Talk:Stabilizer (aeronautics)/Archive 1

This is an archive of past discussions about Stabilizer (aeronautics). Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page.

Archive 1

Can a canard be a stabiliŽer?

This has been discussed recently here, where consensus appeared to be that a canard surface could sometimes be a stabiliser. Stodieck has made a number of changes, including the unreferenced assertion that, "It is a common misconception that the small forward wing of a 'canard' aircraft is a 'forward stabilizer'". This understanding has influenced other edits throughout the article - here's the diff - so I propose that, due to this editor's persistence in the face of consensus, it is best to revert them wholesale and let Stodieck unpick their own mess. But an edit war looms if we do not quickly reach consensus on this approach. Opinions welcome. — Cheers, Steelpillow (Talk) 21:08, 2 June 2012 (UTC)

True or false, the "common misconception" comments require a reliable reference; otherwise it's a WP:POV issue and breaches WP:Verifiability. If this reference cannot be produced quickly then the comments should go. Once, and only after, this is sorted do we need to focus on what the majority of reliable sources think people mean by stabilizer: is it a just a bit of an aeroplane or must the term also accurately describe the function of that bit? FWIW, my Aviation Dictionary (Kumar) says simply that it's the fixed horizontal bit at the back that I call the tailplane. "Tailplane" is (probably) more common (POV?) usage in the UK, together with empennage etc, is descriptive and does not judge function.TSRL (talk) 22:37, 2 June 2012 (UTC)

Don't revert an entire page. Delete the statements you don't like. Any elementary text on flight describes how horizontal stabs work and by extension why static canards are destabilizing. They all are references that can be quoted here. If you are referring to actively controlled canards which are used as stabilizers then you need to establish that context. Actively controlled canards-as-stabilizers are also as old as the Wright brothers. But you need to describe what the sensor is and what controls the canard angle of attack. For the Wright's, the sensor was their eyes and they directly controlled the canards angle of attack. Today it is a gyro and an electronic system in control.

"In order to achieve longitudinal stability a canard surface is trimmed to increase lift as speed increases. This equates to a negative coefficient for trim drag." Who trims the canard?, The pilot?, Electronics? (1) The context in which this statement might make sense has not been established. "in order to achieve longitudinal stability a canard surface is trimmed to increase lift as speed increases." Why? How does this work? (2) Where is a verifiable reference for an average reader? (3)

"This equates to a negative coefficient for trim drag." Ok. What does this have to do with longitudinal stability? (4) Is that supposed to be self evident? (5)

The reference is not widely available. The context in which this statement was made is not represented in the wiki and people are applying it out-of-context. Many editors are unaware that there is a context. There is no consensus among the editors so it is better to not mention the issue in the wiki at all. The Wright brothers clearly did not understand the issue, at least not until all the crashes that lead to the model B. It is not an issue that can be resolved by debate alone.

I suggest that each editor go through each question above and document and post their own responses to each question. I count 6 questions. The sixth question is; when you answered these questions, did you think you were talking about a type of aircraft or a small forward wing on that type of aircraft? (6) Several editors, I noticed, are not clear on this.

(1.) Wiki article doesn't say. (2.) Sounds like the nose would shoot straight up uncontrollably as speed increases above lift off. Apparently it doesn't work at all. (3.) There isn't any. For me it would be in the San Francisco main library on the 4th floor. I don't' live near by. (4.) Absolutely nothing. (5.) Apparently, but it isn't. (6.) A forward wing.

Now show me your answers. --Stodieck (talk) 01:24, 3 June 2012 (UTC)

While one should not generally revert multiple edits, many of those I sought to revert were adversely influenced by the PoV expressed, including deletion of other editors' material, to the detriment of the article at many points. Expecting other editors to unpick so many deletions individually seems to me unreasonable, so I am suggesting that unless and until Stodieck can establish their PoV as consensus, none of their edits should stand.

Stodieck says that"Any elementary text on flight describes how horizontal stabs work and by extension why static canards are destabilizing.". The first part is true, the second appears to be only personal inference and PoV - unless anyone has a reference for that specific argument by extension? The situation with canards is of course far more complicated anyway.

Clancy's specific text occurs in a discussion of "The tailplane" and specifically its effect on trim drag. He says that, "One of the advantages of the so-called Canard configuration is that, with the tail ahead of the wing instead of behind it, it carries an upload for trim at high speeds. This is equivalent to providing negative trim drag." Other editors have vouched that they can understand the article's paraphrasing of this perfectly well. How we accomplish the change in trim as the aircraft accelerates is neither here nor there, aircraft designers can be very creative people.

Clancy elsewhere describes the purpose of trim as to achieve equilibrium. The original discussion, which I referred to when opening this one, showed a clear consensus view that a contribution to the overall stability characteristics of the craft warranted the description of a canard as stabilising or a stabiliser. One may wish to argue the semantics of "equilibrium" vs. "stability", but that is very different from deleting the paragraph willy-nilly without discussion which is what Stodieck has now done more than once.

Consensus among editors hinges on reliable referencing. Clancy is one such reference, other relevant ones have been painfully slow in coming forward. Stodieck's view that Clancy is being taken out of context is a personal PoV unless an alternative reference can be found. Stodieck frequently asserts that nowadays, better and more accessible references abound. Let us see these references, then. That way, perhaps we can find a way to explain things better and Clancy can gracefully retire from the wiki. Until then, old as he is, he is just about the only basis we have for reaching consensus on this point.

So the urgent question remains:

is Stodieck's PoV sufficiently established to allow his edits to stand?
should they be reverted piecemeal, argument by argument,
or can we revert the whole set and ask Stodieck to provide references for each occasion where he deletes material contradicting his own PoV or adds material asserting it?

— Cheers, Steelpillow (Talk) 14:22, 3 June 2012 (UTC)

OK, so I reverted the multiple expressions of the PoV that the majority have agreed is untenable. At the same time I kept some of Stodieck's valid edits, but the bulk diff is not good at paralleling up complex changes, so I could not pick them all out. Happy to come back and do so in due course, or others might not want to wait. Hoping this is a way forward. — Cheers, Steelpillow (Talk) 10:53, 5 June 2012 (UTC).

Exactly what was the "PoV that the majority have agreed is untenable"? And what is the vote? Was the offending statement even in the article when you edited? Where is the whole description of adjustable stabilizers and the Concord? Was that also untenable?

Here is a good public domain reference on the use of canards to destabilize the Eurofighter, A static canard would be used here even if it where not also used as a movable control surface. The article of interest starts at "Foreplane" and details the optimum sizing and positioning of the fore plane to provide maximum destabilization at minimum induced drag. Again, anytime the wing surface is in front of the center of mass. It acts as a destabilizer. This is widely misunderstood, precisely as the original article stated. That is why you will always find some references that make this kind of statement. And I don't' see any consensus on this point in this forum. [Eurofighter: Aerodynamics see foreplane]--Stodieck (talk) 18:04, 5 June 2012 (UTC)

Your PoV was of course that a canard foreplane cannot act as, or be referred to, as a stabiliser. Other editors have commented against it in the section immediately below, as well as here and here. I have also discussed with you both it and how to engage positively with the editing community, in this section and here. You have been warned about your behaviour many times on your talk page. Your response to me at least has often been to villify and insult me or make aggressive remarks: examples of which you even posted on my own talk page (another big no-no) here and here ([Update] for the record on that last, I had actually started the discussion and was at that point waiting for you to add to it). So - you already know that deleting another editor's work three times will not be tolerated. I myself have repeatedly explained the need to discuss and reach consensus before you do this sort of thing, not afterwards. Third strike and I will report you. You have much knowledge to offer Wikipedia, but your behaviour is getting in the way again. Re. your edit comment, you evidently didn't read my note above - I will take a look at your section on adjustable stabilizers and restore all that does not show your untenable PoV. — Cheers, Steelpillow (Talk) 19:38, 5 June 2012 (UTC)

