Existing American cruise missiles slated for replacement are still being upgraded. Three years ago, the American military placed a multi-year contract for 10,000 GMLRS guided rockets per year through 2026, at a cost of $170,000 each. An unspecified number will be the longer-range SDB version, which uses an SDB glide bomb as a second stage and extends range to 150 kilometers, compared with 70 kilometers for the standard rocket. The SDB uses multiple guidance systems to strike targets, including moving ones, with greater precision. Some SDB versions have been used effectively in Ukraine. Because of growing export orders, plans call for increasing total GMLRS production to 14,000 rockets per year. Ukraine is currently the largest GMLRS user, having received about 3,000 rockets and at least 20 HIMARS launcher vehicles in the past year, making it the largest combat user. U.S. forces previously used GMLRS in Iraq and Afghanistan. GMLRS entered service in 2004, followed by the smaller, truck-mounted HIMARS launcher in 2005. Together, GMLRS and HIMARS have proved popular with a growing number of export customers. GMLR-ER, the longer-range, 150-kilometer version of GMLRS, recently entered service.
Raytheon, the American manufacturer of Tomahawk cruise missiles, has received orders from Japan and Australia for a total of 600 of the new Mark V (5) version of the Tomahawk. Both countries will install the missiles on their warships to provide a long-range guided missile capable of hitting moving targets over 1,000 kilometers away. The Tomahawk has undergone several improvements over the last decade and is now one of the most effective land-attack and anti-ship weapons available to American and allied warships.
In 2020, the U.S. Navy introduced Tomahawk Block 5, the first new version since Block 4 in 2005. The block versions represent a series of individual upgrades that have turned the current Tomahawk into a substantially different cruise missile than the previous block. Block 5's unique new features include the ability to hit ship-sized targets at maximum range (over 1,600 kilometers) using a new target seeker. Block 5 also uses a new warhead with greater penetrating power against large warships and greater effectiveness against all targets. It also has upgraded communication and navigation systems that are more resistant to jamming and other EW (Electronic Warfare) measures. This means Block 5 communications are harder to detect and disrupt. The navigation system can function even with heavy GPS jamming thanks to a more accurate, unjammable INS (Inertial Navigation System). Another notable feature is that Block 5 does not increase the price, which remains between $1 million and $1.5 million per missile, depending on the features. That’s much cheaper than high-speed missiles, which cost three or four times more, are heavier, and have shorter range. The relatively low cost of the Tomahawk makes it effective for more missions, like attacking land targets or being used in large numbers. All Block 4 Tomahawks are being upgraded to Block 5, and the remaining Block 3s will be retired because most were built in the 1990s and are no longer worth the expense of upgrading and refurbishing.
Most Tomahawks in U.S. service are carried and fired from surface ships or nuclear submarines (SSNs) in VLS (Vertical Launch System) cells. There is also a torpedo-launched version, which all British SSNs use. The Tomahawk has quietly become the U.S. fleet's primary offensive weapon.
The RGM-109 Tomahawk Land Attack Missile weighs 1.2 tons, is six meters long, and has a range of 1,600 kilometers. It reaches its target at 600-900 kilometers per hour, flying at an altitude of 17-32 meters, and is propelled by a jet engine generating only 273 kg of thrust. Accuracy is on a par with JDAM (10 meters). The Tomahawk can be reprogrammed in flight to hit another target and carries a digital video camera, allowing someone to check prospective targets.
With Block 4 came the new JMEW (Joint Multi-Effects Warhead System) warhead. This 450 kg warhead is designed mainly to penetrate underground bunkers, but it also delivers excellent blast effects against less robust targets. Exact penetration was not revealed. JMEW uses laser terminal guidance, enabling it to hit within a few meters of its aiming point. JMEW can also hit moving targets, like ships.
