  We use 3D hydrodynamical numerical simulations and show that jittering
bipolar jets that power core-collapse supernova (CCSN) explosions channel
further accretion onto the newly born neutron star (NS) such that consecutive
bipolar jets tend to be launched in the same plane as the first two bipolar jet
episodes. In the jittering-jets model the explosion of CCSNe is powered by
jittering jets launched by an intermittent accretion disk formed by accreted
gas having a stochastic angular momentum. The first two bipolar jets episodes
eject mass mainly from the plane defined by the two bipolar axes. Accretion
then proceeds from the two opposite directions normal to that plane. Such a
flow has an angular momentum in the direction of the same plane. If the gas
forms an accretion disk, the jets will be launched in more or less the same
plane as the one defined by the jets of the first two launching episodes. The
outflow from the core of the star might have a higher mass flux in the plane
define by the jets. In giant stellar progenitors we don't expect this planar
morphology to survive as the massive hydrogen envelope will tend to make the
explosion more spherical. In SNe types Ib and Ic, where there is no massive
envelope, the planar morphology might have an imprint on the supernova remnant.
We speculate that planar jittering-jets are behind the morphology of the
Cassiopeia A supernova remnant.
