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zetato
18th Dec 2016, 09:25
Hi all, my question is for a 737NG pilot, and is related to the planning phase on ground.
I'm using a 737NG simulator model, usually a 738 but I think it should be the same for the other models, and what I need to know, is if after the insertion of the route in the CDU, is possible to insert some constraint on some waypoints for the climb and for the descent phase, in such a way the plane would reach a certain altitude passing a point during the VNAV climb (and continue to climb), and, after the cruise phase, it would start the descent, passing another waypoint at predefined altitude constraint, during the descent (and continue the descent).
At the moment, the model i'm using cause a mess if I try to insert a constraint in the LEGS page on a point of the climb, for example, if I have a CRZ ALT of FL370, TIDKA fixpoint is computed at FL350 and I try to insert /FL335 in the LEGS page on the corresponding RSK, It computes a descent starting some miles prior to TIDKA and an End Of Descent over the point, confusing the rest of the vertical profile.
Something similar happens if I insert a constraint in a point of the descent.
I think it should be normal and easy to adapt a vertical profile during the flight plan insertion phase, but I need a confirmation from you.

Chesty Morgan
18th Dec 2016, 09:36
Try putting FL335 as your initial cruise level then reset it to FL370 at TIDKA.

zetato
18th Dec 2016, 10:04
Hi, thanks for the answer, yes, I'm currently using that or other workaround method, I'm just interested to know if in the real 737NG is it possible to do a "personalized" vertical profile in the planning phase on the CDU while still on ground, also to be sure to have a completely corrected fuel comsumption computation.