA X 823 are a good starting point. The Culick paper is also fine, presumably the editor denigrating it didn't bother to read it, as it discusses the history of the issue, not just Wright's understanding. Greglocock (talk) 02:13, 14 June 2012 (UTC)[reply]

3 surfaces

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One of my contributions eliminated by this wholesale reversion was the inclusion of "3 lifting surface" and "three surface" aircraft. I have done some googling on the prevalence of these terms and the terms used instead in the current "horizontal stabilizer" section of the Wikipedia article.

"tandem triple" aircraft 7,220 hits (Wikipedia leads the way)

"3 lifting surface" aircraft 10,600,000 hits

"three surface" aircraft 63,900 hits

"triplet" aircraft produces millions of hits, none of which seem to refer to actual aircraft

It is very clear, from the number of hits on valid citations within these searches that the aircraft design establishment usually uses "3 lifting surface" or 3lsc first, followed by "three surface" aircraft. Neither triplet nor tandem triplet have significant usage. I suggest that the terms 3 lifting surface", 3lsc, and "three surface" replace "tandem triple" and "triplet". "Tandem triple" is quite suspicious since the wing configuration diagram it refers to is not a tandem.

The following article may be of interest here. [Who Fooled Wikipedia]

Relevant citations would be good, since there appear to be so many sources to choose from. Also, you need to make sure that all such types do have three lifting surfaces, not any surfaces which contribute merely to stability and/or control. We wouldn't want to misuse the word "lifting". — Cheers, Steelpillow (Talk) 20:21, 21 May 2012 (UTC)[reply]
[Update] I think this entry is too long as it is. Stodieck has now restored some bits that I trimmed, presumably for reasons explained here. I intend to trim more, including most likely including some bits that I wrote. Once clear references to use of the term "lifting" are found, I'd suggest that the best place to write it all up would be a new page for this topic. Meanwhile, does anybody else have a view on whether trimming the entry in this article would be good or bad? — Cheers, Steelpillow (Talk) 21:43, 23 May 2012 (UTC)[reply]

OK, so I edited back the scope because there are so many reasons put forward for this configuration. That kind of suggests it needs its own article, too. Then I thought to check those search hits quoted above, and Google found:

  • "tandem triple" aircraft 7,690, and "tandem triple" wing 7,240
  • "3 lifting surface" aircraft 8,550 hits and "3 lifting surface" wing 7,860
  • "three surface" aircraft 20,900 hits and "three surface" wing 54,900
  • "triplet" aircraft - noting significant, but then this choice above was probably due to missing that it was intended to be taken as tandem triplet, as in the admittedly ambiguous tandem triple or triplet, before that got changed in subsequent editing.

So then I also tried:

  • "tandem triplet" aircraft 817 and "tandem triplet" wing 23,500
  • "triple tandem" aircraft 24,100 and "triple tandem" wing 19,300

I find the differences remarkable: even searching on "3 lifting surface" alone gave just 11,700 hits, so I do wonder which search engine found over ten million, or whether perhaps that was a typing error? One trusts that the Who Fooled Wikipedia link below it was posted in good faith. ;-)

Anyway, it is not clear which is the winner here so some careful digging for reliable references is going to be needed. — Cheers, Steelpillow (Talk) 21:16, 25 May 2012 (UTC)[reply]

"3 lifting surface" aircraft 10,600,000 hits is what happens when google removes the quotes and one fails to notice. --Stodieck (talk) 00:53, 1 June 2012 (UTC)[reply]

It may be a dead issue but on road vehicles a pair of axles are referred to as a tandem, but a group of three is a tridem. Not sure if this has been used in the aviation world but it is more succinct and less of a mouthful.NiD.29 (talk) 19:11, 15 July 2012 (UTC)[reply]

slip wing

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Am I alone in thinking the slip wing (as per the Hillson Slip-wing Hurricane & Bi-mono) should be listed? It took off as a biplane and then jetisoned the top wing to continue as a monoplane so as to increase the possible takeoff weight...NiD.29 (talk) 23:31, 16 May 2012 (UTC)[reply]

Sounds reasonable to include it, to me. - Ahunt (talk) 23:33, 16 May 2012 (UTC)[reply]
I treated the slip wing as a composite aircraft because the bits come apart in flight, unlike the Nikitin-Shevchenko IS which stays in one piece. Feel free to expand that article :) [Edit: Oops, either I didn't or someone reverted. But that's where I planned to describe it.] — Cheers, Steelpillow (Talk) 20:30, 17 May 2012 (UTC)[reply]
Composite aircraft allow the individual components to continue flying independantly - OTOH the top wing of the slip wing would have glided/crashed to the ground after release and lacked any controls (no ailerons, flaps or even a vertical stabilizer) - not the same as the Pemberton Billing "slip wing" which were just another name for a parasite aircraft - though perhaps parasite aircraft should be mentioned as well together with the slip wing.NiD.29 (talk) 21:24, 17 May 2012 (UTC)[reply]
You appear to know more about slip wings than I do. From what you say, I guess some designs might be best understood as composites while others might not. However I'd be willing to bet there's no definitive authority out there. Also, my understanding is that the Hurricane type was never more than a proposal. That makes it hard to judge whether to include it here - is it a composite, is it notable enough anyway? I think I'd prefer to wait until Wikipedia's treatment of the subject is more mature - either of the various designs or maybe an article on the Slip wing. If others feel strongly, I won't stop you adding it [Update] to this article. — Cheers, Steelpillow ([[User Talk:Steelpillow|Talk]) 10:43, 19 May 2012 (UTC)[reply]
Done - though a picture might be nice - is whoever did the others still around? :) NiD.29 (talk) 13:32, 21 May 2012 (UTC)[reply]
 :-) Give me a nudge in a week or so if it hasn't appeared by then. — Cheers, Steelpillow (Talk) 20:27, 21 May 2012 (UTC)[reply]
OK, done it. Any good? — Cheers, Steelpillow (Talk) 12:51, 26 May 2012 (UTC)[reply]
Looks like it is being raised - perhaps a double graphic showing that it is no longer attached or increase the height so the bottoms of the wings struts are more clearly parted from the lower portion? NiD.29 (talk) 16:59, 26 May 2012 (UTC)[reply]
Yeah, it does a bit, that was why I asked. A double graphic makes it a different kind of drawing from the rest so I'd prefer to avoid that, at least in this article - I have one more idea, but can't do it right now, it's my bed time over here. Keep an eye out. — Cheers, Steelpillow (Talk) 21:09, 26 May 2012 (UTC)[reply]
Any better this way round? If not, I'll have to try skewing the slip wing as it lifts off, or something. — Cheers, Steelpillow (Talk) 20:06, 30 May 2012 (UTC)[reply]
While on the subject of drawings - the asymetrical (Blohm & Voss) drawing should show the same amount of wing on either side of the tail boom - the crew pod was inserted into the gap caused by the outboard portion of that wing being moved out. - like thus:
    ____
-----||--||---
==---||--||-==
     ||  
  ===||

