FMC VNAV, transition altitudes: Why are they always the same (climb and descend)?

Question

Is it a normal behavior that the VNAV Descend Transition Altitude is always same as the Climb one?

I think we should be able to set different altitude, for example if we take off with X transition altitude and we will land over Y transition altitude..

Answer 1

No it isn't. in a normal MCDU you have departure area transition altitude (from low to high, local QNH to STD QNH 1013.25 hPa/29.92 InHg) and in arrival area which might be in other place in the world you have a transition level from high to low, STD 1013.25/29.92 to local altimeter setting accordingly to local QNH.

it is annoying that such an important security parameters is ignored.
We really need two datarefs for that purposes : transition altitude and transition level and two boleans
one for altimeter shows real altitude(true/false) and one for current flight level mode (true/false)