This map shows approximate combat radius of the Russian Air Force in Syria. At the moment, the Russian groupping is located in the airbase in Latakia. Nonetheless, if Kremlin decides to expand its air campaign in the region, it has a possibility to use other airbases controlled by the Syrian Armed Forces.
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Interesting ,but in fact SU-25 combat radius is about 750 km (with 2×800 L external fuel tanks). From what I saw ,SU-25´s in Syria always use those external fuel tanks.
Where is Sarah Conner?