Retrieved shape and kinematics of the wind outermost emitting layer in the red lobe. Radius r (top left), velocities υ_ϕ (top right) and υ_ɀ (bottom right), and specific angular momentum r × υ_ϕ (bottom left) are shown as a function of deprojected altitude ɀ. The data points with error bars represent values for CH₃OH (pink) and H¹³CN (black), derived from the P–V measurements in Table A.1 and deprojected by an inclination i = 30°. The values of r × υ_ϕ are computed using the average flow radius between the two edges. The green lines show our simple conical model that best fit the P–V diagrams in Fig. 5, assuming a flow along the cone walls.