Instabilité Typhoon vs Rafale

[DEFA550]

La fleche du Rafale est 2/3* dessous les 50.

Le plan 3-vues donne 50 degrés, la photo 49 degrés. Sauf que la photo est prise légèrement par l'arrière, ce qui ouvre l'angle mesuré et diminue artificiellement la flêche de l'aile.

[Laurent]

Sur le site de Dassault on peut voir une vue en 3D du rafale. Si on mesure l'angle grosso-modo avec un rapporter sur l'écran on obtient quelque chose de l'ordre de 47*. (cliquez vue de dessus) ;) :arrow: http://www.dassault-aviation.com/media/anim3d/rafale.cfm#

[DEFA550]

A priori, le plus précis qu'on puisse trouver c'est le plan 3-vues. D'un autre côté, ces plans peuvent avoir été manipulés volontairement pour masquer certaines données, si bien que le plus sûr est encore de se baser sur des photos pour confirmer telle ou telle source.

Dans tous les cas, la flêche ne dépasse pas 50 degrés et on pourrait aller jusqu'à dire qu'elle est de 49 +/- 1, ou 48 +/- 2 pour ne froisser personne. La précision est plus que suffisante pour nos maigres moyens.

[Dada4]

Mouai!! achement précis les plans 2D !! LOL!

Plan dassault:

http://dada4.free.fr/fleche-C-dassault.jpg

Plan Russe du B:

http://dada4.free.fr/fleche-B-popov.jpg

Ca fait belle lurette que je ne fait plus confiance au ,soit disant, plan 2d des avions!! Rien ne vaux le copiage sur les tophes et un certain bon sens!

y'en bien qui , qui détermine l'AOA du rafale de cette façon là.

[azaazel]

salut pourquoi est ce si important 48° ou 50° ca change quoi svp ?

[TMor]

salut pourquoi est ce si important 48° ou 50° ca change quoi svp ?

Parce qu'il est généralement admis qu'une aile dont l'angle est moins élevé a un meilleur rapport portance sur trainée, et est donc une aile meilleure en faible vitesse.

[DEFA550]

Ca fait belle lurette que je ne fait plus confiance au ,soit disant, plan 2d des avions!! Rien ne vaux le copiage sur les tophes et un certain bon sens!

Il y a quand même une différence entre un plan publié par Dassault et un vague dessin...

Quant aux photos, il est vrai qu'on ne peut pas à la fois réfuter l'angle de flêche obtenu de cette manière et soutenir une thèse sur l'angle d'attaque par le même biais alors que les conditions sont bien moins favorables.

[TMor]

C'est pas off-topic, on va parler un peu d'instabilité, et de contrôl du "pitch" (incidence ? assiette ? mouvement en tangage quoi !).

Petit plongeon dans le pourquoi et le comment des écoulements tri-dimensionels tant étudiés par Dassault-Onera... (ou pourquoi croire les théories de Fonck sur Canards/LEX)...

Désolé, c'est en anglais, et je n'ai pas le temps de traduire ce truc. En plus, c'est très très dur à suivre, à cause du vocabulaire auquel on n'est pas tous accoutumés. Bon courage à ceux que ça intéresse.

Ces passages ne sont que des extraits d'introductions tirés de documents différents. J'ai mis des petites références.

Doc0 -ONERA- AIAA

Breakdown vortices

The development of extremely maneuverable fighter aircraft and missiles has resulted in flight regimes which involve high angles of attack, raising interest in the study of three-dimensional separated flows. The delta wing design has become the prominent configuration used by combat aircraft manufacturers worldwide such as Lockheed's F-117, Dassault's Rafale, Eurofighter, and Boeing's design for the Joint Strike Fighter. A distinguishing feature of the delta wing flow field, at moderate to high angles of attack, is the formation of several vortical structures on the leeward surface. These vortical structures result from the rolling up of the viscous flow sheet previously confined within the boundary layer attached to the leeward surface.1 The most prominent of these vortical structures, which form along the sharp leading edges of delta wings, are called leading-edge vortices. The axial velocity component in the leading edge vortex core can reach values as high as three times the freestream velocity. The vortex dynamics are influenced by several delta wing parameters which include sweep angle, leading-edge geometry, wing thickness, as well as freestream conditions and angle of attack. These leading-edge vortices produce between 30% and 60% of the total lift at high alpha. Therefore, delta wings have a significant advantage in lift forces when compared with other wing designs. However, at high alpha, these well-organized leadingedge vortices often experience a sudden disorganization, known as vortex breakdown, which reduces the lift generated.

