The Undetectable Flying Object (UFO)

UFO (Unidentified Flying Object) is a common term that we use to refer to an alien's aircraft. However, there is a man-made aircraft which is supposed to be more sophisticated than an alien's plane: F117A Nighthawk. Not only is it unidentifiable but also undetectable by the enemy's radar. How can it be identified if radar can't even detect its presence?

Flat Shape
The nose of most conventional airplanes is round, while F117A's is flat. Why does the flat shape matter in the F117A's ability to avoid radar signals? Radar works by spreading signals into the air, just like when you shout into a well. The sound travelling down the well will go back up to where it started. Why? Because the sound coming from your mouth will hit the wall of the well and the wall will send it back. Just like the well, the round shape of an airplane is very effective in reflecting the radar signals. This situation surely doesn't work for the F117A. The flat shape of the F117A enables radar signals to be deflected to any angle of direction except back to radar.

Absorb'n Be Invisible
The flat shape of the F117A doesn't guarantee that it's always undetectable by the enemy's radar. When it turns at less than 70 degrees. It can be detected by radar like other conventional aircrafts. However, the F117A is equipped with RAM (Radar Absorbent Material). RAM, which can only be installed in an aircraft made of titanium like the F117A,works to absorb radar signals.

Look! It's just a Bird
When the flat shape of the F117A and RAM both work perfectly, all you can see on the radar operator's screen is a little bird flying. This decoy makes the radar operator unable to identify the object as either a plane or a bird flying over the area. Only when the F117A releases its bombs will the operator realize that it was a UFF (Undetectable Flying F117A). Well guys, don't ever shoot a little object flying high in the sky like a bird. It might be an F117A carrying lethal bombs! You'll be history!