Comments on: Is this the biggest breakthrough in propulsion since the jet engine? http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine Accelerating Intelligence Sat, 25 May 2013 10:45:52 +0000 hourly 1 http://wordpress.org/?v=3.4.1 By: jd http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-78256 jd Tue, 25 Dec 2012 04:32:35 +0000 http://www.kurzweilai.net/?p=172890#comment-78256 you people are like my family while watching a movie they stare at the tv but never see a damn thing i some times wonder why the hell they even bother to watch i will explain first the engine uses both jet and rocket technology the fuel is hydrogen in order to use atmosphere in the plane the oxygen needs to be cooled why because at mach 5 air temperature reaches 1000 degrees centigrade would melt jet engines the reason for the cooler now you need much less oxygen once you leave the atmosphere you then use on board oxygen all of this was for reducing the amount of oxygen need on board the space shuttle need that gigantic tank for you guessed it oxygen to fly from new york to Paris in atmosphere heat becomes a problem again for the shell of the ship that`s why they studied the SR 71 blackbird it did mach 5 in the atmosphere reaction engine are taking clues from that research after mach 5 you need mach 25 to leave earths gravity and reach space now you use the rocket engine with the on board oxygen we saved oxygen the main goal save weight space the only questions are weight to thrust and what will it take to get in to space my math is not that good but with a little help i could do the math i was dreaming about doing this from the time i was twenty i am 3 times that age now i was using both jet and rocket engines and know i would have weight problems without even doing the math he cut the weight problems in half just with his new type of engine now for the heat shielding it would take more work than i want to put in here but there some new breakthroughs that make that a non problem so lets recap carrying an oxidizer takes most of the weight and space in all of todays rockets without that wasted weight and space with additional help from aerodynamics your cost are reduced even more the precooler makes a ssto possible much of what you people sound good but you are talking out of your collective asses its clear you don`t understand whats going on you people are like my family while watching a movie they stare at the tv but never see a damn thing i some times wonder why the hell they even bother to watch i will explain first the engine uses both jet and rocket technology the fuel
is hydrogen in order to use atmosphere in the plane the oxygen needs to be cooled why because at mach 5 air temperature reaches 1000 degrees
centigrade would melt jet engines the reason for the cooler now you need much less oxygen once you leave the atmosphere you then use on
board oxygen all of this was for reducing the amount of oxygen need on board the space shuttle need that gigantic tank for you guessed it oxygen to fly from new york to Paris in atmosphere heat becomes a problem again
for the shell of the ship that`s why they studied the SR 71 blackbird it did mach 5 in the atmosphere reaction engine are taking clues from that research after mach 5 you need mach 25 to leave earths gravity and reach space now you use the rocket engine with the on board oxygen we saved oxygen the main goal save weight space the only questions are weight to thrust and what will it take to get in to space my math is not that good but with a little help i could do the math i was dreaming about doing this from the time i was twenty i am 3 times that age now i was using both jet and rocket engines and know i would have weight problems without even doing the math he cut the weight problems in half just with his new type of engine now for the heat shielding it would take more work than i want to put in here but there some new breakthroughs that make that a non problem so lets recap carrying an oxidizer takes most of the weight and space in all of todays rockets without that wasted weight and space with additional help from aerodynamics your cost are reduced even more the precooler makes a ssto possible much of what you people sound good but you are talking out of your collective asses its clear you don`t understand whats going on

]]> By: rich http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-65312 rich Sat, 08 Dec 2012 17:24:24 +0000 http://www.kurzweilai.net/?p=172890#comment-65312 the accountants killed concord! lets hope they dont stand in the way of this leap in technical advance too, time will tell... the accountants killed concord! lets hope they dont stand in the way of this leap in technical advance too, time will tell…

]]> By: john http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-61523 john Tue, 04 Dec 2012 09:52:33 +0000 http://www.kurzweilai.net/?p=172890#comment-61523 This may be over simplified but Reaction Engines has now talked the talk. Perhaps they should check with waverider before walking the walk. This may be over simplified but Reaction Engines has now talked the talk. Perhaps they should check with waverider before walking the walk.

