In 2017 Poland decided to adopt the American GMLRS (GPS guided MLRS) rocket system. Poland wanted to get GMLRS into action quickly and at the lowest possible cost. Now there is a change in plan and Poland is ordering the American made HIMARS (High Mobility Artillery Rocket System) vehicles rather than building its own version of the American HIMARS rocket launchers. For several years Polish defense studies had shown that the state-owned Polish defense industries could accomplish this. The Americans were willing to allow for license built systems, which is quite common when it comes to fellow NATO members. But in early 2018 American and Polish technical experts got together to work out the details and it was discovered that the Polish manufacturers expected to handle adapting the American tech to existing Polish truck-mounted rocket launcher systems would require more time and higher costs than earlier believed. Some of the American tech to be transferred was going to require the construction of new manufacturing facilities and that use of these facilities beyond the HIMARS contract were not guaranteed. The delays alarmed Polish military planners who increasingly saw the precision firepower provided by GMLRS, a combat proven system, becoming more urgent as the Russian threat seemed to grow. A quick recalculation determined that it would now cost about the same, even be a little cheaper to order the HIMARS vehicles rather than integrating HIMARS technology into the existing, and similar Polish Homar (“Lobster”) rocket system.
The Homar plan looked good on paper as it involved HIMARS launchers mounted on Polish 6x6 truck rather than the standard HIMARS system mounted on the 6x6 U.S. Army vehicle system that nearby Romania and other export customers purchase. The Homar plan involved buying 25 GMLRS rockets as well as 61 ATACMS rockets, 34 practice rockets 1,642 GMLRS guidance systems to be fitted to Polish made rockets as well as GMLRS guidance system test and maintenance systems. This $250 million sale was to enable Poland to build a Polish version of HIMARS launchers under license and integrate the Polish HIMARS with Polish artillery fire control systems using NATO standards.
Most export customers find that the American made $5 million HIMARS truck mounted MLRS (Multiple Launch Rocket System) is already a bargain. That’s what the U.S. Army and Marines found when they adopted HIMARS, which carries only one, six MLRS rocket pod instead of two in the original larger, tracked, MLRS vehicle. Initially, a major attraction was that the 12-ton truck could fit into a C-130 transport (unlike the 22 ton tracked MLRS) and was much cheaper to operate. The first HIMARS entered service in 2005, about a year after GMLRS (GPS guided MLRS rockets) did. The two new innovations worked well together and were a major reason for the success of the GMLRS and the HIMARS rocket launcher. The U.S. no longer buys the tracked MLRS or unguided MLRS rockets.
Poland, like most HIMARS and MLRS users, are now only buying guided rockets. Poland had originally planned to integrate longer range (150-499 kilometer) Homar guided rockets it was already developing into the American HIMARS system. Poland was a major weapons manufacturer during the Cold War when it was occupied by Russian military forces and secret police. During that period Poland produced Russian weapons under license and gradually developed improved versions of the Russian designs. It turned out that the tech the HIMARS used was pretty powerful, enabling HIMARS to operate (move, receive a target order and launch the GMLRS) using as few as one of the normal three man crew. All that tech is great and Poland would still like to build it under license but the army needed the HIMARS capability now, not later.
Since joining NATO in 1999 Poland has largely replaced Russian weapons with Western ones or upgraded Russian systems to NATO standards. That alone created a new business opportunity for Polish defense firms and Poland is again becoming a major arms producer. Thus it was no surprise that Poland wanted to build its own version of the guided MLRS rockets, a weapon that had been in service since 2004. This was the GMLRS (guided multiple launch rocket system). Like the unguided version, the GMLRS is packaged and used in containers (pods) holding six rockets each. The fire control system was upgraded to handle precision targeting rather than just a general area. Poland already builds several truck-mounted rocket systems but these still use unguided rockets. Moving up to HIMARS type launch vehicles and GMLRS type rockets was seen as the future and it still is. Getting there just turned out to take longer than the Polish Army thought necessary.
Since 2004 over 3,000 GMLRS rockets have been fired in combat. GMLRS rockets cost about $100,000 each and have been very successful. That has meant even less work for tube artillery, which had dominated the battlefield since the 17th century. The Polish GMLRS rockets will be based on existing Polish rockets and eventually be cheaper to manufacture. Meanwhile, the U.S. manufacturer has had to resume production of the M142 American HIMARS vehicle system for the growing number of export customers.
