@mrbigbird
I have seen reports that claim the last two pings were at the same location which some suggested could mean it was on the ground.
Given that 59 minutes could have elapsed after landing before that second last pin the plane could actually have been on the ground for 2hrs 59 minutes.
So
if the above is true re. pings and
if they landed, then they landed between the 3rd and 2nd last ping. Take the arc and go backwards along the line of pings with an average speed based on time contact lost minus time of last ping?