Notes:Winds Aloft Forecast for KBIL at 12,000 270@79kts.
The first picture is of an FAA radar replay courtesy of my friends at the tower/approach control. The radar updates at 6 second intervals, so it captured a higher GS than FlightRadar24 which saves data in 10 second intervals. The highest GS I saw in the aircraft was 300mph (261kt) but I have no evidence for this.