OK so I restored much of the bit on adjustable stabilisers - it did need editing for neutral PoV - and one or two other chunks I found too. I may have missed the odd minor edit, but it's probably better to work from scratch than trawl through the diffs for those. Hoping we can move forwards now. — Cheers, Steelpillow (Talk) 20:15, 5 June 2012 (UTC)

Now restore the pictures and captions for the adjustable stabilizer and the Concorde. Why were these removed? The last version of the page you reverted 3 times does not seem to include the POV you mentioned. At most it is a 3 line edit. Now, should I write the section for canard destabilizers based on the NATO article referenced above? Do you want to write the section explaining technically how a foreplane can be both a stabilizer and a destabilizer? Destabilization is the primary reason these combat aircraft have canards. The editors of the article assume that the reader knows that canards are destabilizers, thats been common knowledge for 100 years. I have already dropped refs for that. [Eurofighter: Aerodynamics see foreplane] --Stodieck (talk) 02:33, 6 June 2012 (UTC)

Stop doing full page reversions without bothering to read the articles. You will always get both barrels from me and anyone else affected. If you don't have time to read and think, don't edit. Your explanations of "why" you have to edit like this disqualifies you as a serious editor. You are saving yourself a few minutes and costing everyone many days. Stop doing full page reversions claiming that you have consensus on a change that might affect one paragraph. The conversation is still quite open. Most of the very good references on the web turn out to have clear copyright conflicts. Sorting through them is time consuming. I am amazed not to be able to download Clancy somewhere for free. I can also quote non-veiwable references, but why? --Stodieck (talk) 02:33, 6 June 2012 (UTC)

You know your minor edits better than I do and they are much easier for you to restore - you could have done it in less time than the above rant took you (although I am unsure why you want to illustrate a tailless type here - Stability (aircraft) currently redirects to flight dynamics). The lack of reliable references on this topic has dogged it for years. I can find nothing in WP:CITE about online vs. dead tree sources. If the only reliable sources you have are books, that is way better than nothing. — Cheers, Steelpillow (Talk) 10:07, 6 June 2012 (UTC)

The Eurofighter article is only talking about foreplanes in relation to the Eurofighter design. Showing that in one design a canard is destabilizing does not show that it is destabilizing in all. GraemeLeggett (talk) 11:27, 6 June 2012 (UTC)

No, the elementary technical literature on the subject shows that canards winglets are destabilizing. This should be expected from what is a horizontal stabilizer constructed backwards. The general lack of canard winglets on aircraft from 1910 to 1970 shows that this was common and orthodox knowledge among designers. The historical literature shows how wide spread the confusion has always been about the subject. This viewpoint is not being represented here. Instead of being a source of knowledge, these articles become a repetition of the psychology-of-flight mythologies that prevented actual manned flight. This is due to the editing tactics of a single editor. If you think "they are much easier for you to restore - you could have done it in less time" then make yourself heard here and go do a revert of SPs edits until an actual consensus has been achieved here. At the moment all we have is SPs self assertion that consensus was achieved which is clearly garbage. --Stodieck (talk) 13:17, 6 June 2012 (UTC)

"Showing that in one design a canard is destabilizing does not show that it is destabilizing in all." But you cannot show even one really technically documented case of a canard acting as a stabilizer. It is irresponsible to assert, as this article has, that canards can be stabilizers. It is one thing to not say anything publicly, and argue about the issue here. It is quite another to assert that a canard is stabilizer publicly, and then argue the contrary here.

You are risking the lives of other people who might take this to heart. --Stodieck (talk) 00:29, 8 June 2012 (UTC)

Stodieck continues to delete other editors' work wholesale and add unreferenced remarks supporting his personal PoV ( see for example this diff), all without any kind of positive discussion or consensus. I am getting tired of holding it all back on page after page - he's doing it again while I write this. How do we escalate this disruptive behaviour to get some real arbitration into the process? Once that calms down, technical discussions can follow. — Cheers, Steelpillow (Talk) 16:51, 8 June 2012 (UTC)

The text difference is largely the elimination of literally redundant text on this page, read the original. You are violating WP: NPOV by eliminating a viewpoint and feigning consensus. The text said that the canard stabilizer issue is controversial and that is clearly true. It also provides references sourced by you and others so the viewer has access to that info to form their own opinions. You have suppressed that.

You have stated that. "a horizontal stabilizer is called a tailplane. When placed at the front, it is called a canard or foreplane." A canard is not an alternative way of saying horizontal stabilizer, they are different things. The trigger on your revolver is not a thumb rest and the back of the pistol is not the front. A horizontal stabilizer is NOT "called a tailplane", but it "may also be called a tailplane." --Stodieck (talk) 17:35, 8 June 2012 (UTC)

You have been told over and over that you need to discuss these changes before crashing ahead.

For reminders you were given on the importance of referencing your PoV and the importance of verifiability over perceived truth, see here. As yet you have provided no reference to support the statement that the matter is controversial. I was careful to keep the references you did add, and I think an image. To quote Garrison, whom we both reference, "... the airplane would tip over if some balancing force were not provided. This is the function of the stabilizer. If it's in the back it typically pushes downward, and if it's in the front it lifts upwards." [1]. I find it hard to reconcile sources such as this with your discussions above and elsewhere: it is crystal clear that a canard foreplane may act as a stabilizer and be referred to as such. The Bushranger and GraemeLeggett below, Ahunt and Hcobb here would all appear to agree with Garrison and myself - I'd call that a consensus, even if Dolphin51 takes if anything a view even further from your own here.

If you would like to propose a restructuring of the article, including deletion of other editors' contributions, then let us have that discussion separately - beforehand. And you will need to keep that PoV out of it. — Cheers, Steelpillow (Talk) 19:49, 8 June 2012 (UTC)

It is not your role, nor anyone else's role, as an editor to determine which viewpoints represent orthodoxy in the Wikipedia. It is your role to to assure that all reputable viewpoints are represented. You are violating WP: NPOV - all significant views that have been published by reliable sources - . You can determine which viewpoints represent orthodoxy on your own website. Doing so here creates legal liabilities for the Wiki since you claim to be associated with the administration.

Garrison is the reference to support the statement that the matter is controversial. But failing to notice that the issue is controversial is like failing to notice that the Queen Mary is in your outhouse. Garrison states "once you accept that a "tail first" aircraft can be stable . . . ", clearly expressing the idea that this was not orthodox thinking, that it was controversial. The only viewpoint you are permitting in this article is that it is that "canard" is just another word for horizontal stabilizer, that this is orthodoxy. This violates NPOV and is flatly irresponsible. The destabilizing effect of canards has in fact been understood and part of orthodox design background for a hundred years. - You have eliminated the mainstream viewpoint.

Garisson and others have referred to canards as stabilizers. For the most part, this of the noise of thinking and discovery. I don't think any of those seriously involved in the subject would actually argue that the canard is actually generating stabilizing forces, i.e. on second thought, that the canard is a stabilizer. This is why I stated that calling a canard-a-stabilizer is misleading. - You eliminated this viewpoint.

Garrison states that the increase in coefficient of lift of the main wing must exceed that of the canard. That is to say that, the main wing is providing the stabilizing forces and is serving as the horizontal stabilizer, not the canard. - You have repeatedly eliminated this statement. The reference is Garrison. The forces generated by the canard, per se, are always destabilizing. You do not understand the physics.

What are the characteristics of the coefficient of lift of a canard required to make a canard aircraft stable if the center of mass is otherwise too far aft? The reference is Garrison. That there is such a requirement, is not mentioned here on the wiki. Nor are there any technical references listed on the subject. This is not a problem for horizontal stabilizers. Every elementary textbook on flight shows the diagrams and has an explanation.