]]> By: Mortran http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-60812 Mortran Mon, 03 Dec 2012 14:35:33 +0000 http://www.kurzweilai.net/?p=172890#comment-60812 If this turns out to be successful, it would be the first technological progress in aeronautics after more than 40 years of technological decline. It would not only speed up air travel, but finally get humanity back into space. If this turns out to be successful, it would be the first technological progress in aeronautics after more than 40 years of technological decline. It would not only speed up air travel, but finally get humanity back into space.

]]> By: NakedApe http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-60285 NakedApe Sun, 02 Dec 2012 23:12:14 +0000 http://www.kurzweilai.net/?p=172890#comment-60285 I thought it was the sonic boom that killed the Concorde. I can just see the Neo-Luddites coming out in droves and trying to kill this incredible innovation. But, really, has anyone addressed the sonic boom problem? My ears are hurting in anticipation. I thought it was the sonic boom that killed the Concorde. I can just see the Neo-Luddites coming out in droves and trying to kill this incredible innovation. But, really, has anyone addressed the sonic boom problem? My ears are hurting in anticipation.

]]> By: zombiefood http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-59592 zombiefood Sun, 02 Dec 2012 03:09:30 +0000 http://www.kurzweilai.net/?p=172890#comment-59592 http://www.newmantools.com/vortex.htm http://www.newmantools.com/vortex.htm

]]> By: zombiefood http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-59590 zombiefood Sun, 02 Dec 2012 03:08:40 +0000 http://www.kurzweilai.net/?p=172890#comment-59590 excuse me, compressed air in and cold and hot air out excuse me, compressed air in and cold and hot air out

]]> By: zombiefood http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-59588 zombiefood Sun, 02 Dec 2012 03:06:48 +0000 http://www.kurzweilai.net/?p=172890#comment-59588 this sounds to me like some variation of a vortex tube .it is a tee with no moving parts. hot air in through one opening and cold air out another and hot air out another. i dont know where the condensate goes on the cold side or if it is separated and leaves with the heat pipe discharge. if that is the case you would be left with cold dry air and no machinery to deal with this sounds to me like some variation of a vortex tube .it is a tee with no moving parts. hot air in through one opening and cold air out another and hot air out another. i dont know where the condensate goes on the cold side or if it is separated and leaves with the heat pipe discharge. if that is the case you would be left with cold dry air and no machinery to deal with

]]> By: Just Me http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-59401 Just Me Sat, 01 Dec 2012 21:19:28 +0000 http://www.kurzweilai.net/?p=172890#comment-59401 Sorry, I misread the original problem. I agree with the 1.4g now. Sorry, I misread the original problem. I agree with the 1.4g now.

]]> By: Just Me http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-59395 Just Me Sat, 01 Dec 2012 21:06:57 +0000 http://www.kurzweilai.net/?p=172890#comment-59395 The cycle is driving me nuts. OK, put aside frosting and other condensation problems. The air enters the intake before the compressor. It is slowed to subsonic speeds (good for the flameholders later) and since the process is essentially adiabatic (ideally isentropic), it gets hot. Very hot and hypersonic speeds. That intake process has also exerted noticeable drag on the engine in the process but because it's an adiabatic process we haven't actually lost any total energy yet. Now comes the fun part. We suck the heat out of the air, lowering it's internal energy/enthalpy and we dump that heat overboard with some excess hydrogen. OK, energy lost, but we've still paid the penalty of decelerating and compressing the air in stage one. Now we complete the Brayton cycle by running it through a combustion chamber and past a turbine to run the first stage compressor. Now we can't have added too much energy in the combustion phase or the turbine fails, but it still needs to be hotter than the 1000C inlet temp or we haven't actually produced any useful thrust. Is there an afterburner stage that avoids the turbine problem? How much energy have we lost from the intercooler? This is bugging me. The cycle is driving me nuts. OK, put aside frosting and other condensation problems. The air enters the intake before the compressor. It is slowed to subsonic speeds (good for the flameholders later) and since the process is essentially adiabatic (ideally isentropic), it gets hot. Very hot and hypersonic speeds. That intake process has also exerted noticeable drag on the engine in the process but because it’s an adiabatic process we haven’t actually lost any total energy yet. Now comes the fun part. We suck the heat out of the air, lowering it’s internal energy/enthalpy and we dump that heat overboard with some excess hydrogen. OK, energy lost, but we’ve still paid the penalty of decelerating and compressing the air in stage one. Now we complete the Brayton cycle by running it through a combustion chamber and past a turbine to run the first stage compressor. Now we can’t have added too much energy in the combustion phase or the turbine fails, but it still needs to be hotter than the 1000C inlet temp or we haven’t actually produced any useful thrust. Is there an afterburner stage that avoids the turbine problem? How much energy have we lost from the intercooler?

