Holds and ETA computations


#1

flightaware.com/live/flight/COA456 is currently holding due to a line of T’storms affecting KBWI.

Progress time is steadily ticking down, but the distance to the airport is not based on the hold.

Is the arrival time based on air miles travelled minus total miles?

If so, then in the above flight, seems that 171 miles won’t be covered in 6 minutes?

Seems that the distance from the airport divided by speed should compute to the ETA inspite of the hold?

Of course, no one knows how long the hold would take place, but the 6 minutes remaining would not occur based on the above information.

Allen

EDIT - Looks like a bug in the ETA now, since now it shows arrived 17 minutes ago, and yet it’s still holding.


#2

Time remaining is departure time + estimated time enroute - current time OR and ETA update that we receive from the FAA (which usually come every time the ETA changes by 1 minute or more).

Distance travelled/remaining is straight line distance from the current point to the origin/destination.

FA doesn’t calculate any of the times (based on distance/speed), but we do calculate the distances.