Slashdot Mirror
New Jet Engine Tested
SpaceAdmiral writes "A revolutionary new jet engine has recently been tested in Australia. It is hoped that the engine, designed by UK defense firm QinetiQ and capable of Mach 7.6, will pave the way for ultra fast, intercontinental air travel. Scramjet (supersonic combustion ramjet) engines have no moving parts and take all of the oxygen they need (to burn hydrogen fuel) from the air, allowing for larger loads than rockets which must carry oxygen for fuel."
First application for Mach 7+ won't be passenger travel, but military (if not already used) where it will not only be fast, but louder than heck - after all Jet Noise is the Sound of Freedom! ;-)
Hulk SMASH Celiac Disease
This was covered earlier!
2 3/2011251
http://science.slashdot.org/article.pl?sid=06/03/
How about top speed in level flight? Or power to weight ratio? Those allow forecasting.
This is old news.
Scramjet's are a revolutionary "new" type of engine, they have just been difficult to get from the concept to pratical stage.
The biggest problem is a way to compress enough oxygen at top speeds to feed the fuel reaction without needing to carry oxygen on board (which would be a rocket).
D.O.U.O.S.V.A.V.V.M.
IIRC, Australia's Qantas Airways was until very recently the only major airline without a crash. So, either they are good at what they do, or Australia's not a popular tourist attraction.
" Scramjet (supersonic combustion ramjet) engines have no moving parts and take all of the oxygen they need (to burn hydrogen fuel) from the air, allowing for larger loads than rockets which must carry oxygen for fuel."
What??? I'll sue right now. This infringes on the name for my patented propulsion "Spamjet" (tm) system.... a revolutionary aerospace technology by which vehicles set up Hotmail accounts, and then propel themselves across the world by converting the lengthening promises of penis spams into actual thrust.
It is remarkable how similar the intended future use for scramjet technology is to that described in a Philip K Dick novel by the name of Man in the High Castle, namely passenger airliners and space travel. The extremely fast ascent, followed by a relatively brief period in the lower stratosphere, and finally another period of intense speed, this time descending towards the relevant destination. Of course, in the novel the "Rocket ships" described are probably intended as an evolution of the V1/V2 bombs used in World War 2, a technology very different from scramjets - and completely neglectful of the potentially massive chemical costs per launch far outweighing even the most ostentatious of passenger fares :) . But even so, the similarity in timeframe description and such is remarkable considering the V2 was little more than a predecessor to the SCUD missile, and that scramjet tech was unheard of at the time of writing (1962).
He wasn't the first of course, H.G. Wells predicted something resembling an atomic bomb, together with tanks during Edwardian times. It would be interesting to examine trends in developing technology, to see whether the cause and effect correlation with sci fiction predictions is beyond the aesthetic. We can already observe that many aesthetic features of say, some of Star Trek's technology, has made its way into the modern technology of today. Eg. The flip communicators -> mobile phones etc. It is a testament to the human imagination that much of the technology posited in past fiction is coming to fruition today.
Yeah, why? Can I go out and buy it somewhere? Are there any online reviews or comparison tests available for this *new* hardware?! This is clearly science, and should be categorized so.
Scramjet (supersonic combustion ramjet) engines have no moving parts and take all of the oxygen they need (to burn hydrogen fuel) from the air, allowing for larger loads than rockets which must carry oxygen for fuel.
All jet engines take the oxygen they need from the air. Only rocket engines leaving the atmosphere require an onboard source of oxygen. Even the U2, which flew at > 40,000ft got it's oxygen from the surrounding air.
And the Scramjet is a jet engine, not a rocket engine. The difference you were looking for is that scramjet engines do not require a turbine to compress the surrounding air. This allows the engine to move at a much faster speed because turbine engines have an upper speed limit before the stresses pull them apart.
Also, theoretically if the compression was high enough the scramjet could burn jet fuel (kerosene) but there is probably technical difficulties with injection (ie. avoiding hot spots and detonation).
>>
I am the director, and this is my movie
Yeah sure, too bad the first use of scramjets will be in missile weapons.