// Interessant, l'avantage des ailes delta face aux autres design... Les vortex de bords d'attaque sont si puissants qu'ils sont à l'origine de 30 à 60 % de la portance totale aux grands angles d'attaque. Malheureusement, à une certaine dose d'alpha, les vortex se déglinguent et la portance rechute... Quelqu'un a plus d'explications ???

Doc1 -NASA-

Close-coupled-canard

Many modern aircraft, both operational and experimental, utilize canards for maneuver control and improved aerodynamic performance. In addition to providing positive pitch control, influence of canards on wing aerodynamics can often result in increased maximum lift and decreased trim drag. Canard configurations have inherently different stability and trim characteristics from conventional tailplane configurations. However, with the capability of present-day automatic control systems, the reduced or even negative static stability of a canard configuration can lead to improved aircraft agility and maneuverability.

Aircraft using canards as primary pitch control surfaces often require large canard deflections. For example, the X-31 aircraft has a long-coupled canard which deflects between + 20 and - 70 deg for pitch and recovery control.' For closely coupled canards, a deflected canard has a more significant effect on the canard-wing aerodynamic interaction and, consequently, the aerodynamic performance of the aircraft. The NASA X-29, SAAB Viggen, and SAAB Gripen are three examples of fully integrated close-coupled canard configurations. The X-29 has a forward swept wing and a movable close-coupled canard which is the primary pitch control surface as well as an integral component in the active control system.* The Viggen has a close-coupled fixed canard for highperformance aerodynamics, while its successor, the Gripen, utilizes movable close-coupled canards to obtain maximum lift in maneuvering, maximum lift-to-drag ratio in cruise, and even nose-down pitching moment during short-field landing roll-0ut. Proper utilization of canards in present and future aircraft requires an accurate understanding of their influence on the flow structure about the wing.

At moderate angles of attack, for canards or wings with sharp leading edges, the flow separates at the leading edge due to the adverse pressure gradient on the leeward side. A free vortex sheet is formed which rolls up over the upper surfaces of the canard or wing. If the vortex is sufficiently strong, secondary, and in some cases, tertiary separations may result.

The flow structure of highly swept or delta canard-wing configurations is characterized by a canard downwash which modifies the wing flowfield and an interaction between the canard and wing vortex systems. The inboard wing flowfield is often dominated by the canard downwash, and the outboard is affected by the subsequent change in wing leading-edge vortex formation and the canard-wing vortex interaction. Details of a typical coplanar canard-wing flow structure are given in Ref. 4. Deflecting the canard can drastically change the canard-wing aerodynamic interaction. For example, the stronger canard downwash and modified canard trailing-edge location of a positively deflected canard will significantly change the wing flowfield relative to that of the coplanar canard case.

Additional flow features contributing to the complex flow structure of deflected canard configurations in the transonic regime include secondary, trailing edge, and tip vortices, as well as regions of shock-induced or other boundary-layer separations. In addition to off-surface crossflow shocks, a strong primary vortex often causes the formation of a strong secondary vortex which significantly affects the surface pressures near the canard or wing leading edge. Furthermore, trailingedge and tip vortices can interact with the leading-edge vortex as it convects downstream. If these vortices are formed on the canard, then further interaction with the wing vortex system occurs. The boundary-layer separation due to a high angle of attack, or induced by a strong recovery shock, is also influenced by the presence of these vortices.

