  We present a method to find the stationary solutions for fast flavor
oscillations of a homogeneous dense neutrino gas. These solutions correspond to
collective rotation of all neutrino polarization vectors around a fixed axis in
the flavor space on average, and are conveniently studied in the co-rotating
frame. We show that these solutions can account for the numerical results of
explicit evolution calculations, and that even with the simplest assumption of
adiabatic evolution, they can provide the average survival probabilities to
good approximation. We also discuss improvement of these solutions and their
use as estimates of the effects of fast oscillations in astrophysical
environments.
