  We investigate the disappearance of collective flow in the reaction plane in
heavy-ion collisions within a microscopic model (QMD). A systematic study of
the impact parameter dependence is performed for the system Ca+Ca. The balance
energy strongly increases with impact parameter. Momentum dependent
interactions reduce the balance energies for intermediate impact parameters
$b\approx4.5$ fm. Dynamical negative flow is not visible in the laboratory
frame but does exist in the contact frame for the heavy system Au+Au. For
semi-peripheral collisions of Ca+Ca with $b\approx6.5$ fm a new two-component
flow is discussed. Azimuthal distributions exhibit strong collectiv flow
signals, even at the balance energy.