This is bugging me.

]]> By: Just Me http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-59388 Just Me Sat, 01 Dec 2012 20:56:44 +0000 http://www.kurzweilai.net/?p=172890#comment-59388 No, if the acceleration were completely orthogonal to gravity then the total acceleration would be sqrt(2*2 + 1*1)=sqrt(5)=2.23g. The acceleration is reduced only to the extent that the craft is climbing and the acceleration is in partial opposition to gravity. See gravity drag. No, if the acceleration were completely orthogonal to gravity then the total acceleration would be sqrt(2*2 + 1*1)=sqrt(5)=2.23g. The acceleration is reduced only to the extent that the craft is climbing and the acceleration is in partial opposition to gravity. See gravity drag.

]]> By: melajara http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-59209 melajara Sat, 01 Dec 2012 15:47:36 +0000 http://www.kurzweilai.net/?p=172890#comment-59209 Watch the video (at 1 min 40), once the main engines are out of their working zone, a conventional rocket engine at the back of Skylon can be ignited for the final additional thrust needed for orbital rendezvous (alternatively, you can use the main engines fed by liquid oxygen like in a classical rocket engine). The big novelty here is to have the engine fed by oxygen taken from outside and not embarked as fuel in its liquid form. The breakthrough is the super cooler encasing the engine whose main purpose is to have the engine take high pressured oxygen (through super cooling) as intake for the reactor. Then you have consistent high thrust without over heating and most important, without needing liquid oxygen (substantial part of the fuel payload) but just liquid hydrogen as embarked fuel. Watch the video (at 1 min 40), once the main engines are out of their working zone, a conventional rocket engine at the back of Skylon can be ignited for the final additional thrust needed for orbital rendezvous (alternatively, you can use the main engines fed by liquid oxygen like in a classical rocket engine).

The big novelty here is to have the engine fed by oxygen taken from outside and not embarked as fuel in its liquid form. The breakthrough is the super cooler encasing the engine whose main purpose is to have the engine take high pressured oxygen (through super cooling) as intake for the reactor. Then you have consistent high thrust without over heating and most important, without needing liquid oxygen (substantial part of the fuel payload) but just liquid hydrogen as embarked fuel.

]]> By: Dave H. http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-59135 Dave H. Sat, 01 Dec 2012 13:54:49 +0000 http://www.kurzweilai.net/?p=172890#comment-59135 Uh, less than 2G - the acceleration's (approximately) at 90* to gravity, so vector addition will give roughly 1.4G to the seat of the pants - a lot of lifts (elevators) put you through almost as much. Hell, one of my bikes puts me through that much! For passenger use, it wouldn't need to go into orbit, just take a ballistic trajectory leaving the atmosphere to minimize drag (and thus fuel use), think V2s and ICBMs, neither reach escape nor orbital velocity - people might have to get used to weightlessness for a significant part of the flight, though. Uh, less than 2G – the acceleration’s (approximately) at 90* to gravity, so vector addition will give roughly 1.4G to the seat of the pants – a lot of lifts (elevators) put you through almost as much. Hell, one of my bikes puts me through that much!