Scramjet's are a revolutionary "new" type of engine, they have just been difficult to get from the concept to pratical stage.
From what I've seen in all those documentary films showing people testing rocket engines, they were also difficult to get from the concept to the pratical stage.
New ideas bring new challenges.
"Even the U2, which flew at > 40,000ft got it's oxygen from the surrounding air."
Bono and the boys are still flyin' high, but they always never forget to breathe.
of when i read the article, it said something about requiring an initial velocity of five times the speed of sound, before the scramjet even begins to work. basically, it's useless until you force it up to working speed. oh well.
http://xkcd.com/313/
Oh joy. For a zillion dollars I'll soon be able to launch over to London in just a few hours. Oh I just can't wait! Please...
You know I realy would just like to hop over to Miami for the day from the Space Coast for a few Hamiltons. Why is that so hard? When is THAT technology going to get here? (Gee... maybe when the government gets its d*ck out of the corporate airline twat).
:T:R:A:N:S:
DARPA (Defenase Advanced Research Project Agency) testfired a scramjet missile in 2001. The US Air Force has also been working with NASA on the developement of the X-43A which already flies at mach 9+ in its test flights (http://www.nasa.gov/missions/research/x43-main.ht ml). Both the Air Force and Navy have been working to adapt the technology to their cruise missiles.
What exactly makes this engine new? Is it a whole new concept design?
Can anyone tell me why this engine is revolutionary? NASA has been testing these types of engine for some time.
i n.html%5B/url%5D
For example, the X-43 which hit mach 9.6.
[url]http://www.nasa.gov/missions/research/x43-ma
First, read the very recent /. article and discussion on this just the other day.
A colleague of mine is the trial manager for HyShot. I will post more 'insider' details when they become available.
Looking at space, radio, science and computing from a 'down-under' amateur enthusiast perspective.
Peter Macinnis journeyed to Woomera to watch the July 2002 test of the University of Queensland's HyShot scramjet. He was lucky enough to watch history being made - the test was the world's first successful scramjet launch.
http://www.abc.net.au/science/slab/hyshot/default. htm
You're not going to shoot down anything traveling 10 times the speed of sound, at least not with a missle.
I'll bet it was a smashing success
As usual one of the leading space news websites completely ignore this launch (just like the last HyShot success), concentrating intead on the Falcon 1 mishap. I strongly suggest to this parochial site that they change their domain name to www.americanonlyspaceflightnow.com
Seeing that even the links came through as visited in my browser this should be checked first, before going though the words!
If you're going to be hitting the ground at any speed greater than a few feet per second, you might as well make it Mach 7. Not like it's going to make a whole hell of a lot of difference anyway, and the crater will be a lot more impressive.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
Scramjets have been around at least in concept for a good long time. All this particular one's predecessors have had the same problem that this one has had as well, namely that the materials they're manufactured from cannot withstand both the stresses of absurdly high speed motion and the heat produced by igniting the air. They all tend to cost quite a bit and blow up in under 10 seconds. So I'd hardly call it a new revolutionary technology, but rather a rather interesting one that the MSEs haven't caught up to yet.
"My heart is in the work." - Andrew Carnegie
Five blades is plenty for me. I want to keep my skin atleast.
... the article was referring to a new version of Microsoft's Jet Engine used by Access.
More to the point, the distance between San Francisco (in California, USA) and London (in England) is about 5000 miles. That same passenger jet at mach 7 can bring its passengers from London to San Francisco in about 1 hour. The trip would be much cheaper than that offered by a subsonic plane because 1 hour is only enough time for cheap snacks like airline peanuts and Coca-Cola whereas a 14-hour flight would mean an expensive (but low-quality) dinner tray.
On the other hand, a 1-hour flight would facilitate global infidelity. An errant British businessman could fly to San Francisco, have dinner and sex with his squeeze, and then return to London within 4 hours.
Didnt NASA just do this recently?
Still cool, but id not say its 'new'.
---- Booth was a patriot ----
I'm sure you meant to say "ultrafast air *bombing*" instead of "travel." .. just a thought.
