List of aviation shootdowns and accidents during the Syrian civil war

During the course of the Syrian Civil War aviation shootdowns, incidents and accidents have taken place between different state and non-state actors. According to the website Strategy Page, by mid 2013, nearly a hundred fixed-wing and over a hundred helicopters were lost. Some 400 aircrew have been killed, captured, or missing.
Public observation via Google Earth of Syrian airfields shows a decreasing number of airframes parked in the open in contrast to the increasing number of recorded air sorties. The hubs of Syrian Air Force basing activity prior to and during the Syrian Civil War have been the airfields at Aleppo, Damascus, Latakia and Hama.
However, most of the losses can actually be attributed to paper write-offs: usually when an armed confrontation starts, the paper numbers about the national armed forces circulating before the war account for several vehicles which were actually abandoned or not serviced or in a general poor maintenance status. In the Syrian example, MiG-23MS, older MiG-21 versions, Su-20 (which is an older variant of the active Su-22), nearly all the MiG-25 and several other air-frames were already in disrepair before the war started.
Due to external support by Iran and Russia, the combat readiness of the Syrian Arab Air Force actually increased over the years of the civil war, with the resources being rationalized towards useful assets and wider availability of service and parts for the remaining air-frames.
As usual during an armed confrontation, it is impossible to determine the cause of every single crash, because opposing parties may claim the aircraft was shot down by their forces, while the side flying the aircraft claims it was accidental. In some instances, even the presence of a video does not clarify what happened, since a flash may be due to an antiaircraft shell or an engine explosion.
The list below includes both manned and unmanned aircraft.