Hi Jack,
all you have to do is start Free Flight, chose any of the airports you want to add to your airbases.dat and go fly.
As soon as you aircraft is sitting at the head of the runway, hit SHIFT+Z, you will see on your upper left corner airport coords and framerate, if you hit the combination again you'll see just framerate, one more and you'll get just the coords.
The info also includes the height (A) in feet and the heading (H) in degrees. You must subtract from the height about 4' 8", because the height displayed is the one of your viewpoint, your eye level so to speak, the ground level is almost 5' below you when you are sitting in a fighter plane.
Write down the info displayed and then enter it in a new airbase.dat entry as follows:
[runway.xxx] --------------------> xxx=the next available
id=--------------------> xxx=the next available (unique!)
name= -------------> airfield name displayed in Map Info
base_lat= ----------> latitude
base_lon= ---------> longitude
base_alt= ---------> base altitude in feet
heading= ----------> heading degrees
allegiance= --------> you might enter 0 for no allegiance or, in this case, 1 for GB as all England airbases never changed allegiance
units_across=......
from now on you might copy the data from the previous entry, it shouldn't cause any problem (at least it never did on my pc).
And so on with the other airports. Just be careful: do not delete the End of File marker at the bottom of your airbases.dat, that little square thingy is vital for proper operations of your airbases.dat.
On more advice, check into Achim's UK airbase pack and the British airbases included in Achim's Various & Various 2 ETO airfields. Some of the most famous 8th USAAF airbases, like Boxted and Leiston, are included.
Although Ian Elliot's sceneries are beautiful, they aren't GSL-ised as Achim's ones.
GSL-based sceneries offer a better framerate performance.
Cheers!
KH :ernae:
