Hello.
Came over an odd problem during cruise which I have never had on any of my numerous previous flights.
As I was crusing along at FL380, I suddenly noticed (after cruising for an hour) that ATS was flashing "FAIL", I cleared the message and tried to re-engage the ATS without any luck. Going to the FMS, I noticed that all the thrust limits was gone for no apparent reason. With blank I mean that TO, CLB and CRZ had no numbers in them, no text or numbers, just blank. However MCT had a number in it, but selecting it just resulted in it being automatically deselected.
Once I started my decend, reaching about FL350 all my thrust limits restored and I could resume the usage of ATS.
So I am a bit confused of what went wrong for this flight, any ideas?