Why can't I change the altitude on the F-PLAN page in the MCDU of the A350 and A380? The system maintains FL430 throughout the cruise level.
A350 and A380 cruise altitude problem
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- Official Post
FL430 is too high...
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FL430 is too high
He means he cant change the altitude on the F-plan page on the a380 and a350
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FL430 is too high...
You didn't understand what I meant.
I'm referring to the fact that the programmed cruise altitude cannot be changed in the MCDU. At each waypoint, the system maintains FL430. I did NOT choose FL430. It stays there in the MCDU on the F-PLAN page in an immutable way. It is not possible to change it.
For example, on my last flight between VTBS and RJBB, the programmed cruise altitude was FL370 and then a stepclimb to FL390 (flying with the A380). However, even though I selected the FL370 altitude in the MCDU, the system does not update it on the F-PLAN page. It maintains FL430 for all waypoints at the cruise level. It is not possible to change them, not even one by one directly; the system simply does not accept changes. This ends up causing some problems, for example: on the ACTIVE/PERF page, where we have the flight phases (T.O, CLB, CRZ, DES, APPR, GA) the system does not leave the CLB page, even when we stabilize the flight at cruise level. This is a problem because the flight computer understands that we have not yet reached cruise level, since it erroneously establishes FL430 against the will of the pilot in command. So it spends the entire flight believing that the aircraft is still in CLIMB mode. This happens on both the A350 and the A380.
Another reflection of this error is that on the altitude and route graph on the navigation display, the aircraft is always outside the altitude line, for obvious reasons, as I have already explained.