I had the airfix kit when I was a kid, and I removed the pod and reattached the wing parts to convert it into a normal aircraft.NiD.29 (talk) 20:29, 27 May 2012 (UTC)[reply]

Not really significant, as these drawings are meant to be generic, but no harm if it helps. Any better now? — Cheers, Steelpillow (Talk) 20:06, 30 May 2012 (UTC)[reply]
Perfect on both - thanks! BTW do you do the svgs by hand or do you use a program? NiD.29 (talk) 01:23, 31 May 2012 (UTC)[reply]
Just hand-edited in Inkscape. I usually copy a similar drawing and edit that, rather than start from scratch each time. The first few took a while but nowadays it's pretty quick. The 3D views are the biggest challenge, and it is here I rely most on my training in traditional draughtsmanship. — Cheers, Steelpillow (Talk) 19:54, 1 June 2012 (UTC)[reply]

Why You reverted recent edits wholesale?

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Revert to last good edit? You reverted a whole series of good edits. I can't use the words I'd like to use for that insulting unwarranted, WP:OWN-ish comment (and the reverts).
The edits I made fixed a slew of egregous errors and replaced poor examples with better ones - you didn't even have the decency to check if the changes were warranted.

Many of the examples are obvious only to specialists in violation of wiki policy, rather than those that might be familiar to non-specialists visiting this page - such as the Cessna (150, 172 etc) versus the P-80 which most Americans wouldn't even recognize anymore and the EE Lightning (which is a special case not otherwise covered as it is a type of cropped delta - or so I have read) vs. one of the many Boeings or Airbuses - or indeed any of the long list of aircraft that would make better examples.
Etc etc...

A sesquiplane is defined by wing area - not span. It applies to aircraft with either reduced span or chord as per any reputable source you may deign to check such as (Gunston, Bill, The Cambridge Aerospace Dictionary Cambridge, Cambridge University Press, 2004, ISBN 978-0-521-84140-5, page.552) which says - "Biplane whose lower wing has less than half the area of the upper." (bolding mine)
The F-111 was hardly the first military swing wing - the Grumman XF10F Jaguar beat it into the air by 15 years.
Saying the Crusader lifts the leading edge is misleading - it rotates the whole wing, causing the leading edge to raise. The difference is that leading edge devices of some sort are allowed for in the original statement when it is really just rotating about its rear wing spar.
Etc etc...
Excellent work on the drawings but you need to let others make substantive improvements to the text.NiD.29 (talk) 18:31, 26 May 2012 (UTC)[reply]

Hi. By last good edit, I meant the last one before the first bad edit. I was in a hurry for reasons that should have become clear from the intervening discussion, and it is hard to explain every nuance in a quick off-the cuff one-liner, but if I gave the wrong impression I can only apologise. The next thing I did was explain, as above, that I knew I was reverting some good edits but it was going to be easier to restore the good stuff selectively than revert the bad selectively. Then, as soon as I found the time I went on to restore the sesquiplane and crusader edits, and other bits, so I'm not sure what the problem with these is now or where that asserts ownership or "lacks the decency to check". [Update] No - somebody else did that while I was writing this. Anyway, I meant to. This is getting complicated. I know I did restore some bits, just not these. Happy to see them back.
I am conscious of Wikipedia's global readership, so what any particular national group finds familiar cuts no ice. Rather, where I can I put up an example that is most notable - say first or famous. But if I don't know any better I may just put up what springs to mind - and yes, that is more likely to be British - and if someone else does the same, I see no value in fighting over two bad examples, so I didn't bother to restore those - you are welcome to if it means that much to you, but I would hope that you too can focus on international notability. For example re. the Jaguar, I don't see it as notable - the Bell X-5 beat it as the first to do it in the air and the F-111 beat it into production: either of those is more notable. Do we need a discussion about what is most notable?
It may be that I have missed the odd genuinely improving edit? If so, then I apologise again and will be glad to restore it, but I am not currently aware of any: I'll check again when I can, or else let me know. — Cheers, Steelpillow (Talk) 21:05, 26 May 2012 (UTC)[reply]
Thanks - and apologies in return! I realize now that the edits before mine were a problem and mine just got in the way (hence the comment). Always a difficult thing to fix.
The F-111 is notable but not first, and if adjectives must be used the claims are void - but are usually overlooked by the hoi-polloi so I prefer to remove them rather than elaborate unless it is important to the discussion at hand - 91 people crossed the Atlantic before Lindbergh - and no one knows how many people flew before the Wrights - they just have a string of adjectives for very specific claims - but they were first. First & always should rarely be used about aviation as false claims abound, particularly from fanbois & their governments and though that hasn't the case here, it can't hurt to eliminate unneccesary contention.
Many of my changes were to include more countries - The EE Lightning is a relatively minor type outside the UK which was why I tried changing it to the widely used Hunter, although others would suit. I skipped the Sabre as there are too many US examples anyway, particularly for configurations with few choices. It was a toss-up between the MiG-15 and the Hunter (trying to keep to widely known early swept wing jets).
Cheers!NiD.29 (talk) 22:28, 26 May 2012 (UTC)[reply]

IPs don't require permission to "be bold". Nobody does.

