Iran, in early 2019, revealed a new solid-fuel ballistic missile, the Dezful, with a range of 1,000 kilometers. Iran also claimed they produce most of their missiles in underground factories that are immune to airstrikes. The Dezful is supposed to have completed tests and entered service in late 2019. The Dezful appears to be an upgrade of the earlier (2016) Zolfaghar missile, which had a range of 750 kilometers. In 2018 at least one Zolfaghar was fired from Iran against ISIL (Islamic State in Iraq and the Levant) targets in Syria. This confirmed the range was 750 kilometers. Israeli and American efforts to gain more information about the use of Zolfaghar in Syria revealed that the missile was not as accurate as claimed and further investigation found that it was not very reliable either. It is unclear how many Zolfaghars Iran has, especially since this missile is difficult to manufacture. In 2017 it was discovered that the Zolfaghar was the same size as the earlier Fateh-313, which had a range of 500 kilometers and that the body of Zolfaghar was not made of steel, like earlier models, but much lighter carbon fiber. That would account for the 40 percent increase in range claimed for this new version of an old missile.
Zolfaghar in turn appeared identical to the Fateh-313, which appeared in 2015 with a claimed range of 500 kilometers. It was initially believed that both Fateh-313 and Zolfaghar achieved their longer range by using larger and more efficient solid fuel rocket motors. Iran has been switching from liquid fueled rockets to solid fuel as quickly as they could but the technology is difficult to master. The United States began doing this in the late 1950s and many details of the problems involved in producing reliable and efficient solid fuel missiles had appeared in print over the years. But knowing the details of the exact chemical mixture and production techniques was less easily obtained. Solid fuel rocket motors are cheaper to maintain and enable a missile to be made ready in less than 30 minutes compared to several hour for liquid fueled missiles like the SCUD. It was known that Iran has put a lot of effort into developing better solid fuel rocket motors. No one was paying much attention to what they were doing with carbon fiber materials. It is no wonder that the manufacture of carbon fiber cases and solid fuel rocket motors is underground because Iran apparently has limited production capability for both items. Knock out the handful of plants manufacturing these items and missile production is halted.
Iran was also known to import much of the technology for the guidance systems. These are believed to be INS (unjammable inertial) and GPS plus claims of optical terminal guidance which is more complex still. This makes Iran eager to get sanctions lifted because raw materials and components for the lightweight cases, solid fuel rockets and guidance systems depend on imports. These items can be smuggled in, but that costs a lot more and the sanctions have sharply cut Iran's oil sales and that is the main source of foreign currency (dollars or euros) needed to pay for imported or smuggled goods.
Solid fuel rocket developments are more obvious than carbon fiber cases or guidance systems. Iran began the switch from liquid fuel motors in in 2002 with the Fateh 110. This was a copy of the 1980s era Chinese DF-11 ballistic missile (range 300 kilometers, 800 kg warhead). Subsequent versions of Fateh followed the same development pattern the Chinese DF-11/15 went through years earlier. This included the use of GPS (American or Chinese) guidance in addition to the less accurate INS as a backup. For nuclear warheads either guidance system is accurate enough. For conventional warheads GPS is essential to avoid missing the target and being wasted because of the smaller explosive power of a conventional warhead.
The Fateh 110 is an 8.86 meter (27.5 foot), 3.5 ton rocket with a half-ton warhead. The first version had a range of 200 kilometers. By 2010 there had been two improved models, with ranges of 250 and 300 kilometers plus improvements in reliability and accuracy. The Fateh 110 was developed to replace the liquid fueled SCUD ballistic missiles Iran first obtained from North Korea in the 1980s. SCUD was developed in Russia using German World War II era V-2 missile experience. North Korea continued to supply Iran with ballistic missile technology and that evolved into the two countries trading solid fuel rocket motor and guidance system technology.
