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DARPA's hypersonic scramjet achieves successful flight

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Re: DARPA's hypersonic scramjet achieves successful flight

#71

Post by bobthepanda »

BobbyJo wrote: post #67
jackschultz wrote: post #2

DARPA has such a list of impressive, world wide useful technologies that wouldn't have been able to be created without funding from the government at the time given the time and money and at time, unlikeliness to be successful [0]. It really sucks that there's a 'D' for 'Defense' at the front of the acronym. Their website says they're "creating breakthrough technologies and capabilities for national security". Horrib…

Not to be a Debbie Downer, but functional Scramjet technology does very little for humanity outside of defense. As is the case with most of what DARPA funds, no? If that wasn't the case, then the market itself would be chasing the technology. Like, what would this be useful for? I guess I'm just fundamentally questioning what you mean when you say 'human progress'. I assume you mean it more in terms of improvement as…

Shrinking the world would be a good use of it if we could get it to work for commercial air travel (and if we solve the sonic boom problem, but that's another issue a different part of government is working on)

Re: DARPA's hypersonic scramjet achieves successful flight

#74

Post by merpnderp »

WhisperingShiba wrote: post #61
qaq wrote: post #21

Earlier quoted context omitted.

Well could you point to the downside of this? From teflon to internet and countless other things you use every day that came out of DARPA and other def. research, what would have changed if it was funded via different model?

One prominent one is that we use fear to control other countries instead of love. We spend so much human talent on defense, and sure we got a bunch of great technologies, but who's to say that we wouldn't have got them through some other avenue, later? Or perhaps even better technologies. I only speculate about the former, but I am quite certain a lot of the violence in the world has been caused by American Neo-colon…

How did the US fuck over Russia in WWII? And are you aware of the billions of foreign aid many countries get from the US which is tied to issues like human rights, freedom, and democracy?

Re: DARPA's hypersonic scramjet achieves successful flight

#75

Post by silexia »

bobthepanda wrote: post #71
BobbyJo wrote: post #67

Earlier quoted context omitted.

Not to be a Debbie Downer, but functional Scramjet technology does very little for humanity outside of defense. As is the case with most of what DARPA funds, no? If that wasn't the case, then the market itself would be chasing the technology. Like, what would this be useful for? I guess I'm just fundamentally questioning what you mean when you say 'human progress'. I assume you mean it more in terms of improvement as…

Shrinking the world would be a good use of it if we could get it to work for commercial air travel (and if we solve the sonic boom problem, but that's another issue a different part of government is working on)

The faster you go and the further you go, the more energy you use. We have limited resources and these technologies damage our planet.

Re: DARPA's hypersonic scramjet achieves successful flight

#76

Post by qq4 »

jackschultz wrote: post #2

DARPA has such a list of impressive, world wide useful technologies that wouldn't have been able to be created without funding from the government at the time given the time and money and at time, unlikeliness to be successful [0]. It really sucks that there's a 'D' for 'Defense' at the front of the acronym. Their website says they're "creating breakthrough technologies and capabilities for national security". Horrib…

I would argue that in order to make great progress a nation needs great security.

Re: DARPA's hypersonic scramjet achieves successful flight

#77

Post by echelon »

politician wrote: post #72

PSA: Before posting comments decrying military spending, please recall that our species now exists perpetually under threat of Mutually Assured Destruction from nuclear weapons hanging overhead. Your entire way of life is predicated on this fact.

Life has been good for so long that many people don't think about this.

Power balances, allegiances, resource distribution, and entire economies are shifting. This is the real game. It's not about which smartphone supplier sells the most units. It's about projection of power to secure trade, resources, and national interests.

The relative comfort of the post cold war era may not be perpetual. Our little Instagram dopamine bubbles divorce us from the cold, uncaring reality.

Re: DARPA's hypersonic scramjet achieves successful flight

#78

Post by jhgb »

> The HAWC vehicle operates best in oxygen-rich atmosphere, where speed and maneuverability make it difficult to detect in a timely way.

I'm reasonably sure that the infrared trace of a hypersonic vehicle doesn't make it difficult to detect. Likewise existing approaches to radar stealth are hard to reconcile with hypersonic speeds, which doesn't help avoid radar detection either.

Re: DARPA's hypersonic scramjet achieves successful flight

#79

Post by sudosysgen »

jhgb wrote: post #78

> The HAWC vehicle operates best in oxygen-rich atmosphere, where speed and maneuverability make it difficult to detect in a timely way. I'm reasonably sure that the infrared trace of a hypersonic vehicle doesn't make it difficult to detect. Likewise existing approaches to radar stealth are hard to reconcile with hypersonic speeds, which doesn't help avoid radar detection either.

Plasma stealth is an existing approach to radar stealth that is made easier by hypersonic speeds.

Infrared targeting of multiple hypersonic missiles is easier said than done. The missile you're hitting them with is going to be heating up the air around the camera probably at the same temps as the missile it's intercepting, and a base station wouldn't have enough resolution to guide a missile accurately from 100+km away while being alert for other missiles.

Re: DARPA's hypersonic scramjet achieves successful flight

#80

Post by speedybird »

pengaru wrote: post #70
sonofhans wrote: post #28

Earlier quoted context omitted.

The J58 powering the SR-71 is still one of the most complex engines ever built. The space shuttle is a simple rocket by comparison. https://en.wikipedia.org/wiki/Pratt_%26_Whitney_J58

And the SR-71 is so simple the complexity falls off a cliff at the engine, hence your inclination to only care about that in comparing the two. The space shuttle is like a reusable mobile space station, airlocks and all. Occupants of the SR-71 wore space suits the entire time, there's a lot of minimalism on display in the SR-71 which is a large part of what makes it so glorious.

You seem to be suggesting but not outright saying something that is a misconception: The SR-71 did in fact have a pressurized cockpit, which was also air conditioned as well (it had to be, because the aircraft would cook the crew otherwise.)

The SR-71 was sophisticated in other ways as well; for instance in having ejection seats. In fact the first four shuttle flights (all Columbia) had ejection seats too and guess where they got those seats from? The SR-71 of course. And on those flights with ejection seats, guess what the shuttle crew wore? They wore pressure suits, like those worn by SR-71 crew! They stopped wearing those starting with STS-5, when they removed the ejection seats. However the pressure suits (though not the ejection seats) came back after the demise of the Challenger.

What I am not saying: that the shuttle was simple.

What I am saying: That the SR-71 was more sophisticated than you've given it credit for.

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