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Steelpillow, you said to "discuss first", but the be bold edict specifically contradicts this. No editor is ever required to discuss an edit before making it, particularly not IP's. No one needs to get permission from anybody. Ahunt, you reactively declared my edits "unhelpful", apparently with little actual examination of them, and you tried to enforce Steelpillow's admonishment to discuss by artificially creating the first steps toward an edit war. You both have behaved in a way that suggests you feel like you own the article, or at least are reactively biased against IP edits.

I've found there's not much anybody can do about this. If one or two editors want to own an obscure article they can, even though it is against WP policy. I made one last attempt to improve the section. I integrated polyhedral, and made a few formatting improvements (like scooting the channel-wing diagram below it's description). I retained the removal of those two off-topic inline citations to "cranked arrow". I simplified the "do not confuse with cranked arrow planform" message in a way that (I think) doesn't actually add to the confusion like (I think) the previous wording did.

If you want to summary revert that too, you probably can, but I don't recommend it. Instead, please carefully review it, and edit your improvements into it. It really is better than it was before, and you can make it even better by adding your perspective to it, rather than just naysaying.

108.7.243.154 (talk) 17:24, 30 June 2012 (UTC)[reply]

To summarise from WP:BOLD: Be bold ... but ... not too bold. I would also draw your attention to the start of the third paragraph, which is in bold (sic) type: Don't get upset if your bold edits get deleted. Your edits were also ungrammatical, the inclusion of "polyhedral" in the title adds unnecessary complexity, and those references you removed relate to other uses of the term "cranked" - which is why they are useful here. Maybe there was something worth keeping in your edits, but the noise was just too loud for us to put up with - especially as your style of community engagement is hauntingly familiar - failing to take in what you read, restore your own POV then talk afterwards, aggressive and rude style of discussion - shall I ask an admin to check if you are using your IP as a WP:SOCKPUPPET? — Cheers, Steelpillow (Talk)
OK, so I take to heart your point about not reverting the good bits. As sometimes happens it is easier to revert the lot and then restore the good bits, so that is what I have done here - polyhedral is back in the text, and the channel wing dropped down. I still left "polyhedral" out of the title since it is a composite of dihedral and anhedral, which are mentioned.
Meanwhile, I would like to observe that you have a good grasp of the design technicalities, which is all too rare among us editors. But your community engagement is less mature. Where I offer you links to aspects of WP:POLICY, I do that in a spirit of helping you into our community, not of points-scoring. WP:GOODFAITH cuts both ways. For example I assume that your use of IP sockpuppetry is in ignorance of the dire consequences it can bring upon you, so I do not report it, merely advise you of it. I do hope that you can read, mark and inwardly digest, as they say. — Cheers, Steelpillow (Talk) 18:17, 30 June 2012 (UTC)[reply]
I have also taken another look at the treatment of the term "cranked". The problem that several of us ran into is that the world has got in a mess. The term appears widely used to mean different things - as evidenced by the varied citations. It seemed most useful to bring some clarity to Wikipedia by using the term fairly narrowly, but at the same time acknowledging those other usages. The current form is effectively what I came up with, to accommodate those pressures. I for one would be happier if a cleaner explanation could be found, but it would not be helpful to lose those references or the explanation they support. Hence the request to discuss such changes here. — Cheers, Steelpillow (Talk) 20:49, 30 June 2012 (UTC)[reply]
If you check the article history for my own contributions, you will see that I have hardly ever edited this article, so claiming that I think I own it is not really supported by the facts. I don't have anything here to defend except the overall quality of the article. I reverted your edit and noted it as unhelpful as it made the article less comprehensible, not better, and you seemed determined to insert it regardless of disagreement. Under WP:BRD the correct prceedure is to make an edit and then, if it gets reverted, discuss on the talk page to come up with a consensus as to whether the proposed changes should be included, some part of them should be included or not. Accusing other editors of malice and not having read your edits is not assuming good faith and doesn't help make your case that your proposed changes should be included. - Ahunt (talk) 18:20, 30 June 2012 (UTC)[reply]


Ahunt, sorry if I swept you up in implying you were attempting to own the article. Nobody really has the time to review past histories, only the time to assess the recent edit. The apparent tag-team effort did me give that impression. Your "unhelpful" remark in your reversion edit summary did contribute strongly to my perception that you did not assume good faith.

Steelpillow, yes it is sometimes easier to revert. I've done it in the past, but I've found that it's important to be really really nice about it.

But, I have more to do in my life than to get muddy in fights like this. You win. I won't touch this page again.

Yours, 108.7.243.154 (talk) 00:32, 1 July 2012 (UTC)[reply]

It is not a question of "who wins" - the aim is to build an encyclopedic here. - Ahunt (talk) 10:31, 1 July 2012 (UTC)[reply]

Missing wing configuration types?

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I'd add the Rogallo wing, that is some kind of a Delta wing, but soft; as example of Circular wing, the American Nemuth Parasol; as a Semicircular wing, the Arup's flying wings and the Navy's Flying Pancake; as an unclassifiable or inverted Delta, the straight part as leading edge (It would be good having specific professional comments about the advantages, disadvantages and performances of the Inverted Delta), the 1934 design of Raoul J. Hoffman (Popular Aviation, March 1935, pp 163 and 196), and also one of the Fauvel flying wings, the AV-10; in YouTube, linked to the Arup airplanes' films, some other low aspect ratio Inverted Delta-like wings appear. There was another example of Annular wing, similar to the French Coleoptere and to 1906 Louis Bleriot's 'Bleriot III' that Bleriot designed for water takeoff and landing; this Annular wing toy airplane had an ordinary chord and conventional tail surfaces, it was proposed in the April 1963 issue of Popular Mechanics to be built by hobbyists. The July 1964 Issue of Popular Mechanics features a Pancake or Parasol wing model airplane. The 1909 French airplane Givaudan had tandem round wings. The first variable swept wing jet airplane was the Messerchmitt P.1101, that inspired the early USA designs, however, the first attempts were unstable, and the problem was not solved until a short, fixed high swept back section was added to the root of wings. The Burnelli's lifting fuselages can be considered another special type of wing? Some data exist about fully flying disc shaped aircraft, as in Popular Mechanics Jan 1995 and Nov 2000.--Jgrosay (talk) 18:31, 20 April 2013 (UTC)[reply]

