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August 8, 2006: All future MLRS rockets will be "smart" (GPS guided), and older, unguided rockets, will be upgraded to "smart" status.
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There have been no reliability problems with the GMLRS, which has a range of 70 kilometers and, because of the GPS guidance, it has the same accuracy at any range. Unguided rockets become less accurate the farther they go.
What makes the GMLRS most useful is not just its accuracy, which is about the same as air force JDAM GPS guided smart bombs, but because the 200 pound GMLRS warhead produces a smaller bang than the smallest JDAM (500 pounds). When it comes to urban fighting, smaller is better. Less collateral damage, and your troops can be closer to the target when the explosion occurs.
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In order to get more GMLRS, all new MLRS production is being switched to GMLRS, and a retrofit kit, that will turn unguided MLRS rockets into GMLRS, has been introduced. The army believes that GMLRS will remain the most useful smart weapon, even with the introduction, later this year, of the hundred pound 155mm GPS guided Excalibur artillery shell, and the U.S. Air Force's 250 pound JDAM (the SDB, or small diameter bomb).