In July 2017 Iran announced it had begun mass production of its Sayyad 3 anti-aircraft missile which, when used with the Bavar-373 radar and fire control system, can intercept aerial targets up to 150 kilometers distant. Each Bavar-373 system can simultaneously track 30 aircraft and direct Sayyad 3 missiles at twelve of those targets.
Iran insisted that it had developed its own clone (Bavar-373) of the Russian S-300 anti-aircraft missile system. Iran began work on the Bavar-373 in 2010, after Russia refused to deliver S-300 systems Iran had ordered. International sanctions, plus pressure from the United States and Israel led Russia to cancel the Iranian order. Iran has issued progress reports ever since and Bavar-373 was supposed to be ready for final testing in 2014, then 2015, then 2016 when some tests apparently took place. The final testing is supposed to take place before the end of 2017. The Israelis indicate they are not concerned about the Bavar-373 and that they can handle it. Russian and Western air defense experts doubt that the Iranians have managed to create anything close to the capabilities of the S-300 systems Russia has already delivered once the sanctions were lifted in mid-2015.
The Iranian designed and built Sayyad 3 missile for the Bavar-373 appears to be the same size and shape as the S-300 missile and carried in similar canisters. Iran insists that Bavar-373 is superior to the S-300. Now that Russia has delivered S-300s Iran will be under pressure have to reveal if it believes its own propaganda about which system is superior.
The original S-300 was known to NATO, during the Cold War, as the SA-10 and it entered service in the late 1970s and was upgraded several times since then. One major upgrade came to be called the SA-12 and it entered service in the late 1980s. Finally, there was the SA-21, which was so different from the original S-300 that it was given a new name by the Russians: the S-400. These systems began entering service, slowly, in 2007 and one battery was sent to Syria during 2016 to protect Russian troops there.
Each S-300/400 battery consists of 4-8 launcher vehicles (each with two missiles, plus two reloads). There are also radar vehicles and a command vehicle. The S-300V/SA-12 missiles had a range of 75 kilometers and were considered somewhat similar to the American Patriot systems. Later models of the S-300V had some capability to shoot down short range ballistic missiles. The SA-10/12 launcher vehicle also contains a guidance radar. The most recent version of S-300 (S-400) is supposed to be (according to Russia) superior to the American Patriot. But while the Patriot has over two decades of combat experience the S-300 has none.
Meanwhile Bavar-373 is not the first anti-aircraft missile system Iran claims to have developed. In 2013 Iran announced it had built a factory to produce the Sayyad-2 anti-aircraft missile. This is an upgrade of the Sayyad-1, which was based on the old (1950s) Russian SA-2. Sayyad-1 entered service in 1999. Both Sayyad 1 and 2 copied much from the Chinese HQ-2, which is itself an upgrade of the Russian S-75/SA-2 system. Sayyad-2 appears to have incorporated technology from the American HAWK and Standard surface to air missiles.
Sayyad-2 is a two ton, two stage anti-aircraft missile with a maximum range of 80 kilometers and max altitude of 20,000 meters (65,000 feet). The Sayyad-2 has better electronic countermeasures than Sayyad-1 but it is still dependent on the ground radar for guidance to a target and is vulnerable to electronic interference. Sayyad-2 is believed to have a more effective warhead. None of the Sayyad missiles has been in combat and test firings have not been impressive.
The Chinese HQ-2 has been in use since the late 1960s and has been upgraded several times with modern electronics, an improved warhead, better rocket motors, and more maneuverability and turned it into a much more effective HQ-2 early in the 21st century. Iran has been getting military technology from China since the 1980s. This apparently included the tech for the solid fuel rocket motors used by the Sayyad-2 and possibly some of the electronics. If an attacker does not have good electronic countermeasures the Sayyad-2 could be quite effective. China also has lots of S-300 and may have sold or leaked technical data on that system to Iran.