Dear Maxime, Dear Goran, Thanks. As it is the only aircraft file that is behaving this way , i think it is unlikely to be the preferences, but i will do it and then report. ( although i am reluctant to change the configuration of this rather 'heavy' sim i have. i will take screenshots to. i noticed that the instruments had dissapeared at the crash. My scenery is very heavy, on both pc's in use. the master 'instruments'- pc has only one hd screen, the scenery- textures do get misty after 20 minutes, but no problem for the flying because: the second 'scenery' pc has plenty of graphic card power and never gets tired. it is the master (instruments) pc that crashes. one thing that i do which is a little trick ( i dont know if this has to do with it) is that the scenery pc does NOT have the aircraft file, in order to avoid the 3D appearing over my scenery. it replaces it automatically with the standard cirrus aircraft. i will return with more info once i have tested. Thanks! David (ps : It was Cameron who directed me to this forum)