Finally they are replacing that buggy, slow database engine used in MS-Access. I applaud them in finally getting around to fixing that putrid horrid peice of crap. Kudos to decision mak......"combustion"? "hydrogen fuel"? Aaaa shit!
Table-ized A.I.
Jesus H. Christ! Slashdot is getting so bad that even the comments are dupes.
...in Soviet Russia, the scramjet crashes you!
That and your forgetting about the time differences.
My favorite quote was from an US AirForce pilot of SR-71's. he Liked the SR-71 as he could have lunch in London, and land in time to have a late breakfast with his family in Los Anglos. That was Mach 3.
All I have to say is that is some massive Jetlag one would have to deal with.
i thought once I was found, but it was only a dream.
Furthermore - a scramjet is nearly useless as the first stage of an orbital launcher, because it wants to cruise at a steady speed. An orbital launcher wants to be steadily accelerating. The weight of the rocket fuel saved is less of a penalty than the increase in mass needed for structural reinforcement and insulation. Further yet, rocket fuel is cheap in bulk, it would be nearly twenty times more expensive expensive to fill it with unleaded down at the local mini-mart, scram jet fuel is expensive, even in bulk. (And we haven't even gotten to billions of dollars needed to build the aerodynamic stage.)
Scramjets are a solution looking for a problem, not an answer to any question.
And then you get stuck in traffic, customs, and luggage claim for the 5 hours after your flight. We have the real-world version of Niven's "Long Shot" - a vehicle so fast that the setup/takedown time vastly exceeded it's useful travel time, so as such it was generally useless compared to a vehicle that went a tenth as fast.
So they finally came up with an engine that doesn't vaporize on contact with a concrete wall? Awesome. Take that terrorists! HAH!
You're nothing; like me.
For people not to see to it that a link to The Onion was posted would be a crime against comedy.
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
This will never be used in passenger aircraft as the g-forces caused by accelerating to mach 7 will be way too uncomfortable for 90% of passengers and just plain dangerous for some (elderly and children etc...)
On a flight from london to san francisco by the time you accelerate to mach 4 in a slow comfortable way you'll already be decelerating so its really pointless.
Why can't they accelerate it to Mach 5+ and have it go up? Why do they have to start from a huge height and drop it into the ground?
Imagine a Beowulf cluster of those! ducks
New? Jeez, these things have been around since the 80's at least - I remember learning about them in my aeronautical engineering class in high school ... Here's an interesting page on the various types of jet engines including the scramjet and a diagram of how it works. It's dated 1994, but I'm sure they were around earlier.
http://www.nas.nasa.gov/About/Education/SpaceSettl ement/Nowicki/SPBI104.HTM
Hardly. An acceleration of 0.25g, which you could barely feel, would get you from 0 to Mach 7 in about 15 minutes.
TODO: Something witty here...
It's utterly untrue to say that props are more efficient than jets: clearly you do not understand how jet engines operate: they always burn the exact same fuel-air mixture - so that at the correct cruising altitude, a jet uses very little fuel indeed. The vast majority of fuel is burned to achieve the cruising altitude, and next to nothing from then on.
This is why short hops of a jet are typically very expensive: a 400 mile flight costs 90% of the fuel cost of a 4000 mile flight (or thereabouts).
I distinctly remember reading a graph published in Scientific American (Sorry, no reference!) many years ago which showed efficiency of travel by means of calories expended, per kilogram, per kilometre travelled.
It was much as one might expect, except at the extreme top end of efficiency: the most efficient form of movement on the planet is a man on a racing bicycle, but he is only slightly ahead of a fully laden 747 which flies in excess of 5000 miles.
How many escape pods are there? "NONE,SIR!" You counted them? "TWICE, SIR!"
Well, I hate to spoil the party, but we already have the technology for Mach 3+ flight (since, say, 1960: http://en.wikipedia.org/wiki/SR-71_Blackbird and it's not like we've solved the problems with creating cost-efficient passenger versions of that yet.....
r ound" trip appeals it a loooooong way off.
I wouldn't be reserving those tickets for Mach 7 too soon, considering how much harder that's gonna be. Unless the return "go-one-mile-straight-up-and-then-slam-into-the-g
Super fast maglevs will be first - betchya!
