"properly designed, it doesn't slow down much in this process, and thus doesn't induce as much drag as it would if it hit the nose of the plane."
Properly designed, huh? I think you're assuming a lot. The airflow MUST slow down in the process, because it needs to be compressed in order to burn.
Look, the calculations are a bit beyond the scope of what I'm gonna post on/. (html equation editing==pita). The intake throat diameter is going to be much, much smaller than the frontal area of the hypersonic craft. eg: http://www.nasa.gov/missions/research/x43-main.html
If you can design a scramjet engine with a frontal area/thrust ratio similar to a rocket, you are going to make a very large amount of money. That is beyond the current state of the art. Consider the stoichiometry of combustion: How much O2 are you going to need to burn your fuel? Lots. How high up is this thing going to operate? High. The whole front of the aircraft is going to be a ramp which, along with the oblique bow shock wave, is going to start compressing air for combustion. You'll have another oblique shock wave system inside the engine throat, which will have to be VERY carefully managed. An engine unstart at hypersonic speeds would be a very, very, very bad thing. Unstart is what would happen if the nice supersonic airflow through the engine throat is disturbed in such a way that the oblique shock waves turn into normal shocks (perpendicular to the airflow). Air crossing a normal shock wave slows to sub-sonic speed, instantly reducing the amount of airflow through the engine and dramatically increasing drag. By "dramatically", I mean "Wow, the aircraft just disintegrated. That sucks!"
(fun fact: The difference between a ramjet and a scramjet is that normal shock wave. Ramjets have them, scramjets do not. Which is also why you need to be traveling faster than Mach 1 to light a ramjet.)
There's a reason that we don't have sustainable supersonic combustion ramjets. This stuff is really, really difficult.
Fuels that explode spontaneously when in contact with air are pretty darn dangerous to handle. There are projects to evaluate how to auto-ignite fuel, but none of this stuff is easy when you're talking about trying to get useful fuel mixing somewhere close to the aircraft in a high-speed flow.
Problem is, you have to have a large frontal area to ingest air to burn. Large frontal area is the enemy of high speed. Back-of-the-envelope calculations yield a frontal area for an air-breathing vehicle about four times greater than a rocket-powered vehicle with the same thrust. Larger frontal area=more drag (drag is approximately proportional to the square of frontal area), and more drag with the same thrust means much smaller acceleration.
And you need to accelerate a LOT to get to orbital velocity.
I've studied this at the undergraduate level, and I haven't been able to make the trade-offs work on paper. That doesn't mean that people way smarter than me haven't come up with a solution, but it's going to be a non-trivial one.
Which is great and all, except when you talk about their "networks" you're really talking about frequency space that was given to them at no cost, which they're exploiting for oligarchy profits.
Had they borne all of the costs for creating their "networks", they'd be entitled to pricing as they saw fit. Since they didn't, they aren't.
Um, in other words, the scenario described is much worse than the worst case scenario and is, therefore, equipped with a substantial safety margin. In this context, that seems pretty reasonable.
I definitely agree with your overall point. Any number of great stories start with the end conditions, and go back and show you what's what. (Memento anyone?) It's a function of being a good storyteller, not the gross arrangement of plot elements.
Right, so until they accept your changes, the new bogus contract is void. That's about perfect, innit? The old contract that had already been agreed to will still be in force, and the new ridiculous one will be void.
That's simply absurd. The republicans and democrats control the mechanism of democracy in every county in the US. Why on earth would they ever permit somebody else to win?
Damn skippy! I've already been awarded the "Heisenberg Medal for Excellence in Field Engineering", but the guys on the committee were drunk, too. I don't think that counts.
Slashdot Mirror
"properly designed, it doesn't slow down much in this process, and thus doesn't induce as much drag as it would if it hit the nose of the plane."
/. (html equation editing==pita). The intake throat diameter is going to be much, much smaller than the frontal area of the hypersonic craft. eg: http://www.nasa.gov/missions/research/x43-main.html
Properly designed, huh? I think you're assuming a lot. The airflow MUST slow down in the process, because it needs to be compressed in order to burn.
