Over the past few years the Israeli army has been changing its approach to artillery. This began in 2011 when Israel decided to replace most of its 155mm artillery with GPS guided rockets. Now it is training some of these rocket battalions to fire GPS rockets into inhabited areas. For the present this means Gaza, where Israel has heretofore used F-16s firing smart bombs or helicopters using guided missiles to attack terrorist targets there. Now, the GPS guided rockets will take over some of these missions. This will be a lot cheaper and, with more shoulder fired anti-aircraft missiles showing up in Gaza, a lot safer for Israeli aircraft.
These changes began after Israel noted the success the Americans were having with GPS guided rockets in Afghanistan. The weapon used was the 309 kg (680 pound) GMLRS (guided multiple launch rocket system), a 227mm GPS guided rocket that was first used in 2004. It has a range of 70 kilometers and the ability to land within meters of its intended target at any range. This is because of using GPS, plus a less accurate back up inertial guidance system, to find its target. Israel accepted that the American use of GPS guidance in rockets, while more expensive, was more effective than the cheaper (but less accurate) Israeli developed rocket guidance system and even cheaper unguided artillery shells.
Israel has gone ahead and developed its own GPS guided rockets, like the Romach, a 175mm rocket similar to the American GMLRS but smaller and with a range of 35 kilometers. Israel has also developed a GPS guided 155mm artillery shell and 120mm mortar shell. Each tank battalion has some of these 120mm mortars and using GPS guided shells does not require using a lot of ammo to get the job done. In effect, Israel has all but eliminated the use of the traditional artillery barrage, reducing ammo use by over 90 percent. This meant many artillery units were disbanded.
This radical shift in artillery weapons has been coming since the 2006 war with Hezbollah, when the Israelis found that they did little damage to Hezbollah bunkers, even though over 120,000 unguided 155mm shells were fired at them. Meanwhile, they noted that the U.S. 227mm MLRS rockets with GPS guidance was excellent at taking out similar targets in Iraq and Afghanistan. So Israel equipped its 160mm Accular rockets with GPS. These 110 kg (242 pound) rockets have a range of 40 kilometers and enable one bunker to be destroyed with one rocket. The larger and more accurate (lands within 5 meters of the target versus 10 meters) Romach came out of that project.
Israel always recognized the superiority of GPS in some situations. For example, Israel developed LORA (Long Range Artillery Rocket) which is similar to the U.S. ATACMS. Each LORA missile weighs 1.23 tons and carries a half ton warhead. With a range of 300 kilometers, GPS guidance is used to land the warhead within 10 meters (31 feet) of the aim point. These missiles are expensive. The similar U.S. ATACMS, which is fired from a MLRS container that normally carries six of the standard MLRS rockets, cost a million dollars each. It's often a lot cheaper if you can use smart bombs (which cost less than $50,000). But if you don't have aircraft up there, or control of the air is contested, you can get a LORA missile on a target within ten minutes of the order being given.
The United States has shared its experience with GPS guided rockets in Iraq and Afghanistan, providing data on how these weapons actually perform in built-up areas. This made it clear that GPS guided rockets were the way to go for targets in Gaza. Israel expects to replace a lot of artillery shells, air delivered missiles, and bombs with its GPS guided rockets and take out more targets with far fewer rockets and artillery shells.