'This writing business. Pencils and what-not. Over-rated if you ask me. Silly stuff. Nothing in it' - Eeyore
I'm guessing that these things have engines that burn quite cleanly, but does anyone have a good handle on the environmental impact of zorching around at more than Mach 7?
mod parent up.
Even on relatively short international flights (new Zealand to Australia for instance), with the two hour checkin, the 30 minute luggage claim at the other end, you get very quickly into a position where almost more travel time is in the terminal rather than in the air.
"And we have seen and do testify that the Father sent the Son to be the Savior of the World" 1 John 4:14
Well, as much sense as any ridiculous method you can think of to keep the super-rich on their meeting schedule...
How many escape pods are there? "NONE,SIR!" You counted them? "TWICE, SIR!"
Assuming that you accelerate and decelerate at the same rate you can keep accelerating all the way to the half-way point between departure and destination right?
SF to London ~= 8000km
So you have 4000km to accelerate in right?
dV = sqrt(2*a*d) (assuming constant acceleration...)
Given an acceleration of 0.25G which I'm sure is not more than anyone could take, given that they are exposed to 1G their entire lives, and given that the aircraft starts stationary:
dV = sqrt(2 * a * d)
= sqrt(2 * (0.25 * 9.81) * 4e6)
= 4.43e3 m/s
= mach 13.4
By my calcs it would only take 1000km accelerating at this rate to get to mach 7. So you could cruise for the next 6000km at mach 7, then slow down for landing in the last 1000km.
(Someone check my calcs and make sure I'm not full of shit...)
my sig could kick your sig's arse...
For those homeland security freaks, this is also much safer, since it doesn't have enough oxygen in the system below mach five for the oxidation of the fuel, it would seem it wouldn't have as explosive results from getting into an accident as actually supplying an oxidizer with the fuel.
This is of course personal speculation...
I wouldn't consider the mad hatter mad. Just reality impaired. He sure can make a mean cup of tea.
Is anyone working on quiet jet (or other fast) engines? If we want "flyign sportscars", their quiet features are more important than any other except safety. Who wants to get caught up in the "sidestream noise pollution" wars of the mid-21st Century?
--
make install -not war
since it doesn't have enough oxygen in the system below mach five for the oxidation of the fuel
This has always bothered me: If the jet must already be traveling at high speed to operate, then how does it get up to high speed in the first place?
Any sufficiently well-organized community is indistinguishable from Government.
I wonder what a fleet of exo-atmospheric scrajets transports would do to the atmosphere. Do we have any idea about the potential impact to 'GAIA'?
I think it's similar to how a plane needs to be going a certain speed for there to be enough lift to get it off the ground. So they give them wheels and allow them to drive up to a minimum for takeoff. The only difference is you'd be using a second jet engine for sub-mach 5.
If you ever look into how a nozzle on a rocket engine works, you'll see a similar pattern. The gas before the nozzle can only move sub sonic. Inside the nozzle, it is compressed until it actually reaches the sound barrier. The pressures are balanced in such a way that once it breaches the center of the nozzle, the air is still moving at the speed of sound. Since a supersonic gas behaves differently than a subsonic gas, the re-expansion of the gas further accelerates it.
There is no benefit to using the jet engine that they've designed if you're only going below mach 5. But once you're that fast, you've got a means of achieving incredible velocities with less fuel on board than you would need otherwise. A ramjet is a great concept because it literally scoops the fuel from the environment.
I wouldn't consider the mad hatter mad. Just reality impaired. He sure can make a mean cup of tea.
in concocting goofy company names.
QinetiQ sounds like the fusion of Qbert and Compaq. They ought to move out to Silicon Valley, so they can rub shoulders with the guys from qoop. Or perhaps New York would be better, given that pando makes their home there.
Read the EFF's Fair Use FAQ
Maybe some experts here (about sc/ramjets) can answer a question that has always nagged me:
If the ramjet has no moving parts, and the diagrams of its cross-section always make it look like a fairly symmetrical constriction, why does the exhaust propel the thing forward? I.e. why doesn't the ignited fuel and hot air expand equally from both ends of the thing, and cause it to go nowhere?