That's quite a list! Some are just a combination of two features - the Rogallo a flexible tailless delta, the Givaudan a tandem annular. There are so many combinations that I don't think there is much point in trying to list ing them; just a few, such as the tailless delta, seem important enough to mention. I would describe the Arup wing as semi-elliptical (similar to the Seversky P-35 but with lower aspect ratio). ISTR that the Messerschmitt never transitioned in flight, that was left to the Bell X-5 derived from it. The Burnellis, like the Northrop X-216H, are difficult to classify: they are sometimes called flying wings, yet they do not conform to the usual definition because they have twin tailbooms and a tailplane. I am kind of on a WP:wikibreak for a while (just dropped by to add my thoughts), so make of that what you will. — Cheers, Steelpillow (Talk) 19:10, 21 October 2012 (UTC)[reply]

Flying saucers

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The book "German Jet Genesis", by David Masters, Jane's 1982, ISBN 0 7106 0186 7, includes drawings of three German flying disks designs from the last months of WWII: the Miethe, the Habermohl and the Schriever; other sources say that the Schriever reached the flight stage, going well above the speed of sound, but was deliberately destroyed before falling in the hands of the allies. It was said also that Schriever, that after the war relocated in Austria, offered to build again a copy of his saucer for a very low cost, but found no support. The March 1956 issue of "Mechanix Illustrated" -MI- has in the cover a drawing of an U.S. Air Force Flying Saucer Project, and in pp 78-81, the inherent technology in it, mainly jet engines, thrust control and Coanda effect for handling. From where or what they had the idea of building a thing so shaped remains unknown to me. In 1964, Popular Mechanics -PM- published an article about the research conducted by major Seversky on a flying machine, round in shape and with a wire structure close to the one in an umbrella, supposed to fly on the principle of conservation of momentum by sending down a flow of ionized air, idea that failed because the inherent physics never reaching a sufficient degree of efficacy in transforming electrical power into lift; the November 1964 PM issue -Spanish edition- containing this flying object also included an article on air pollution that, in addition of describing the California "Chemical Smogs", warned against the global warming effects of the continuously increasing concentration of atmospheric CO2 due to mankind's activities, from 290 ppm in 1890 to 315 ppm then. In the Moller website and in YouTube, you can see a USA prototype of flying disc apparently using the basis depicted in MI-March 1956, hardly achieving a several feet height uncontrollabe hovering over the ground.--Jgrosay (talk) 21:15, 21 October 2012 (UTC)[reply]

All fascinating but not reliably referenced. If a German designer had credibly claimed supersonic flight during the immediate postwar era, I am sure the Allies would have tumbled over themselves to grab him, as they forcibly grabbed so many others - his claim must have looked really shaky to have been ignored. The ME articles date from an era when the US authorities positively encouraged flying saucer (and alien encounter) stories, in order to distract attention from real "black" projects: so for me at least, the standard of verification there has to be especially good. The Avro Canada VZ-9 Avrocar was funded by a U.S. agency - perhaps that is the wobbly saucer in the videos? I came across one of the first computer-based predictions of global warming ca. 1975, yes it's tragic that we have known for so long but our leaders have done next to nothing about it. — Cheers, Steelpillow (Talk) 11:41, 10 April 2013 (UTC)[reply]

Tailplanes and foreplanes

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Canard : the Saab Viggen canard provides lift and pitch control; it is a destabilizing surface.

Tandem : both wings provide lift (like a lifting canard); the front wing is destabilizing like a canard, the aft wing IS the stabiliser (like a taiplane).Plxdesi2 (talk) 21:53, 9 April 2013 (UTC)[reply]

From "Proposed strategy" :
"When the CG is behind the neutral point the destabilising influence of the main wing exceeds the stabilising influence of the canard. I see nothing in Culick to indicate the canard should not be described as a stabiliser". Dolphin (t) 22:49, 20 May 2012 (UTC)[reply]

@Dolphin. Longitudinal stability of a canard (or tandem) aircraft asks for : 1) Longitudinal balance, that is the negative pitch moment of the main (aft) wing has to be equal and opposite to the positive pitch moment of the foreplane. 2) The derivative dCm/da must be negative, that is if "a" increases, the foreplane positive Cm increase has to be lower than the negative main wing Cm increase. In case of pitch instability, to provide dCm/da more negative, one can increase the weight/area ratio of the foreplane by adding a front weight (as Wright brothers did) or decreasing the foreplane area. With a fixed CG position, the foreplane area increase moves the neutral point forward (doing like a backward CG shift) and decreases the pitch stability > the foreplane is a destabilizing surface and, conversely, a tail plane (or an aft wing) is a stabilizing surface. Dolphin sentence seems to be a mix of balance and stability considerations. Plxdesi2 (talk) 08:13, 10 April 2013 (UTC)[reply]

Saab Viggen, lifting canard

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@Steelpillow. "no need to mention "lift" twice (also, the Viggen predates modern analysis).

