The Israeli foray, into Syrian airspace earlier this week has apparently mystified commentators, some of whom have speculated that it was a navigational mistake.
Probably the real reason was to test the capability of a newly-installed anti-aircraft system that the Russians have sold to both Syria and Iran. The system failed to down any of the Israeli jets which failure has no doubt embarrassed the Russians, frustrated the Syrians and caused deep concern among the Iranians who were surely hoping it would give some measure of protection against an American strike on their nuclear facilities.
The purported Israeli air force flights over the Pantsyr-S1E site established that the new Russian missiles, activated for the first time in the Middle East, are effective and dangerous but can be disarmed. Western military sources attribute to those Israeli or other air force planes superior electronics for jamming the Russian missile systems, but stress nonetheless that they were extremely lucky to get away unharmed, or at worst, with damage minor enough for a safe return to base.
The courage, daring and operational skills of the air crews must have been exceptional. They would have needed to spend enough time in hostile Syrian air space to execute several passes at varying altitudes under fire in order to test the Pantsyr-S1E responses. Their success demonstrated to Damascus and Tehran that their expensive new Russian anti-air system leaves them vulnerable.
There's more on this incursion at the DEBKAfile link.RLC