While other bits of a flight can be programmed into the FMC before push back, I would think the SID/STAR bits can only be done when the ground control has given instruction as to which runway to take off. On the other hand, without a STAR, VNAV is not able to plan a path of decend. So you need to pun in a tentative STAR and then change it when given the actual. Is this sequence of programming correct?Another question on SID/STAR: Do planes follow the programmed track (SID) or the ATC will actually dictate the path. If that's the case, why bother to program SID?Enlightenment please.Michael TanDownunda

Hey, My understanding is that when you are given your IFR clearence, before your push and start clearence they give you flight plan and SID clearence therfore you can program you SID before you leave the gate. If they decide to change runways it's no biggie, just swap the star over to the other runway while still using the same Base fix or whteva. The STAR can be left until you are in the air. I normally leave my start until I'm about 250NM out or so and program it for the expected runway and will change it if ATC says otherwise. Generally they accomodate my request! Hope this helps..

-----------------------[bR]Matthew Murray | Project Airbus[bR]

http://vatsim.pilotmedia.fi/statusindicato...tor=OD1&a=a.jpg

The following assumes you are flying on-line with Vatsim.You can normally have a good guess at your SID by looking at the winds at your departure airport, this should at least give you which direction you will depart. If there are multiple runways then a look at the charts for that airport should indicate which are the preferred ones and from that information you can set the likely SID.You should also be able to get runways in use from the controller's ATIS.Failing that, as Matthew said, the controller will give you the correct SID when he/she gives your clearance.You are expected to follow the SID as published, including any altitude restrictions, but ATC can vector you off the SID - usually a 'direct to..' to shorten the SID. As always ATC take precedence over the published SID.As Matthew said, leave your STAR until you are near your destination and then either look up the ATIS for your destination airport or wait for the controller to advise the STAR.You can also get a good idea of the STAR by looking at winds at destination airport and following the procedure mentioned for 'guessing' your SID.Again ATC can vector you off the STAR and this happens more often than it does for the SID, at least in my experience.HTH