  According to a Barrow's solution for the scale factor of the universe, the
main properties of the tachyon inflation model in the framework of RSII
braneworld are studied. Within this framework the basic slow-roll parameters
are calculated analytically. We compare this inflationary scenario against the
latest observational data. The predicted spectral index and the
tensor-to-scalar fluctuation ratio are in excellent agreement with those of
{\it Planck 2015}. The current predictions are consistent with those of viable
inflationary models.
