Note:  This  procedure  involves  editing  a  game file; create a
backup copy of the file before proceeding. Also, have the game patched
to  the  latest version. Use a text editor to edit the "airlines" file
in  the "\program files\global star software\airport tycoon 3\data\db"
directory.

All airlines:
     Set  the  value  for the "QUALITY" line to "1". All airlines will
now be unlocked.

All planes:
     Change the date value of each airplane to "1/1970".

All buildings:
     Change  the  date value after the "destroy" line of each building
to "1/1970".

Free items:
     Also, change the value after the word "MONTHLYCOST" to "0".