Originally Posted by
Italianinfrance
Hello, I mainly talk about A320 but I think it’s valid for every aircraft.
I’m quite the only one inserting the alternate routing on MCDU in order to have a valid route and some fuel predictions but I’m the only one that finds with little sense using some SIDs?
for example from MXP the alternate is many times LIN and our FPlans normally have as first point SRN, thus a SID going to the right, so generally people put this sid in the alternate routing. What I do is generally copy the final wpt of the missed approach and create the route from there…. In MXP means from 35L going to the left and this means a bit more consumption… Is it wrong ? Do you do something different?
Mostly agree with the above comments. Just keep in mind that if your Operator SOPs do require to insert the routing to the alternate then you'd better be in the position of actually doing it. For example we do that, as we crosscheck the difference in the FMGC alternate fuel predictions vs OFP (Lido) for gross error checks.
When using the secondary to plan for an alternate routing, just use it as a reference for the distance to go and then use the Flysmart (or paper QRH/FCOM data if you're not no paper cockpit yet) to find official alternate fuel values. I mean, the secondary flight plan works perfectly fine, but the FMGC values are advisory in nature, hence for legality purposes you need a crosscheck with an approved piece of documentation.