The 309 kg (680 pound) GMLRS missile is a GPS guided 227mm rocket. It was designed to have a range of 70 kilometers and the ability to land within meters of its intended target, at any range. This is possible because it uses GPS (plus a backup inertial guidance system) to find the target location it was programmed with. In 2008 the army tested GMLRS at max range (about 85 kilometers) and found that it worked fine and this is the design Poland will use. This enables one MLRS/HIMARS vehicle to provide support over a frontage of 170 kilometers, or, in places with wide open spaces, like the Eurasian Plains Poland shares with Russia, HIMARS can provide precision fire support over an area of about 20,000 square kilometers. This is a huge footprint for a single weapon (an individual MLRS/HIMARS vehicle), and fundamentally changes the way you deploy artillery in combat. By way of comparison, Excalibur (GPS guided 155mm shell) has a max range of 37 kilometers, and 120mm GPS guided mortars about 7.5 kilometers.
Until recently most of the GMLRS rockets were fitted with an 89 kg (196 pound) M31A1 high explosive ("unitary") warhead. About half of that is actual explosives. That's twice as much explosive as the U.S. Air Force 130 kg (285 pound) SDB (Small Diameter Bomb). A 155mm artillery shell has 6.6 kg of explosives, and the 500 pound (227 kg) bomb has 127 kg of explosives, which produced an excessive blast for many urban combat situations. The GMLRS seemed to be just right most of the time. In 2014 an M30A1 warhead was introduced in 2016 and it used less explosive but added 180,000 tungsten pellets which were effective against personnel and unarmored vehicles over a much larger area. The GPS guided ATACMS rocket has a range of 300 kilometers and a 230 kg (500 pound) warhead.
GMLRS has been used with great success in Iraq and Afghanistan, where most have been fired so far. The guided rocket is much more effective than the older, unguided, version, and has replaced it for most users. No more of the unguided rockets are being purchased by the U.S. The accuracy of GMLRS means that one rocket does the job that previously required a dozen or more of the unguided ones. That's why HIMARS is so popular. While HIMARS only carries six rockets, that's often enough to last for days in places like Afghanistan, even when there's a lot of combat.
Because of precision weapons like GMLRS and smart bombs, since the end of the Cold War in 1991, the U.S. Army has drastically reorganized and reduced its artillery force. At the end of the Cold War most artillery was conventional “tube” artillery. That meant towed 105mm, 155mm, 203mm howitzers and self-propelled 155mm howitzers. The MLRS, a 12 tube 227mm unguided rockets was just entering service when the Cold War ended. In the 1990s it became obvious that smart bombs (JDAM) first used in the 1991 Gulf War, were more effective than artillery and that led to a major shift away from using artillery. By 2004 over 40 tube artillery battalions had been disbanded.
Noting the success of GMLRS, Russia and China have developed and put into service their own GPS guided rockets. Russia has long led in the design of new rocket systems was is playing catchup when it comes to using guided rockets. The multiple rocket launcher was first developed by the Russians before World War II as a cheap alternative to massed artillery fire by individual guns. Long seen as a supplement to regular artillery, the introduction of the high tech U.S. MLRS rocket system in the 1980s began to make a lot of conventional artillery obsolete even before GMLRS came along. Of course, artillery has always been ripe for innovation. The U.S. 175mm gun, introduced in the 1960s, was rendered obsolete in the 1980s with the introduction of special long range ammo for the 203mm (8 inch) howitzer. The U.S. Army stopped using the 175mm gun in the 1970s. When the MLRS entered service, one of the three batteries in each division's 203mm howitzer battalion was equipped with MLRS units instead. But MLRS proved so effective that the 203mm howitzer battalion became an MLRS battalion and the 203mm gun was dropped by the U.S. Army.
There were always non-divisional MLRS battalions, as the MLRS was seen, from the beginning, as an ideal weapon for massed artillery fire. The Gulf War allowed the MLRS to show off what a potent weapon it could be. The larger rockets also provided room for more complex payloads (cluster and "smart" munitions) and guidance systems. This was another example of how technology can transform an old weapon. While the Russians have been using rocket launchers for over 70 years, they never got around to enhancing their effectiveness with a lot of technology until recently and then only because they noted others were doing so and succeeding. Now everyone is changing their artillery forces and adapting to the use of many fewer guided projectiles.