I wrote "This model introduced the use of a close-coupled lifting canard to increase lift and pitch control" because this canard is a lifting surface in cruise, different from a control canard, non lifting in cruise but adding some lift at high incidence angles (Rafale fighter, for example). Although the Viggen is an old design, aerodynamic laws are much more older. Plxdesi2 (talk) 14:06, 10 April 2013 (UTC)[reply]
Is the Viggen's canard a lifting surface during cruise? The references I recall stated that its purpose was twofold: firstly to increase lift at high angles of attack, not by contributing much lift itself, but by generating vortices which in turn rolled over the wing so that the wing generated significant vortex lift, and secondly to also contribute lift during takeoff and landing through the use of flaps. Clearly, during cruise any vortex lift would generate excessive drag, and landing flaps would not be used for similar reasons. I have never seen cruise lift mentioned as a function of these canards. But perhaps I am just badly informed?
Also, back in the day, the idea of lifting vs. control canards had not been distinguished. The Viggen canard was described as "close coupled" (e.g. Green, W. and Swanborough, G.; The complete book of fighters, Salamander (1994), Page 515). It is certainly not a control canard and, unless it contributes lift during cruise, not a true lifting canard either, its main purpose instead being to modify the airflow over the wing, hence "close coupled" - a type not envisaged by the "lifting vs. control" distinction.
Meanwhile, the present article only summarises such features, it leaves the detailed discussion to other pages. Using the word "lift" twice in one sentence is unnecessarily wordy, with "a lifting canard to increase lift" being a blatant tautology. Also, the idea that it is there for "pitch control" is wrong - it is a fixed surface and the movable trailing-edge surfaces are flaps not elevators. So can I suggest the alternative wording, "This model introduced the use of a close-coupled canard to help control airflow over the wing at high angles of attack and to provide increased lift for takeoff and landing." What do you think? — Cheers, Steelpillow (Talk) 18:44, 10 April 2013 (UTC)[reply]
I agree that "lifting...lift" wording is not fine. According to this 3-views drawing [1], the Saab foreplane has a calage of 4.5° ; it looks like a lifting canard. The main gear longitudinal position, at the nose of the wing MAC, confirms that as well. Althoug the foreplane is closer to the CG that the elevons, (canard flaps/elevons hinge arm lever ratio is about 0.43), IMO the front flaps are effective on pitch control, because when you add some front lift, you get a positive pitch moment AND you add another pitching moment thanks to the deflection decreasing the aft wing lift. To quantify this, I will do some analysis with AVL (Mark Drela software), that I am used to work with. I will compare the pitch moments of the front and aft wing separately, to answer if the canard is a true lifting surface or not and an effective pitch control surface or not. Probably the canard flaps were not used as control surfaces ; I do not have the information. Cheers, Plxdesi2 (talk) 21:53, 10 April 2013 (UTC)[reply]
AVL Viggen results. Although the canard lateral surfaces are only 0.13 x the main wing area, the foreplane area (including the fuselage) account for 0.31 x the main wing. The calage values of the drawing goes well for balance (canard 4°). At extreme aft CG (Neutral Point), pitch stability = 0 and the canard lift contibution is 35 % of the total lift, the canard CL being 2 times the wing CL. With a more forward CG providing a Cma (pitch moment derivative dCm/da) value of -0.20 (not very high), the canard lift goes up to 45 % of the total lift. "Closed-coupled" does not mean that the canard is not a lifting surface; for example, the Pou du ciel (Flying Flea) configuration. This aircraft is a true lifting canard configuration.
The canard flaps area is 0.38 x the elevators area, the flap lever arm is 0.33 x the elevator lever arm, so the pitch moment effect of the canard is much lower (about 0.2) than the elevators. As canard flaps are effective for pitch trim but not enough for pitch control, it is not a control-canard
IMO the expression "vortex lift" does not apply well to this configuration; this kind of extra lift comes with a very high sweepback angle (like Concorde or F-18 wing apex, or P-47/P-51 dorsal fins). The extra lift of this canard aircraft comes mainly from the positive canard flaps angle at high incidence, allowing a neutral or only lightly negative elevators deflection instead of high negative deflection in case of conventional delta wing planform. For CL = 1, AVL gives for example canard flaps at 17° and elevators at -2°. Plxdesi2 (talk) 13:22, 11 April 2013 (UTC)[reply]

The aircraft mounts missiles ahead of the wing. If it retains level flight at all, it is due to lift from the canards. Hcobb (talk) 20:51, 10 April 2013 (UTC)[reply]

The French 'Aviation Magazine International' nº 602, 15-31 Jan 1973, has a description of the results with different arrangements of the foreplane, regarding the Saab Viggen, by J Gambu and J Perard, and the Feb 23, 1985 issue of Flight International, an article by B R A Burns 'Canards design with care'; the Curtiss XP 55 Ascender featured a variable incidence foreplane with elevons in the trailing edge, and the modern Rafale and Eurofighter install inverted Vee fully moveable foreplanes, but without elevons; tailplanes in the V shape (Beechcraft) or foreplanes in an A configuration (Curtiss XP 55) act also as rudders.--Jgrosay (talk) 18:48, 20 April 2013 (UTC)[reply]

I agree that the 3-view and other images suggest that it is a lifting canard. Whatever, the whole description is peripheral to this article, so I have deleted it. Effort can be better spent correcting the misdirections and falsehoods in the main Saab 37 Viggen article. — Cheers, Steelpillow (Talk) 13:43, 11 April 2013 (UTC)[reply]

Just another effort... but personal work/analysis does not always comply with WP need for quotes and citations. Plxdesi2 (talk) 09:48, 12 April 2013 (UTC)[reply]

Minor surface features

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Are Winglets to be included here ? Plxdesi2 (talk) 09:48, 12 April 2013 (UTC)[reply]

Winglets are included in the previous section, as minor aerodynamic surfaces, because I felt at the time that they did more than just modify the wing characteristics. Are you happy with that or do you think they should be demoted to minor surface features? — Cheers, Steelpillow (Talk) 10:11, 12 April 2013 (UTC)[reply]

isoclinic wing

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as used on the Short SB.1 & 4 (Sherpa) experimental aircraft needs including, along with a matching image. Unfortunately I don't have much on it - is there a straight wing version?NiD.29 (talk) 01:53, 24 August 2013 (UTC)[reply]

Good point. Information from Short SB.4 Sherpa describes the aero-isoclinic wing as:
"This radical wing configuration was designed to maintain a constant angle of incidence regardless of flexing, by placing the torsion box well back in the wing so that the air loads, acting in the region of the quarter-chord line, have a considerable moment arm about it. The torsional instability and tip stalling characteristics of conventional swept wings were recognised at the time, together with their tendency to aileron-reversal and flutter at high speed. It was to prevent these effects that the aero-isoclinic wing was designed."
Unfortunately, this information is unsourced. Dolphin (t) 02:43, 24 August 2013 (UTC)[reply]
I don't see this as a distinct configuration, it's just a bog standard tailless swept wing configuration which happens to have structural and aerodynamic refinements. — Cheers, Steelpillow (Talk) 10:41, 24 August 2013 (UTC)[reply]
They went to the trouble of giving it a name. Specifically, the tips rotate and have a spar/rotation point further aft than normal - the double tapered plan-form that peaked my interest seemingly has nothing to do with it. Perhaps as a note or mention in the tailless swept wing configuration section? The name exists so should be included on the page.

