I’m so annoyed that i didn’t think of that first 
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Not very retro but very sexay. Notice how diligently they made all those non-staight-angled serration, only to utterly ruin it by having a skin about as smooth as my chin with all that bare rivetting and stuff. That thing may be stealthy if they put a layer of sealant on it, but on this pic, my bike is stealthier.
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Still hawt though
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It depends in what part of the spectrum you need to be stealthy. I’m not well versed in the high frequency EM-stuff, but if a skin feature is much smaller than the wavelenght of the emitter that’s going to paint you, then it isn’t really going to reflect much radar energy because the EM wave is going to diffract around it. It’s still going to be less observable than without those serrated edges (unless they screwed up really badly).
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From what I u derstand, any skin discontinuity will make it emit the absorbed radio waves. That’s why stealth aircraft are so smooth, and any discontuities they do have are carefully angled.
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Well no, it’s not that simple. When an obstacle approaches the size of the wavelength of the electromagnetic radiation, it stops behaving like particles and starts behaving like a wave. I’m not sure if you’ve ever seen optical diffraction experiments, but those are intended to highlight some of the effects that occur.
The gist is that, if you’d add the volume of all those rivets together, an object of the size of that sum would reflect much more energy back than would those rivets.
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That is one thing, another thing is that when a radio wave hits a surface, it travels along its surface until it hits a break, then the energy becomes radiation again and flies off into space on a direction that has a lot to do with the angle between the surface and the break.
Of course I may very well be regurgitating disinformation guff from the years when stealth technology was new. I have no background in physics sufficient to correlate nor interpret the primary sources / papers.
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Not an expert and the majority of my knowledge of radar physics stems from when I was trained to use a Ground Survellance Radar (RASIT 3190B).
My understanding is that low observable tech only works against a fairly narrow range of frequencies and that once you start dropping into VHF (like a lot of surveillance radars) and particularly HF (OTHR) or get up into the Ka Band then your RCS isn’t much different from a non-stealth platform of the same size.
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Yeah, once your airframe starts acting as a quarter half-wave resonator, its shape doesn’t matter so much any more. But that just tells you that something is there. You can’t do STT and guide a weapon with that frequency range because the spatial resolution is just ridiculously bad.
I’m not so sure. You can certainly design objects so that radar waves that permeate them get caught inside and dissipate into heat instead of reflecting back, but I think that’s only a small part of what happens.
The main reason that you see all those flat coplanar surfaces and weird angles on stealth jets is that they are designed not to act as diffuse reflectors. If you paint a diffuse reflector with radar energy, the reflections will go in all directions, sort of like a disco ball. That means that a fair amount of energy will go back to the emitter, regardless of his bearing.
With stealth planes, you try to shape them so all incoming energy is reflected into a discrete direction away from the emitter. So there’s only certain directions where incoming energy will actually get reflected back and you’d have to hold that direction very precisely for a radar to be able to track you, which practically never happens. In oversimplified terms, if a stealth plane turns in front of you, you only see a short blip as it turns through the direction where energy is reflected at you and then it’s gone again.
You can think of it like someone taking a piece of window glass and moving it around in front of you on a sunny day. Unless that person starts actively aiming the reflection at you, the probability of being hit is very low.
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That’s an interesting paper, thanks. Coming back full circle to the rivets though, if you look at the picture again, the rivet lines that run sideways accross the body of the plane are arranged in serrated patterns themselves, so the diffraction coming off of those won’t be in phase.
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That could be described as an impressive lightning storm 
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Or an in progress fuel emergency
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That made me chuckle 
they were not known for their fuel economy
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Eh, who cares? Gas is always going to be cheap and plentiful!
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We could always make them run on english electric
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