For passenger use, it wouldn’t need to go into orbit, just take a ballistic trajectory leaving the atmosphere to minimize drag (and thus fuel use), think V2s and ICBMs, neither reach escape nor orbital velocity – people might have to get used to weightlessness for a significant part of the flight, though.

]]> By: Jack Reeve http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58923 Jack Reeve Sat, 01 Dec 2012 08:41:13 +0000 http://www.kurzweilai.net/?p=172890#comment-58923 The entire article makes utterly zero sense to me. The entire article makes utterly zero sense to me.

]]> By: Spikosauropod http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58791 Spikosauropod Sat, 01 Dec 2012 04:50:52 +0000 http://www.kurzweilai.net/?p=172890#comment-58791 How would a thing like that return from space? Where is its heat shield? How would a thing like that return from space? Where is its heat shield?

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58752 Marcos Marin Sat, 01 Dec 2012 01:16:15 +0000 http://www.kurzweilai.net/?p=172890#comment-58752 Exactly. Exactly.

]]> By: Jim Mooney http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58738 Jim Mooney Fri, 30 Nov 2012 23:44:18 +0000 http://www.kurzweilai.net/?p=172890#comment-58738 I recall that the SR-71, which could exceed Mach 5, was nearly all fuel tank. No matter how you slice it, cutting through air at that high a mach takes a tremendous amount of fuel. Of course, if you can achieve escape velocity and get above most of the atmosphere before your fuel runs out, that's a plan. I recall that the SR-71, which could exceed Mach 5, was nearly all fuel tank. No matter how you slice it, cutting through air at that high a mach takes a tremendous amount of fuel. Of course, if you can achieve escape velocity and get above most of the atmosphere before your fuel runs out, that’s a plan.

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58737 Marcos Marin Fri, 30 Nov 2012 23:37:23 +0000 http://www.kurzweilai.net/?p=172890#comment-58737 I DO NOT, I repeat, DO NOT think it is irresponsible. The "problem" your post were SUPPOSED to address WOULD have BEEN. Were it really a problem. Sorry, I went too fast =) [you're right, I didn't feel any discomfort] I DO NOT, I repeat, DO NOT think it is irresponsible.

The “problem” your post were SUPPOSED to address WOULD have BEEN.
Were it really a problem.

Sorry, I went too fast =) [you're right, I didn't feel any discomfort]

]]> By: Daniel http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58730 Daniel Fri, 30 Nov 2012 23:07:12 +0000 http://www.kurzweilai.net/?p=172890#comment-58730 Why do you think the claim is irresponsible? This company is not the first to make that claim, and technology in general is progressing to the point where it may be feasible. For example, the X-51 has shown promise with advancing scramjet technology. Why do you think the claim is irresponsible? This company is not the first to make that claim, and technology in general is progressing to the point where it may be feasible. For example, the X-51 has shown promise with advancing scramjet technology.

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58728 Marcos Marin Fri, 30 Nov 2012 22:57:17 +0000 http://www.kurzweilai.net/?p=172890#comment-58728 Dunno! I'm still struggling to figure where they will find a 1,000⁰C Atmosphere to cool off in the first place! ^_^ hahaha Dunno! I’m still struggling to figure where they will find a 1,000⁰C Atmosphere to cool off in the first place! ^_^ hahaha

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58726 Marcos Marin Fri, 30 Nov 2012 22:55:18 +0000 http://www.kurzweilai.net/?p=172890#comment-58726 Escape velocity. Escape velocity.

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58723 Marcos Marin Fri, 30 Nov 2012 22:45:34 +0000 http://www.kurzweilai.net/?p=172890#comment-58723 Who are you talking to, Bri? Who are you talking to, Bri?

