The Israeli Air Force's leading conjecture on the F-16 plane that was shot down by anti-aircraft fire on Saturday morning is that Syrian forces used a Russian made SA-5 Gammon medium-to-high altitude surface-to-air missile to intercept the Israeli aircraft.
Missile trails were seen in the central region of the country in the early hours of Saturday morning. It is possible that some Syrian SA-5 missiles fired in the barrage failed to lock onto the jet and flew off course, though there were no reports of any such missile falling in the region.
About two weeks ago, pro-regime Syrian armed forces threatened to strike Ben Gurion Airport in response to an attack on their soil they attributed to Israel.
According to IAF Chief of Staff Brig. Gen. Tomer Bar, pilots of the downed warplane did not have time to report the incident on the communications network before they bailed, as the missiles locked on and closed distance with the aircraft too quickly for them to do so.
The mission, in any case, was a "complete operational success," Bar noted, calling the large scale attack on Syrian aerial defense systems and Iranian targets in Syria "surgical" and emphasizing it was "the most extensive defense operation we have carried out against Syrian armed forces since Operation Peace for Galilee (1982 Lebanon War)"—the last time an Israeli plane was shot down.
Though he did not reveal what exactly were the targets the IAF attacked, he did note that Iran is working to implement surveillance systems in Syria against Israel.
"There's some contention between the desire to fulfill the mission and the matter of survivability. We will investigate what happened, but the teams' performance should be commended," said Bar, adding that the pilots successfully managed to fly the plane into Israeli territory before having to abandon it, and did so without risking civilian life.
Bar added that at no point was Russia involved in the operation and following interception.
"We informed the Russians about our activities, but I will not say at what stage of the operation," he said.
Yoav Zitun, Ahiya Raved, Liad Osmo, Hassan Shaalan, Ron Ben-Yishai and Elior Levy contributed to this report.