National Resistance Center under the SOF of the Ukrainian Army.explained how many drones can iran produce on request for the russian federation, and how they are delivered to the russian armed forces for further use against Ukraine.
Ukrainian researchers suggest that iran’s capabilities allow to produce up to 150 drones per month, without specification, though, which exactly type is meant, whereas russia is interested in several technologies.
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First and foremost, Shahed-131 and Shahed-136 kamikaze drones, which have been used en masse to strike Ukrainian civilian infrastructure; Mohajer-6 attack drone and ordered not so long ago Arash-1 and Arash-2 kamikaze drones.

The figure on 150 drones per month likely refers to the production of Shahed-type drones in the first place which are made of cheap civilian use goods. To reach such production rates, three countries are involved in the process: iran itself, Tajikistan and Syria.
The fourth supposed accomplice is belarus. Lukashenko ordered the "558th Aviation Repair Plant" to speed up with the development of its attack drone and loitering munition program. There is a high chance this is a disguise for the production of drones marked "Geran-2" out of iranian-supplied parts using the capacities of belarusian defense industry.

For the delivery of the drones, russians and iranians use two ways of transportation: by air and by sea. Four companies are involved: Iran Air (state-owned, controlled by the ministry of infrastructure), Mahan Air (officially, privately owned), Pouya Air (belongs to Islamic Revolutionary Guard Corps), and Saha AirLines (iranian air force). The Pouya Air is convenient not only because of similar "ideological beliefs" but also since the core of the aircraft park is constituted by russian-made Il-76 planes.
And the Mahan Air company is generally an underling of the IRGC, registered to a dummy person. Although, as indicated by the TTS website, this airline operated flights on the Kyiv-Tehran route in 2016-2017.

The sea scheme is established as follows. The main route runs through the Caspian Sea, provided by the shipping Iranian Industrial Company, once again, controlled by IRGC. The departure point is the Iranian port of Bandar Anzali, the destination is the russian ports of Astrakhan or Makhachkala. According to the documents, during the sails, iranians are delivering "spare parts for civil aviation" to russia.
There is also a "side route", from Tartus is Syria through the Bosphorus and the Dardanelles to the temporarily occupied Crimea. Specialists of the National Countermeasures Center assume that such flights take place according to the following scheme: ships with stolen grain go to Tartus, and after unloading, "flying mopeds" are loaded onto the grain trucks. Although such assumptions still need to be tested in practice.
The Resistance Center researchers assume that the order of action is, first, the vessels go to Tartus loaded with grain stolen from Ukrainian silos, and after it’s unloaded, the grain carriers are filled with drones instead. Though the specialists still need to confirm this information, as they noted.
The same way, the researchers assume, iran will try to hand over Zolfagar missiles straight from the Syrian plant to russia, by sea from Tartus.

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