Your statement says, "the foreplane acts to help stabilise the craft by moving the centre of lift forward." Show me your ref. "Moving the centre of lift forward" in relation to the CM destabilizes the aircraft. BTW, could you start spelling stabilizer correctly?

Garrisons comment; "The airplane would tip over if some balancing force were not provided. This is the function of the stabilizer." Actually, this is the function of pitch control not the stabilizer. The physical horizontal stabilizer is used for both functions but the functions and calculations are separate entities. The noise of thinking.

How is an unstable aircraft kept aloft or stabilized with a canard? - You eliminated this explanation.

Canards had not been seen for 60 years when they were re-introduced as destabilizers on combat aircraft. - You eliminated this statement and reference - The Eurofighter is not an exception. Go find your own references. Technically canards are always destabilizing.

I have not intentionally deleted other editors' contributions. I did try to to remove redundant explanations of what a horizontal stabilizer is; one filed under "tailplane"; of what an adjustable stabilizer are, and what elevators are. Why are these redundant entries there? I did not remove the trim speed statement I preserved it.

If you do not respond to my points, this page may be edited at any time as per Wikipedia policy, "If you don't want your material edited, don't put it here." You are in violation of WP:NPOV, not your personal definition of NPOV. --Stodieck (talk) 18:04, 9 June 2012 (UTC)

No. It is a Wikipedia editor's role to allow that all, and only, referencable or attributable viewpoints may be represented. Reputability (or truth) has nothing to do with it. Have you read the WP:VERIFY and WP:NOR policies thoroughly? Garrison explicitly describes placing the stabilizer in front of the main wing. That is attributable, so it goes in. He does not state that the issue is controversial, that is your interpretation. So too is your application of the noise of thinking. Editorial interpretations are not attributable, they are original research, so they stay out. That is all.

(FYI I can think of at least four canard designs built and flown in as many countries between 1929 and 1945. That's a gap of only 22 years to the Viggen's first flight.) — Cheers, Steelpillow (Talk) 20:35, 9 June 2012 (UTC) [Update] Even the Viggen was not given canards in order to reduce stability in pitch, although that would probably have been one effect. Their purpose was to direct airflow over the wings at high angles of attack, and were even given flaps to help with this. The rash of designs that soon followed from IAI, Atlas and Burt Rutan also had other benefits than pitch stability in mind. That would come later, as designers began to understand canards better. — Cheers, Steelpillow (Talk) 21:50, 9 June 2012 (UTC)

OK, and I have rebalanced the sections to address your point about reducing duplication. — Cheers, Steelpillow (Talk) 22:09, 9 June 2012 (UTC)

Even Burt Rutan abandoned canards after he began to understand canards better, around model 143. "four canard designs built and flown" does not address any questions being discussed here, nor would a million canards. We're not talking about whether canards fly or not.

This is a technical article, not a history of press bloopers and off hand comments related to canards. You need to find a technical description of how a canard stabilizes anything. Good luck. Even differential CoL relies on the main wing to provide stabilizing forces, not the canard. Does differential CoL produce static or dynamic longitudinal stability? What are the stability margins? What are the damping characteristics? Does any actual aircraft fly that way?

WP: NPOV - all significant views that have been published by reliable sources - While we are waiting for yours, you should restore those points made above. Or address each one individually.

Garrison states, "The role of the feathers of the arrow is now taken by the main wing rather than by the small auxillary surface you think of as the "stabilizer". Here he accepts that the main wing has become the stabilizer in spite of the misleading appearance that the canard is a "forward stabilizer". This is the reference you are using in your own "canard stabilizer" entries. You failed to read your own ref. It is consistent with my original article that you reverted. --Stodieck (talk)

— Preceding unsigned comment added by Stodieck (talk • contribs) 09:20, 10 June 2012 (UTC)

Garrison's is a useful discussion because he acknowledges both approaches (as I do) - that is, he does not deny either. You deny one of them, and this denial is what you are unable to reference. See also the NASA references in the next section (when their server comes back up) - or is NASA not august enough for you?

BTW, my reference to four designs and a gap of 22 years was in response to your claim that the gap was 60 years. And no, it is not directly relevant, that was why I put it in brackets and prefixed it with "FYI". Was that not clear enough for you? — Cheers, Steelpillow (Talk) 11:41, 10 June 2012 (UTC)

This is getting beyond a joke

And specifically, Garrison does not make the claim that "Passive stabilizers are always placed behind the center of gravity." as Stodieck spuriously referenced. As I quoted above, he explicitluy allows it to be in front: "... the airplane would tip over if some balancing force were not provided. This is the function of the stabilizer. If it's in the back it typically pushes downward, and if it's in the front it lifts upwards." and, bottom para of column 2 running into column 3, he explains how this works for a passive canard. This misuse of references is wholly unacceptable - it even seems to have fooled Graemeleggett for a minute there. And it's not the first time. I have had enough. — Cheers, Steelpillow (Talk) 12:10, 10 June 2012 (UTC)

OK, so I posted on WP:ANI at disruptive editor with unsustainable PoV. Hoping others of you can contribute to the discussion there.— Cheers, Steelpillow (Talk) 13:55, 10 June 2012 (UTC)

Garrison states, "The role of the feathers of the arrow is now taken by the main wing rather than by the small auxillary surface you think of as the "stabilizer". That is to say the stabilizing effect of feathers of the arrow is now being handled by the main wing not the canard. It is a verbatim quote. He is commenting on the his own confusion in thinking about the HSTAB and the canard function, exactly your problem. Just as importantly he was just figuring this out as he wrote the article. --Stodieck (talk) 16:31, 10 June 2012 (UTC)

the exact phrase is "You could say that the role of the feathers of the arrow is now taken by the main wing rather than by the small auxillary surface you think of as the "stabilizer". His later statement in the same article doesn't put quotes round the s-word. "This is the function of the stabilizer if it's in the back it typically pushes downward and if it's in the front it lifts upward." GraemeLeggett (talk) 16:56, 10 June 2012 (UTC)

Yes I understand this, Graeme. But the stabilizing function actually does shift to the main wing. It is not just a mater of speaking. The canard actually always does produce forces that are destabilizing. The incremental forces are similar on both surfaces but the canard is in front of the center of mass and the main wing is behind it. Their contributions to stability are exactly opposite. It is vital not to propagate the idea that they are the same thing. Too large a horizontal stabilizer and the plane will fly more slowly, too large a canard and the plane will flip over 180 degrees; the canard, NOW truly a horizontal stabilizer, will guide the plane to a tail first crash. I consider these differences to be significant, and not a joking mater.

The Oxford English Dictionary documents the way people use language, the Encyclopedia Britannica documents how things actually work. This wiki is not presented to the public as the OED, it is presented as an encyclopedia. It requires encyclopedic references, and actual technical descriptions, not framing maters of speech as maters of fact. Low speed physics does not have a viewpoint. --198.228.215.36 (talk) 20:22, 10 June 2012 (UTC)

Curtiss XP-55 "But the Wikipedia said that canards are stabilisers!" "That's stabiliZer, you should have read the edit history and talk page!"

The theory of how a horizontal stabilizer works is included in every elementary text on flight. The theory of how a canard "stabilizers" works is not included in these texts because they are not static stabilizers. This has been understood for 100 years, it is hardly an "unsustainable PoV". I can search google on any goofy theory and find a "reference" somewhere. --Stodieck (talk) 18:43, 12 June 2012 (UTC)

Here is a reference in a popular elementary text on aerodynamics, "The illustrated guide to to aerodynamics", Tab books, H.C. Smith, 2nd edition, page 279 Use the index to go to page 271 and then page to 279. "At first this configuration appears to be very desirable; however, there are several disadvantages to the canard arrangement. The canard surface will increase lift in lift and, hence, in nose-up moment, with increased angle of attack: destabilizing. Stability can be provided by the wing, but this requires the the wing always be behind the CG in order to give a nose down moment . . . .

