Israel has completed testing its Trajectory Correction System (TCS) for the U.S. 227mm MLRS unguided rocket system. TCS was originally developed for Israeli 160mm rockets. TCS uses rockets equipped with a guidance system and radio. The ground portion of TCS consists of a control unit that tracks the position of the rockets in flight, calculates where they will land, and sends orders to the guidance system (small vanes) in the rocket. This makes the rockets as accurate as artillery shells. TCS is cheaper than GPS guided rockets. The Israel TCS MLRS rockets also have a larger rocket motor, that gives it a range of 60 kilometers. Normally, unguided rockets are less accurate at longer ranges. But with TCS, they have the same accuracy at any range. The greater accuracy makes up for the smaller (to make room for the larger rocket and guidance system) warhead. The Israeli manufacturer, IMI, worked with the U.S. manufacturer of MLRS is adapting TCS to the MLRS. This will help in efforts to sell TCS to the United States. Israel bought 48 MLRS launchers a decade ago, but found that to use them in counter-terrorism operations, more accurate rockets were needed.