Not true. LOX engines run hotter than peroxide engines, and run fuel-rich instead of oxidizer rich.
Not for an amateur project. This is where we are running into communications problems. An amateur project is going to use commonly available metals. You tweak the mix to run it cooler. John has expressed his distaste for custom aerospace alloys, both on his site and in private forums we both frequent.
And on the second point... yeah edging out ISP will gain you some. But in the end the elusive mass ratio will give you more. Isp isnt the be-all and end-all people make it out to be. Effective staging at the appropriate mach number will also give you a huge boost. There are so many data points, to hinge an argument solely on Isp is short-sighted.
New Dell's are still $399. Thats why the mac still has what... 5-7% market share? And they don't have to lose all their licensed windows software? why switch?
Once Macs are running on Intel chipsets prices will drop, but Macs are known for quality hardware... I'm not sure Apple will be able to match the bargain basement Dell prices.
Peroxide doesn't help you learn about LOX - they're completely different in almost every respect.
From an injector standpoint, yes. But at every station downstream - the chamber, throat and nozzle - for an engine with the same thrust and throttling capabilities the engine design is damn near identical. The laws of thermodynamics don't change because you change propellants. (the chamber temperature varies slightly and the mol wt of the propellants is slightly different, but your chambers wind up looking almost exactly the same.)
By Aug, they were up to 194.
That's what I'm referring to. Damn near 200. Add in your 20-40% scale with a throat (remember, he's doing throatless) and you are outperforming SS1.
Remember, now, that the effects of ISP don't scale linearly, but geometrically.
WRONG. Isp scales linearly. Mass ratio scales as a function of the log.
Delta-V = Mass * gravity * Isp * Ln ( Mass Ratio ).
Double you Isp, double your delta-v. Halve your mass ratio, increase your delta-V by a factor of **thirty**.
Carmack will admit he isn't a rocket scientist. He will also tell you peroxide was a great learning experiance because it gives you quick turnaround time. He was able to experiment with more configurations while working with peroxide than he can with LOX. It was a good learning experiance. They are sold on LOX now. (they only switched propellant formulations once).
Remember - they aren't chasing after a prize, they are a bunch of guys having fun and learning.
His Isp isnt that bad - he's hitting 200 with lox. That's not any worse than Rutan had. And he's working with throatless, a throated vehicle will get anywhere from 20-40% gain in performance.
Again, you can't compare Carmack to Rutan. Rutan is a business man who set out to win a prize with venture capital. Carmack is developing this with friends as a learning experiance. And he's not doing too shabby, especially after he figured out that peroxide sucks:)
People complain about music, but the funny thing is you have better selection today than you ever have. Because you know what? If you don't like the music being created in 2005, you can still get your hands on music from the 90s/80s/70s. It's not like that music is magically destroyed or something. Music accumulates, it doesn't go away...
Righto. Overall efficiency = E1 * E2. But you have to convert from AC (wall current) to DC since your device runs on DC, two conversions are necessary. At least here in the US, power is cheap so if this tech becomes cheap enough I think people will buy into it for the convenience.
... have come even remotely close to getting a ship into the air.
I'd say that view is a little extreme. Carmack has a ship that flies. Untethered. Granted it is unmanned. But it flies and it is scalable. The Canadian Arrow team isn't too far out.
As far as non-X-Prize teams are concerned, XCor has a rocket powered airplane that flies in excess of 10,000 feet routinely while they work out the kinks in their propulsion system. Their hope is to make that the main propulsion system in a suborbital craft.
Right now it is all about exposure for the alternative space community.
Starting next year there will be actual competitions (hopefully). But this year you prettymuch had XCOR (a airplane retrofitted with a rocket engine), Armadillo (vertical takeoff rocket) for functinal vehicles that flew. The rest of the companies had pieces. Wouldn't be much of a competition to be had. Next year there will be races (rocket racing league).
This message composed and transmitted on a system run with complete tripe that just happens to have more features and run much better than any commercial software available.
Low blow, -3. I'd counterargue but the posters before me have made some pretty good arguments. And while I have used both linux dev environments and visual studio (C++ development)... visual studio all the way.
The group that made the Soyuz (Energia) and the group that made ICBM's (don't know the name off the top of my head) were seperate groups. I can't vouch for the quality of Russian ICBM's, but you are right Soyuz rockets are great machines.
VC++ Express Edition is free and comes with.net. Free.
Not to mention the academic license is far from free, and restricts you to development at school on school owned hardware. I have a wife and a family, I'd rather do development at home where I can spend some time with them.
