Like others have said you must have saved the flight with the ATIS tuned in COM1.
When you first install FSX by default when you crank it up it will load the default flight and aircraft and it will have every thing running including the engines. When you press the ~ key this will open the ATC window and should gice you a couple of options each option will have a number beside
The number 1 is usually contact ATIS this will automatically switch COM 1 to the correct frequency needed by the airport you are at.
than to turn it off you press the ~ key again and press the number 2 option which should switch to the ground frequency.
I am guessing that by luck the frequency that was set on COM 1 just happens to be what the airport you are at uses for ATC.
That is a rare accident If you switch airports it should go away as each airport uses a different frequency and the odds of finding another airport with the same frequency is to high but it is likely
Most of us prefer to start up cold and dark and at the airport we usually call home base. I would take Fozzer advice and start out with the Cessna.
It is a very good first time aircraft and ideal for training. Even in the real world one would not just jump into a Jet aircraft, one has to crawl before you can walk.
This is what you need to do once you have fsx up and running and are at your starting airport with what ever aircraft you wish to use for starting.
Press shift + F1 this should shut down all of the engines unless you have changed assignments.
The ATIS is controlled by the radio COM 1 frequency some radios have a standby and a active frequency others only have active I have not used the aircraft you mentioned so I do not know what it is using for a radio. But in either case you need to change the frequency of COM 1.
What most of us do is to customize FSX to what we expect at the start. Which means changing the assignments to perform the most basic tasks.
As a example I use SHIFT B to turn on/off the battery and use SHIFT + G to turn on/off the generators.
The above is just a glimpse of what is involved. As I stated before you need to take a slow start and look through the learning center this is the best way to begin.
In the real world one has to take what is called a ground class which is where you learn what you need to know about ground operations and aircraft basics.
I know that you are just wanting to dive in and get flying I can understand that but there is so much more to get the full effect one needs to go through the steps as if he was flying the real thing. Trust me it really makes a difference when you under stand everything that you are doing.
But I know that some just want to fly if that is the case here than perhaps all you really need is just a basic lesson or two. which you can find in fsx as well.
