  Spiral galaxies that move through the intracluster medium lose a substantial
amount of their gas discs due to ram pressure stripping. The recent
observations of NGC 4388 by Oosterloo & van Gorkom 2005 reveal a tail of
stripped gas of ~ 100 kpc behind the source galaxy. We present first 3D
hydrodynamical simulations of the evolution of such ram pressure stripped
tails.
  We find that if the ICM wind does not vary significantly over a period of a
few 100 Myr, subsonic galaxies produce a tail with regular features similar to
a von-Karman vortex street. In this case, the tail widens systematically by
about 45 kpc per 100 kpc distance behind the source galaxy. The widening rate
is independent of the galaxy's inclination for a large range of inclinations.
For supersonic galaxies, the tail is more irregular than for subsonic ones.
  The tail observed for NGC 4388 is narrower than the tails in our simulations.
Reasons for this difference may be additional physical processes such as heat
conduction or viscosity. In addition, we conclude that the observed S-shape of
this tail is not due to von Karman oscillations, because this galaxy is likely
to move supersonically. A reason for the observed shape may be motions in the
ambient ICM.
  Finally, we discuss implications for the distribution of metals in the ICM
due to ram pressure stipping.
