  We study the sensitivity of displaced vertex searches for heavy neutrinos
produced in W boson decays in the LHC detectors ATLAS, CMS and LHCb. We also
propose a new search that uses the muon chambers to detect muons from heavy
neutrino decays outside the tracker. The sensitivity estimates are based on
benchmark models in which the heavy neutrinos mix exclusively with one of the
three Standard Model generations. In the most sensitive mass regime the
displaced vertex searches can improve existing constraints on the mixing with
the first two Standard Model generations by more than four orders of magnitude
and by three orders of magnitude for the mixing with the third generation.