// Les canards "à la Rafale" ont un meilleur impact sur les performances aérodynamiques de l'avion que ceux "à la Typhoon". Tels qu'ils sont, ils servent à maximiser la portance en manoeuvre, améliorer le rapport portance/trainée en croisière, etc.

Doc 2 -Israel Aero Institut- AIAA

Close-coupled-canard

It is by now well-established that higher lift coefficients can be achieved on slender wing configurations by the use of aerodynamic means that stabilize the free rolled-up vortices and/or delay vortex breakdown at high angles of attack. At increasing angles of attack, the lift due to these vortices is increasing as long as the rolled-up vortices remain coherent and stable. Such enhancement of the leading-edge vortices is obtained by the close-coupled wing-canard configuration. The canard vortices interact with the wing vortices in such a way as to stabilize the free rolled-up vortices to higher angles of attack and also delay the vortex bursting. This results in the extension of the useful range of the angles of attack enabling higher values for the maximum lift coefficients for the wing-canard configurations. Similar effects of enhancing the coherence of the free rolled-up vortices and delaying vortex breakdown is also achieved by various devices such as leadingedge extensions (LEX), "saw tooth" extensions, strakes and vortex generators, and by blowing of jets.

The close-coupled wing-canard configuration has the additional advantage of utilizing the movable canard as an aerodynamic control surface. In this case the movable canard generates (in addition to its lift and pitching moment) strong vortices that augment the strength of the wing's rolled-up vortices, resulting in an increase of the total lift at higher angles of attack. The flowfield generated at these vortices will cause an upwash on the canard due to the wing, and a downwash on the wing due to the canard that will affect the lift forces and the pitching moments on each one of these surfaces and, therefore, the total lift and the trim and control effectiveness of the wing-canard configuration. In the present investigation we will examine the capabilities of the nonlinear vortex lattice method (NLVLM) to evaluate the aerodynamic characteristics of the wing-canard configuration which is dominated by the interactions between the canard and the wing vortices.

It is generally assumed that the vortex flow over the slender wing with or without the canard can be predicted with relatively good accuracy by inviscid methods of analysis. It is clear that the generation process of the free vortices, which is started by the separation of the vortical shear layer from the body and/or the wing's surface (or at the sharp leading edges), is due to viscous effects. These viscous effects may be viewed as the result of the strong interaction between the viscous flow near the surfaces with the inviscid external flow. It is then assumed that once the shear layers separate from the surfaces or leave the sharp leading edges they then roll up into the known "rolled up vortices," and from then on the resulting flow is dominated by the inviscid vortical flow characteristics.

Et encore du pitch, du pitch, et du pitch... pas seulement en plus.

Doc3 -Northrop-

The leading edge vortex formed by flow separation from a wing leading edge extension (LEX) or wing-body strake favorably interacts with the flow over a higher aspect ratio main wing surface typical of current fighter aircraft, enhances the maneuvering lift capability of the aircraft, and strongly affects the stability characteristics. The fluid mechanic phenomenon of leading edge vortex breakdown limits, however, the maneuver performance improvement that can be obtained. Vortex breakdown forward of the wing trailing edge results in a reduction in induced lift. In a sideslip condition, vortex bursting becomes asymmetric which can lead to lateral insrabilities and when the vortex burst points arc in close proximity to the vertical or horizontal tails, abrupt loss of directional or longitudinal stability is often experienced. The location of the vortex burst points over the wing panels is highly dependent upon factors such as LEX planform shape, wing leading edge sweep angle, and deflection of leading and trailing edge flaps.

The phenomenon of aerodynamic asymmetries at high angles of attack, historically associated with missile aerodynamics, has received considerable interest in recent years due to trends in fighter aircraft design which feature long, slender fuselages of high fineness ratio. The strong vortex system emanating from the forebody, which is influenced by nose fineness ratio, bluntness, and cross-sectional shape, may assume an asymmetric orientation with subsequent large yawing moments at zero sideslip. The degree of directional stability which the aircraft will exhibit can also be determined by the forebody vortex system. Furthermore, current generation, highly maneuverable aircraft with hybrid wing planforms and slender forebodies are characterized by strong interactions between the forebody and the wing/LEX vortex systems.

