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Paul Rousseau, a journalist working for Le Temps, wrote an article about Wilbur Wright, his flights and aeroplane that he had witnessed flying and saw on the ground close to Le Mans, France.

It is known that the Wrights used a method called "wing warping" or "gauchissement des ailes" for stabilizing their plane in roll.

I do not understand why Paul Rousseau said: "le levier, dont la manœuvre des plus simples tord à gauche les ailes et procure l’indispensable stabilité" (see the citation). In reality the stability was obtained by twisting the wings both to the left and to the right and always symmetrically, one wing to the left the other to the right or more precisely one clockwise the other anti-clockwise.

"Les aéroplanes Wright n’ont pas de queue. Entre les plans, distants de 2 m. 40, se trouve le moteur à 4 cylindres de 25 chevaux de puissance, œuvre exclusive des frères Wright. A droite du moteur, un radiateur en tubes plats en cuivre; à la gauche, les sièges du pilote et du passager et le levier, dont la manœuvre des plus simples tord à gauche les ailes et procure l’indispensable stabilité. Partout des poulies, sur lesquelles glissent ingénieusement des fils d’acier, qui déterminent les mouvements nécessaires. Le moteur transmet son énergie à deux hélices tournant en sens inverse au moyen de chaînes courant dans les tubes d’acier qui les guident. Ces hélices de 2 m. 50 de diamètre travaillent à l’arrière; elles sont en bois. Deux longs patins supportent l’ensemble à 40 centimètres du sol." (Source: 1908-08-12, Paul Rousseau, “L’aviateur des frères Wright”, Le Temps, Paris, August 12, 1908, col. 6, p. 2.)

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Firstly, according to the dictionary, there is no relation btween "gauchissement" and the word "gauche" as meaning "sense", as opposed to "droite" (right).

Secondly, from this historical account can be gathered that the lever was not a control on the big wings but on the elevator (small wings in front); the warp on the big wings (not right or left but up and down) was by means of a hip cradle in which the pilot was lying and that could be moved lateraly on the inferior plane; the cables hooked from the cradle to the extremeties caused the warping.

Un jour, Wilbur, en tordant machinalement une boîte en carton, eut une idée de la solution au problème. A partir de là, les deux frères conçurent un mécanisme permettant à la voilure de se « tordre ». Une extrémité de l’aile montait tandis que l’autre descendait, le tout permettant une maîtrise latérale de l’engin.

La clé pour résoudre le problème qui a conduit à l’écrasement du 23 septembre repose dans la queue verticale. Le 4 octobre, les frères Wright construisirent un nouveau gouvernail, vertical, actionnable, et lié au mécanisme de torsion de voilure. Cela permit au pilote de diriger le planeur vers l’aile inférieure pour compenser l’augmentation de la résistance de l’aile supérieure lors du virage. Avec cette modification du système de pilotage, leur exploit fut rendu possible et leur invention fut achevée.

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https://fr.wikipedia.org/wiki/Wright_Flyer Le Flyer est un biplan à configuration canard, la gouverne de profondeur étant le plan avant. Le pilote est allongé sur le ventre au niveau de l'aile inférieure. Il contrôle l'inclinaison et la direction en se déplaçant latéralement dans un berceau fixé à ses hanches. Le cadre tire sur des câbles qui gauchissent (déforment) les ailes en sens contraire et font en même temps tourner la gouverne de direction (c'est ce que l'on appelle une conjugaison roulis - lacet).

You can see from what follows that the lever (elevator control) was used to control the pitch wings (elevator) and that it was on the left;

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It appears therefore that "le levier, dont la manœuvre des plus simples tord à gauche les ailes et procure l’indispensable stabilité" refers not to the main wings but to the small ones and that "à gauche" is nothing more than a reference to the place of the lever looking from the back of the plane towards the front.

enter image description here "Tord les ailes" is probably not the best term but as those wings are not used by merely given them an inclination but by changing their shape as they have flexible ribs, it is not fundamentally wrong.

Correction specific to the model of Flyer used in France in August 1908; a passenger could now take place in the plane and a sitting position was now possible for bothe pilot and passenger; moreover the system of warping of the main wings was controled by means of a lever on the right as the hip cradle was not used for that any more. The system of stabilisation by means of the elevator remained unchanged. There is much information to be gleaned from the following link: http://claudel.dopp.free.fr/Les_planeurs/Technique/Gouvernes_commandes/Gouvernes_commandes.htm

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    The August 1908 Wright plane, that Paul Rousseau saw, did not use a cradle. – simplex Jan 2 at 18:58
  • @simplex This is right; I found new evidence: claudel.dopp.free.fr/Les_planeurs/Technique/Gouvernes_commandes/… The text about the 3rd occurrence of "berceau" shows that the cradle had just been removed in the A model that flew in France. However the system for the elevator remained unchanged and its lever was still on the left. – LPH Jan 2 at 19:38
  • The front rudder only controlled the pitch. The roll was controlled by twisting the main wings and also by moving the vertical rear rudder to fight against adverse yaw. I have understood that there existed a lever somewhere to the left (à la gauche, les sièges du pilote et du passager et le levier) but why would have this left lever twisted the wings only to the left? – simplex Jan 2 at 19:53
  • @simplex I don't think this is what was meant; there were actually 3 levers and the central one was used for the main wings while the left and right were a single command for only the pitch, so that pulling either on the left one or on the right one had the same effect. There is no doubt, though, that this could have been put more clearly by the journalist. – LPH Jan 2 at 20:07

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