When the Tomahawk appeared in 1983, it was one of the first combat UAVs (unmanned aerial vehicles), but it wasn't reusable. The Tomahawk has been a primary land-attack weapon for surface ships and submarines since the 1990s. The Navy has manufactured over 6,000 so far. The U.S. Navy has fired over 2,200 in combat and over 600 for training and testing. The U.S. Navy currently has over 3,000 Tomahawks on its warships or in storage. Tomahawk is expected to remain in service until 2040, with older ones refurbished to extend their useful lives. That usually means replacing or upgrading batteries and electronics, along with older mechanical components.
Block 0, 1, and 2 Tomahawks were introduced during the Cold War, which ended in 1991. Some Cold War versions of Tomahawk were optimized for ranges of up to 2,500 kilometers, or for use from aircraft carrying nuclear warheads. These were gone by the time Block 3 entered service in 1994. In between new blocks, there were often major upgrades. Block 4 received a major upgrade in 2012 with the addition of GPS and in-flight remote control. The more recent upgrades improved the guidance system and defensive capabilities against electronic jamming. The Navy recognized the need for these new features in 2015, when it tested the current Block 4 Tomahawk to determine whether its new two-way communications capability could enable it to hit moving targets effectively. The Block 4 did so, but not under combat conditions. That is, not with warships using defensive or electronic weapons to shoot down the incoming missile or mislead its guidance system. One navy test used a nearby aircraft, possibly a drone, to track the target ship's exact location. A satellite could also do that. A fully developed anti-ship capability for the Tomahawk requires regular guidance-system upgrades to let it operate without constant two-way communications.
The U.S. Navy knows the Tomahawk is not the ideal anti-ship missile. Against modern defenses, anti-ship missiles must travel faster than a Tomahawk and have better terminal guidance. The speed problem cannot be fixed, but the Tomahawk could be equipped with a more capable terminal guidance system. That might handle the tracking and targeting needed for guns and missiles designed to knock down anti-ship missiles as they close in. In any event, Tomahawk Block 5 has a way to go before it is a competitive anti-ship missile against modern warships. But developing and testing upgrades will give Tomahawk a useful anti-ship capability without making it the most effective anti-ship missile on the market.
There are apparently novel proposals to use a radically new anti-ship warhead that turns Tomahawk into a two-stage missile, with the warhead making the final attack at much higher speed. That increases the cost and weight of the Tomahawk, a stable, reliable design with extensive combat experience. It was easier to tinker with the guidance system, warhead, and range and develop affordable new capabilities that work. One reason Tomahawk remains useful is its ability to do more reliably and affordably. Many new cruise missile designs can do high-speed attack, but at great expense. Tomahawk can carry out a wide range of missions, many of which do not require high speed or a more elaborate terminal guidance system.
Because of these constant improvements and consistent reliability, American (and other) warships continue to use Tomahawks in combat regularly. Targets tend to be land-based and not mobile. Most of these uses are publicized, but some are not. Several hundred Tomahawks were used in massed attacks against Libya in 2011, which demonstrated the effectiveness of Tomahawks in delivering major airstrikes on short notice, anywhere in the world, without losing more expensive manned aircraft and exposing their pilots to getting shot down and captured. Tomahawk is also an ideal weapon for a potential war in the Pacific against China. This would be a war with long distances between targets, and Tomahawk can handle that, along with many other tasks. The fleet goes to sea with lots of Tomahawks, and quantity matters as much as reliability and a track record of success.
The planned Tomahawk replacement is currently the NGLAW (Next Generation Land Attack Weapon). Development of a Tomahawk successor has been underway since the 1990s, and the current (NGLAW) effort is for a cruise missile that will be heavier (2.2 tons), have a longer range (2,000 kilometers), and carry a larger (1-ton) warhead than the Tomahawk. NGLAW will be stealthier and use a combination of new guidance and targeting systems to improve the chances of success. Price will probably be the key factor, but it is expected to cost at least twice as much as the Tomahawk. NGLAW has been going on for so long because it’s not easy to develop a Tomahawk replacement that justifies the higher weight and cost of a new missile, especially when so many navies are satisfied with updated Tomahawks.