Iran has developed a reputation for launching some unconventional naval vessels, some of them downright strange — at least when compared with their equivalents elsewhere in the world. Its latest offering, the Zagros, is very much in keeping with this trend: a surveillance ship based on a corvette hull, an unorthodox approach for a type of vessel that would typically be converted from a commercial hull.


Iran unveiled its first domestically built signals intelligence (SIGINT) ship, the Zagros, yesterday. According to the state-run news agency IRNA, the ship has now officially joined the country’s naval fleet. “The Zagros signals intelligence ship will be a vigilant eye for the Iranian Navy deep into seas and oceans,” the commander of the Iranian Navy, Adm. Shahram Irani, said in a statement.

Iranian state media released footage of the vessel under construction, underway at sea, as well as Iranian Armed Forces Joint Chief of Staff Gen. Mohammad Bagheri and other military personnel visiting the ship and meeting with its crew.
In common with other SIGINT ships, the Zagros is equipped with electronic sensors to collect, decrypt, and analyze radio-frequency signals from hostile or potentially hostile emitters. Antennas for these sensors are housed in prominent ball-shaped radomes arranged around the top of the superstructure, with seven in all, of three different sizes, with the smaller ones likely to house satellite communications systems.

Meanwhile, an apparent radio direction-finding antenna mounted on top of the ship’s mast has been noted as being very similar to a system of this kind marketed by China.
Iran’s semi-official Tasnim news agency has said the Zagros is also able to conduct cyber operations but provided no further details.

In other respects, however, the Zagros exhibits some significant differences from more usual surveillance vessels.
The state-run Fars news agency describes the new vessel as an “intelligence destroyer,” reflecting the fact that the Zagros was built using a converted hull from a Mowj class warship, five of which are currently in service. These domestically produced vessels are classified as destroyers by Iran, but in terms of size and armament are much closer to light frigates, or corvettes, although the distinction between warship types — especially of these kinds — is increasingly blurred.
The Mowj class has a displacement of around 1,500 tonnes, a length of 311.7 feet, and a beam of 36.4 feet. The warship has a speed of around 30 knots and is operated by a typical crew of 140.

Specifications are currently not available for the Zagros, but the dimensions are presumably very similar.
Based on the imagery published so far, the Zagros has no armament fitted, in contrast to the original Mowj class vessel, which is armed with a 76mm main gun, a 30mm close-in weapon system, Mehrab surface-to-air missiles, Noor or Qader anti-ship missiles, and torpedo tubes.
However, unlike the original Mowj class, the Zagros has a flight deck and a hangar, able to accommodate a helicopter. Available imagery shows the ship embarking an Agusta-Bell AB212, a version of the Bell 212 built under license in Italy and equivalent to the U.S. military UH-1N.

An embarked helicopter is an unusual feature of a SIGINT ship, suggesting that the vessel is intended to undertake other missions, as well, or perhaps the rotorcraft is intended simply to provide a means of logistical support when at sea for extended periods. On the other hand, a helicopter could also be used to provide a degree of force protection, especially important in the absence of other weapons aboard the ship — although some lighter weapons may still be fitted at a later date. Another option would be to outfit the helicopter with a sensor payload, increasing the overall area in which intelligence can be collected and providing a rapid means of gathering it from points of interest.
So far, Iran has relied on adapted smaller commercial vessels to gather SIGINT and it’s not entirely clear why it took the opposite approach with the Zagros. Other countries typically take a commercial hull as the basis for a spy ship, since this offers considerable space for sensors and sensor operators as well as significant power-generation capabilities. Since their main role is peacetime surveillance, the combat capabilities of such vessels are very much secondary. Using a commercial hull also results in a ship that is far more efficient to build and operate, and which is more easily supportable once in service.

However, given that Iran has previously converted commercial hulls into warships — notably its fleet of “forward base ships” — such an approach is perhaps not entirely surprising. Above all, it suggests that Iran is willing to make use of whatever hulls are available to meet its naval requirements. At the same time, presuming the Zagros is built to a higher naval standard — which is not necessarily a given — it would presumably be more survivable than a commercial hull.
Once established in service, the Zagros should offer Iran a valuable means of gathering intelligence on opposing forces not only in the Persian Gulf but also farther afield, including into the Arabian Sea and Red Sea. Here, it could be especially useful in the context of the growing hostilities between Iran and Israel, as well as the anti-shipping campaign currently being waged by the Iran-backed Houthi militia.

In recent years, however, Iran has also demonstrated a growing ability to project naval power over much greater distances. With this in mind, the Zagros might even end up making deployments to the Mediterranean Sea, from where it could also observe Israeli and other countries’ naval activities.
Given the antagonism between Iran and the United States, the Zagros could also be used to monitor U.S. Navy carrier battle groups operating close to Iran or its interests.
With its new signals intelligence vessel, Iran has once again taken an unexpected path to expandings its naval capabilities. However, given the current tensions between Iran and its adversaries, and the growing number of theaters in which these are being played out, the Zagros looks like it could be headed for a busy career.
Contact the author: thomas@thedrive.com