Bref, comme on voit en gros, les canards à la Rafale permette toujours une meilleur optimisation aéro, fournissent aussi bien les "pitching moment" que la portance nécessaire en manoeuvre, retarde les décrochages et permettent de super angle d'attaque. Qu'il arrête là, Jackonicko, avec ses théories simplissimes à deux balles comme quoi les canards à fort bras de levier sont mieux ("Simple physics !" :lol:) !!!

Instabilité :

To give a numerical value for this "installation effect" emanating from negative stability is impossible, but it is considered to be higher than the more straightforward and better known effects of higher trimmed lift coefficients, less induced (lift dependent) drag and reduced trim drag at supersonic speeds. The last mentioned effect is due to the more moderate positive stability in the supersonic region, as compared to the normal excessive "nose heaviness" of a subsonic stable aircraft.

Ici, à priori, l'histoire comme quoi ça rend plus agile n'est même pas évoquée... Désolé Jacko... Dire que c'est son principal cheval de bataille.

Canards et aile :

The aerodynamic advantages derived from the close coupled canard configuration, foremost its good vortex flow stability up to high angles of attack (AOA), that can be translated into a very high instantaneous turn rate, and which in conjunction with pivoting canards that are automatically trimmed to give optimal lift-to-drag (L/D) ratios for all cg positions, Mach and AOA, were not technically feasible for the Viggen generation of fighters. Only full span slotted flaps on the canards were present on the Viggen, for further improvement of its already excellent Short Take Off and Landing (STOL) characteristics).

One decisive feature in obtaining good, straight pitching moment characteristics from the type of plan-form was found to lie in the slightly aft sweep of the canard pivot. This was derived through an intensive wind tunnel effort that consisted of testing a formidable number of systematically differing plan-form shapes, both for the main wing and the front surfaces.

In order to successfully meet the often contradictory performance requirements stipulated by the RSAF, a good balance had to be struck between the important wing geometrical parameters, such as sweep angle, thickness, aspect ratio, twist, camber and area.

For example, a demand for high supersonic speed capability and/or low transonic buffeting levels during heavy g-loading will be eased by high wing sweep angle, but then range and manoeuvrability will be degraded accordingly. And a thin wing, good for high speed, might be a blow to rolling performance at high dynamic pressures.

The plan-form that eventually emerged was a good balance between zero-lift, wave, and induced drag and showing a maximum L/D of 9, some 25 percent and 60 percent higher than the previous Saab fighters, the Viggen and Draken respectively. Leading edge sweep angle, actually three different angles for the main wing, is higher on the canard surface to ensure stable flow, as the up-wash there can increase the local AOA substantially.

Voilà, autant d'arguments, écrits par des spécialistes pas vraiment fictifs, et qui déplaisent énormément à notre cher pote Jacko.

Bref, dommage pour ceux qui lisent pas l'anglais (faut s'y mettre !!!), chez Dassault, c'est pas des pinioufs. :lol:

Personnelement, je trouve que les théories que Fonck nous a expliqué pendant X temps, elles sont loin d'être aussi simple que beaucoup ont voulu l'entendre.

En tout cas, l'histoire du long-moment-harm à la sauce british, parce que "simple physics", je m'en fous. :P

[Fonck]

Ca TMor je l'ai digere il y a un moment. Merci quand meme. Pour ton info, cette page du topic est deja copiee et sauvee dans mon floppy. Ca ne change pas grand chose au but que se fixaient les inges de MBB quand ils ont decide de la position des canards pour le Typhoon.

[TMor]

Ca TMor je l'ai digere il y a un moment. Merci quand meme. Pour ton info, cette page du topic est deja copiee et sauvee dans mon floppy.

Ca ne change pas grand chose au but que se fixaient les inges de MBB quand ils ont decide de la position des canards pour le Typhoon.

Merci...

