Difference Between Air and Ground Mileage

[your_dreamguy]

Hello,

On the Flight Summary Page of our FMS, there are two columns for our flight. One gives an Air Mileage Distance and the other gives a Ground Mileage Distance. The mileage numbers are different and I was wondering if anyone knows what the difference between the two numbers is?

Thank you

 

[xjcaptain]

I believe that the "air-mileage" number accounts for winds, while the "ground-mileage" number does not. For example in a headwind you will take longer to complete the flight so you will "travel" through more air distance. With a tailwind the air-distance number will be less than the ground distance number since the wind is pushing you along.

 

[five-alive]

If youre doing 400 KTAS and have a 100 knot headwind, your air mileage will be 400 and ground mileage will be 300 after 1 hour

 

[siucavflight]

If youre doing 400 KTAS and have a 100 knot headwind, your air mileage will be 400 and ground mileage will be 300 after 1 hour

Yes, good answer.