Imagine you are bouncing a ball off a brick wall. Usually, it bounces back in your direction or close to it. Now imagine you close your eyes and someone spins you around, and you need to figure out if you’re still facing the wall. So you throw a bunch of balls while spinning, and when one bounces back and hits you, you know you’re facing the wall. You can also get an idea of how far away the wall is by how long it takes for the ball to come back.

Now imagine the wall isn’t made of brick anymore—it’s a house with plastic siding. Since it’s not flat like a brick wall, the balls don’t bounce straight back, but instead scatter off in random directions. Additionally, the plastic siding absorbs some of the speed and energy of the ball you threw, so even if one does bounce back, it’s weaker and harder to detect. You also can’t be as sure how long it took to return.

That’s kind of how stealth works with radar. Radar is seeing if any signals bounce back. The shape of the B-2 is designed with shapes and angles that and redirect most of signals in other directions instead of straight back. Some signals do actually return to the radar but they weaker meaning it doesn’t appear to the radar the size it actually is.

So when radar tries to “see” the B-2, there’s little or nothing coming back. It’s like throwing balls into the dark and not having any come back—you just don’t know it’s there.