Did Iran convert an old ground-launched artillery rocket into a new air-launched ballistic missile?

A YouTube video, allegedly taken by Iran's Islamic Revolutionary Guard Corps (IRGC), shows an Iranian Su-22 – a Russian-made fighter-bomber — launching what appears to be a long, slender missile (the launch begins at about the 30-second mark in the video). Pro-Iranian media claims the weapon is an air-launched version of the Fajr-4, a big, long-range, truck-mounted artillery rocket.

A Russian defense news site compared photos of the missile in the Iranian video to the Fajr 4 – and they indeed look similar.

What exactly is a Fajr-4? It's a 333-mm rocket that's part of the Fajr family of truck-mounted multiple rocket launchers, comprising unguided rockets in 240-mm and 333-mm calibers and with ranges of up to 30 miles. Some are based on Russian, Chinese and North Korean designs, with Hezbollah using the Fajr 3 against Israel in the 2006 Lebanon War.

In a 2007 report on the Iranian military by the U.S.-based Center for Strategic and International Studies, the Fajr-4 – also known as the Shahin-1 – is described as a "a trailer-launched 333-mm caliber unguided, high-explosive artillery rocket. Two rockets are normally mounted on each trailer, and they have a solid propelled-rocket motor, a maximum range of 75 kilometers [46 miles], and a 175-kilogram [386-pound] conventional or chemical warhead. The Shahin evidently can be equipped with three types of warheads: a 180-kilogram high-explosive warhead, a warhead using high-explosive submunitions, and a warhead that uses chemical weapons."

There is no footage of the rocket motor actually igniting.

This isn't the first time that Iran has turned a ground-based rocket into an aerial weapon. The Oghab, a 230-mm artillery rocket, may have been modified for launch from Iranian F-14 and F-4 fighters. But there are a few interesting twists to the Fajr-4 story. The Iranian video shows the rocket being dropped from an Su-22, and then the rocket falling through the air – and then a big explosion on the ground. But there is no footage of the rocket motor igniting. This could mean a static airdrop test, which in turn suggests the weapon is far from being operational.

More interesting is the description of the air-launched Fajr-4 as a guided weapon, though the ground-launched version is unguided. An air-to-surface missile would certainly have a guidance system: trying to destroy targets with giant unguided rockets would require the launch aircraft to fly dangerously close to the target.

However, Iran has developed a kit that turns unguided surface-to-surface rockets into guided weapons. The U.S. Joint Attack Direct Munition (JDAM) takes the same approaching by affixing a GPS guidance kit to iron bombs to turn them into smart weapons.

Whatever we know about the Fajr-4, we know it's not an air-launched ballistic missile like Russia's Kinzhal, a nuclear-tipped hypersonic (faster than Mach 5) missile that may be too fast for Western air defenses to stop. Fajr-4 seems more like an old Katyusha-type rocket launched from an airplane.

Iran has a history of announcing weapons with more bark than bite.

Iran does have a history of announcing weapons with more bark than bite, such as a stealth fighter that apparently is neither stealthy nor much of a fighter.

Indeed, some Western experts aren't impressed with the new Iranian weapon. Anthony Cordesman, who coauthored the Center for Strategic and International Studies report, noted that the name "Fajr" covers both missiles and artillery rockets.

"We constantly see new announcements with new and sometimes duplicative names," Cordesman told Uncommon Defense. "Sometimes they are real and sometimes they simply are a way of hyping Iranian military power."