Bien sûr, ça ne change rien à l'idée des gas de MBB, mais ça me fait plaisir parce que ces textes valident parfaitement la solution Dassault. Pas la peine de faire toute l'histoire de Jacko pour faire un avion maneouvrant et agile...

[bluewings]

Si ca peut aider :

The flow structure of highly swept or delta canard-wing configurations is characterized by a canard downwash which modifies the wing flowfield and an interaction between the canard and wing vortex systems. The inboard wing flowfield is often dominated by the canard downwash, and the outboard is affected by the subsequent change in wing leading-edge vortex formation and the canard-wing vortex interaction

Remarquez le "highly swept or delta canard-wing configurations is characterized by a canard downwash which modifies the wing flowfield" .

C 'est la raison pour laquelle le Typhoon a ses Canards tres en avant . Ca perd du "lift" , mais ca gagne durant les "High Alpha" .

At increasing angles of attack, the lift due to these vortices is increasing as long as the rolled-up vortices remain coherent and stable

La , on arrive a un truc qui semble complique mais qui est un fait relativement simple (J 'explique dans une minute)

Maintenant :

Similar effects of enhancing the coherence of the free rolled-up vortices and delaying vortex breakdown is also achieved by various devices such as as leadingedge extensions (LEX)

Et VLAN ! la , le F18 avec ses longues LEX prend un direct dans les dents !

Plus simplement : Quand le F18 roule beaucoup (High Alpha) , son nez s 'effondre . En gros , les vortices generee par ses longues LEX "Piquent" le Lift et les Ailes n 'en n 'ont plus assez .

C 'est peut etre la raison pour laquelle certain pilotes disent qu 'il vole comme un "Pig" (cochon) , parce qu 'il a souvent le nez "par terre" .

Photo :

Le Typhoon lui , n 'a quasiment pas de LEX . Ses canards servent a donner un incroyable pitch control , mais n 'apportent pratiquement pas de lift suplementaire .

Photo :

Rafale , il a tout ce qu 'il faut , LEX et canards . Comme l 'a dit TMor : chez Dassault, c'est pas des pinioufs . 8)

Photo :

A+

[TMor]

Remarquez le "highly swept or delta canard-wing configurations is characterized by a canard downwash which modifies the wing flowfield" .

C 'est la raison pour laquelle le Typhoon a ses Canards tres en avant . Ca perd du "lift" , mais ca gagne durant les "High Alpha" .

Tiens tiens... Intéressant comme lecture. Il faut vraiment grimper en AoA pour le Typhoon afin que je visualise les "canard downwash" aller sur l'aile... Et il n'a fait que du 70°...

Qu'est-ce qu'ils y gagnent d'après toi ? Est-ce un avantage par rapport au Rafale ? :rolleyes:

Tu dis à la fin de ton message que le Rafale a les deux (canards+LEX), mais c'est quand même pas les mêmes canards que le Typhoon, et ce que j'ai donné donne des avanages à la config Rafale, non ?

[Fonck]

"Remarquez le "highly swept or delta canard-wing configurations is characterized by a canard downwash which modifies the wing flowfield" .

C 'est la raison pour laquelle le Typhoon a ses Canards tres en avant . Ca perd du "lift" , mais ca gagne durant les "High Alpha" . "

Ce depend grandement de la fleche du delta.

C'est un phenomene qui ne serait pas aussi prononce sur le Rafale encore moins avec les LEX.

Quand a raison pour laquelle le Typhoon a ses Canards tres en avant, d'apres les inges de MBB c'est pour recuperer l'authorite de controle en tangage au tres grand angles.

Ici on ne parle que des surfaces aile/canards, on oublie le FUSELAGE du Rafale et les effets de son dessin.

http://img90.imageshack.us/img90/9977/Airflow-regeneration.gif

Le Rafale c'est pas seulement ca...

http://img80.imageshack.us/img80/5928/CleanAeros.jpg

Ni seulement ca...

http://img83.imageshack.us/img83/4456/Expansiveflow.jpg

http://img76.imageshack.us/img76/4244/Compressiveflow.jpg

http://img74.imageshack.us/img74/3441/Intake-Left-arrangement.jpg

CA ca joue grandement aussi et ca permet a l'avion un controle de profondeur plus de 30* superieur a celui du Typhoon.

