Disappear as in some of the graphics went missing for a brief moment? Then yes, it happens now and then. I've noticed it happen when the PS3 is under a lot of work, for instance at Nürburgring with time lapse during the morning hours when there's a lot of processing on the lighting. It's probably the same with the Indy endurance, if the PS3 has been working more or less hard for 50 laps.
