  The sunspot penumbra is usually observed in the photosphere and it is of
particular interest for its magneto-convection which seems to transport the
heat from the top of the convection zone into the solar atmosphere. It is well
known that the penumbra magnetic field extends in the upper layers of the solar
atmosphere forming the so called super-penumbra. Thanks to the application of
the Self Organizing Map technique to a spectral dataset containing
monochromatic images acquired along the Ca II 854.2 nm and H$\alpha$ 656.28 nm
lines, we were able to segment the penumbra and to measure the plasma velocity
along the chromospheric portions of penumbral filaments. We found that the
head, body and tail of penumbral filaments show vertical flows compatible with
the persistence of the Evershed flow. Instead, the inverse Evershed flow has
been observed only in the outer portion of the super-penumbra. We found that
two opposite Evershed regimes work next to each other, without overlapping and
both contribute to the downflow around sunspots. These results confirm the
uncombed model of the sunspot penumbra and provide some hints that the downflow
around sunspots may be ascribed to the magnetic field dragging the plasma down.
