From the good old days of aviation, pilots were able to navigate in challenging conditions, and ultimately find their way. That could be another aerodrome, or even a millitary target. Flying in todays world, someone can suppose its easy, but what about night flight? How is it possible to actually see where you go?
Back in the days, this was mainly accomplished by navigating with the help of the moonlight, so basically sufficient light was there to illuminate the path for the pilot.
Later on, with the advance of instruments, pilots were able to perform this task just by looking on their instruments “telling them” where to actually go, so there was no need for even moonlight. You could be travelling in the middle of the ocean, in the pitch black and still be able to tell where you go.
Different instruments tell the pilot different things. The altimeter shows the altitude, if you want to stay level, better that stay the same! Artificial Horizon has a brown and a blue part. The brown part represents the ground and the blue the sky. So the pilot knows where the airplane points at any time. Compass, our good old friend, showing where we are headed towards.
Of course terrain allways remains a threat for a flight thus in modern aircraft nowadays a terrain database will be integrated into the aircraft systems, thus, by knowing where the airplane is with the use of GPS, IRS etc, it can show terrain nearby and generate warning if the pilot comes dangerously close to that.
