ARE THE ROTATIONAL AXES PERPENDICULAR TO THE ORBITAL PLANES IN THE BINARY-SYSTEMS .1. ASYNCHRONOUS LONG-PERIOD RS CVN STARS

We show that only 12 out of 27 analyzed binaries have data good enough for reliable determination of i(orb) and i(rot). In 4 systems (out of these 12) assumption about coplanarity of rotational equatorial plane and orbital plane is justified. In the remaining cases rotational axes are not perpendicular to the orbital planes (non-coplanar case). The commonly accepted assumption about the coplanarity of rotational and orbital planes should be revised.