Position-velocity diagrams confirming the presence of two velocity components in W43 (see Sect. 3.1) and revealing the H i/¹²CO 1–0 cloud ensemble #1 (white arrow, see Sect. 3.3). The distributions of H i (color) and ¹²CO 1–0 (contours) are plotted against Galactic latitude, kept as the y axis, as in Fig. 2. The H i and ¹²CO 1–0 lines have been summed in a) over the l = 29°−32° longitude range corresponding to W43 and its H i envelope and in b) over the l = 27°−29° longitude range covering part of the H i/¹²CO cloud ensembles presented in Sect. 3.3. The contours run from 400 to 2000 K with a step of 400 K. The white boxes represent the latitude extent and velocity range of the W43 molecular complex (continuous lines) and its H i envelope (dashed lines).