An increased Russian presence inside Syria – including on some air bases – may limit the Israeli air force's ability to perform strikes against targets in the country that are connected to Hezbollah in Lebanon.
Since the Syrian civil war began in 2011, foreign sources have reported that Israel's military has performed a number of airstrikes against storage facilities and vehicle convoys which were to support Hezbollah's preparations for war against Israel.
The Syrian air force did not try to stop those strikes, with its inaction believed to be due to its fighter aircraft being in bad condition because of a lack of spare parts and bad maintenance.
With the increased presence of Russian personnel now in Syria, some of its aircraft – mainly RAC MiG-29s – may be put into service, and some could be flown by Russian pilots. Israeli sources note that Moscow also has deployed new sensors to the country which could detect aircraft invading Syrian airspace.
Moscow is also reported to be deploying the Pantsir-1 (SA-22) surface-to-air missile system to Syria, for operation by Russian experts.
The potential increase in the Syrian air force's defensive capability is a fact "that has to be considered very carefully", the sources note.
Source: FlightGlobal.com
