According to the Pentagon, the regime soldiers, equipped with tanks, artillery and technical vehicles, were advancing on the SDF position, forcing the coalition to use the de-confliction hotline with the Russians in attempt to turn the regime troops back.
When that proved unsuccessful, coalition aircraft performed "strafing runs" near the regime positions, which halted their advance.
Following that incident, coalition aircraft observed the Cold War-era Su-22 fighter fly over the SDF positions.
"They saw the Su-22 approaching," Navy Capt. Jeff Davis,a Pentagon spokesman, told reporters Tuesday. "It again had dirty wings; it was carrying ordinance. They did everything they could to try to warn it away. They did a head-butt maneuver, they launched flares, but ultimately the Su-22 went into a dive and it was observed dropping munitions and was subsequently shot down,"
"Dirty wings" is a military term used to describe a plane carrying armaments. In "a head-butt maneuver, the planes fly just in advance of another to create heavy wake and get its attention," Davis explained.
Immediately after the Syrian Su-22 fighter jet dropped its bombs, two American F/A-18E Super Hornets, flying from the aircraft carrier USS George H.W. Bush, engaged, firing a AIM-9 Sidewinder — a short-range air-to-air missile — at the Syrian plane from about half a mile away, two US officials told CNN.
But the Syrian jet deployed defensive flares, causing the US missile to miss its target. The US pilot proceeded to fire off a second missile, an AIM 120 Advanced Medium-Range Air-to-Air Missile, which hit its intended target, downing the Syrian warplane and forcing its pilot to eject, the officials added.
The official said the US pilot saw the Syrian pilot eject and saw a parachute deploy, but the US believes the pilot would have landed in ISIS-controlled territory in Syria. The Syrian Armed Forces said in a statement that the pilot was missing.
"In 1987 we had the AIM-9P, which was designed to reject flares, and when we used US flares against it would ignore them and go straight for the target. We had the Soviet flares – they were dirty, and none of them looked the same – and the AIM-9P said 'I love that flare'.
(Terrible quality) video of USN F/A-18 shooting down Syrian jet this summer, and USAF shooting down RPA shown at #ASC17 pic.twitter.com/1FFlFDLsjJ
— Brian Everstine (@beverstine) September 18, 2017