[Goose]

Meanwhile, the Russians have shot down an Azerbaijiani Airlines passenger flight, probably mistaking it for a Ukrainian drone.

https://www.reuters.com/world/asia-pacif...024-12-26/

The long periods of "track unknown" in the map point to the aircraft GPS not supplying flight data during that interval. There are three possible reasons for this. One is that Russia was jamming the GPS signal. Another is that Russia was jamming the ADS-B frequency. The third would be that the aircrew turned off the transponder. There is no reason to believe the aircrew would turn off the transponder ("strangle the parrot") during a legitimate flight. The secondary radar identification is there to allow the ground monitors to know who the aircraft is. Even without GPS the ground air traffic control (ATC) should have a range and bearing to the aircraft from the transponder response to the interrogation doublet. Russian ATC knew (or definitely should have known) who the aircraft was and more or less where it was. They also would know its altitude (barometric at a minimum). The pilots would undoubtedly have contacted Russian ATC as soon as they got into the Russian ADIZ. 

The Russian air defense network quite possibly didn't have that information. It also may be that the Russian air defense (Pantsir has been mentioned) was operating in an "automatic" mode. Of course, if that was the case the Russians should have closed the air space and issued a NOTAM to that effect. Periodic broadcast of that fact also should have been made on the local ATC frequencies and possibly 121.5. Russia obviously doesn't follow international norms, so it isn't surprising they did not in this case. Just another reason they are dangerous.

[Goose]

Meanwhile, the Russians have shot down an Azerbaijiani Airlines passenger flight, probably mistaking it for a Ukrainian drone.

https://www.reuters.com/world/asia-pacif...024-12-26/

The long periods of "track unknown" in the map point to the aircraft GPS not supplying flight data during that interval. There are three possible reasons for this. One is that Russia was jamming the GPS signal. Another is that Russia was jamming the ADS-B frequency. The third would be that the aircrew turned off the transponder. There is no reason to believe the aircrew would turn off the transponder ("strangle the parrot") during a legitimate flight. The secondary radar identification is there to allow the ground monitors to know who the aircraft is. Even without GPS the ground air traffic control (ATC) should have a range and bearing to the aircraft from the transponder response to the interrogation doublet. Russian ATC knew (or definitely should have known) who the aircraft was and more or less where it was. They also would know its altitude (barometric at a minimum). The pilots would undoubtedly have contacted Russian ATC as soon as they got into the Russian ADIZ. 

The Russian air defense network quite possibly didn't have that information. It also may be that the Russian air defense (Pantsir has been mentioned) was operating in an "automatic" mode. Of course, if that was the case the Russians should have closed the air space and issued a NOTAM to that effect. Periodic broadcast of that fact also should have been made on the local ATC frequencies and possibly 121.5. Russia obviously doesn't follow international norms, so it isn't surprising they did not in this case. Just another reason they are dangerous.