This discussion was preceded by a discussion of the Wright brothers use of canards. Here is a reference to the events that lead to the abandonment of the canard by the Wright's after a crash that killed a passenger while Wibur was piloting: http://www.wrightflyer.org/Papers/SETP01_Culick.pdf --Stodieck (talk) 22:16, 12 June 2012 (UTC)

A plain explanation

Here's another way of looking at the issue. It is greatly simplified and I am hoping that the non-technical reader will be able to follow the gist of it.

Any conventional aerofoil is unstable in pitch, and any ordinary lifting surface so constructed is unstable in pitch: any small pitch-up movement causes the centre of lift to move forwards, increasing the tendency to pitch up, so the thing flips up out of control.

The classic solution to this is to have two surfaces, one behind the other. The overall centre of lift now sits in between those of each individual lifting surface, with each surface exerting a lifting force on either side of it: in steady flight, these forces balance out. Provided things are set up right, a small pitch-up movement will increase the lift on the rear surface more than the front. This lifts the rear and therefore pitches the nose back down to stabilise (add "z" to taste) the aircraft.

Thus, the craft is stabilised by the relationship between the fore and aft lift components.

It is common - as has been referenced by several editors - to call the larger of these two surfaces the wing, and the smaller the horizontal stabiliser - or, if they are of comparable size, then we call both of them wings (in tandem).

One may note that the rear surface "wins" with the greater change in lift and therefore in a technical sense it stabilises the action of the forward surface, while the "losing" forward surface is doing its best to destabilise. However, nowhere in the literature is it attested that this forbids a small forward surface to be called a "stabiliser" - everybody understands that its action stabilises the craft as a whole.

This article is titled "Stabilizer (Aircraft)" and therefore, because of the above, such a small forward surface must be addressed as one kind of stabiliser.

— Cheers, Steelpillow (Talk) 20:59, 26 June 2012 (UTC)

Of course, there are many technical rabbit-holes one might go down, such as pitching moments rather than lifting forces, downforces instead of lift, variations that behave differently and so on, but the logic of the above is sound - don't get distracted by bad bunnies. — Cheers, Steelpillow (Talk) 21:03, 26 June 2012 (UTC)

About that edit war...

Indented line ...I don't have time right now to go through the revisions and see what may or may not be right. I did, however, find an article by the master, Peter Garrison, that might help shed some light on the subject. "Three's Company". - The Bushranger _{One ping only} 16:28, 3 June 2012 (UTC)

Nice find. Barber starts simply. "Longitudinal Stability in an aeroplane is its stability about an axis transverse to the direction of normal horizontal flight, and without which it would pitch and toss." and then talks of longitudenal dihedral and angle of incidence but finishes with "Aeroplanes have, in the past, been built with a stabilizing surface in front of the main surface instead of at the rear of it" (The Aeroplane Speaks p70, 75). GraemeLeggett (talk) 20:22, 3 June 2012 (UTC)

Another quote "The horizontal stabilizer prevents an up-and-down motion of the nose, which is called pitch. (On the Wright brother's first aircraft, the horizontal stabilizer was placed in front of the wings. Such a configuration is called a canard..." this page is intended for college, high school, or middle school students NASA. also from the same august body "On some aircraft, the pitch stability and control is provided by a horizontal surface placed forward of the center of gravity" GraemeLeggett (talk) 17:55, 7 June 2012 (UTC)

Current round of reverts

The important thing here is that several editors besides me have agreed that a canard that helps provide stability may be called a "stabilizer", and several references have been put forward to back that up; here, here, here, here and here. So unless this clear consensus can be reversed, it must stand. — Cheers, Steelpillow (Talk) 17:42, 19 June 2012 (UTC)

BTW, re. static stability, I think Stodieck is correct - within itself a static foreplane is destabilising. It is only the interaction with the other lifting surfaces which provides overall stability. — Cheers, Steelpillow (Talk) 17:42, 19 June 2012 (UTC)

From GliderMaven; "They obviously do increase *static* stability, since if you suddenly removed a lifting canard in flight, without doing anything else, the front of the aircraft would drop rather markedly." Sorry, this is called pitch control, not static stability. Static stability implies the ability to hold a fixed average pitch only, not whether that fixed pitch includes level or not. That is pitch control. Dynamic stability implies freedom from oscillation in pitch about an average fixed pitch point. That is not being discussed here.

The best general reference, that I know of, that has some online visibility is; "The illustrated guide to to aerodynamics", Tab books, H.C. Smith, 2nd edition Page 279 mentions the destabilizing effect of canard foreplanes. Stability and control are on pages 157 to 164. Unfortunately pages 161 and 162 are not viewable online. But the book is widely available here in the US. The Culick reference also covers this in detail.

No I don't agree that there is consensus on calling canards stabilizers. If these editors want to weigh in on this they need to do so in person here in talk.

No. They have made their point. I have linked to their diffs. That is all that is required. The idea that the same discussion needs to take place on page after page is just silly. That is one of the things that internal linking and diffs are for.

The last two are talking about the stability of canard airframes, not canard foreplanes. If you want to make a point about tusks, don't confuse them with elephants.

And if you want to make a point about ivory, you need to mention both elephants and tusks. This article is about things on aircraft called "stablilzers". Wikipedia is a reference work - but it is an encyclopedia of attributable information, and not a text book - see WP:NOTTEXTBOOK. As WP:VERIFY puts it, "Verifiability, and not truth." You may believe a whole bunch of sources to be incorrect, but they are still verifiable sources and their PoV deserves to be represented. — Cheers, Steelpillow (Talk) 19:39, 20 June 2012 (UTC)

"Nice find. Barber starts simply. "Longitudinal Stability"? Barbers book is from 1917 when stability was still generally not understood. This is covered by the Culick reference.

Ariadacapo pointed out that: "The "Three’s Company" article’s author mixes up stability and trim". And I pointed out that he was figuring out that the canard fore plane could not be acting as a stabilizer as he wrote the article.

The NASA online "Kindergarten to high school" educational pieces have a few sentences in error and should be corrected. I may be able to contact them. --Stodieck (talk) 07:55, 20 June 2012 (UTC)

It occurs to me that this dispute is not so much encyclopedic as to do with the meaning of "Stabilizer". So I checked out some online dictionaries. General language dictionaries seem split 50-50 as to whether a stabilizer was necessarily at the back. Specialist aero dictionaries were all either non-committal or said that the stabilizer was "usually" at the back, implying that it need not be - and none said that it was. I haven't linked many here because of rampant plagiarism.