[TMor]

C'est toujours marrant que t'arrives à chiffrer. :lol:

[Fonck]

TMor, je n'ai pas saisi? Chifrer c'est justement mon probleme pour valider... LOL. Passe 100* et 70* c'est a peu pres ca... >>>>> Flight HomeSubscribeYou are in: Home › News Article DATE:02/09/96 SOURCE:Flight Daily News Yves sings the praises of Rafale French military aviation's sole presence in the flying display is the naval version of the Dassault Rafale, flown by chief test pilot Yves Kerherve. He made the first flight of the carrier-capable Rafale in December 1991 and is still in love with the aircraft. "It is a wonderful experience to present the Rafale in the air," he says. An experienced naval aviator, Kerherve flew Etendard aircraft before graduating from the French test pilots school in 1977. Trials He has been involved in carrier trials of both the Dassault Super Etendard and Rafale aircraft. Carrier trials of the Rafale have now been completed, he says. "Unfortunately they are over - they were a lot of fun". Comparing the Rafale with its predecessor, Kerherve says: "In terms of handling and power the Super Etendard is very far from the Rafale. "The angle of attack on approach in the Super Etendard is 14.5o but you get severe problems at 15.5° , the margin is very narrow. "In Rafale the angle of attack is 16° but it can fly easily at 30° . Deck landings in the past were very stressful for the pilot. Now [in the Rafale] they are easy." The naval Rafale is due to go into production in 1998 and enter squadron service two years later. http://www.flightglobal.com/Articles/1996/09/02/2445/Yves+sings+the+praises+of+Rafale.html >>>>>Archives...

[TMor]

Ok, alors doit-on comprendre que la limite FCS du Rafale est de 30° ? Celle du Typhoon, c'est 29°... Avantage Rafale. :lol:

[Fonck]

L'histoire aprends comment les avions sont dessines, l'ignorer c'est mecomprendre leur nature. http://www.flightglobal.com/Articles/1999/06/09/51977/Wings+ofchange.html The respective designs eventually chosen for the Rafale and Eurofighter reveal clearly their fundamental differences, even though both are based around delta wing/canards. Dassault, with its long experience in delta wing/canard design, had already demonstrated close-coupling of the canard and wing - a solution rejected by the Eurofighter team. "We believed very strongly that the all-moving canard should be close-coupled aerodynamically to the wing," says Revellin-Falcoz. "First, it meant the canard could be located further rearwards, which, particularly in the two-seat version, would give the rear pilot better visibility for the air-to-ground mission. Second, we wanted to take advantage of the flow induction effect to the delta wing. This gave us more efficiency and better control at low speeds and high angle of attack, which was particularly important for carrier operations." The design of the intakes was another area where the two sides disagreed. "In our book, a twin-engined configuration means it must be a true twin. In other words, we never want a single engine failure affecting the other engine," says Revellin-Falcoz. This meant that separate intakes were needed, to preserve entry conditions for each powerplant under all conditions. "We think it is risky to have a chin intake, even though today's engines are so reliable," he adds. The Rafale intakes are 'semi-submerged', which are also "better for reducing the frontal signature." The landing gear, because of the Rafale's carrier role, would also be different. Catapult-assisted take-offs required a particularly strong mounting, which meant the nosegear had to be attached directly to the fuselage to transmit the loads directly through to the main aircraft structure. "That would not have worked well on a chin intake - the resulting structure would have been extremely complicated," says Revellin-Falcoz. A major contribution to the Rafale's design came from the work carried out in the mid-1970s on the ACF(Avion de Combat Future) programme. In its earlier stages, the ACF had been a relatively large, twin-engined aircraft, which proved too expensive to develop and was cancelled as the first prototype neared completion. The ACF was therefore downsized and given a single engine - becoming the Mirage 2000, which became (in different versions) the principal air-to-air and air-to-ground fighter for the French air force and, including exports, has clocked up around 600 sales. Revellin-Falcon points to Dassault's private venture effort on a twin-engined version of the Mirage 2000. The Mirage 4000 incorporated several features which became central to the Rafale's capabilities, including the close-coupled canard, advanced boron composite and graphite epoxy materials and reduced natural stability. The aircraft flew for the first time in 1979, a year after its single-engined stablemate and at the same point that the international ECA programme took shape. "So when we joined the ECA we already had a background knowledge of flight testing these two delta configurations. That gave us a natural lead-in to the Rafale", says Revellin-Falcoz.

