A pantograph including: - a chassis to which a marking (R) is attached, the marking (R) including a longitudinal direction (L), a vertical direction (V), and a transverse direction (T), the longitudinal direction (L) and the vertical direction (V) together defining a vertical plane, - a bow intended to be in contact with a catenary to capture a power supply current flowing through the catenary , - an articulated arm linking the bow to the chassis is designed to vertically extend in order to move the bow in the vertical plane relative to the chassis , this articulated arm comprising at least one main rod and at least one auxiliary rod , each main rod and each auxiliary rod being substantially parallel and movable relative to each other, according to their common main axis, - an aileron assembly comprising at least one aileron movable relative to the articulated arm, - means for supporting the movable aileron , these support means being movably mounted on one amongst the main rod and the auxiliary rod, called support rod , - immobilisation means , able to immobilise the support means with respect to the support rod, - orienting means , mounted on the other one amongst the main rod and the auxiliary rod, called orienting rod , these orienting means being able to move the support means relative to the support rod against the immobilisation means, these orienting means being adapted so that - over a first range of extension of the articulated arm in which the bow moves between a low position and an intermediate position, these orienting means do not act on the support means, so that a characteristic angle (α10) of the aileron, formed in the vertical plane by the movable aileron and the main axis (A216) of the support rod, is substantially constant; and - over a second range of extension of the articulated arm in which the bow moves between the intermediate position and a high position, these orienting means act on the support means, so that the characteristic angle of the aileron continuously varies. - a chassis to which a marking (R) is attached, the marking (R) including a longitudinal direction (L), a vertical direction (V), and a transverse direction (T), the longitudinal direction (L) and the vertical direction (V) together defining a vertical plane, - a bow intended to be in contact with a catenary to capture a power supply current flowing through the catenary , - an articulated arm linking the bow to the chassis is designed to vertically extend in order to move the bow in the vertical plane relative to the chassis , this articulated arm comprising at least one main rod and at least one auxiliary rod , each main rod and each auxiliary rod being substantially parallel and movable relative to each other, according to their common main axis, - an aileron assembly comprising at least one aileron movable relative to the articulated arm, - means for supporting the movable aileron , these support means being movably mounted on one amongst the main rod and the auxiliary rod, called support rod , - immobilisation means , able to immobilise the support means with respect to the support rod, - orienting means , mounted on the other one amongst the main rod and the auxiliary rod, called orienting rod , these orienting means being able to move the support means relative to the support rod against the immobilisation means, - over a first range of extension of the articulated arm in which the bow moves between a low position and an intermediate position, these orienting means do not act on the support means, so that a characteristic angle (α10) of the aileron, formed in the vertical plane by the movable aileron and the main axis (A216) of the support rod, is substantially constant; and - over a second range of extension of the articulated arm in which the bow moves between the intermediate position and a high position, these orienting means act on the support means, so that the characteristic angle of the aileron continuously varies. <EOS>