First post here. Before my question, I’d like to say thanks for this awesome site. I work at the Skyhaven Airport (9k4). We have a pretty intensive flight training program and I use FA to track our flights (23 Skyhawks, 2 Beech Duchess, 3 Cutlass RG’s, Seneca, Baron, King Air)

I don’t want to get off topic of my question… anyways, I notice when you track a specific flight, there is a column that says “Groundspeed” when actually you file a flight plan with FSS you give them “True Airspeed” Why does the column say groundspeed, when it is actually True Airspeed?

I know that when the flight is airborne, the right column is the aircraft’s groundspeed, but not on the filed portion





Ground speed is what the ATC radar can “see”. In a zero wind environment, your TAS will equal your GS. For filing purposes, since you don’t know the extent to which the winds will affect your groundspeed, you file based on true airspeed. The purpose of the flight plan is not to know exactly where you will be when, but to have an idea of where you are coming from, going to and approximately how long and what routing you want/or are assigned for the purposes of traffic flow control and search and rescue.


While you’re techncially correct, CMSUFlight, the enroute speeds are groundspeeds and to minimize clutter and confusion we put the filed airspeed in the same row.


Fair Enough, THX!