A simple generalization of large-scale kinetics is used to model the linear transient response (LTR) of the magnetotail plasma parameters to changes in a mantle particle source. A change in the source intensity results not only in changes in magnetotail plasma density but also in temporary changes of the order of a few hundred kilometers per second in the local bulk flow velocities which last for 10--20 min. The effect that dominates the initial stage of the magnetotail response, particularly in the distant tail, should be the ballistic effect of fast ion beams. While LTR does not include the self-consistent responses of the magnetic and electric fields to the changes in plasma parameters, its effects may be significant for timescales of minutes. ¿ American Geophysical Union 1995