Disparity between FlightAware, Garmin watch, and Garmin transponder distances

[Mike A]

I just got back from a long cross country to Florida and the distances shown by FlightAware, my Garmin watch are very different from the ForeFlight output from my Garmin GTX345.  ForeFlight is showing 130 miles shorter than the other two, which are in general agreement. There are significant differences in all the flights now that I’m looking back. Any ideas why?

[toto]

Random guess … one was showing distance to next waypoint and the other two were showing distance to destination?

[Mike A]

Statute vs nautical. ForeFlight’s default distance setting is nautical which explains why it’s short. 
 

The more you know. 

[toto]

11 minutes ago, Mike A said:

Statute vs nautical. ForeFlight’s default distance setting is nautical which explains why it’s short. 
 

The more you know. 

I don’t have big enough tanks to get a 130-mile discrepancy between statute and nautical..

At least, not without some serious 201er hypermiling

 

 

[Mike A]

[David Lloyd]

If I were guessing, the chart showing 734 miles is statute miles and includes the waypoints that add slightly to the distance.  The other being 615 nautical miles in a straight line from PBI to RNC.

 

[Mike A]

8 minutes ago, David Lloyd said:

If I were guessing, the chart showing 734 miles is statute miles and includes the waypoints that add slightly to the distance.  The other being 615 nautical miles in a straight line from PBI to RNC.

 

They are both track logs

[David Lloyd]

I don’t know but in Garmin Pilot KPBI to KRNC direct is 615.2 nautical miles.  Putting in a couple waypoints to approximate what your map shows, say NRB near Jacksonville and HRS right near the intersection of NC GA and TN, and changing to statute miles, Garmin Pilot comes up with 734 statute miles.