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58721 Marcos Marin Fri, 30 Nov 2012 22:39:35 +0000 http://www.kurzweilai.net/?p=172890#comment-58721 Cool, I didnt know how much G's humans would find tolerable, useful post Thomas, thanks :-) Good point, they do seem to imply mutual exclusivity there -- "OR go into orbit" -- so you may be right... but I would suppose it would save quite a bit on fuel for long distances; and since this is a hybrid of rocket fuel, it is even more expensive... so every drop counts :-D And speaking of Rocket Fuel: http://www.youtube.com/watch?v=3JpwjnMFlJI Cool, I didnt know how much G’s humans would find tolerable, useful post Thomas, thanks :-)

Good point, they do seem to imply mutual exclusivity there — “OR go into orbit” — so you may be right… but I would suppose it would save quite a bit on fuel for long distances; and since this is a hybrid of rocket fuel, it is even more expensive… so every drop counts :-D

And speaking of Rocket Fuel:
http://www.youtube.com/watch?v=3JpwjnMFlJI

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58719 Marcos Marin Fri, 30 Nov 2012 22:27:03 +0000 http://www.kurzweilai.net/?p=172890#comment-58719 Thanks andmar74! I do give some thought to it, however quickly :-)it is rarely appreciated though, which is probably a good sign;-) Thanks andmar74! I do give some thought to it, however quickly :-)it is rarely appreciated though, which is probably a good sign;-)

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58717 Marcos Marin Fri, 30 Nov 2012 22:19:57 +0000 http://www.kurzweilai.net/?p=172890#comment-58717 No problem at all. Do you really think a responsible company would make this kind of irresponsible claims? Bad marketing that would be. Do you think it is a coincidence your back of the envelope calculation got you to 3.9 hours? Quite simple. Mr. Alex stepped outside the joke, perhaps as you put it, trying to sound smart. I simply followed. I for one could not ever endeavor such a hopeless task. It is bound to failure since there is no sound capable of such heights. But, since you mention, even if perhaps it was not your goal, you do manage to sound quite smart. No problem at all. Do you really think a responsible company would make this kind of irresponsible claims? Bad marketing that would be. Do you think it is a coincidence your back of the envelope calculation got you to 3.9 hours?

Quite simple. Mr. Alex stepped outside the joke, perhaps as you put it, trying to sound smart. I simply followed.

I for one could not ever endeavor such a hopeless task. It is bound to failure since there is no sound capable of such heights. But, since you mention, even if perhaps it was not your goal, you do manage to sound quite smart.

]]> By: Justin Loew http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58715 Justin Loew Fri, 30 Nov 2012 22:14:02 +0000 http://www.kurzweilai.net/?p=172890#comment-58715 As far as I can tell from this article, there is no engine yet. They have only tested components of the engine. Talk to me when a SABRE engine is in a real plane and tested in the real atmosphere. Otherwise the press release sounds like your typical hype-building message in advance of another round of financing. As far as I can tell from this article, there is no engine yet. They have only tested components of the engine. Talk to me when a SABRE engine is in a real plane and tested in the real atmosphere. Otherwise the press release sounds like your typical hype-building message in advance of another round of financing.

]]> By: Bri http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58686 Bri Fri, 30 Nov 2012 21:10:53 +0000 http://www.kurzweilai.net/?p=172890#comment-58686 Obviously passenger comfort will be taken into account on super long distance flights, the main breakthrough is for space cargo. Capitalizing near earth activities is what is needed to jump start more ambitious lunar and Martian colonies, plus asteroid mining. If it takes six or eight hours to get to china, as opposed to four and a half, I'm sure it will still be attractive. Especially to business travelers. I can't wait to here what the savings will be in terms of space cargo. Obviously passenger comfort will be taken into account on super long distance flights, the main breakthrough is for space cargo. Capitalizing near earth activities is what is needed to jump start more ambitious lunar and Martian colonies, plus asteroid mining. If it takes six or eight hours to get to china, as opposed to four and a half, I’m sure it will still be attractive. Especially to business travelers. I can’t wait to here what the savings will be in terms of space cargo.

