Max Alt A320

[rudderrudderrat]

Hi Neupielot,

FCOM 1.22.20.28 Perf says:

"A maximum altitude using a 0.2 g buffet margin is also computed. It is not displayed, but the system uses it to limit CRZ ALT entry."

Normal displayed buffet margin is .3 g, but if you type your maximum requested FL into the Cruise Field when it shows say Max FL377, then it may accept FL 380 if its buffet margin is =>0.2 g.

Best make sure there is no forecast turbulence / wind shear though, else you will want to return to a lower FL. Otherwise refer to the performance graphs FCOM 2.5.20 Optimum & Max FL and open the little hidden picture at the bottom.