Any aircraft ini files that were created with SP1 will work fine with SP1b. ini files created prior to SP1 should not be used with SP1b... (if you have any doubts, just delete the aircraft ini file and let the sim regenerate it for you!) DEVELOPMENT HISTORY:===================04AUG11: RTM 1.00.288510AUG11: 1.00.2904 - HotFix Added15AUG11: 1.00.2916 - RTM & HotFix Updated16AUG11: 1.00.2922 - RTM & HotFix Updated23SEP11: 1.00.2987 - RTM & HotFix Updated28OCT11: 1.00.3057 (SP1) RTM & SP1 Patch Released. Syncs with 600/700 Releasehope this helps some of us cause it has to do with the ini filesgood luck everybody and thanks PMDG Ronny