Recent NMR experiments on superfluid He-3 in an aerogel suggest that t
he superfluid phase found might be different from the A and B phases p
resent in the bulk. Theoretical calculations indicate that the polar p
hase is the leading alternative candidate. In rite present paper we de
rive the hydrodynamics of the polar phase, We study the influence of t
he magnetic dipole interaction and of a weak external magnetic field i
ncluding the k = 0 dynamics relevant for NMR, It turns out that cw NMR
experiments can be used to distinguish the polar phase from the A pha
se provided one can orient the preferred direction of the polar phase
in real space parallel and perpendicular to the container walls of an
experimental cell, We also examine the influence of the presence of th
e aerogel on the reversible and dissipative hydrodynamics generalizing
earlier work on superfluid He-4 in aerogels.