Copied from >>5031265 (general bread #6424)

PlaneFags,

Seeing a few U2catches lately and excitement about being at 60K altitude. Know that all military flight that go very high only ever show 60K feet (actually FL600) for altitude. They go MUCH higher but ATC as well as ADSB will only display FL600. They are controlled by ATC using classified altitude codes where they operate in that range. No sauce, I am the sauce since I was one of the guys that handle them in Oakland ARTCC and elsewhere. If you see FL600 know the real altitude is much higher.