Talk:Stabilator

slab tailplane

This article mentions the flying tailplane but does mention the slab tailplane, which is different, I beleive. If I were more sure of the distinction I would add it. Can someone here please help? 165.91.64.181 (talk) 18:29, 14 April 2009 (UTC)RKH

The present (24 Oct. 2007) version of this article cites the Mooney M20 series as an aircraft type which utilizes a stabilator. This is not correct, so I am deleting it (I will replace it with a citation of the Cessna 177 series). The confusion perhaps arises from the Mooney pitch trim approach: the entire empennage (horizontal tail, vertical tail and tailcone) is pivoted just ahead of the horizontal stabilizer. Thus when the trim tab is actuated, the entire tail unit is pivoted to increase or decrease the horizontal tail's angle of attack. However, this is the only movement of the horizontal stabilizer, so it is not a stabilator in the sense that a pilot would make that movement every time he wished to change the aircraft's angle of attack. I hope this doesn't cause confusion.Raymondwinn 07:49, 25 October 2007 (UTC)

Boeing 747 tailerons

I saw a parked Boeing 747 with its two horizontal stabilizers at markedly different angles of attack, and subsequently asked a retired airline pilot now involved in pilot training about this. He explained that:

"The Boeing 747 use both tailerons and ailerons to provide roll control, as otherwise the roll response is too slow; before ailerons alone could start to roll the fuselage, the wing tips would have to flex a long way."

So far I have found no citations on the internet to confirm this statement. Relevant Boeing training material or other documents should confirm this. Does this apply to other large aircraft? If so which? Can anyone help? GilesW (talk) 18:17, 8 May 2010 (UTC)

"All flying" or "all-flying"?

The use of the phrase "all flying" is confusing (eg "All flying tailplanes were used from early times ..."), and in the literature seems to be interchangable with "all-flying". IMHO the use of "all flying" should be limited, and replaced with "all-flying" in most cases. Opinions? Chalky (talk) 03:54, 2 February 2011 (UTC)

A stabilator can also be mounted in front of the main wing

Show me your citation for this statement --Stodieck (talk) 03:40, 3 June 2012 (UTC)

I don't think one is needed. We know that a canard foreplane can act as a stabilizer, we know that a stabilizer can also act as an elevator, the refore a canard foreplane can act as a stabilator. Rather, you need a reference to support the idea that the normal rules of language do not apply. Or, if you think that in spite of your PoV being outvoted, an all-flying canard is different and can never act as a stabiliser, then you will need to reference that. Until then, you need to stop your destructive edits of other contributors' material. Just for starters, googling "all flying canard" collects 5,910 hits. Go to it. — Cheers, Steelpillow (Talk) 11:18, 5 June 2012 (UTC)

IF you wish to challenge the point, you can add a Citation Needed tag or similar - see here for more options. But don't summarily delete other editors' work. — Cheers, Steelpillow (Talk) 11:26, 5 June 2012 (UTC)

Lead definition

"A stabilator (stabilizer-elevator)... is a single aircraft surface..."

What "single" means ? one wing, or a wing with 1 component only ? if it's the answer, it's wrong : a stabilator has usually 2 geared parts : main and tab (anti-servo tab) or main and elevators (as in airliners).

"...that combines the functions...

the functions are not described.

"...usually performed by a separate tailplane (horizontal stabiliser) surface and elevator (horizontal control surface) hinged to the back of the tailplane."

"Tailplane" and "horizontal stabiliser" means usually a conventional tail, including fixed part and movable part (elevators). So, how to "combine", that is to say put together a fixed part, a movable part (elevators) and another movable part (elevators again) ? One has to guess that, in this sentence, "tailplane (horizontal stabiliser)" means "fixed part" of a H tail, not consistent with tailplane usual meaning.

The understood message (functions combination) may be : the fixed part is stabilising ; the movable part is for control. That is aerodynamics for children ; the present wording is technically misleading.

The sentence is a mix of descriptive considerations (horizontal stabiliser, tailplane, elevators) with function considerations.

The lead would better have a descriptive (geometric) part giving the essential feature of an all-moving tail (a fully movable surface), and a function part giving the essential aerodynamic features (efficiency, hinge moments, wide CoG travel), and some references. Plxdesi2 (talk) 08:50, 3 May 2013 (UTC)

OK, so you went ahead. I have to say that to the casual reader that is really unreadable techno-babble, introducing advanced ideas and with poor grammar. The lead really does need to be understandable by children. Can I suggest this:

"An aircraft stabilator (stabilizer-elevator) is a horizontal surface that combines the separate fixed and movable parts of a conventional tailplane into a single movable surface.

