FMC and ATC

You're going to get much better replied than what I'm going to give you but here goes. In order to reach your destination, you have to follow the ATC instructions. The FMC is just a guidance of where you should be at which point; for instance at waypoint ABC you must be at FL180, at waypoint XYZ you must be at 5'000 feet etc... It does control speed, heading, climb/descent but it's basically a way of controlling your flight procedure; hence Flight Management Computer/Control.[/b]

Thanks for that. At least I am getting a picture of how I can approach this.Do you think the following set up procedure would work?

A/ Select my departure and arrival airport on standard FS2004 'create a flight' page.

B/ Select my departure gate and Aircraft (PMDG B737/800)

C/ Once I am set up at departure request IFR clearance delivery, runway and initial heading and altitude from ATC.

D/ Before push back, set up my FMC using the details received from ATC ( where available )

I'm still not sure how all this will fit together i.e when FS 2004 ATC give IFR clearance they generally instruct you to follow to follow the route set up in the GPRS. This may not agree with the route set up in the FMC. I don't know, maybe this is way over my head.

Well the FMC would just establish waypoints on the route....it's up to you then if you alter the altitude at which you will fly over these points.

Actually, although I have never checked, I think that if your FPL in the FMC matches the IFR plan you file in FS (same waypoints) ATC just might cooperate with you. You probably will have trouble with SID's, STAR's and altitudes though.

Does all of this really mean that if you install PMDG ( or any third party )aircraft that you should expect to forego ATC interaction? For me this is one of the best aspects of FS2004 and FSX.

well - obviously I can't specifically speak for you, but the general feeling against the more experienced simmers - as far as I can conclude from opinions expressed on the forum anyway - is that the FS9 ATC basically...sucks.
Well perhaps that's slightly strong, but it is not that advanced compared to the real thing anyway.

But indeed - I don't see any other way. You may be forced to make that decision, either follow ATC and ignore the pretty departure and arrival routes, or fly properly and ignore ATC.

OR - Program the entire SID / STAR into the flightplan that you file, but that probably won't work either, because ATC could quite well assign you a different landing runway then what you were expecting....

Sorry. FS9 just has it's flaws...

Okay, but you are approaching a busy airport ( such as Heathrow) and lined up for landing only to find FS9 has pushed an aircraft onto your runway........just in time to ruin your flight,am I correct? ❓

This is known to happen, yes...
Not often, but it does.