how does RCS work. I saw that the F22 has RCS similar to a bumblebee so how does that work. Does it mean that it is as hard as finding a bumblebee

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how does RCS work. I saw that the F22 has RCS similar to a bumblebee so how does that work. Does it mean that it is as hard as finding a bumblebee

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I take a bright flashlight and shine it at a wall. First it’s a vantage black wall and it seems like nothing happens, then it’s a standard beige wall and it’s obvious where the light is, then it’s a mirror and the bright light is almost blinding.

Then I shine it at another wall that is all mirrors. But this one changes in angles some flat at me, some angled up, some angled in all sorts of crazy shapes. Some of these will reflect a lot of light at me and some will send it flying every which way.

Reducing the radar cross section is rather similar. You use coatings, specific geometry (think the F117 or the hidden tail fins of the F22), and making sure everything is incredibly smooth. The end goal is to make it so as little of the radar wave (light in my above example) is reflected back to the radar. If you absorb it or send it somewhere else, the system doesn’t know because nothing came back, the same as the wave going into the sky and not hitting anything.

What this means is that the F-22 reflects about the same amount of signal back to radar antenna as you would expect from a perfectly reflective surface with an area the size of a bumble bee (assuming both are the same distance). This is not necessarily super tough to see, but the atmosphere is full of particles around this size, so it can be tough to discern. The main advantage of reduced effective range of radar. If the radar installations are spaced such that they overlap to detect normal aircraft, then a stealth aircraft can shrink their effective range such that they no longer overlap and leave gaps between radar installations.

A real bumblebee would actually have a RCS smaller than a bumblebee since it is not a particularly good reflector of radio waves.

Radar cross section and a lot of the headlines/infographics about it are a bit overly simplified.

It’s essentially how much energy is returned to the radar receiver.

Radar works like an invisible flashlight that can only be seen at a receiver.
It sends out electromagnetic waves, and has them bounce back to a receiver.
Going to use an analogy of a person trying to avoid a spot light.

Stealth works to counter this with radar absorbing coatings that absorb the waves and convert it to a small amount of heat instead of being returned.
The visual analogy would be like dressing in all matte black and making sure nothing shiny or reflective is on.

The other way is with unique geometry does it’s best to make sure there are as little areas pointing directly at the radar as possible. So that when beams hit they get bounced back into a useless direction.
So when the light shines a person turns to the side, or lays on the ground so that they have a smaller profile to the light, but it’s a plane so it just has different angles designed in.

Of course there’s a point where even a stealth aircraft can be detected when it’s so close that even wearing black and laying down doesn’t hide it.

The RCS statements are more about “in ideal conditions, the aircraft will bounce as much energy back to a receiver, as a bumblebee.”