Is it the asymmetry because of the direction of the ram air stream? Or is it because the fuel is lighted just aft of the constriction?
thanks...
Why do you insist on posting when you obviously know nothing! A normal plane takeoff goes from 0 to 100 mph in less than 10 seconds. Maintaining that same acceleration the "g force" you are taling about would get you to mach 7 (5,327 mph)less than 10min.
Instead of getting people to consume more (faster) travel and burning up the ever decreasing oxygene of the atmosphere in the process, maybe the emphasis should be directed more on things like *reducing* the need for air travel? Just like instead of encouraging road travel, the opposite should be happening. Global warming, remember? Overly dependence on foreign oil etc?
Besides, when there were problems with making the Concorde profitable that flew at a mere mach 2, how in the hell is it going to be possible to create an aircraft that would be stable enough on ground level to take off and land, and still be profitable? The quantum leaps the material science has to make to meet such needs are huge.
First off, there's a description and history on the wiki scramjet page and here's a description of scramjet operation.
IANARS (I Am Not A Rocket Scientist), but as I understand it, one of the problems in making a working scramjet is How do you go fast enough to compress the air enough to get it to warm up enough to reach combustion temperature?
Questions:
I am NOT suggesting this would solve the entire problem, and I can't be the first to consider this, but it *seems* this would allow combustion to occur at a lower air speed. What am I missing?
PS: The amount of heating of the air and/or fuel could be variable, too, so as to allow it to be used over a range of speeds.
(Warning, very handwaving explanation which most likely has technical inaccuracies but paints a basic picture.)
Basically, a ramjet relies on the inertia of an existing flow of air into its inlet to provide compression. That air continues to move to the back of the engine, and usually after the combustion chamber there is an expansion nozzle which allows the heated exhaust air to essentially push the engine forward with more force than it is resisting the incoming airflow.
As a result, for proper operation, a ramjet MUST have a source of airflow into the engine's inlet. This can be moving air into a stationary engine (practically, this means wind tunnel tests and no other situations), or forward inertia of the engine itself moving through stationary air. This is why unlike turbine-based jet engines, ramjets and scramjets have a minimum airspeed at which they will operate.
retrorocket.o not found, launch anyway?
Um, so on relatively long international flights (you know, like ones that go across big oceans), the time spent in the terminal is not as great as the time you spend in the air?
Like, I dunno, NY to Paris, or LA to Tokyo? Flights that take 12-18 hours? Am I ringing any bells here?
Yes, we're spending longer than ever in terminals, but I've got more faith in engineers making fast jets than in bureaucrats making meaningful and efficient security processes.
Why yes, I AM a rocket scientist!
That's a remarkably dumb comment.
Do you think there's only one acceleration that will get you to Mach 7? What do you suppose that acceleration to be?
Why yes, I AM a rocket scientist!
Using a totally separate engine system, or a staged aircraft (a la White Knight/SpaceShip One or the Pegasus rocket system).
Why yes, I AM a rocket scientist!
I doubt that mach 7.6 jets will make it to commercial airlines. We have been able to go at super sonic speeds Mach 3+ for decades. The only supersonic jet to go commercial was a failure largley because of the issues of noise pollution at traveling super sonic speeds. Very few airports could handle the Concorde, and fewer populations wanted them to land in their backyard. They were a nuissance.
But maybe if they are fast enough, they can make up enough time by flying supersonic only over open waters. Then they could drop to subsonic over land (relegating them mostly to coastal airports most likely). Even more of a problem than supersonic flight over land will likely be economics. They will have to get prices lower than the $10,000 per seat for the Concorde.
fair call. most of my time has been on the shorter haul itnernational flights, which warped my view of travel proportions.
I'd be more keen to find more fuel efficient ways of getting transatlantic in a plane with hundreds of people than just as fast as we can. I'm not a tree hugger, but with limited resources in terms of fossil fuel, it would be a good thing if we could accept a few more hours in the plane with less fuel burned per person carried. Is our collective time really that valuable that we can't relax and enjoy a journey?