[bluewings]

Je pense que nous avons tous vus Air Show Displays de Rafale et Typhoon . Un truc frappant , c 'est la passe en "slow speed" . Le jour ou vous verrez Typhoon voler a 110-120knots tout en conservant plein control du pitch et du roll , faites moi signe ... :rolleyes: A+

[TMor]

Ouai, c'est cool, mais moi, je préfère celui qui tirera le plus de G le moins vite... Na !

[Fonck]

Essaies bungee jumping.

[TMor]

Pffff :lol: :lol: Faudra que j'essaie, c'est sûr. Mais bon. :lol:

[TMor]

“Once the limit is removed, we will be able to pull 9g and the onset will be well over 10g per second,” he explains. “We expect the new FCS to boost performance considerably.” C'est bien ce qu'il me semblait, les logiciel des FCS actuellement en place sur le Typhoon ne sont pas les définitifs. Il recevra les derniers vers Avril 2007. Autrement dit, on a encore rien vu des capacités de manoeuvre du Typhoon (j'ai pas dit pour autant qu'il allait être meilleurs que le Rafale). Ca vient d'un article par ailleurs très intéressant... http://www.flug-revue.rotor.com/FRheft/FRHeft05/FRH0512/FR0512d.htm Une photo comme j'attends toujours d'en voir une pour le Rafale : http://www.flug-revue.rotor.com/FRheft/FRHeft05/FRH0505/FR0505d.htm

[Fonck]

J'ai pas encore tout lu mais ca a l'air d'etre plutot moyen comme amelioration. 10 G/sec. En combien de temps le Rafale peut-il atteidre sa limite "hard" de 11Gs? J'aimerais bien savoir si c'est une reduction des problemes qu'ils rencontrent ou une amelioration tout court. Franchement, vu ce qu'ils en ont tire jusqu'a present je pencherais pour la premiere solution... Quand a tirer plus de 9 G en operation normale constament... http://www.flightglobal.com/Articles/2006/06/30/Navigation/190/207549/Video+Reporter+'Steve'+blacks-out+three+times+while+riding+ with+US+Navy+Blue+Angels+Boeing+FA-18.html Reconstituez le lien car il ne tiens pas dans cette fenetre...

[TMor]

Ah Fonck, on a pas compris la même chose... ;)

Once the limit is removed, we will be able to pull 9g

Donc, il faut croire que pour l'instant, 9g, ils ne peuvent même pas !

the onset will be well over 10g per second

Le gas dit "bien au dessus de 10g/s",Scorpion traine le chiffre de 15g/s depuis des années. Je sais que tu ne l'aimes pas... Il faudra que je lui demande d'où il le sort...

Pour le Rafale, selon Scorpion, ~11g/s à 12g/s, selon une autre source à moi et que je juge super douteuse, on est aussi dans les 15g/s... Mouai... J'en sais rien du tout. :rolleyes:

[DEFA550]

Pour le Rafale, selon Scorpion, ~11g/s à 12g/s, selon une autre source à moi et que je juge super douteuse, on est aussi dans les 15g/s... Mouai... J'en sais rien du tout. :rolleyes:

Le problème avec ça n'est pas l'avion, mais le pilote. Le taux de roulis est limité pour la même raison.