(a) Example of two spacecraft cuts at a Clock Angle (CA) of 90° and 270° when viewed from the N direction. The ellipse represents the ring of possible velocities of the spacecraft from Fig. 3. In this example, the switchback structure (red cylinder) is centred on the ring of velocities, so both spacecraft cuts are at the same angle, and therefore only one value of D is measured. (b) In this example, the alignment direction of the switchbacks has been rotated by ϕ_A in the RT plane. This means that the spacecraft measures different values of D depending on the CA.