For today, the Russian combined air group in Syria numbers about 50 aircraft: four multirole fighters Su-30SM, six strike fighters Su-34 and 12 Su-24M, same number of attack aircraft Su-25, as well as multirole Mi-8 and strike Mi-24 helicopters.
According to a source in the Russian defense ministry, major costs for the military operation are related to provision of aircraft fuel and arms (they are delivered by large landing ships and military transport airplanes). Also, money are spent on maintenance of equipment in serviceable conditions considering its active employment, as in Syria Russian aircraft normally perform over 20 flights per day.