]]> By: Daniel http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58669 Daniel Fri, 30 Nov 2012 19:58:55 +0000 http://www.kurzweilai.net/?p=172890#comment-58669 What is the point of your comment? If you're as smart as you're trying to sound, there's no reason for your comment. Therefore, I'll assume you need some help. Here's a very basic, quick analysis: Assume a constant cruising speed of 1500 m/s (about Mach 5 at 30 km altitude). Assume your destination is on the other side of the planet approximately 20,000 km away (about half the circumference of the earth at the equator). Assume constant acceleration during take-off and landing of 1g. To get from a stop to cruising speed (and vice-versa) it will take 153 seconds - 1500 m/s div 9.806 m/s^2 - and you'll cover a total of approximately 230 km over both. That leaves 19,770 km at cruising speed, which will take about 3.66 hours. So... about 2.5 minutes speeding up, 3.66 hours cruising, and 2.5 minutes going down. You'd still be under 4 hours if you either doubled the acceleration times or increased the distance by 1,000 km. So where's the problem? What is the point of your comment? If you’re as smart as you’re trying to sound, there’s no reason for your comment. Therefore, I’ll assume you need some help.

Here’s a very basic, quick analysis:
Assume a constant cruising speed of 1500 m/s (about Mach 5 at 30 km altitude). Assume your destination is on the other side of the planet approximately 20,000 km away (about half the circumference of the earth at the equator). Assume constant acceleration during take-off and landing of 1g.

To get from a stop to cruising speed (and vice-versa) it will take 153 seconds – 1500 m/s div 9.806 m/s^2 – and you’ll cover a total of approximately 230 km over both. That leaves 19,770 km at cruising speed, which will take about 3.66 hours.

So… about 2.5 minutes speeding up, 3.66 hours cruising, and 2.5 minutes going down. You’d still be under 4 hours if you either doubled the acceleration times or increased the distance by 1,000 km.

So where’s the problem?

]]> By: Thomas Jensen http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58659 Thomas Jensen Fri, 30 Nov 2012 19:32:16 +0000 http://www.kurzweilai.net/?p=172890#comment-58659 If the craft accelerates constantly longitudinally at 1G, then it reaches Mach 5 in a little over two and a half minutes... At takeoff, the passengers will experience a net force of 2G, pushing them into their seats for a few minutes. 2G is not intolerable, but the acceleration could of course be spread over several more minutes, making it much softer. I don't think the idea is to go into orbit, when using it as a normal passenger plane, but I don't know. If the craft accelerates constantly longitudinally at 1G, then it reaches Mach 5 in a little over two and a half minutes… At takeoff, the passengers will experience a net force of 2G, pushing them into their seats for a few minutes. 2G is not intolerable, but the acceleration could of course be spread over several more minutes, making it much softer. I don’t think the idea is to go into orbit, when using it as a normal passenger plane, but I don’t know.

]]> By: andmar74 http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58658 andmar74 Fri, 30 Nov 2012 19:30:43 +0000 http://www.kurzweilai.net/?p=172890#comment-58658 Nice post :-) Nice post :-)

]]> By: GatorALLin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58654 GatorALLin Fri, 30 Nov 2012 19:10:44 +0000 http://www.kurzweilai.net/?p=172890#comment-58654 Our vision is to design, build, and experimentally demonstrate a prototype pulsed plasma jet thruster targeted for orbital maneuvering, asteroid/comet rendezvous, orbital debris cleanup and interplanetary transportation. Our company, HyperV Technologies Corp., has extensive experience designing, building, operating, and deploying extremely high performance single-shot plasma accelerators of many different shapes, sizes, and power levels. These plasma jet accelerators have been developed for applications in fusion energy and high energy density plasma physics research [www.hyperv.com]. Our vision is to design, build, and experimentally demonstrate a prototype pulsed plasma jet thruster targeted for orbital maneuvering, asteroid/comet rendezvous, orbital debris cleanup and interplanetary transportation. Our company, HyperV Technologies Corp., has extensive experience designing, building, operating, and deploying extremely high performance single-shot plasma accelerators of many different shapes, sizes, and power levels. These plasma jet accelerators have been developed for applications in fusion energy and high energy density plasma physics research [www.hyperv.com].