As for sources... - Barnes, C.H.; Shorts Aircraft since 1900, Naval Institute Press, Maryland, 1989 ISBN 0870216627 pages 441-443 (or the British edition - not sure if that changes the page numbering...). Cheers, NiD.29 (talk) 18:54, 9 June 2015 (UTC)[reply]

The name describes the particular principle of interplay between structural deformations under load and aerodynamic characteristics. It does not describe the configuration of the gross physical form, any more than say "multi-spar" or "laminar-flow" do and is no more relevant to this article than they are. A straight wing with a main torsion spar along the centre of lift of the aerofoil section will be isoclinic under load. The all-flying wing tips were a common feature of GTR Hill's tailless designs and are not unique to the isoclinic wing; they were introduced as much to address stall and flutter characteristics as bending under load. Let me repeat, this is just a bog standard tailless swept wing configuration which happens to have structural and aerodynamic refinements. If you read your sources carefully, you will see that they bear this out. — Cheers, Steelpillow (Talk) 21:36, 9 June 2015 (UTC)[reply]

Wings in Nature

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This is fascinating stuff, for sure, but I came to this page looking for different forms of wings in animals. Should that get added to this page or made a separate page? I guess it would depend on how many different designs there are or something? And what about dandelion seeds and the like. It kind of looks like those fluff balls are made up of lots of wing-like structures. Would that count? Um the Muse (talk) 03:18, 9 June 2015 (UTC)[reply]

You might try the first link in the article - ie Bird flight#Wing shape and flight. This article is about aircraft wings - although most bird, insect and seedpod shapes are in fact covered (having been used in aircraft). The page is organized around the terminology used in aviation - a different page divided up by biological terminology would really be needed for a similar listing of animal forms as the two are not compatible.NiD.29 (talk) 07:02, 9 June 2015 (UTC)[reply]
You can note that this article now has a note at the top to direct readers to bird wing configurations. - Ahunt (talk) 12:25, 9 June 2015 (UTC)[reply]

M-wing

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The "changes in center of gravity with changing speed due to wing bending moments, along with a number of other advantages" are caused by aeroelastic effects. The cited sources make this clear. (There are some other effects which may be good or bad depending on the given design). Maury Markowitz (talk · contribs) does not seem to understand this and insists on adding the long version quoted, which highlights an arbitrary effect, I am trying to restore something closer to the original wording along the lines of "the undesirable effects of aeroelastic bending". This is both shorter and less biased towards one particular effect, altogether more encyclopedic and easier to read. What do others think? — Cheers, Steelpillow (Talk) 22:44, 11 November 2015 (UTC)[reply]

The wording after this edit is incorrect. Please note the difference between center of gravity and aerodynamic center. Burninthruthesky (talk) 09:34, 12 November 2015 (UTC)[reply]
So instead of fixing the wording you RVed? Can you explain your logic here? Maury Markowitz (talk) 12:14, 12 November 2015 (UTC)[reply]
The edit was both incorrect and disputed. Even if corrected, Steelpillow has raised valid concerns about the undue emphasis placed on one of the effects discussed in the sources. Burninthruthesky (talk) 12:50, 12 November 2015 (UTC)[reply]
The entire section was wrong, and still is. The primary advantage of the M-wing layout is that the wing as a whole lies closer to the lateral axis. Something like a tip stall, which occurs far to the "rear" in a conventional swept wing, is taking place close (longitudinally) to the root. This minimizes changes in center of pressure of the aircraft as a whole, offsetting one of the main problems of a swept wing design. The original text is precisely an example of undue emphasis, the M-wing raison d'être is not an attempt to reduce aeroelastic bending. So, then, I guess I have a concern about the original undue emphasis. Maury Markowitz (talk) 13:23, 12 November 2015 (UTC)[reply]
Pleas check out Diederich and Foss, whom I have now cited. Note in particular the last phrase on Page 1: "aerodynanic-center shift due to aeroelastic effects," If you can find cites for other causes of the aerodynanic-center shift which M-wings address, then we have a debate on our hands. Until then, we don't. — Cheers, Steelpillow (Talk) 19:40, 12 November 2015 (UTC)[reply]
I think that Maury Markowitz is headed in the right direction. The classic swept back wing suffers from pitch up due to tip stall. The wing tip (located behind the c.g. longitudinally) stalls at high AoA, most of the unstalled wing is now in front of the c.g. --> AoA increases further, making the stall worse. This is however unrelated to aeroelastic effects. The M-wing addresses the pitch-up problem by placing the wing tip (which is assumed to stall first) closer to the longitudinal c.g. by acutually compressing/folding the entire wing. — Preceding unsigned comment added by 81.173.158.171 (talk) 07:14, 20 November 2015 (UTC)[reply]
May I repeat what I just wrote, "If you can find cites for other causes of the aerodynanic-center shift which M-wings address, then we have a debate on our hands. Until then, we don't." You know, those WP:RS things that verify stuff. — Cheers, Steelpillow (Talk) 08:43, 20 November 2015 (UTC)[reply]

Waveriding

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The B-70 Valkyrie used waveriding, aka compression lift, in cruise. The purpose of this is not to increase the net lift as such, but to allow the craft to be trimmed to a lower AoA which reduces net drag while maintaining the same lift. Maury Markowitz (talk · contribs) does not understand this and insists on adding a longer and incorrect statement, saying that the waveriding effect is used to increase lift as well as to reduce drag. What do others think? — Cheers, Steelpillow (Talk) 22:44, 11 November 2015 (UTC)[reply]