"It combines the functions of both horizontal stabilizer and elevator, performing all the functions of longitudinal pitch balance, stability and control.

Other terms for a stabilator include all-moving stabilizer, all moving tailplane, all flying tail, flying tail and slab taiplane."

— Cheers, Steelpillow (Talk) 10:26, 3 May 2013 (UTC)

Sorry for the poor grammar, not my tongue as you know. I thank you to correct it, please.

"...into a single movable surface."

All the stabilators I know of have at least two surfaces : main and tab, or main and elevators (airliners). The anti-tab is not just a small point, it is an essential part of the concept. The anti-tab moves in the same direction as the stabilator, but with increased travel : definitively not a "single" surface. A suggestion : a single movable unit.

"It combines the functions of both horizontal stabilizer and elevator"

I would like to know if the term "horizontal stabilizer" usually includes the elevators : yes, "sometimes" or not.

"...all the functions of longitudinal pitch balance, stability and control."

Stick force requirement is lacking ; it is one of the main reasons to install stabilators in both large and small aircraft.

"Because it involves a large moving surface, a stabilator can allow the pilot to generate greater pitching moment with little control force."

What allows more lift with less effort is not the "large moving surface", but the large balanced moving surface.

Airliners. "...adjustments are handled by adjustable (in angle of attack) horizontal stabilizers".

AoA or incidence : the pilot do not control the AoA but the pitch control surface incidence. Plxdesi2 (talk) 13:13, 3 May 2013 (UTC)

Tailplane, H tail, H stabiliser, definitions

In Priceton edu [1] :

A "tailplane", also known as "horizontal stabilizer" (or horizontal stabiliser), is a small lifting surface located on the tail (empennage)... The tailplane serves three purposes: equilibrium, stability and control.

"The tailplane comprises the tail-mounted fixed "horizontal stabiliser" and movable elevator."

In the free dictionary [2]

"Tailplane" - the horizontal airfoil of an aircraft's tail assembly that is fixed and to which the elevator is hinged

"horizontal stabiliser" - idem tailplane

"Horizontal tail" - the horizontal stabilizer and elevator in the tail assembly of an aircraft.

In Dictionary.com [3]

"Horizontal stabilizer" : the horizontal surface, usually fixed, of an aircraft empennage, to which the elevator is hinged. Also called, especially British, tailplane.

In Daroll Stinton, The design of the aeroplane

Tail = horizontal tail = stabiliser = tailplane + elevator

In Roskam, "Airplane Design", part III, layout design, empennage

Empennage = horizontal tail = horizontal stabilizer = stabilizer

To be continued Plxdesi2 (talk) 22:15, 3 May 2013 (UTC)

More accurately, Collins English Dictionary (as cited in Freedictionary) gives tailplane as "a small horizontal wing at the tail of an aircraft to provide longitudinal stability Also called (esp US) horizontal stabilizer"

And then its the thesaurus ("Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc") which gives those definitions.

Dictionary.com is "Based on the Random House Dictionary, © Random House, Inc. 2013." GraemeLeggett (talk) 16:04, 4 May 2013 (UTC)

Oxford Dictionaries Pro gives "tailplane" as "noun, British a horizontal aerofoil at the tail of an aircraft. and one of the examples of use is "single-piece all-moving tailplane."

Stabilator "a combined stabilizer and elevator at the tail of an aircraft." but no examples

OED gives an example "On some aircraft the stabilizer and elevator are combined into one surface, referred to as an all-moving horizontal tail or stabilator." GraemeLeggett (talk) 16:15, 4 May 2013 (UTC)

In Charles H Gibbs-Smith, Aviation, Glossary : " Stabiliser : Any aerofoil used to provide stability".

"OED ...combined into one surface" : both true (no separate elevator) and false (separate anti-tab or elevators (airliners)). So, it maybe that "single surface" describes the one piece unit distinctly separated from the fuselage (Piper aircraft layout, Cherokee, Malibu etc...). Plxdesi2 (talk) 07:44, 6 May 2013 (UTC)

I don't think you can describe the OED as incorrect. It records usage and meanings. GraemeLeggett (talk) 09:27, 6 May 2013 (UTC)

I find it really frustrating when the authoritative use of words, such as "stabilizer", varies and is often technically incorrect. In the above example, Princeton even manages to contradict itself. A form of words I have sometimes used is along the lines of, "Usage of these terms can vary. In this article, we use "stabilizer" to mean the foremost surface (usually fixed), "elevator" to mean any secondary movable surface and "tailplane" to mean the whole assembly. A single movable surface carrying out both functions is here called a "stabilator." [edit for preferred definitions, personally I'm not fussy]. That way, we can at least give a technically accurate and unambiguous analysis. — Cheers, Steelpillow (Talk) 19:03, 6 May 2013 (UTC)

What the Americans call a 'stabilizer' the rest of us call a 'tailplane', and thankfully, we all of us call the hinged flap at the back an 'elevator'. The 'tailplane' is so-called in contrast to the 'mainplane', aka the wing. The other name for canards is 'fore planes'.