Tailplane specifically

"Usually" at the rear

Unspecified location

So my money is on the specialists - who are unanimous in not forbidding a stabilizer at the front. — Cheers, Steelpillow (Talk) 20:50, 20 June 2012 (UTC)

Quick postscript: some reputable sources even talk of a canard in terms of having the "tailplane at the front". I think this comes too late to have any material effect on the outcome of this dispute, so I'm not going to provide any references. But it does go to show how careful we need to be. — Cheers, Steelpillow (Talk) 20:09, 22 June 2012 (UTC)

No this isn't a dictionary. No you didn't achieve consensus before reverting the document for the 100th time. The best encyclopedic reference online, that I can find, is Culick. You haven't responded to this reference or any other provided. Canards are anti-stabilizers and why that is true can be illustrated on a napkin in 5 minutes. You are stating that black is white and that 1+1=5. By reviewing your reversions over the last year it is clear that you literally have only recently mastered the spelling of the word stabilizer, and you still cannot define aircraft stability. You have not answered any number of questions posed to you in these talk sessions, nor can you argue the logic or in the language of the references provided. You have not been learning from the experience of this discourse. The best advice I can provide is that you should permanently stop editing this page. You are not doing anything constructive for anyone, certainly including yourself, by continuing to edit here. --Stodieck (talk) 21:39, 21 June 2012 (UTC)

So - no this isn't a dictionary and I never said it was. If you read what I actually wrote instead of imagining what you disagree with all the time, we might actually get somewhere. Go read what I wrote again. I am not even interested in why you think a many-to-one majority is not a consensus. Unlike you, I read carefully and learn from what I read. Nowhere does Culick state that the term "stabilizer" must never be applied to a foreplane, that is your sloppy interpretation of what he does not say. I am an Englishman and proud of it. We were writing about stabilisers with an 's' before you were born and many people around the world still do. Even though WP:ISE explains this for you and WP:ENGVAR explains that it doesn't matter which spelling is used on Wikipedia, I expect you to ignore or spin them like you ignore or spin all WP:POLICY (and before you throw the OED at me, I am a Cambridge man and am therefore permitted to differ [grin]). I have recently been making a point of spelling it your way as a simple courtesy - didn't you notice that either? I don't answer most of your questions because most are loaded and underlaid by false assumptions and you wouldn't take any notice anyway, any more than you appear to have noticed that I actually support most of what you have to say and we actually differ only on terminology. There is a clue for you here in the title of this article - have you even read that properly? You once threatened (here) that "If we cannot contain [steelpillow's] edits, I will refrain from any other work in the Wiki.". Well, now that you have had your braindump and you still prefer bickering to productive editing, maybe that time has come. Or does your word mean nothing either? — Cheers, Steelpillow (Talk) 20:01, 22 June 2012 (UTC)

Tailplane vs. horizontal stabiliser

It seems that often, especially I suspect in America, it is assumed that the "horizontal stabiliser" is part of the tail and therefore at the rear of the aircraft.

To counterbalance that, one can find the idea that the tail may sometimes be placed ahead of the wing.

For example I have to hand William Green's small-format World aircraft directory, Warne, 1961 and I quote (Page 128), "Canard. An aeroplane of back-to-front layout, with a horizontal tailplane (noseplane) ahead of the wing."

And on the Internet so rather more up to date, "Canard (tail at front)", "Canard-Tail Missiles" (NASA), "a horizontal tail ahead of the main wing" and so on. Some perhaps more reputable, some less so. I found all 3 of these examples in the first 30 hits from a search on both canard and tail, so the idea is quite prevalent.

But I think that explaining that the "tail" can be at the front is confusing to the reader, so it is better to make a different linguistic choice and talk of "foreplane" and "tailplane". Certainly, chopping and changing section titles between the two, as Stodieck has been doing, is also confusing to the reader.

So I vote for keeping this article the way it is as I write and not changing it - unless people think dropping the "canard" from the "canard foreplane" is neater. — Cheers, Steelpillow (Talk) 20:27, 25 June 2012 (UTC) [Update: well it was OK as I left it, but it changed while I was writing that. So how about, "Tailplane" and "Foreplane (canard)"?] — Cheers, Steelpillow (Talk) 20:41, 25 June 2012 (UTC)

This is from the Proceedings of the Royal Society.

In 1904, Bryan & Williams (Bryan & Williams 1904 Proc. R. Soc. Lond. 73, 100–116 (doi:10.1098/rspl.1904.0017)) published an— article on the longitudinal dynamics of aerial gliders, and this approach remains the foundation of all the mathematical models studying the dynamics of airborne vehicles." This quote came from another Proceedings of the Royal Society document; http://rspa.royalsocietypublishing.org/content/early/2009/11/27/rspa.2009.0459.full

This document is also mentioned as the foundation document on longitudinal stability in the Culick reference, which states; "The first paper on the subject of aircraft stability was given by Bryan and Williams (1904) who showed that for the center of gravity fixed relative to the larger surface, the configuration having a smaller surface aft is relatively more stable than that with a smaller surface forward. I suggest you look it up. I don't have an online viewable version of the Bryan & Williams original yet. The knowledge that canard foreplanes are destabilizing has been formally, mathematically, and academically documented, and reduced to practice on both sides of the Atlantic since 1904. The documentation literally starts from the very first academic paper on the subject.

The entire Culick reference is about this subject, not just a line or two. --Stodieck (talk) 22:23, 25 June 2012 (UTC)

I have no problem with that as a verifiable PoV. But that is not what our disagreement is about. As you have been told already Wikipedia is not a text book. Wikipedia puts verifiability above truth. If a different PoV is also verifiable, it deserves equal treatment to any other PoV - that is what Neutral Point of View means. This is where we disagree. All the links in what I have just written are to Wikipedia policies to which, as I say, I have pointed you to before. If you wish to publish material which breaks these policies, you will need to publish it elsewhere. That is all. — Cheers, Steelpillow (Talk) 20:08, 26 June 2012 (UTC)

Probably being overly picky here but the statement "...relatively more stable than that..." does not of itself indicate that a smaller surface forward is unstable - only that it is not as stable; just as I can say that a number n "is less positive than 5" but it does not automatically hold that n is a negative value. GraemeLeggett (talk) 21:11, 26 June 2012 (UTC)

the 1904 Bryan and Williams paper. I skipped the maths to get to the conclusions. The chief conclusion as I understand it is - longitudinal stability can be modelled and aircraft designers should apply it before trying to fly anything. So I had to jump back up to 6. Examples of two Plane gliders p.110 - but I still don't see that it says a foreplane is not a stabilizer. GraemeLeggett (talk) 21:35, 26 June 2012 (UTC)

If you skip the math you may as well skip the reference. This is the first serious mathematical treatment of the subject and still cited to this day along with "Stability in aviation" by G.H. Bryan, Published in 1911. Bryan was a Cambridge prof. This one is available in toto for free here; http://openlibrary.org/books/OL23339633M/Stability_in_aviation This is the document that first separated canards from HSTABs, and marked the end of the prehistory of flight.

Since you two seem to like the kids pages at NASA, here is an Hstab quote; "At the rear of the fuselage of most aircraft one finds a horizontal stabilizer and an elevator". Now stop pulling the HSTAB caption;

http://www.grc.nasa.gov/WWW/K-12/airplane/stablator.html Do notice the capitol K. --Stodieck (talk) 21:49, 27 June 2012 (UTC)

Why a lifting-canard is called a "stabiliser"

This discussion has been moved from Talk:Three lifting surface aircraft#Why a lifting-canard is called a "stabiliser".

Here is my explanation, expanded from one I wrote a while ago. I have greatly simplified the technicalities in order that the non-technical reader will be able to follow the gist of it. Of course there are many technical rabbit-holes one might go down, such as pitching moments rather than lifting forces, downforces instead of lift, variations that behave differently and so on, but the logic of the explanation is sound. Again for the general reader, I use some technically unfashionable terms such as "centre of lift", because they are more intuitive than the current equivalent such as "centre of pressure".

Note also that it only refers to the canard configuration and not to the three-surface configuration. I do not know if anyone has ever called the foremost of three planes a "stabiliser" but I would hope they haven't.

What I mean is, my explanation only refers to the canard configuration.

Any ordinary lifting surface with a conventional aerofoil section is unstable in pitch: any small pitch-up of the front causes the centre of lift to move forwards, increasing the tendency to pitch up, so the thing flips up out of control.

The classic solution to this is to have two surfaces, one behind the other. Each surface has its own centre of lift and the overall centre of lift is now the average position of the two. In steady flight, the two lift forces balance out.

