  We present a study, based on Gaia DR2, of the population of blue straggler
stars (BSS) in the open clusters Trumpler 5, Trumpler 20, and NGC 2477. All
candidates were selected according to their position in the color-magnitude
diagram, to their proper motion components, and to their parallax. We also
looked for yellow stragglers, i.e., possible evolved blue stragglers. We found
that Trumpler 5 hosts a large BSS population, which allowed us to analyze their
radial distribution as a probe of the cluster's dynamical status. The BSS
distribution was compared with that of red giant branch stars (RGB) to evaluate
mass segregation. Our results indicate that blue straggler stars are not more
centrally concentrated than RGB stars in any of the clusters. The radial
distribution of BSS in Trumpler 5 is flat. Additionally, using a multi-epoch
radial velocity survey conducted with the high-resolution spectrograph
FLAMES/GIRAFFE at VLT, we measured the radial velocities of a sample of
stragglers, for the sake of comparison with the mean radial velocity and the
velocity dispersion of the clusters. Based on the radial velocity variations
for different epochs, we roughly classified these stars as possible close-or
long-period binaries.
