Why do you have to open the pneumatic crossfeed valves to de-ice the wings? Exactly what does the AC bus cross-tie switch do? And why do the engines only draw fuel from the center tank when all the fuel booster pumps are on? The key to understanding these and many other aspects of your aircraft is studying the schematic drawings for the various aircraft systems. That may sound a little bit dry, but to help you out I have included a Schematics section in the DC-9 Classic Flight Center that gives you live interactive schematic drawings.
What exactly is radio navigation? In short, radio navigation is the art of locating your position on the earth by use of radio waves. Radio waves can be used to find direction (bearing), distance (ranging) and also velocity to or from a station.
Radio navigation is the name of the game when you are flying a DC-9. Radio navigation, like all new things in life, can be difficult to understand at first. But once you have mastered it, it becomes second nature and you will have a much better mental picture of where you are, where you are going, and how to get there.
The cowboy's checklist for the DC-9 Classic, created by Thomas Thurnheer, contains the minimal steps needed to operate the DC-9 Classic. This checklist has been designed for those who like to keep the workload low while starting out flying the DC-9 Classic or for flying online.