Notice the difference between balance (or trim) and stability. Left to itself, any aircraft in balance will fly straight. But if it is unstable then the slightest gust of wind or internal vibration will tip it off balance and send it twisting crazily out of control.

To achieve stability, we set things up so that a small pitch-up movement will increase the net lift on the rear surface more than the front. This lifts the rear and therefore pitches the nose back down to stabilise (spell with a "z" to taste) the aircraft.

Thus, the craft is stabilised by the relationship between the fore and aft lift components and not by any one surface.

Which surface is the larger and which the smaller is not really relevant to the technical analysis, but it does affect what we call them. From the designer's point of view, the key idea in naming is that the main wing on its own is unstable, it is only by adding the secondary surface that the designer achieves stability.

So it is common enough - as has been referenced by several editors ...

... to call the larger of these two surfaces the "wing" or "main wing", and the smaller the "horizontal stabiliser" regardless of whether it is the fore or aft plane (or if they are of comparable size then we call both of them wings, in tandem).

One may note that the rear surface "wins" with the greater change in lift and therefore in a technical sense it stabilises the action of the forward surface,...

...while the "losing" forward surface is doing its best to destabilise. However, nowhere in the literature is it attested that this forbids a small forward surface to be called a "stabiliser" - everybody understands that adding it allows the craft as a whole to be stabilised.

— Cheers, Steelpillow (Talk) 12:05, 14 April 2013 (UTC)

1- I disagree : longitudinal stability of every configuration aircraft comes from a higher wing loading at front than at rear; there is no difference between a conventional, a three-surface, a canard or a flying wing : lifting (destabilising) surface(s) are ahead, and stabilising wing (or area) is back. There is no specific stability law for two-surface aircraft. First point.

- I agree : the rear surface pitches the nose down to stabilise > the rear wing is stabilising.

- One surface is stabilising, and the other is destabilising. In every aerodynamic book. Of course the stability result matters with each surface characteristics.

- the references I can read are few, and do not stand comparison with professionnal stability analysis (Mark Drela, Hoerner, others)

- this rationale (fore = rear) stands for balance (it would be absurd to tell wich one of the surfaces is balancing the aircraft), not for stabilisation.

2- here is the point of disagreement : in aerodynamics, there is no "main" destabilising wing and no "secondary" stabilising wing ; just front and rear surfaces. This misconception prevents any sound analysis of stability : for example, how to analyse a tandem aircraft, fitted with a foreplane being 0.3 x the rear wing area, each surface lifting half the total weight ? Where are the "main" and the "secondary" wing ? (see the Drela diagram showing the "Lift sharing versus configuration", handling plank, conventional, tandem and canard in the same analysis). Of course, this approach don't work either with a three-surface aircraft (first point). The correct wording would be : "the key idea in naming is that the front wing on its own is unstable, it is only by adding the rear surface that the designer achieves stability. Second point.

3- the rear surface gives a negative pitch moment to the whole aircraft; it does not fight the foreplane only ; the fuselage is destabilising too. Third point.

- increase this "secondary" surface, and enjoy the results : aft tail, a lot of pitch stability ; it works. Fore tail or canard : the aircraft becomes pitch unstable ; it does not work : there is no symmetry. Everybody understands that adding more front surface is destabilising, and authoritative quotes exist telling the same (I found another one in Nasa TM 88354).

- Your explanation does not follow the conventional pitch stability definition : to be pitch stable, the derivative dCm/da (or Cma) has to be negative, that is if a (incidence) increases, Cma must be more negative. The foreplane and fuselage provides a positive pitch moment (destabilising), and conversely the rear surface is stabilising. To get the trim, each surface pitch moment balances the other. To get the pitch stability, when "a" increases, the stabilising effect of the rear wing (Cm -) has to increase faster than the destabilising moment of the front wing and fuselage (Cm +).

- According your rationale, the fuselage, included in the whole stabilising matter and acting like the forewing, is a stabiliser too. This third point proves your isolated approach does not work. Is it somewhere attested in the literature that a fuselage could be called a "stabiliser" too ?

- Last point : we would appreciate some valid quotes telling that, as far as stability is concerned, a foreplane is a stabiliser.Plxdesi2 (talk) 07:59, 15 April 2013 (UTC)

At last I found a book which addresses the subject (though not the terminology): see Barnard, R.H. and D. R. Philpott, D.R.; Aircraft Flight: A Description of the Physical Principles of Aircraft Flight, Pages 303 f.f., which discuss the Stability of Canard Aircraft.

Check out the words used to annotate Figure 11.8 on page 304 where you will see a lifting "foreplane" and an aft-located "main wing".

I should perhaps repeat my initial remark that I greatly simplified the technicalities. These simplifications of course include: no 3-surface discussion, no fuselage discussion, no formulae, no explicit moving of the main wing to rebalance the design. None of these omissions affects the fundamental argument.

In the case of the fore and aft lift dynamics, rather than quote stability formula I simply call it a "relationship between" lift components - a relationship indeed described more precisely by the formula you discuss. In words, the relationship is an inequality between two derivatives: for stability, the change in lift generated by the rear surface must be greater than the change in lift generated by the forward surface. The inequality "greater than" is a mathematical or logical relation.

Plxdesi2 writes, "Everybody understands that adding more front surface is destabilising". And everybody also understands that the designer compensates by adjusting the positions of the surfaces to restore stability. This is a trivial complication I just left out.

The three quotes I linked earlier were those deemed sufficient for that article at the time. ISTR that others were produced during the discussions. It is probably easier to google the others afresh than dig them out of the talk history. For example I see that Patent US6064923 discusses the "canard stabilizer". OTOH, no quotes from authoritative references forbidding a foreplane to be described as a "stabiliser" have ever been produced in these discussions. Plxdesi2 talks about Drela but I have not seen any quotation which explicitly states as much. Where are those references and quotes?

And finally, a couple of points of etiquette (and I know some people do these things elsewhere but that doesn't make them good). Once you have posted a comment, please do not go back and post-edit it without clear visual signs such as "[updated]" or "~~what I didn't mean to say~~", as others may have already read it or even be composing a reply - your changes then create an edit conflict. Also, if you must insert comments in another person's post, please sign each one individually. Many thanks. — Cheers, Steelpillow (Talk) 13:54, 15 April 2013 (UTC)

I apologize for the trouble with the comments, I thought it was easier to read.
Now, about the discussion :

Aircraft Flight, page 304, "lifting "foreplane" and an aft-located "main wing".

Ok, it is a standard description of a canard. There is nothing telling the canard is stabilising.

You said : "I greatly simplified the technicalities. These simplifications of course include: no 3-surface discussion, no fuselage discussion".

Standard stability approach (second point) does not need simplifications, being in fact more simple to understand because it is a general physical rule. So you do not answer the fuselage issue.

I wrote "Everybody understands that adding more front surface is destabilising". You answer : "And everybody also understands that the designer compensates by adjusting the positions of the surfaces to restore stability".

When the area increase is done without modifying anything else, the difference in pitch stability tells the front surface is not the same as the aft surface. The conventional aircraft fly, the canard becomes unstable.

About the patent US6064923, with a "front stabilizer".

The "Stabilizer" is used in this patent to increase the lift/manoeuverability, but, in any cases, to stabilise the aircraft.

A patent extract : "If the aircraft has a stabilizing lift-creating rear surface (horizontal stabilizer), this rear surface may alone be sufficient to stabilize the airplane by countering the pitching moment generated by said front stabilizer by increasing its own lift."

This phrase tells clearly that the aft stabilizer IS stabilizing, "countering the front plane pitching moment" (i.e. destabilising). So, to obtain the balance, the front plane has to be destabilising. The author says "front stabilizer", but also "rear stabilization planes" lower in the text, so "front stabilizer" means (as usual) "front secondary surface" according to your wording. This patent does not say the "stabilizer" is stabilizing, but just the opposite. That is another example showing that calling the frontplane a stabiliser is an unhappy choice.