I can submit my results as a console project. I just thought I'd try and play around with an interface. It isn't worth $3000 to me to "play around with" Qt. Sorry. On the other hand, for free, I canm play around with.net or wxWidgets.
And my PDA is from Sharp, my camcorder is from Cannon, my digital camera is from somewhere else, my MP3 player from another manufacturer... I'm not locked into a vendor to use my memory card.
I'm looking into wxWidgets vs. Windows Forms at the moment for a project I'm working on at the moment. It's my thesis research.
Qt was eliminated right out - my project can't be made GPL (due to a piece of the code that is subject to export restrictions), and I can't afford the license cost for a commercial license (and the educational license was too restrictive: I could only develop on campus on a school owned computer.).
Windows Forms is looking very slick. Cross compatibility isn't a requirement, its something I would like. I havent bought into the whole.net or "managed C++" thing, my project is pure C++. I haven't investigated wxWidgets close enough yet to see if they mandate all of my code has to be GPL yet. If not I will give it a serious look. The sample code didn't look quite as clean or object oriented as Windows Forms did, however, which I do value. One cool thing about Windows Forms is that you can keep the "old" C++ code seperate from the Windows Forms program and just call the classes without converting them to "managed C++" or.net.
Slashdot Mirror
Not true. LOX engines run hotter than peroxide engines, and run fuel-rich instead of oxidizer rich.
... yeah edging out ISP will gain you some. But in the end the elusive mass ratio will give you more. Isp isnt the be-all and end-all people make it out to be. Effective staging at the appropriate mach number will also give you a huge boost. There are so many data points, to hinge an argument solely on Isp is short-sighted.
Not for an amateur project. This is where we are running into communications problems. An amateur project is going to use commonly available metals. You tweak the mix to run it cooler. John has expressed his distaste for custom aerospace alloys, both on his site and in private forums we both frequent.
And on the second point
-everphilski-
New Dell's are still $399. Thats why the mac still has what... 5-7% market share? And they don't have to lose all their licensed windows software? why switch?
Once Macs are running on Intel chipsets prices will drop, but Macs are known for quality hardware... I'm not sure Apple will be able to match the bargain basement Dell prices.
-everphilski-
Peroxide doesn't help you learn about LOX - they're completely different in almost every respect.
From an injector standpoint, yes. But at every station downstream - the chamber, throat and nozzle - for an engine with the same thrust and throttling capabilities the engine design is damn near identical. The laws of thermodynamics don't change because you change propellants. (the chamber temperature varies slightly and the mol wt of the propellants is slightly different, but your chambers wind up looking almost exactly the same.)
By Aug, they were up to 194.
That's what I'm referring to. Damn near 200. Add in your 20-40% scale with a throat (remember, he's doing throatless) and you are outperforming SS1.
Remember, now, that the effects of ISP don't scale linearly, but geometrically.
WRONG. Isp scales linearly. Mass ratio scales as a function of the log.
Delta-V = Mass * gravity * Isp * Ln ( Mass Ratio ).
Double you Isp, double your delta-v. Halve your mass ratio, increase your delta-V by a factor of **thirty**.
-everphilski-
very very slowly...
-everphilski-
Carmack will admit he isn't a rocket scientist. He will also tell you peroxide was a great learning experiance because it gives you quick turnaround time. He was able to experiment with more configurations while working with peroxide than he can with LOX. It was a good learning experiance. They are sold on LOX now. (they only switched propellant formulations once).
:)
Remember - they aren't chasing after a prize, they are a bunch of guys having fun and learning.
His Isp isnt that bad - he's hitting 200 with lox. That's not any worse than Rutan had. And he's working with throatless, a throated vehicle will get anywhere from 20-40% gain in performance.
Again, you can't compare Carmack to Rutan. Rutan is a business man who set out to win a prize with venture capital. Carmack is developing this with friends as a learning experiance. And he's not doing too shabby, especially after he figured out that peroxide sucks
-everphilski-
People complain about music, but the funny thing is you have better selection today than you ever have. Because you know what? If you don't like the music being created in 2005, you can still get your hands on music from the 90s/80s/70s. It's not like that music is magically destroyed or something. Music accumulates, it doesn't go away...
-everphilski-
... buy the new iPod Pico, just like the Nano, but with an inductive coil!!! no more pesky recharging jacks!
All your dollars are belong to Apple!
-everphilski-
Righto. Overall efficiency = E1 * E2. But you have to convert from AC (wall current) to DC since your device runs on DC, two conversions are necessary. At least here in the US, power is cheap so if this tech becomes cheap enough I think people will buy into it for the convenience.
