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Recreating the math behind the first stealth aircraft

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Re: Recreating the math behind the first stealth aircraft

#31

Post by bob1029 »

quanto wrote: post #24

The whole mirror analogy for angular facets breaks down when you realize airplane is a moving object and at some point in its trajectory, one of the facets is likely to be facing the radar (maximum cross section). If I remember from my numerical analysis days, it was the ease of numerical computing that necessitated the facets. Think 3D graphics from the 90s. All polygons.

The primary design goal of the stealth mechanism is to get to the target undetected. By the time a radar signature shows up, the aircraft have ideally already dropped their bombs.

Being detected too late might as well be the same as not being detected at all in most practical scenarios.

Re: Recreating the math behind the first stealth aircraft

#32

Post by quanto »

hingler36 wrote: post #28
quanto wrote: post #24

The whole mirror analogy for angular facets breaks down when you realize airplane is a moving object and at some point in its trajectory, one of the facets is likely to be facing the radar (maximum cross section). If I remember from my numerical analysis days, it was the ease of numerical computing that necessitated the facets. Think 3D graphics from the 90s. All polygons.

My understanding is that this more of a tactical consideration than a technical one. When these planes were used in the Gulf war, they were absolutely detected by Iraqi radars; they were just detected too late to do anything about them. While these planes were approaching the radar stations, they were oriented in one relative direction so the radar waves could be scattered away from the source consistently. Source is…

Your answer shows why flat surfaces were acceptable for a bomber (with an asterisk) given the constraints.

Then, the question becomes why is the B-2 bomber (and latest stealth fighter jets) not angular like F 117.

Scientific computing has come a long way since the days of F-117. We do not need flat surfaces to scatter the beams away. Finding optimal curved surfaces that scatter the beams away is just a harder math problem.

Re: Recreating the math behind the first stealth aircraft

#33

Post by NewsaHackO »

tonyarkles wrote: post #21
fwip wrote: post #16

Earlier quoted context omitted.

The text is low quality because it is un-proofread LLM output.

Interesting thing I noticed was the word “magine” without the I at the start. Which felt quite human but… dunno

Oldest trick in the book is to put human like errors to make it look human. The thing everyone forgets is that almost everyone does simple spellcheck or has it automatically show the spelling errors so it’s improbable that such spelling errors are organic (of course, omitting, or having a word autocorrect makes more sense)

Re: Recreating the math behind the first stealth aircraft

#35

Post by wrs »

NewsaHackO wrote: post #33
tonyarkles wrote: post #21

Earlier quoted context omitted.

Interesting thing I noticed was the word “magine” without the I at the start. Which felt quite human but… dunno

Oldest trick in the book is to put human like errors to make it look human. The thing everyone forgets is that almost everyone does simple spellcheck or has it automatically show the spelling errors so it’s improbable that such spelling errors are organic (of course, omitting, or having a word autocorrect makes more sense)

You left out the hyphen in human-like, and the final period, so now we know you aren’t human. Nice try though.

Re: Recreating the math behind the first stealth aircraft

#36

Post by HNisCIS »

pmazumder wrote: post #27

I'm very surprised honestly that this has picked up as much as it has, and have been mulling over the polarized responses to it. few things I'd like to clarify: - yes, I do use claude quite a bit. I don't have much background in frontend design or do it for work (which is mostly low level perception and controls, ironically something I'm seldom able to use AI for), so it makes tasks for me way more accessible. I try,…

FWIW I quite liked it but I'm from the RF world so maybe I'm biased.

Re: Recreating the math behind the first stealth aircraft

#37

Post by ahartmetz »

ahartmetz wrote: post #29
MalbertKerman wrote: post #13

Earlier quoted context omitted.

> Why does detection scale as the 4th root of the RCS? Because the power returned to the antenna scales as the -4th power of the distance to the target, and detection depends on that power being greater than some threshold. If the fourth power (rather than the square) is surprising, think of the reflection as re-transmitting the power that arrived at the target. The incident power on the target goes as RCS/r^2, and t…

This -4th power also makes stealth very difficult. Reducing the RCS by a factor of 1000 reduces detection range by a factor of 5.75.

* of about 5.6

Re: Recreating the math behind the first stealth aircraft

#38

Post by NewsaHackO »

wrs wrote: post #35
NewsaHackO wrote: post #33

Earlier quoted context omitted.

Oldest trick in the book is to put human like errors to make it look human. The thing everyone forgets is that almost everyone does simple spellcheck or has it automatically show the spelling errors so it’s improbable that such spelling errors are organic (of course, omitting, or having a word autocorrect makes more sense)

You left out the hyphen in human-like, and the final period, so now we know you aren’t human. Nice try though.

Are those spelling errors?

Re: Recreating the math behind the first stealth aircraft

#39

Post by tonyarkles »

NewsaHackO wrote: post #33
tonyarkles wrote: post #21

Earlier quoted context omitted.

Interesting thing I noticed was the word “magine” without the I at the start. Which felt quite human but… dunno

Oldest trick in the book is to put human like errors to make it look human. The thing everyone forgets is that almost everyone does simple spellcheck or has it automatically show the spelling errors so it’s improbable that such spelling errors are organic (of course, omitting, or having a word autocorrect makes more sense)

> almost everyone does simple spellcheck or has it automatically show the spelling errors

Smiles in Emacs, where I do the majority of my writing and don't have any form of spellcheck set up.

I will say though... Claude is shockingly good at writing elisp. If I can't find a plugin that does something I want, it usually only takes a few turns to get exactly what I was looking for, and I learn a bunch of elisp along the way.

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