When something changes the L/D ratio, there's always a risk of confusing the reader if it's not clear whether the airframe is kept at the same attitude, or adjusted to keep the lift the same. I think it's less confusing to refer to the real-world scenario. Burninthruthesky (talk) 09:47, 12 November 2015 (UTC)[reply]
Re-reading the section, I see that the article has once again been RVed into an incorrect state. "The outer sections of the XB-70 Valkyrie wing folded down, to reduce drag through generation of compression lift during supersonic cruise" is factual incorrect. The compression lift is primarily generated by the shock body at the front of the engine intakes, which is very well covered in the many fine references in the B-70 article. The purpose of the folding tips was to improve lateral stability without the need for larger vertical control surfaces. This is also well covered in the references, but Airplane Stability and Control contains a complete description. Maury Markowitz (talk) 15:32, 12 November 2015 (UTC)[reply]
The folded-down tips had more than one benefit. Lateral stability was one, so I have added that: thanks for spotting it. They also contributed significantly to the wave lift by reflecting the attached pressure wave back under the rear part of the wing. As Jones (U.S. Bombers, Aero, 1974) puts it, "Called Compression Lift, this principle markedly reduced drag". FYI the shock body in itself did not create the compression lift as you suggest. The direct cause of compression lift was the attachment of its pressure wave to the wing lower leading edge: it only worked well at cruising speed, when the Mach cone aligned with the leading edge sweep angle. Hope this helps. — Cheers, Steelpillow (Talk) 20:06, 12 November 2015 (UTC)[reply]
So you admit the original version was wrong? Excellent!
But the problem is it still has the part about "reduce drag through generation of compression lift". Compression lift is lift. It increases lift. It does not reduce drag. Quite to the contrary, like all lift generation, it increases drag. One might expect drag would increased when one places a large block of metal in supersonic airflow. The only correct statement would be "using compression lift generates less drag than a conventional wing generating the same amount of lift at the same high supersonic speed". I'm perfectly happy with that statement, but it has almost nothing whatsoever to do with the drooping wing tips.
It gets worse when you consider what actually happens in this case. Since the B-70 is a rear-wing aircraft, increasing pressure under the wing causes nose-down trim, in addition to what would normally be expected by mach tuck. This increases trim drag, the opposite of what is stated above. This was the second benefit of the drooping wingtips, which reduced the surface area at the rear of the wing and thereby caused a nose-up trim that counteracted this effect. This is also well referenced in the B-70 article.
I'm also not at all sure where you get the statement about "attachment of its pressure wave to the wing lower leading edge". Perhaps I simply don't understand your wording, but given that the shock angle at M3 is different than the wing sweep angle, I don't know what to say. But I do know how it actually works, which is because the air velocity behind the shockwave is slowed from M3 to M2.3, and as a result the pressure increases. It's the same basic principle as the oblique shocks used in an engine inlet. The result is that the entire area under the wing sees higher pressure. Aeronautics has a complete discussion on the topic, but unfortunately you can only see a tiny bit of it online here. They have an illustration you can see that shows how it works, and you can see in it that the shock wave is nowhere near the leading edge. A shorter treatment is mentioned here and here.
And finally, all of this is compounded by the statement above that the drooping tips "contributed significantly to the wave lift". No, they did not. Even the original 1956 paper notes a relatively small contribution (page 32), a number that is put at 5% in the other references. Ironically, all of this was abandoned that year due to wind tunnel tests on Hywards. You can see the reasons why in this presentation. There is continuing debate whether or not the tips had any contribution, which you can also find in the references.
The drooping wingtips were first and last a way to improve lateral stability. Everything else is secondary. Consider that both the F-103 and F-108 had the exact same problem at M3, but solved the problem in entirely different ways, and that the design was changed in response to stability needs, everything else be damed.
Shall I continue deconstructing, or can I just go ahead and make edits without having to go through the name calling, edit warring and pile-on again? Maury Markowitz (talk) 21:36, 12 November 2015 (UTC)[reply]
By all means drop "the name calling, edit warring and pile-on" which you have hitherto felt so necessary to this discussion, I can assure you it isn't, as can WP:CIVIL. But also, please discuss your substantive proposals here first, so we can work towards a consensus solution without constant reversions. There was at least one more benefit, to bring the centre of pressure forward, so it is clearly simpler to do what had been done with many other features mentioned in this article an abandon any attempt at a summary. You might like to raise the above points at Talk:North American XB-70 Valkyrie - the article is not entirely in agreement with you. — Cheers, Steelpillow (Talk) 08:49, 13 November 2015 (UTC)[reply]

Aspect ratios

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This article is a summary list of many things with just enough information on each to make the point, it does not go into detail on any of them. Aspect ratios need to be kept to low, medium and high, nothing less general than that. The images are just sketches and can change at any time, I have indeed changed a good few of them over the years: nobody can rely on them for detail measurements, so special images would need to be prepared. The place for such measured images and associated numbers would be in the main article on Aspect ratio (aeronautics), which is only one click away. Does anybody still have a problem with that? — Cheers, Steelpillow (Talk) 17:40, 19 November 2015 (UTC)[reply]

Meanwhile, edit comments are not the place to carry out a discussion, that is what this page is for. Also, edit warring by repeated reversion of others can lead to an editor being blocked, even IP editors can get the treatment. For your own good, please stop warring and raise any points of concern here. — Cheers, Steelpillow (Talk) 17:49, 19 November 2015 (UTC)[reply]
I agree. Calculated aspect ratios for the diagrams are WP:OR and are not needed in this article, regardless. Even if correct it is too much fine detail for this article coverage and scope. - Ahunt (talk) 20:03, 19 November 2015 (UTC)[reply]
As for the summary argument, I can see your point. However, the aspect ratio is a complex number, no directly assible from the pictures.
Everybody can judge an agle by looking at it. It is obvious that sweep angles are typically between 20 and 60 degrees and dihedral angles are equally obvious. For biplanes the spacing between wings can quickly be judged to be in the neighborhood of one chord. It is simply not that easy for aspect ratios.
In my opinion it is very useful for the reader to get a number to go with the aspect ratio images. This gives a feelding for the "neighborhood" of the numbers. Even if its only for a quick overview. They certainly don't make it a worse article.
The calculated aspect ratios are most definatly not WP:OR. Doing basic calculations is explicitly excluded in the article. — — Preceding unsigned comment added by 89.0.108.176 (talk) 00:22, 20 November 2015 (UTC)[reply]
These weren't just basic calculations, these were measurements and then calculations. Regardless of that, this doesn't improve the article, it is just too much fine detail for an overview article like this. - Ahunt (talk) 00:46, 20 November 2015 (UTC)[reply]
Yours is the opinion of a pilot, mine is the opinion of an engineer... — Preceding unsigned comment added by 81.173.158.171 (talk) 07:02, 20 November 2015 (UTC)[reply]
The only number that has any place in this article is the number of wing planes. And the argument that aspect ratios are special is rubbish - anybody can tell the difference between stubby, medium and long. — Cheers, Steelpillow (Talk) 08:38, 20 November 2015 (UTC)[reply]

