An Embraer Legacy 600 associated with Wagner Group head Yevgeny Prigozhin crashed Wednesday afternoon near Tver after departing from Moscow.
Though this aircraft is equipped with ADS-B, it was tracked by MLAT—likely due to GNSS interference/jamming in the area. The “D” in ADS-B stands for dependent, meaning dependent on a position report from a GNSS source (GPS, GLONASS, etc) for proper position reporting. Without this the aircraft continues to send data, but not its precise location. In the absence of position updates from the aircraft, Flightradar24 uses Multilateration (MLAT) to calculate the aircraft’s position based on the reception of signals by multiple receivers in the area.
Receivers in the Flightradar24 network first received data from the aircraft at 14:46 UTC. We were able to calculate positions from 14:59 UTC to 15:11 UTC as the aircraft climbed to a cruising altitude of 28,000 feet. The aircraft continued to transmit data until 15:20:14 UTC.
Even though the aircraft was not transmitting position information, other data like altitude, speed, vertical rate, and autopilot settings were broadcast. It is this data that provides some insight into the final moments of the flight.
Parsing RA-02795 Extended Mode S data
After leveling off at 28,000 feet at 15:10 UTC, the aircraft continued in level flight at consistent speed until 15:19 UTC at which point the vertical rate decreases dramatically and the aircraft descends briefly before climbing to a maximum altitude of 30,100 feet before descending back to roughly 27,500 feet. It again climbs, reaching 29,300 feet before leveling off once again. It then descends, with the final data received at 15:20:14 UTC at an altitude of 19,725 feet. The altitude graph below shows the final 32 seconds of received altitude data.
The chart below plots the aircraft’s reported vertical rate in feet per minute for the duration of the flight.
The aircraft continued to report data until 15:20:14 UTC when it transmitted an altitude of 19,725 feet.