Look, the calculations are a bit beyond the scope of what I'm gonna post on
If you can design a scramjet engine with a frontal area/thrust ratio similar to a rocket, you are going to make a very large amount of money. That is beyond the current state of the art. Consider the stoichiometry of combustion: How much O2 are you going to need to burn your fuel? Lots. How high up is this thing going to operate? High. The whole front of the aircraft is going to be a ramp which, along with the oblique bow shock wave, is going to start compressing air for combustion. You'll have another oblique shock wave system inside the engine throat, which will have to be VERY carefully managed. An engine unstart at hypersonic speeds would be a very, very, very bad thing. Unstart is what would happen if the nice supersonic airflow through the engine throat is disturbed in such a way that the oblique shock waves turn into normal shocks (perpendicular to the airflow). Air crossing a normal shock wave slows to sub-sonic speed, instantly reducing the amount of airflow through the engine and dramatically increasing drag. By "dramatically", I mean "Wow, the aircraft just disintegrated. That sucks!"
(fun fact: The difference between a ramjet and a scramjet is that normal shock wave. Ramjets have them, scramjets do not. Which is also why you need to be traveling faster than Mach 1 to light a ramjet.)
There's a reason that we don't have sustainable supersonic combustion ramjets. This stuff is really, really difficult.
Fuels that explode spontaneously when in contact with air are pretty darn dangerous to handle. There are projects to evaluate how to auto-ignite fuel, but none of this stuff is easy when you're talking about trying to get useful fuel mixing somewhere close to the aircraft in a high-speed flow.
It's Dust.
Where's MY Panserbjørne?
Despite the very confusing designation, the F-117 is not a fighter in any meaningful sense.
Problem is, you have to have a large frontal area to ingest air to burn. Large frontal area is the enemy of high speed. Back-of-the-envelope calculations yield a frontal area for an air-breathing vehicle about four times greater than a rocket-powered vehicle with the same thrust. Larger frontal area=more drag (drag is approximately proportional to the square of frontal area), and more drag with the same thrust means much smaller acceleration.
And you need to accelerate a LOT to get to orbital velocity.
I've studied this at the undergraduate level, and I haven't been able to make the trade-offs work on paper. That doesn't mean that people way smarter than me haven't come up with a solution, but it's going to be a non-trivial one.
Which is great and all, except when you talk about their "networks" you're really talking about frequency space that was given to them at no cost, which they're exploiting for oligarchy profits.
Had they borne all of the costs for creating their "networks", they'd be entitled to pricing as they saw fit. Since they didn't, they aren't.
Yeah, but why would the congresscritter pay any attention to the ones that don't have any money?
"Airspeed is not based on engine thrust "
Um, what? Airspeed is not a linear function of engine thrust, but it's definitely related to engine thrust...
I have a pretty hard time believing that somebody's going to be acquiring 1000 first-issue hardbacks a year. Your estimate seems rather high.
Um, in other words, the scenario described is much worse than the worst case scenario and is, therefore, equipped with a substantial safety margin. In this context, that seems pretty reasonable.
Right, because it's logical to assume that authors won't ever write something new, but will continue to only write sequels!
I definitely agree with your overall point. Any number of great stories start with the end conditions, and go back and show you what's what. (Memento anyone?) It's a function of being a good storyteller, not the gross arrangement of plot elements.
So, yeah, more or less what you said. : )
Nobody's talking about whether or not Star Wars was a flop. Clearly, it wasn't. The prequels just weren't any good. Neither was Titanic.
Popularity is orthogonal to quality.
Kangaroo fucker. It's the worst thing a person can be.
I bought one copy of Zelda and Galaxy, and zero of Halo. Why does what anybody else did have any relevance?
So you still love Alaska, yeah?
Unless you buy an iPod Touch, which is a) cheaper and b) no contract.
Yeah, but that's, er, fraud.
Right, so until they accept your changes, the new bogus contract is void. That's about perfect, innit? The old contract that had already been agreed to will still be in force, and the new ridiculous one will be void.
Mission accomplished.
That's simply absurd. The republicans and democrats control the mechanism of democracy in every county in the US. Why on earth would they ever permit somebody else to win?
Damn skippy! I've already been awarded the "Heisenberg Medal for Excellence in Field Engineering", but the guys on the committee were drunk, too. I don't think that counts.
I did get to keep the potato gun, though...
How about repairing a potato gun electrode with a bottle cap, a leatherman, and duct tape? While drunk?
"Under Saddam's old plan of being far more prudent with oil stocks, Saddam and his cronies could become extremely wealthy in 40 or so years time"
FTFY.
Jesus, what was I thinking? That's WAY simpler than just clicking the "use IMAP" radio button!
Fit != work.
Why do you think that's a cable card adaptor? Because, it really looks like it's not.