Then again, this is the same civilisation that has developed the hummer, and all manner of SUVs rather than working on efficiency on other forms of transport.
not many of us have charge out rates which would have allowed us to fly on the concorde to save the few hours in the transatlantic run for the huge price premium. Those on holiday wouldn't typically be that desperate to save a couple of hours flying when it would cost far more than taking a bit longer on a conventional jet.
"And we have seen and do testify that the Father sent the Son to be the Savior of the World" 1 John 4:14
Hope they don't waste too much money on building fleets of their new engines. Coming Soon >t secure21.htm . Anybody know what this March is btw? The calendar for March 2006 is the same as the calendar of March 1989. Tomorrow, March 27, is the anniversary of my big asteroid, the 1,000 lb. bale that fell from my truck & plastered me 4 times. Wouldn't be here today without good ol' oxygen. Put me on the road to Wellville it did. That calendar makes this the 4th month same as 1989, including 1989. Looks like I've made the 4 quadrant loop in one piece. Only one thing left to do, bring in the Fountain of Youth this year >
http://www.newpath4.com/millenialdawnpowerandligh
http://www.newpath4.com/overweightschoolvendingmac hinesobesity2006preludetorileyfountainofyouthrelea se.htm#Thedominoes_Ievidenceofoxygenshortageinoura irsupply_IIvendingmachinefarerequiresextraoxygento powertheprocessingofbodyforeignchemicalsinprocesse dsweetsfastfoods_IIIskirtingtheedgeofbrainoxygende privationresultingin_IVincreasedmentalillnessesand _Vschoolshootingschurchburningsfamilykillingsand_V IweturnuptheProzacZoloftWellbutrinmachinetocompens atedruggeduplargeAmericanssufferingbrainoxygennutr ientstarvation_thetrapwereinatrapofdominoes_someth ingmorethanvendingmachinesisindicated_afountainofy outhwouldbeaniceadditionifsuchexists_largeamerican schoolchildrenrequiremuchmoreoxygenandnutrientstha nsmallerschoolchildreninoverseasclassroomsBANGOGOT CHAsizehasgoteverythingtodowithit_nowyouknowthetru thandthetruthshallsetusfreeoffalsecomparisonsforev er
Thanks to SlashDot for providing this Forum and soapbox!
It is hoped that the engine, designed by UK defense firm QinetiQ and capable of Mach 7.6, will pave the way for ultra fast, intercontinental air travel.
.84 cruisers. Maybe some giant Aussie aerospace firm will be interested...
But it won't. You seen the price of fuel these days? Boeing hasn't done research into hypersonic travel in years; every R&D penny they've got is going into fuel-efficient mach
It's worth noting that the scramjet in TFA runs on hydrogen, which isn't a fossil fuel. Granted most hydrogen today is cracked from natural gas, and that which they cracked from water uses electricity mostly generated by burning coal, but it doesn't have to be that way. A pool of water, a fission of uranium, and POW... fossil fuel free.
If a job's not worth doing, it's not worth doing right.
Accellerate to Mach 7, fly the main part of the trip, and decellerate in six seconds. This test proves it's easy to go from Mach 7 to zero quickly.
Didn't hey reject the the ram jet when they broke the sound barrier because it wasn't safe enough. Now they are revisiting the failed idea. Hmmm... Can't blame them for trying but it hardly seems like a practical technology.
From the mock-up pictures, this scramjet isn't going to carry an awful lot of passengers.
As an Australian, I am used to having my country used as a firing range for developing other people's nuclear weaponry at cost of limb and life, but this is really taking the piss.
What say we throw this whole techmilogical bunkum in the river where we got it from and go back up the trees? Somehow I feel much safer there.
LostOut
Let me introduce you to something that is going to revolutionise the world. A glass tube that when something called electricity is applied to it it starts to glow
And here's something else for the "news".
Humans landed on the moon!
What are you talking about?
Why yes, I AM a rocket scientist!
"Is our collective time really that valuable that we can't relax and enjoy a journey?"
I've got no idea who speaks for the value of "our collective time", sometimes getting somewhere quickly is nice. Do you seriously spend time thinking about things like that?