So, your stability approach is not conventional (first point), "main wing" and "secondary surface" arbitrary distinction is unable to include a canard configuration of wich the foreplane lift is half the total weight (second point), your would-be "simplified" approach cannot include a fuselage into the stabilisation matter (third point), you do not deal with the logical conclusion that the fuselage is a stabilizer according to your thinking, and you have only layout quotes ("stabilizer" described only as a front secondary surface) to oppose several authoritative (Is Hoerner an "amateur"?) conventional aerodynamic stability quotes, all saying the foreplane is a destabilising surface. In english, like in french, "stabiliser" means "stabilising", I suppose. Or, as the negative lifting tail of the P-180 is "sometimes" called a "lifting surface", why not call a destabilising surface a stabiliser ? Plxdesi2 (talk) 17:51, 15 April 2013 (UTC)

As far as I am concerned, my approach is perfectly conventional. That is the single issue at the heart of this discussion - we agree on the technical analysis, we just disagree which words to describe it with. If you choose to pick issues with Barnard & Philpott's terms, you really will need cast-iron references. Also, your quotation from Hoerner is not relevant - it discusses the Curtiss Ascender, which had an unusual floating foreplane that nobody would describe as a stabiliser (and indeed Jones, in US Fighters, Aero, 1975, regards it as "not a true canard"), but that obviously does not apply to all canard types. There is a big jump from saying "in itself it acts to destabilise" to "it is never a stabliliser" - if I add a surface to stabilise an unstable design (adjusting the main wing position accordingly, of course), it is natural to call it a "stabiliser". You do not agree with that, but Wikipedia is about verifiability not truth and there is sufficient literature attesting to that form of words. There is also plenty of literature saying that in itself it acts to destabilise, but I ask yet again - where is the literature which takes the extra step and says explicitly that because of that it is ~~the~~ wrong to call it a "stabiliser"? — Cheers, Steelpillow (Talk) 19:48, 15 April 2013 (UTC)

"your quotation from Hoerner is not relevant - it discusses the Curtiss Ascender, which had an unusual floating foreplane that nobody would describe as a stabiliser".

It would be better to use the Hoerner book rather than the comments on that book. The canard surface of the Curtiss is a lifting all moving surface, not a floating (non lifting) surface : Stability Contributions, page 11-30 : "to trim the airplane, say to Cl = 0.5... the lift of the canard coefficient is between 0.8 an 0.9." The figure 34 gives the lift distribution along the canard span (tested in full-scale Tunnel). It was a small canard surface (10 % of the wing), so the positive pitching moment was insufficient to trim the aircraft at low speed ; the foreplane area was later increased. This Hoerner quote, and the other one about "Delta Canard" page 11-33 are relevant. By the way, thanks to Mr Jones (and others), we have another Canard type : the "True canard class", fiffed with "fixed forward control surfaces". Accordingly, the conventional aircraft with an all moving stabiliser are not "true" conventional aircraft.

" but that obviously does not apply to all canard types".

Your visual approach prevents you to see the generalized law of stabilisation (Cm- versus Cm+), no matter the configuration.

"if I add a surface to stabilise an unstable design (adjusting the main wing position accordingly, of course), it is natural to call it a "stabiliser".

Once again, you mix geometrical considerations ("main" wing and "small" wing called a stabiliser) with stability considerations, when the front wing is destabilising and the aft wing stabilising, no matter their respective areas. This arbitrary "main and small" surfaces distinction stands only for conventional or canard designs, not for a larger foreplane of a canard layout, of wich you cannot say where is the "main" wing. This is the result of a visual approach, not an aerodynamic one dealing only with pitching moments.

A canard, being the same size as an aft tail, may be "sometimes" called a stabiliser by visual symmetry. We would like some quote (from an aerodynamic specialist) telling that a canard is stabilising. Plxdesi2 (talk) 09:56, 16 April 2013 (UTC)

Perhaps Jones has it wrong about the Ascender then, or perhaps Hoehner does, I don't know or care. But if you are still worrying about my technical understanding and asking for a technical quotation then you have not yet grasped the point. This is about the words used, not about the technical logic. The title of this section makes this plain: "Why a lifting-canard is called a 'stabiliser'". But let me see if I can make it even plainer:

"A foreplane gives a stabilising moment" - No, the references are clear that this is technically wrong.
"A foreplane is sometimes called a 'stabiliser'" - Yes, the references are clear that this description does get used authoritatively.

If the world is in the habit of mixing geometrical terms with stability terms then, right or wrong, Wikipedia should respect that. There is no more to say. — Cheers, Steelpillow (Talk) 18:50, 16 April 2013 (UTC)

"Perhaps Jones has it wrong about the Ascender then, or perhaps Hoehner does, I don't know or care".

As the quote has another meaning that wanted, and does not serve your reasoning any longer, it becomes of no value. You did the same with Drela (newsgroup text : not an authoritative reference). I would like to compare Jones books, if exist, with Hoerner "reference" books. It seems you cite or talk about some quotes without reading them in detail (Patent US 6064923, Garrisson paper, Hoerner about Curtiss Ascender).

"A foreplane gives a stabilising moment, this is technically wrong."

I agree. One can notice this sentence is inconsistent with a lot of previous sentences (from the talk) :

"because the Wright Flyer's canard did not provide stability, does not mean that none do",
"Showing that in one design a canard is destabilizing does not show that it is destabilizing in all."

means clearly that a canard may be "sometimes" stabilising".

"It's a case of taking an unstable wing and adding a canard surface to stabilise the aircraft."
"To me, an additional surface that stabilises any craft is a "stabiliser".
"And here's a link which explicitly states that "Some airplanes ... get their stability from a much smaller wing (called a canard) in the front."
"the smaller canard surface is in practice introduced in order to stabilise the craft."

means the canard is used for stabilisation.

"it is crystal clear that a canard foreplane may act as a stabilizer"

may be called, YES, may act : NO

"the foreplane acts to help stabilise the craft by moving the centre of lift forward."

if "stabilise" means stabilisation, it's false. Here "stabilise" means balance.

"If the world is in the habit of mixing geometrical terms with stability terms then, right or wrong, Wikipedia should respect that. There is no more to say."

No more to say ? When a term has several meanings, define these meanings is mandatory. That's what I did in "Canard" introduction, telling first it means aircraft or foreplane. I did the same in Pusher configuration, splitting pusher (engine/proppeller) from pusher (aircraft). I'am doing the same in [Three surface (aircraft)], to correct some misunderstanding induced by "three lifting surface". That is not yet done is "stabilizer" article.