-everphilski-
I'd say that view is a little extreme. Carmack has a ship that flies. Untethered. Granted it is unmanned. But it flies and it is scalable. The Canadian Arrow team isn't too far out.
As far as non-X-Prize teams are concerned, XCor has a rocket powered airplane that flies in excess of 10,000 feet routinely while they work out the kinks in their propulsion system. Their hope is to make that the main propulsion system in a suborbital craft.
-everphilski-
Right now it is all about exposure for the alternative space community.
Starting next year there will be actual competitions (hopefully). But this year you prettymuch had XCOR (a airplane retrofitted with a rocket engine), Armadillo (vertical takeoff rocket) for functinal vehicles that flew. The rest of the companies had pieces. Wouldn't be much of a competition to be had. Next year there will be races (rocket racing league).
-everphilski-
Here's some flight videos taken in preparation for the XPrize cup (not footage from the event, but some final runs taken the week before)
o me/News?news_id=310
http://www.armadilloaerospace.com/n.x/Armadillo/H
-everphilski-
No, Dark Matter was a first-day thing: "darkness covered the face of the deep".
Yeah, it was dark before he created light on the first day.
And you saw the need to post as an AC?
-everphilski-
"There can be only one"
Good idea, but even if you talked the distros into doing it, 10 people would fork it after each duel off, resulting in 3,000 distros.
-everphilski-
Hell, even Hawking has never shaken up the ideas of science and physics to anything near the degree Einstein has.
No, maybe not, but the real Stephen Hawking in a f*cking Quake Master
-everphilski-
I'll have to check my bible but I'm pretty sure it doesn't say "and on the eighth day God created Dark Matter"
In fact I'm pretty sure it says "In the beginning God created the heavens and the earth"
*cough*troll*cough*
-everphilski-
This message composed and transmitted on a system run with complete tripe that just happens to have more features and run much better than any commercial software available. ... visual studio all the way.
Low blow, -3. I'd counterargue but the posters before me have made some pretty good arguments. And while I have used both linux dev environments and visual studio (C++ development)
-everphilski-
Uh, it was the Orient express, started in 82 by Ronald Regan, designed to go Mach 10 from NY to Tokyo in 10 hours.
r craft/nasp.htm
http://www.globalsecurity.org/military/systems/ai
-everphilski-
The group that made the Soyuz (Energia) and the group that made ICBM's (don't know the name off the top of my head) were seperate groups. I can't vouch for the quality of Russian ICBM's, but you are right Soyuz rockets are great machines.
-everphilski-
VC++ Express Edition is free and comes with .net. Free.
.net or wxWidgets.
Not to mention the academic license is far from free, and restricts you to development at school on school owned hardware. I have a wife and a family, I'd rather do development at home where I can spend some time with them.
I can submit my results as a console project. I just thought I'd try and play around with an interface. It isn't worth $3000 to me to "play around with" Qt. Sorry. On the other hand, for free, I canm play around with
-everphilski-
Like IOdine said, no you can't.
And my PDA is from Sharp, my camcorder is from Cannon, my digital camera is from somewhere else, my MP3 player from another manufacturer... I'm not locked into a vendor to use my memory card.
-everphilski-
Because I can take the SD card out of my digital camera and put it into my MiniDV camera, my PDA, my laptop /desktop and my MP3 player.
-everphilski-
Hadn't heard about FOX, will give it a look. (website is loading r e a l l y s l o w . . . )
-everphilski-
I'm looking into wxWidgets vs. Windows Forms at the moment for a project I'm working on at the moment. It's my thesis research.
.net or "managed C++" thing, my project is pure C++. I haven't investigated wxWidgets close enough yet to see if they mandate all of my code has to be GPL yet. If not I will give it a serious look. The sample code didn't look quite as clean or object oriented as Windows Forms did, however, which I do value. One cool thing about Windows Forms is that you can keep the "old" C++ code seperate from the Windows Forms program and just call the classes without converting them to "managed C++" or .net.
Qt was eliminated right out - my project can't be made GPL (due to a piece of the code that is subject to export restrictions), and I can't afford the license cost for a commercial license (and the educational license was too restrictive: I could only develop on campus on a school owned computer.).
Windows Forms is looking very slick. Cross compatibility isn't a requirement, its something I would like. I havent bought into the whole
-everphilski-
... but as a recent graduate, can I opt-out? (what if I don't want to be mapped?)
BUUUURN!!!!
-everphilski-
API hasnt changed yet. All they did was re-org their site.
-everphilski-