If I want to visit Australia, and I have two weeks' vacation, I'd like to get there in a reasonably short amount of time. Two weeks on the open ocean doesn't sound like a heck of a lot of fun.
Having said that, changing an eighteen hour flight (incl. time in the terminal) into a ten hour flight (incl. time in the terminal) doesn't necessarily simplify my logistics.
Having said that, the reason we have free markets is so that people whose value assignments differ from mine can spend money to get things that aren't necessarily valuable to me. Shocking, wot?
Why yes, I AM a rocket scientist!
(As ships spend most of their time in international waters, most ships carry fuels that would be blatantly illegal in any civilized country. Acid rain in Europe, these days, is predominantly from the shipping lanes and not from industry.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
You don't need turbines to get a ramjet to sufficient speed. A ramjet will operate at 400mph - well within the limits of a propeller engine (I believe the Rolls Royce Merlin could manage over 500 in World War II). You simply fold the propellers inwards when the ramjet hits activation speeds.
You're also assuming ramjets are solely for Earth use. Let's say you want to have a flying aircraft operate on Titan. Nice, methane atmosphere. You're extremely limited in the weight you can lug over there, so the less you carry the better. In that case, you'd have an oxygen "fuel" and use your scramjet to pull in the methane. An electrical engine would be an alternative, but you'd have trouble keeping it hot enough to function. A glider would also be good, but you've no thermals of significance.
Back on Earth, a scramjet would be valuable in the event of an emergency. There's an island off the African coast, I believe, which - when (not if) it falls into the ocean, will create a tsunami capable of wiping out the entire eastern seaboard of the Americas for several hundred miles. There simply isn't any combination of aircraft, mass transit or shipping currently in existence capable of getting more than a small percent of people to safety.
The west coast is in as much danger from faultlines, volcanoes and other disaster-causing events, but it probably isn't going to be in danger at the same time.
Thus, a simple mechanism for ferrying massive numbers of people very rapidly from coast to coast would likely eliminate most of the potential for fatalities. True, this does mean that supersonic and hypersonic aircraft will need to fly over populated areas. Oh wah. The RAF do low-level supersonic flights in populated areas all the time. Hasn't killed me ye...ughhhh..
(Seriously, I'd rather have to worry about not getting much sleep during a disaster, if on an evacuation flightpath, than getting permanent sleep if living within a hundred miles of a coastline.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Jet Lag is only a problem if you are trying to adjust to a new time of day, if you can circle the globe in one day you can do your dinner and sex and then get home and make excuses for not being hungry to your wife.
Jetlag no problemo, appatite might be?
"It is remarkable how similar the intended future use for scramjet technology is to that described in a Philip K Dick novel by the name of Man in the High Castle, namely passenger airliners and space travel."
.. H.G. Wells predicted something resembling an atomic bomb..."
No it's not. That book was 1963, and engineers like Barnes Wallis had been working on hypersonic scramjet aircraft for 15 years before then. This is 50s technology. See Nonweiler ( http://www.gbnet.net/orgs/staar/wavehist.html ).
"....V1/V2 bombs used in World War 2, a technology very different from scramjets"
V1 and V2 technologies are very different from each other. However, V1 ramjets are very SIMILAR to scramjets - they are essentially the same thing!
"..V2 was little more than a predecessor to the SCUD missile.."
This is getting silly. The V2 was a hugely influential technogical leap. All current military and commercial rockets are derived from it.
"...that scramjet tech was unheard of at the time of writing (1962)."
Ramjet technology is early 1900s (first patent I found 1913). Supersonic and hypersonic theory work was well advanced by 1950. The US Navy had a funded practical project (SCRAM) in 1961 to make a scramjet-powered missile. It was the 'current technology of the time' in the early 60s. Learn some history.
"
HG Wells predicted something CALLED the atomic bomb (The World Set Free - 1914). It matched current known technology - Wells' atomic bomb produced small amounts of energy, but continuously. Of course, Wells invented Science Fiction single-handed, and here he was taking his plots from the latest known technology.
Writers like Phillip Dick are small fry compared to Wells, and do not have the imaginative leaps that he had. Mostly, Sci-Fi writers simply extrapolate the current technology of their time. Your choice of illustrations for your position is very poor.
