Explaining the "black line" on Flight Radar tracking:
Here's a great, basic explanation of how Multilateration (MLAT) and ADS-B transponder signals work.
@Borrowed7Time@flightradar24
Department of Defense
Missle Defense Agency
Gulfstream G550
x3 out of Honolulu tracking S
N551HA/HALO51
N552HA/HALO52
N553HA/HALO53
@Borrowed7Time@FMilcoms@thenewarea51@norb420