Hi,I have a question about the Vnav function with the PSS FMC. The fmc calculates the optimal and maximum cruising altitude. But how do I get Vnav clims automatically from the cruising FL to the optimal FL?Hope someone knows.Thanks

It doesn't. The MCDU only provides you with optimal cruise altitude information. Nothing automatic occurs on the Airbus in this regard (or on a Boeing for that matter). You must explicitly change the cruise altitude to a new target altitude and invoke a selected or managed climb mode.Cheers,J