The best way to tell if it's a false flag operation is to see how much this event will be spread in the Russian media.

They've lost tons of equipment and had bombings deep in Russian territory, mostly affecting their oil production which could be perceived locally as Russian military inferiority.

So when this starts being on blast for every channel and frequency - you can be sure it's a false flag.

If they bury this like any other Russian military failing, then it's probably real.

Edit: ISIS claims responsibility, but Russia is still trying to blame Ukraine, which is kind of a false flag?