It would be logical to write that "stabiliser" means first a "tail surface", sometimes a "foreplane" (done) ; to write also that balance and stabilisation are different matters, that "balancing surface" do not mean "stabilising surface", and to move the "Foreplane canard" part to "Canard (aeronautics)" article. Plxdesi2 (talk) 14:14, 17 April 2013 (UTC)

What I mean is, I have nothing more to say in this particular discussion about Why a lifting-canard is called a "stabiliser". — Cheers, Steelpillow (Talk) 09:14, 19 April 2013 (UTC)

Canard foreplane stability

Moved to Canard (aeronautics)

Canard : to be or not to be (in Stabilizer)

Following the discussion about "canard as stabiliser", it may be concluded that, although it is sometimes called stabiliser, a canard is generally aerodynamically described as a destabilising surface, so being not logically included here. It seems that the section "Canard foreplane" would be better moved to Canard (aeronautics) under the title, for example, "Canard effect on the stabilisation".
What is your idea about this ?Plxdesi2 (talk) 15:52, 17 April 2013 (UTC)

Agree. Good work aligning up the sources regarding the denomination. Ariadacapo (talk) 16:23, 17 April 2013 (UTC)

I Disagree. People will read of a "canard stabiliser" and want to know more. They are as likely to turn to the Canard (aeronautics) article as to Stabilizer (aircraft), so to make these articles readable, both need to summarise the issue. It may be that some of the section's content can usefully be moved or copied across, but I haven't looked that deep. The section heading and basic discussion should stay. But I will second that you are doing much good work, and not just in organising references. — Cheers, Steelpillow (Talk) 18:21, 17 April 2013 (UTC)

A stabiliser is a component of an aircraft, conventional or canard > in case of "canard stabiliser", the logical search seems to be towards "canard" (aircraft) first. But my intent is not to vacuum clean the "stabilizer" article, of wich the "canard called a stabiliser" makes part. Just put the infos (especially stabilisation) at their due place. Plxdesi2 (talk) 19:30, 17 April 2013 (UTC)

Taking a closer look at the section, most of it is discussing how stability can be achieved with a canard "stabiliser" and so is relevant to this article. The last two paragraphs are not really relevant and I'd suggest they should be moved across or deleted. Looking next at the Canard (aeronautics) article, use of the term "stabliser" only ever applies to a lifting-canard, so I'd suggest that section needs a new subsection, called say "Stability", and with similar content but adapted for the focus of the article. Does that make sense? — Cheers, Steelpillow (Talk) 21:05, 17 April 2013 (UTC)

I moved to Canard article all the stability considerations specific to canard aircraft, with some adds an ref. Plxdesi2 (talk) 19:04, 18 April 2013 (UTC)

Three-surface foreplane

This section has just been added. I don't think the foreplane of any 3-surface design has ever been called a stabiliser, has it? Or was the Voisin example discussed ever called that? Otherwise, this section has no place in an article on stabilisers (For those who care, this is a neat reversal of recent editorial roles, where elsewhere I have been arguing for describing some foreplanes as "stabilisers"). — Cheers, Steelpillow (Talk) 10:28, 18 April 2013 (UTC)

Sorry for the misleading wrong title ; the correct wording being "three surface aircraft".

Because of the reasoning to call "stabiliser" a secondary surface, including canard foreplane, I think one has to deal with "secondary surfaces" of every layouts, including three-surface, giving the different names (stabilizer, elevator, balancer) and the associated function. Those early three-surface (Voisin, sure ; Curtiss, not sure) had tailplanes without elevators, so do not belong to the "tailplane" part of the text, describing a stabiliser as a stability AND control surface. So I added this section.

"Foreplane of 3-surface design called a stabiliser"

In Les hydros Farman [2], "le stabilisateur avant sera supprimé en cours d'année" = the front stabilizer will be removed during the year". As the english term is elevator, I put the french term rather than stabiliser into the text. This is another example of how to call "stabiliser" a non stabilising surface.

There is no reversal ; I do not discuss "stabiliser" as a term (although better to say canard), but stabiliser as stabilising device.

Thanks for your remark. Plxdesi2 (talk) 15:28, 18 April 2013 (UTC)

Was intrigued by question of what the French call an elevator, going by the French Wikipedia it isn't stabilisateur. The word is there as in phrases like "empennage (stabilisateur horizontal et derive)" where it appears to mean stabilizer and in the Roe Triplane 4 where it seems to mean the same (going by its application to triangular in the description of the Triplane's tailplane). Not very rigorous at all, the article lack specific cites and most seem translated from the English or give English language sources. GraemeLeggett (talk) 11:46, 19 April 2013 (UTC)

In French, elevator is gouverne de profondeur (depth control device). The stabilizer (entire device, whether movable or not) is called empennage horizontal, stabilisateur, or even plan horizontal stabilisateur depending on the author’s mood or background. Trim tab is compensateur. I have a reference at hand if you need. As with English, in old documentation (especially when written before notions related to stability were formalized) the nomenclature tends to be highly unreliable.Ariadacapo (talk) 08:08, 21 April 2013 (UTC)

In French, the horizontal tail is called "empennage" (without adding "horizontal", because the vertical fin is never called "empennage vertical" but "dérive") or "stabilisateur or simply "stab" (frequent). The elevators are called "la profondeur" or "les volets de profondeur" (pitch flaps).Plxdesi2 (talk) 16:35, 22 April 2013 (UTC)

Voisin 1908 configuration

"The Voisin was more precisely a tandem lifting layout (wing and tail)"

Clarify :"More precisely" → Was the center of gravity positioned between wing and tail?

Yes, see web images. It is a tailwheel gear, the main gear is about mid-chord front wing, the CoG placed about the trailing edge of the main wing : the rear wing (tail wing) is actually loaded (note the cambered rear airfoil, as much as the wing).

"With a foreplane that was neither lifting nor stabilizing ; it was called an "équilibreur",^[1] ("balancer"), and used as a pitch control and trim surface".

Clarify : If the équilibreur is used to balance (trim) and control (braquer vers la montée→ deflect towards climb position), then it is necessarily used as a lifting surface.

Every control or trim surface is momentarily lifting. The Voisin foreplane (as AEA-Curtiss aircraft) was a control-trim surface, not mainly lifting. See in flight images showing the foreplane in neutral or down incidence. The Voisin is a reversed 3 surface : pitch control at front instead of rear, rear lifting tail instead of front lifting canard. — Preceding unsigned comment added by Plxdesi2 (talk • contribs) 08:15, 23 April 2013 (UTC)

Thank you for these explanations! To me, "control" (ability to change equilibrium) and "trim" (equilibrium) are related but very different, so "control-trim" sounded a little unclear. I think the article is much clearer now. Ariadacapo (talk) 11:47, 23 April 2013 (UTC)

References

^ Gabriel Voisin, Mes 10.000 cerfs-volants (My 10,000 kites), page 166 : "et je m'apprêtais à tirer sur mon équilibreur... puis il braqua son équilibreur vers la montée."

Stabilizer with or without control surfaces

"Stabilizer" has two meanings : as horizontal tail or tail, it is the rear tail assembly. As structural part, it may describe the fixed part of a conventional tail. This second restrictive definition prevents to deal with balance and stability considerations, because the whole tail assembly (and not only the front "stabilizer") is involved in. There is no stability without elevator, because stabilization needs first a balanced trim, given by elevator/trim-tab unit. That prevents also to describe (and to understand as well) the all-moving tail variant, of which there is no fixed part nor would-be specialized stabilizing OR controlling parts. In the restrictive separate "stabilizer" approach, a full moving tail, lacking "stabilizer", may be understood as unable to stabilization effect.
In the previous text, a reader was barely able to know if the "stabilizer" term had the first or the second meaning. So this dual meaning was to be cleared first. Accordingly, the article may describe the whole role of a tail, balance, stability and control. Plxdesi2 (talk) 11:55, 4 May 2013 (UTC)

Canards

I have reverted a series of edits, initiated by User:Stodieck (talk), to the section on Canard aircraft. These edits are highly contentious and need to obtain consensus first. — Cheers, Steelpillow (Talk) 18:16, 20 July 2013 (UTC)

Stabilators

Cagliost In your edit dated 18 October you inserted statements about:

1. some light aircraft having an all-moving stabilator rather than separate stabilizer and elevator, and

2. supersonic aircraft having stabilators to avoid unacceptable drag.

You cited a NASA educational website as the source. I have read the NASA website and I can find nothing to support the above 2 items of information. Am I missing something hidden somewhere in the cited source? Please check your edit. Thanks. Dolphin (t) 08:10, 18 October 2022 (UTC)

[1] Gabriel Voisin, Mes 10.000 cerfs-volants (My 10,000 kites), page 166 : "et je m'apprêtais à tirer sur mon équilibreur... puis il braqua son équilibreur vers la montée."

[1]