 Russia's found way to throw Hamar's rockets off course. Russia has been using jamming techniques in recent months to make the US supplied Hamar's mobile multiple rocket launchers miss their targets more frequently CNN reported citing five u.s UK and Ukrainian sources familiar with the matter these efforts are making GPS guided munitions increasingly less effective in terms of accuracy a Ukrainian drone operator was quoted as describing the efforts to disrupt the work of Hamar's launchers as significant and something he had not seen before last November a Pentagon official described the process of finding new ways to combat Russia's efforts to throw the rockets off course as a constant cat and mouse game a senior Pentagon official told CNN that the US has been helping the Ukrainians to fight the jamming by adjusting targeting software and constant tweaking to get them to stay effective the US has committed 38 Hamar systems to Ukraine since the conflict broke out according to the Pentagon and the State Department