You would be better off picking Wells' Invisible Man and Time Machine - two incredible leaps beyond 1890s technology. Unfortunately, they are also beyond 1990s technology, and, I suspect, 2090s technology as well.
Well if you were trying to get to Australia then it might be frustrating, but in fact two weeks on the open ocean is mighty fine. I did four weeks once and regard it as one of the best times of my entire life.
The US DOD Black Projects already have scramjets working. They have been flying a spy plane called the Aurora for nearly a decade now.
Interesting that this article is considered belonging in the hardware section, and not the science section.. It seems that people have some serious plans for their next computer assembly :-)
15 minutes of acceleration is fine, but 15 minutes(!) of deceleration will make most people puke!
The announcement of the test rocked. But I ain't seen no reports AFTER the fact. Not a peep! Not even on QinetiQ's own website. So it's probably "back to the drawing board" for those enthusiasts... But what for? Certainly not for people transit. The time required for safe acceleration and deceleration would negate the benefits of a Mach 10 top speed completely!
Mach 7 isn't any easier downhill than level. You're not understanding your physics, dude! Terminal velocity, isn't anywhere near mach anything. Yes,
there is a maximum velocity that any falling object will reach in the
Earth's atmosphere. Subtracting the terminal velocity of the scramjet doesn't
do affect the mach 7 speed very much. The things that need to be worried about are the heat and stress levels on any aircraft with a scramjet. Better have a really good airconditioner for the cockpit, and maybe a transparent aluminum (aka white sapphire) or diamond windshield.
http://www10.mcadcafe.com/nbc/articles/view_articl e.php?articleid=214725
http://en.wikipedia.org/wiki/Boeing_X-43
HyFly is a hypersonics demonstration program.
The X-43, I might add, is the current record holder.
7,000 mph (11,200 km/h), or Mach 9.8, on November 16, 2004.
This space for rent.
If I had the experience and equipment to sail myself, sure. Packed into an ocean liner, not so much.
Why yes, I AM a rocket scientist!
The FAA already says that for any distance under 500 miles, driving is faster because of the commute/airport boarding/airport deplaning slowness and that's with aircraft doing 550 mph. Mach 7 speeds up air travel like not washing your hands speeds up going to the bathroom.
Nostalgia's not what it used to be.
Look at the description. If it has no moving parts it obviously cannot move. This means there can be no propulsion which can easily be proved by a rigid application of Newton's laws in exactly the same way as was done for that famous hoax that "bumblebees can fly". Any patent examiner would only need to look at the case history to disallow a scramjet patent.
An errant British businessman could fly to San Francisco, have dinner and sex with his squeeze, and then return to London within 4 hours.
If he and his mistress only spend 2 hours on dinner and sex part, they aren't doing it right.
same rocket, different engine
This space is intentionally staring blankly at you
Rotate the seats around at the point the deceleration begins. Then your body presses into the seat back and not into the seatbelt.
Either that, or require everyone to put on 5 point harnesses!
This post brought to you by your friendly neighborhood MBA.
it's ALWAYS revolutionary when the Brits or Aussies do something us Yanks have already done.
There exists no way of exchanging information without making judgments. --Bene Gesserit Axiom
On the other hand, a 1-hour flight would facilitate global infidelity. An errant British businessman could fly to San Francisco, have dinner and sex with his squeeze, and then return to London within 4 hours.
That's got to be some pretty good squeeze, seeing as how a ticket is likely to cost even more than the Concorde (Round-trip fare: New York-Paris: $US 8,720)!
In theory, there's no difference between theory and practice. In practice, there is.
Yes.
That would be complicated and heavy for a passenger plane, but no worries, I was just making fun of the proposition for long, very slow deceleration which is generally a bad idea for passenger transport, not specifically in air travel. In fact, airplanes usually decelerate by circling (a bit like ski-jumpers after the touchdown) or by increasing attack angle of the wing (nose up), so that vector of your inertia goes into the seat and deceleration is usualy done in several, separated by pauses, relatively abrupt phases (so that balance sensor in inner ear does not get confused).