Hi there,I've got a small question just out curious.When does an aicraft get it's clearence?Prior Pushback and after Installing the FMC for confirmination of there route, with sid and route clearence?Or when the crue requesting the clearence and then installing the FMC?Thanks,Ramon.

give or take a bit. 30mins before off blocks.Howard

:D ok thanksRamon

Ramon most flight plans are block booked by your company.They are set for the best costs and timeings.It could be one flight per day or twenty.These can last for all year or the charter flights for part of the year.as such the route is kept much the same and is stored in the FMC CO Routes.You have to update each flight though as for weather paxs loads atc delays and such.You get your company release via telex or a c/pit visit.When the loads sheets etc tally.They try to do that so you have a least 30mins ahead of O/B.Howard

I have no real-world experience with this, but practically speaking, when I fly on VATSIM, I request my clearance after I have entered the route into the FMC, and before I start the engines. I get the FMC fully ready to go, except I don't choose the departure runway or setup the V-speeds.Once I get my clearance, I'm usually then cleared for engine start and pushback. If I have not been given a departure runway to expect, I ask for it, since sometimes it affects the direction I turn the aircraft during pushback.Once I have the departure runway, I finish the FMC v-speed setup, and then I'm ready for taxi.