How does stealth work? Why can’t we just tune radars to look for very fast ‘bumblebees’?

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I was watching a youtube video about the b2 this morning. It mentions that while it’s not completely invisible to radar, it only has a cross section about the size of a bee. It says that radars have to fine tune their displays to only show larger objects or else it would be too cluttered.

I guess my question is, why can’t they tune their displays to only show objects moving faster than ~ 300 mph?

In: Physics

15 Answers

Anonymous 0 Comments

Because there’s unavoidable background noise that the signal gets lost in. 

Imagine trying to hear bees at a great distance. Even if you perfectly trained your hearing, a bee far enough off would be impossible to distinguish from the sounds of wind, blood moving in your ears, other objects, etc. Same thing with radar.

Modern radar is often working at the limits of signal/noise ratio. Stealth doesn’t make things invisible, it just reduces the range the radar can pick it out of the noise. Same (very) general idea as painting ships have grey so they blend into the horizon.

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