It is unlikely it ever got that high.
Yeah, I know, 'radar' and all that. Well, primary height-finding radar is not all that accurate, and FL450 is above the 777-200 capability, well above certified.
“Well, primary height-finding radar is not all that accurate, and FL450 is above the 777-200 capability, well above certified. “
The certified level is set to provide safety margins for maneuvering. I can’t find any numbers but I am sure that the 777 can get to FL450. It would take some time but they are still capable of positive climb rates at FL430.
just ignore my last ping - I see now the radar system was old and most likely it did not reach 45k. :)