]]> By: GatorALLin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58652 GatorALLin Fri, 30 Nov 2012 19:09:48 +0000 http://www.kurzweilai.net/?p=172890#comment-58652 Yes, but are you personally funding Pulse power for spacecraft use? do that here... http://www.kickstarter.com/projects/2027072188/plasma-jet-electric-thrusters-for-spacecraft Yes, but are you personally funding Pulse power for spacecraft use?

do that here… http://www.kickstarter.com/projects/2027072188/plasma-jet-electric-thrusters-for-spacecraft

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58632 Marcos Marin Fri, 30 Nov 2012 18:27:53 +0000 http://www.kurzweilai.net/?p=172890#comment-58632 Of course, but show me the calculations to get around the world in 3.5 hours or your post is useless. How much is 80% of "squashing" acceleration, how much is 80% of "uncomfortable" acceleration, and most importantly, how long will you be enduring it during it? don't forget the diagonal ascent and descent (respectively) to and from orbit will also increase the distance traveled in your calculations not to mention add and subtract (non respectively) gravity itself to the resultant acceleration. I'll cut you some slack and let you ignore the effects of atmospheric drag and, sure, you can add the earth rotational speed to cut you some distance, but only AFTER you're on orbit (unless you actually consider the atmosphere). But try going the OTHER WAY (i.e. East) around the earth and see how much less comfort you'll be suffering to achieve such timings then tell us what happens when your destination is less than 12h to the east. If you want to ace this, then also add how far from that point it is not worthy anymore. We will be waiting for your pertinent conclusions. Of course, but show me the calculations to get around the world in 3.5 hours or your post is useless. How much is 80% of “squashing” acceleration, how much is 80% of “uncomfortable” acceleration, and most importantly, how long will you be enduring it during it? don’t forget the diagonal ascent and descent (respectively) to and from orbit will also increase the distance traveled in your calculations not to mention add and subtract (non respectively) gravity itself to the resultant acceleration. I’ll cut you some slack and let you ignore the effects of atmospheric drag and, sure, you can add the earth rotational speed to cut you some distance, but only AFTER you’re on orbit (unless you actually consider the atmosphere). But try going the OTHER WAY (i.e. East) around the earth and see how much less comfort you’ll be suffering to achieve such timings then tell us what happens when your destination is less than 12h to the east. If you want to ace this, then also add how far from that point it is not worthy anymore.
We will be waiting for your pertinent conclusions.

]]> By: Manitou http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58612 Manitou Fri, 30 Nov 2012 17:33:50 +0000 http://www.kurzweilai.net/?p=172890#comment-58612 Exciting stuff. With rapid cooling and no of frosting, where do all the heat and water go? Can somebody explain please? Exciting stuff.
With rapid cooling and no of frosting, where do all the heat and water go? Can somebody explain please?

]]> By: Bri http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58610 Bri Fri, 30 Nov 2012 17:28:40 +0000 http://www.kurzweilai.net/?p=172890#comment-58610 @Melagara: Google David Adair. He's got a book out called A fall from space, that cronicals the problems qt NASA. His company commercializes NASA technology. He also talks about his experiences at area 51. @Melagara: Google David Adair. He’s got a book out called A fall from space, that cronicals the problems qt NASA. His company commercializes NASA technology. He also talks about his experiences at area 51.

]]> By: umut http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58608 umut Fri, 30 Nov 2012 17:25:45 +0000 http://www.kurzweilai.net/?p=172890#comment-58608 here is what I do not understand about the demonstrated technology. This is more or less a jet engine with a cooling equipment right? It still needs fresh air coming from outside and exhaust the air back again. Then how will it accomplish high orbit jobs including putting a satellite into orbit? At this heights the air intake can not be enough to run a jet engine??? here is what I do not understand about the demonstrated technology. This is more or less a jet engine with a cooling equipment right? It still needs fresh air coming from outside and exhaust the air back again.

