How do i correctly add aircraft to microsoft flight sim?

ive come across aircraft but i just see empty holes where the guages should be when i try to fly. what am i doing wrong?
Answers:
Find a site where you can download aircraft for free, some of them dont come complete : i.e just the panneling, sounds but not gauges you have to "gauge" this for yourself it will usually tell you on the download what it has and has not. other times the gauges will be just redirected to your standard boeing or cessna etc one that you have on file: when u download it usually unzip (extract files to a location you know where to find them) desktop maybe then cut and paste into your directory usually c:\programmefileszmicro$oft flight sim/aircraft or something to that effect or just extract them right into that directory in the first place :D happy flying :D
Not sure I haven't seen that game in 8 years, are you playing it on a Commodore 64?
The very fact that you can load the aircraft proves that you have installed it correctly. There is nothing wrong with your installation.
You dont see the guages because the author of the aircraft didnt have enough time to write the code for them.
So, there is no problem.
I hav etried installing A few aircrafts too.
I have successfully installed the SAAB Draken fighter jet. But, The Opensky Air France B-747 400 crashes after 5 minutes of flight no mater what.
IF THERE IS A PROBLEM. THEN IT IS WITH THE CODE, SO DONT WORRY AND INSTALL MORE OF THEM.

Hope I helped, Happy Cruising.
In FS2004 all you have to do is unzip the file you downloaded using winzip to the aircraft folder for most but there are some that are more complicated with installing gauge files. For more info there are many tutorials out there.