They are called 'planes' BTW because in the early days of aeroplane flight they resembled flat surfaces, i.e. a plane. — Preceding unsigned comment added by 2.24.216.123 (talk) 16:04, 6 July 2014 (UTC)

All-moving tail

Google search : Stabilator : 144 000 occurences - all-moving tail : 73 600 000 occurences
All-moving tail  : in Abzug - Larrabee Airplane stability and control
Fully-movable tail : in Hoerner Fluid Dynamic Lift Plxdesi2 (talk) 09:01, 3 May 2013 (UTC)

Helicopters and stabilators

"Stabilator" misfunction is given as the cause of a prototype Blackhawk crash in 1978[4] but helicopter stabilators do not seem to be addressed in the article.GraemeLeggett (talk) 16:48, 4 May 2013 (UTC)

Airliners

"Most modern airliners adjust the tailplane angle of incidence to trim during flight as fuel is burned and the center of gravity moves."

Maybe the tailplane adjustment main cause is not the CoG movement but the important pitch moment variation caused by wing camber modification (flaps) and by power setting (engines thrust lower than drag > positive pitch moment).

"These adjustments are handled by adjustable incidence horizontal stabilizers. However, such adjustable stabilizers are not the same as stabilators; a stabilator is controlled by the pilot's control yoke (or stick), when an adjustable stabilizer is controlled by the trim system."

Do that means a stabilator is a flight control system and an adjustable stabilizer is a trim system ?

If "modern airliners" means computer controlled aircraft, I don't know the difference between adjustable stabilizer and stabilator. The pilot give an input order (up or down), then the computer moves the rear part (elevator) of the stabilator and, at the same time, automatically adjust the incidence of the front part in order to reduce the elevator deflection relative to the front part (to keep max travel and reduce drag). I have to check this point. Plxdesi2 (talk) 08:53, 7 May 2013 (UTC)

Airbus "auto trim" function [5] or "No requirement to change pitch trim for changes in airspeed, configuration, or bank up to 33 degrees." [6]. Plxdesi2 (talk) 10:08, 7 May 2013 (UTC)

My understanding has always been that an adjustable stabilizer has a conventional elevator hinged to the back of it. The pitch control system acts on the elevator only, while the trim system acts on the whole tailplane (i.e. directly on the forward stabilizer section and hence indirectly on the elevator also). But as you are by now aware, I am not always right! — Cheers, Steelpillow (Talk) 15:33, 7 May 2013 (UTC)

Seems to be the case with the 1928 "American Moth". GraemeLeggett (talk) 18:16, 7 May 2013 (UTC)

American Moth, Me 109 and Piper-Cub (if I remember corrrectly) had a conventional tail, the pitch trim acting on the forward section, forming with the elevators an adjustable stabiliser, ok. Coming back to all-moving tail, modern airliners, do you mean that "adjustable stabilizer controlled by the trim system" applies to computer controlled aircraft ? Plxdesi2 (talk) 20:57, 7 May 2013 (UTC)

The grammar of the sentence makes no such limitation, and I don't think any was intended. As a discipline, modern systems engineering treats the pilot as part of the system, just as much as any mechanical component. Whether the adjustment is manual or computer-controlled, it is still a trim system. I assume that is the meaning here also. — Cheers, Steelpillow (Talk) 09:36, 8 May 2013 (UTC)

In the context of an all-moving surface, I wonder if there is also a difference between a stabilator with added movable trim tab, and a truly monolithic stabilator surface which also adjusts for trim. I have not thought through the naming implications, but as I don't recall ever seeing a stabilator trim tab, it may not matter anyway. — Cheers, Steelpillow (Talk) 09:43, 8 May 2013 (UTC)

All-Moving, Full-Flying, Vertical Stabilizer/Tail

I see no mention here or elsewhere an Wikipedia about one-piece vertical stabs/rudders/tails/tailfeathers. These were used extensively in early aviation and somewhat today. Also a full-flying/all-moving tail gives me an image of an entire tail assemblage pivoting in front of the tail such as an early Demoiselle. — Preceding unsigned comment added by Flight Risk (talk • contribs) 16:05, 15 November 2018 (UTC)