Although airplanes are still a new technology for the history of humanity, they have become the most important vehicles in the military field, as well as in civil aviation. While the dominance of the air can even determine the fate of a country, of course, countries are rapidly increasing their investments in aircraft.
One of the most mysterious and scary concepts in aircraft technologies was ‘ghost planes’. So, how do these planes, which hide themselves from their enemies in the sky, actually work? What is the logic of ghost planes?
What is a “Ghost Airplane”?
Contrary to the perception we have when we hear the concept of ‘ghost’, ghost planes do not mean that these planes are invisible to the eye. The term ‘ghost’ refers to not only airplanes but also ships, tanks and other vehicles in the military, which have the ability to hide from enemy systems.
Therefore, stealth planes include warplanes that focus entirely on concealment from enemy systems, aiming to take the enemy by surprise in the air, and focus on not being targeted.
How do ghost planes stay hidden?
Some general techniques and methods used in other stealth vehicles are used to hide the ghost planes. The system that the planes really want to hide is the enemy radars. Hiding from radar systems, which have eyes and ears in the air and on the ground, allows one to enter the airspace and detect/destroy targets without even the spirit of that party.
A variety of methods are used to ensure that stealth aircraft are hidden from radars. But before moving on to the stealth methods used in airplanes, it is useful to briefly summarize how the system that is intended to be hidden works.
Let’s learn how the radar works:
Conventional radars, which can be found on the ground and in land, sea and air vehicles, send electromagnetic waves to the environment at regular intervals. The fact that these waves hit somewhere and reflect back to the receivers indicates the presence of a unit around.
The electromagnetic waves sent and returned to the receivers are analyzed by computers and the position, direction and type of the unit in the field can be determined according to the angle of return of the wave, the intensity and speed of the returning wave.
So, how do stealth planes hide from radars?
Ensuring that ghost planes are hidden from radars is basically preventing electromagnetic waves reflected from the plane from returning to the receivers. In this context, aircraft manufacturers can use different methods to deflect electromagnetic waves in different directions or to ensure that the waves are absorbed by the aircraft. Some of these methods are as follows:
Physical structure of the aircraft:
When you look at the F-16 and other ‘standard’ warplanes, you can see that the airframes do not have much pointy structures. This design, which is used in airplanes, is especially used to minimize the resistance in the air and therefore to increase maneuverability and speed.
But the situation is different for stealth planes. When you look at iconic stealth planes like the F-117, you can see much more angular, flat and irregularly positioned panels. Although the flatness of the sides and the surface in the aircraft design reduces the aerodynamic capability, it allows the electromagnetic wave from conventional radars to be reflected at different angles and to distant points from the receivers.
With this design, the radar waves that can be reflected back from the aircraft leave only a bird-like trace on the radar screens. Because the other waves coming to the plane are bounced in very different directions.
Wave absorbing materials used in the fuselage of aircraft:
The most critical concealment methods used in ghost planes appear in the materials used on the plane. Aircraft manufacturers have spent billions of dollars on research and development over the years, developing surfaces and especially paints that will enable them to hide aircraft from radar.
Dyes, which are used as the most common hiding material today, include special microscopic structures that will allow waves to be absorbed. These triangular structures, which you can see in the image above, ensure that an incoming radar wave is trapped in the structure and eventually loses its energy in a jerk. Thus, either a very weak wave or no wave remains from the reflected wave.
Reducing the thermal footprint of the aircraft:
One of the most important factors that makes an aircraft visible to radars and other systems is speed and the heat generated on the surface of the aircraft and released from the engines. Aircraft manufacturers receive support from special materials and paints to reduce the heat generated on the aircraft surface by air friction.
But when it comes to the engine, there are solutions that create some disadvantages. Ghost planes are deprived of technologies such as the ‘afterburner’ that enable the planes to reach high speeds, their engines work at much lower power. Although less heat is generated in this way, it greatly reduces its maneuverability in dodging enemy units if they are detected.
Of course, in order to reduce the heat trace in the engines, financial and comprehensive studies on new engine technologies continue.
So, is there no way to detect these planes? Of course there is:
Just like the relationship between white-black hat hackers on the internet, the same relationship exists in ghost planes. Countries are working on new technologies to detect enemy stealth planes in order not to be caught by surprise.
Some of the methods used to detect stealth planes today are as follows:
- low frequency radars,
- Electromagnetic wave receivers located in multiple locations
- Advanced systems used to detect the temperature of airplanes (After all, the temperature in airplanes can never be the same as the sky)