Low wing vs. Mid wing

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I have one question: in the German Wikipedia the Grumman F6F Hellcat is described as a Low wing monoplane (in contrast to the predecessor model F4F Wildcat as Mid wing). Also in the German Wikipedia the P-47 is described as a Mid wing monoplane. Comparing these two planes (F6F and P-47) show that both planes are similar constructed. My question is: what is the correct specification of the F6F Hellcat? Low or Mid wing? --Peettriple (talk) 08:06, 22 March 2016 (UTC)[reply]

For Wikipedia it should depend on how recognition books have decided to classify them. The wing roots of both are below the midpoint of the fuselage side but mounted at the widest part so both are ambiguous but the former criteria should trump the latter and both should normally be considered low wing types - although the P-47 does have more fuselage below the wing than the F6F. When in doubt, check sources. - NiD.29 (talk) 11:11, 22 March 2016 (UTC)[reply]
Yes, absolutely, whatever reliable sources say. But sometimes the sources show but don't tell. Such photographs and drawings show clearly that both types should be classed as low-wing. — Cheers, Steelpillow (Talk) 20:59, 22 March 2016 (UTC)[reply]

With reference to the Variable chord section

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How do varying incidence and thickness change the chord? Thanks.Pieter1963 (talk) 00:20, 18 September 2021 (UTC)[reply]

Thanks for spotting that. I will rename the subsection "Variable section" and see if that sticks better. — Cheers, Steelpillow (Talk) 05:21, 18 September 2021 (UTC)[reply]
I don't think variable incidence alone, if that is all it is, would qualify as a change in section, in which case perhaps it should be the sole entry in its own section. However the only example I've come across, the Crusader, incorporates variable camber at the same time. So that one, at least, would be variable section after all.Pieter1963 (talk) 23:54, 18 September 2021 (UTC)[reply]
I don't think that separate sections is sensible, it would just look ridiculous and confusing. One might argue that varying the incidence is in fact presenting a variable cross-section to the airflow, and that the English language is flexible enough for this to be titled "Variable section" without loss of clarity. — Cheers, Steelpillow (Talk) 16:31, 19 September 2021 (UTC)[reply]
Good points. It keeps the article on track, well-managed.Pieter1963 (talk) 16:12, 20 September 2021 (UTC)[reply]

difference between wings with straight, rectangular leading edge and tapered trainling edge vs. the opposite vs. symetrically tapered wings (planform)?

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what's the difference please between wings with straight, rectangular (relative to the fuselage, regarding planform) leading edge and tapered trailing edge (e.g. https://www.williamssoaring.com/images/fleet-images/ask21-planform-450x.jpg) vs. the opposite (e.g. https://www.j2mcl-planeurs.net/dbj2mcl/planeurs-machines/3vues/Masak_Scimitar-I_3v.jpg) vs. symetrically tapered wings (planform) (e.g. https://cdn.britannica.com/63/189163-050-C6C43205/Glider.jpg)? advantages and disadvantages? and what's the effect of flaps coming down with type one, especially if it's a plane with short, stubby wings and strong tapering? the air-flow should be directed away from the wing-tips towards the fuselage reducing the wing-tip-vortex...? thanx! HilmarHansWerner (talk) 11:29, 29 September 2023 (UTC)[reply]

This page is reserved for discussions on how to improve the article, it is not an open forum. I'd suggest you check out Stack Exchange, I recall that they have an aircraft forum or two. — Cheers, Steelpillow (Talk) 15:00, 29 September 2023 (UTC)[reply]
well, how about improving the article by taking up and answering the questions above which an inquisitive reader might ask himself or herself? greetings. HilmarHansWerner (talk) 16:07, 7 April 2024 (UTC)[reply]
These issues are complex and go way beyond the scope of this article. — Cheers, Steelpillow (Talk) 18:32, 7 April 2024 (UTC)[reply]
I agree with Steelpillow.
A useful place to explore the original question is the book “Aircraft Design: A Conceptual Approach” by Daniel Raymer (1992). It is published by the AIAA. Also see Daniel Raymer#Bibliography. Dolphin (t) 21:53, 7 April 2024 (UTC)[reply]

Requested move 27 January 2024

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The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review after discussing it on the closer's talk page. No further edits should be made to this discussion.

The result of the move request was: Not moved. WP:SNOW oppose and zero rationale given, no need to waste time going through the motions. (non-admin closure) ᴢxᴄᴠʙɴᴍ () 05:43, 29 January 2024 (UTC)[reply]


Wing configurationWing-body-tail configuration – Please place your rationale for the proposed move here. Halfcookie (talk) 12:44, 27 January 2024 (UTC)[reply]

Oppose No case has been made that the current title is inadequate or the proposed new title will be superior. The current title is much simpler than the proposed alternative. I prefer the current title. Dolphin (t) 13:11, 27 January 2024 (UTC)[reply]
why?blindlynx 15:08, 27 January 2024 (UTC)[reply]
WP:SNOW Oppose. "Wing configuration" is the standard term for the subject of the article. Body, tail and engine configurations have their own articles, and are treated here only in relation to the main wing layout. No rationale is offered by the OP as to why this should be challenged. — Cheers, Steelpillow (Talk) 16:58, 27 January 2024 (UTC)[reply]
The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.