Iran appears to be adopting the same ballistic missile tactics China developed for shutting down Taiwanese air defenses during the first hours of a war. This involves using a massive number of short range ballistic missiles. Since 2009 China has maintained a force of at least 1,400 ballistic missiles aimed at Taiwan. That's up from 200 in 2000, 800 in 2004 and 1,300 in 2008. Most of these are DF-11 and DF-15 models. The DF11 (also known as the M11) has a range of 300-800 kilometer depending on warhead size plus rocket motor and flight control tech. The DF15 (M9) is basically a redesigned DF-11 that is more reliable and accurate. From the Chinese coast across the Taiwan Straits to targets in Taiwan is about 200-300 kilometers across the Taiwan Straits. The distance from Iran to key targets in Saudi Arabia or other Arab oil states is about the same.
The Chinese missiles would use high explosive or cluster bomb warheads and would basically be bombs also delivered by aircraft, but those delivered by missile are much more difficult to intercept. For that reason Taiwan is investing in an anti-missile system that would negate a large number of the Chinese missiles and so are the Arab states within range of Iranian missiles. If used, perhaps 75 percent of the Iranian missiles would actually hit their target. The others would suffer failures in propulsion or guidance systems. Each missile is the equivalent of a half-ton or one ton aircraft bomb. Initially the Chinese missiles had primitive guidance systems, meaning that the warheads will usually hit up to 500 meters from the target. The Chinese equipped their missiles with several generations of GPS tech, in response to advances in Taiwanese jamming technology. Guidance systems that are more difficult to jam are always being worked on. This technology has been much sought after by Chinese spies in the United States over the last few years.
In 2011 Iran claimed to have created an anti-ship missile, called the Khalij Fars, with a range of 300 kilometers based on the Fateh 110. What all this implies is that Iran is claiming to have developed a ballistic missile that can hit moving ships at sea. China has also claimed to have developed this technology (the DF-21D). But neither country has demonstrated their anti-ship ballistic missiles actually working. The problem is that there is no evidence that Iran has developed accurate and reliable guidance systems for these missiles and none of them have been used in combat.
Israel has an active and often very effective intelligence effort to obtain details of Iranian ballistic missiles. Israel does not make public much of what it discovers in order to keep secret its sources and methods. However there have been leaks indicating that the quality control on the more advanced ballistic missiles, like Zolfaghar and Dezful, is uneven and that these missiles are difficult to build in large quantities. Iranian press releases like to indicate otherwise and that is one thing Iran often uses press releases for. It is also telling that the hundreds of Israeli airstrikes against Iranian missile shipments to Syria and Lebanon are destroying a lot of the older Fateh 110 missiles, along with upgrade kits for older, and shorter range rockets. Israel has also bombed several factories in Syria and Lebanon that Iran has built to upgrade the older rockets with guidance systems. This involves more than just fitting nose of the rocket with the guidance system, you also have to install the control flaps which the computerized guidance system manipulates to achieve the accuracy. This is not a simple or quick update and without a facility resembling one used to actually build these rockets and missiles, the upgrade does not get done.
Israel has also introduced the new Magic Wand (David’s Sling) air defense system in 2016 which can more effectively intercept these guided rockets. This is the Israeli replacement for existing American Patriot and Hawk systems. In development for over a decade, Magic Wand was designed to be an improvement over American made Patriot systems Israel already has. The Magic Wand missiles (called Stunner) have a longer range (300 kilometers) and better capabilities. The American manufacturer of Patriot is cooperating with an Israeli firm to develop and produce Magic Wand and will apparently adopt some Magic Wand features for Patriot upgrades.
Stunner and Magic Wand are meant to complement the Iron Dome anti-rocket system, which can take down rockets with a range of up to 70 kilometers. Iron Dome has a unique feature in which the radar system computes where the incoming rocket will land. If the rocket will not hit an inhabited area, it will be ignored. Otherwise, an interceptor missile will be fired. Stunner will be used against larger rockets that will be aimed (by Syria or Hezbollah) at large urban areas, and these will almost always get a Stunner fired at them. This is part of the Magic Wand system for defending Israelis from rocket attacks. Magic Wand is expected to eventually replace the 17 Hawk anti-aircraft batteries and, eventually, the six Patriot batteries. Because of the long range of the Stunner, two Magic Wand batteries can cover all of Israel.
If Israel can destroy enough of the guided rockets and ballistic missiles Iran is shipping to Syria and Lebanon, as well as ones already there, in wartime Magic Wand could handle what the airstrikes missed.