For the second time in recent days, Turkey has reportedly intercepted Russian or Syrian aircraft in or near its airspace. NATO has rejected a Russian explanation that the first incident involving a Russian Su-30 over Turkey's Hatay region October 3-4 was an accident. The Turks have said that the Russian intruder locked its radar on a Turkish F-16 for a full five minutes. That is often read by combat pilots as a sign of hostile intent. If true the explosive potential is great as a pilot seeing that a potential adversary has locked on him as a target might well fire in self-defense.
The second incident October 5 raises other questions. Initial Turkish reports identified the intruder as a MiG-29 of unidentified nationality and say it also locked its radar on at least one of a flight of eight Turkish F-16s performing combat air patrol along the border. The radar lock lasted for and a half minutes. Again, a radar lock suggests the Turkish aircraft is a potential target.
Western reports of Russia's buildup have not reported that Russia has deployed any MiG-29s to Syria, but the Syrian Air Force flies them. There are superficial resemblances between the Su-30 and the MiG-29, and a misidentification is possible, but why should the nationality be unidentified?
One report in the aviation press a few days ago noted that a video circulated by Russia Today (much as I dislike quoting Russia Today) seems to show Russian aircraft at Latakia air base with the prominent Red Star on the tail painted over. Why, since the Russians acknowledge they are flying bombing missions? Is it to create uncertainty over whether Russian or Syrian aircraft are responsible for specific missions? (Syria's Air Force is Soviet or Russian-built.) In any event, unidentified aircraft violating airspace in a combat zone and radar locking on Turkish aircraft is a recipe for an explosive situation.