A wave solution of the Einstein equation is found. It can be regarded as gravitational field of a pointlike source moving with acceleration. This solution is valid only far enough from the source. To analyze energy and momentum flows carried by gravitational wave described by this solution, the canonical energy-momentum tensor introduced previously (Drivotin O.I. Mathemaical Basics of the Field Theory. St.Petersburg, St.Petersburg Publ. Co., 2010) is used. Densities of energy, energy flow and momentum flow are found. The computations show that the momentum transferred from the particle to the gravitational field go away with the wave.