Then how will it accomplish high orbit jobs including putting a satellite into orbit? At this heights the air intake can not be enough to run a jet engine???

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58602 Marcos Marin Fri, 30 Nov 2012 17:02:56 +0000 http://www.kurzweilai.net/?p=172890#comment-58602 Getting off the ground is not the problem though, see Wright brothers. Siege weapons have been doing it for millennia. Problem is KEEPING it there. Getting off the ground is not the problem though, see Wright brothers. Siege weapons have been doing it for millennia. Problem is KEEPING it there.

]]> By: Bruce Wright http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58591 Bruce Wright Fri, 30 Nov 2012 16:25:17 +0000 http://www.kurzweilai.net/?p=172890#comment-58591 I think it's intended as a pun. I think it’s intended as a pun.

]]> By: Editor http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58580 Editor Fri, 30 Nov 2012 16:05:58 +0000 http://www.kurzweilai.net/?p=172890#comment-58580 Explain? Explain?

]]> By: Alex Weldon http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58579 Alex Weldon Fri, 30 Nov 2012 16:04:03 +0000 http://www.kurzweilai.net/?p=172890#comment-58579 It's acceleration that presses you into the seat, not velocity. Just because the engine is capable of enough thrust to overcome the drag at Mach 5, doesn't mean they're going to crank it up to 100% on takeoff. I'm sure they'd be capable of bringing the craft up to Mach 5 in a slower way, at accelerations no worse than the takeoff of a regular passenger jet. It’s acceleration that presses you into the seat, not velocity. Just because the engine is capable of enough thrust to overcome the drag at Mach 5, doesn’t mean they’re going to crank it up to 100% on takeoff. I’m sure they’d be capable of bringing the craft up to Mach 5 in a slower way, at accelerations no worse than the takeoff of a regular passenger jet.

]]> By: Marcos Marin http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58555 Marcos Marin Fri, 30 Nov 2012 15:11:33 +0000 http://www.kurzweilai.net/?p=172890#comment-58555 getting squashed to the seat might take its toll too... getting squashed to the seat might take its toll too…

]]> By: TinyTreePublishing http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58529 TinyTreePublishing Fri, 30 Nov 2012 14:27:57 +0000 http://www.kurzweilai.net/?p=172890#comment-58529 My wife and I travel to China about every 18 months. It takes about a day and a half total travel time and all that sitting And squirming in airplane seats really takes a toll. If we could really make the same trip in 4 hours, it would be awesome! The tickets would probably cost a lot more, but it would be worth it. My wife and I travel to China about every 18 months.
It takes about a day and a half total travel time and all that sitting
And squirming in airplane seats really takes a toll.
If we could really make the same trip in 4 hours, it would be awesome!
The tickets would probably cost a lot more, but it would be worth it.

]]> By: Shawn http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58525 Shawn Fri, 30 Nov 2012 14:23:26 +0000 http://www.kurzweilai.net/?p=172890#comment-58525 Your joking, his ideas never really got off the ground Your joking, his ideas never really got off the ground

]]> By: melajara http://www.kurzweilai.net/is-this-the-biggest-breakthrough-in-propulsion-since-the-jet-engine/comment-page-1#comment-58494 melajara Fri, 30 Nov 2012 12:37:07 +0000 http://www.kurzweilai.net/?p=172890#comment-58494 This is the first real advance in propulsion technologies for more than 50 years, great! Now, if only one company would come up with something from this former NASA engineer book's (see http://www.amazon.com/exec/obidos/ISBN=1571740279/marcelkuijstensp/), then it would be THE breakthrough! This is the first real advance in propulsion technologies for more than 50 years, great!

Now, if only one company would come up with something from this former NASA engineer book’s (see http://www.amazon.com/exec/obidos/ISBN=1571740279/marcelkuijstensp/), then it would be THE breakthrough!

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