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British Skylon Engine Passes Its Tests

Unknown Lamer posted about a year and a half ago | from the some-hope-for-humanity dept.

Space 172

An anonymous reader writes "The BBC reports that the SABRE hybrid (part air-breathing jet, part rocket) that is intended to power the Skylon single-stage-to-orbit space plane has passed its final technical demonstration test, and is now looking for money (only £250m!) to prepare for manufacturing. If this goes ahead, travel into orbit from local airports (ideally, those close to the equator) will be possible. And quite cheaply. But might it have the same legal difficulties flying from U.S. airports as the Concorde did?"

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Only £250m! (5, Interesting)

bdevoe (1811096) | about a year and a half ago | (#42119937)

I sense a Kickstarter in the offing...

Re:Only £250m! (4, Funny)

ackthpt (218170) | about a year and a half ago | (#42120519)

I sense a Kickstarter in the offing...

What's the incentive for my $25? A free ride on cuise missile?

YEEEEE HAAAAAA!!!

Re:Only £250m! (0)

Anonymous Coward | about a year and a half ago | (#42121815)

More like $100k for ride.

Re:Only £250m! (0)

Anonymous Coward | about a year and a half ago | (#42121377)

Or a space lottery.
Oddly enough, the USPTO granted a patent on space lotteries.
http://www.google.com/patents/US20040176970

Re:Only £250m! (5, Insightful)

CodeheadUK (2717911) | about a year and a half ago | (#42121585)

Nothing odd about it. The USPTO would grant a patent on the look and feel of dog eggs as trade dress if it were submitted.

A chimp flinging turds with 'Approved' printed on them would be a better and more selective system.

Re:Only £250m! (2)

NatasRevol (731260) | about a year and a half ago | (#42122109)

Can't the chimp throw lot's of unlabelled crap too? just so the submitters know it's crap.

One problem (2)

0123456 (636235) | about a year and a half ago | (#42119947)

Last I read, developing Skylon was going to cost about ten billion pounds (or maybe dollars, though it's a big number either way). So there's a big jump from having an engine to being able to fly into space from your local airport.

Re:One problem (2)

osu-neko (2604) | about a year and a half ago | (#42121295)

Last I read, developing Skylon was going to cost about ten billion pounds (or maybe dollars, though it's a big number either way). So there's a big jump from having an engine to being able to fly into space from your local airport.

But how much of that has already been spent?

Re:One problem (1)

Bearhouse (1034238) | about a year and a half ago | (#42121353)

Indeed. Even if the engine/rocket motor works as advertised, they would still need to reuse some kind of space shuttle tech to get back down. Whilst I admire (some) of the space shuttle tech, the jury is long ago in - massive expensive fail.

Re:One problem (4, Informative)

Mr.CRC (2330444) | about a year and a half ago | (#42121409)

The propulsion system is completely different. The space shuttle was designed in the 70s and used the materials and design techniques of 40 years ago. There is no comparison.

Re:One problem (2, Interesting)

Anonymous Coward | about a year and a half ago | (#42121479)

The propulsion system is completely different. The space shuttle was designed in the 70s and used the materials and design techniques of 40 years ago. There is no comparison.

^ This. Also, the original space shuttle design was completely borked by military demands to increase its size. The shuttle basically suffered major bloat and feature creep, which was largely responsible for its ineffeciency and unreliabilty.

Re:One problem (4, Informative)

Anonymous Coward | about a year and a half ago | (#42121849)

Because of the low ballistic coefficient, Skylon would be slowed at higher altitudes where the air is thinner. As a result, the skin of the vehicle would only reach 1100 Kelvin (K). In contrast, the smaller Space Shuttle is heated to 2000 K on its leading edge, and so employs an extremely heat-resistant but extremely fragile silica thermal protection system. The Skylon design need not use such a system, instead opting for using a far thinner yet durable reinforced ceramic skin

Re:One problem (1)

Anonymous Coward | about a year and a half ago | (#42122461)

The space shuttle was an unpowered glider during re-entry so needed a much bigger wingspan. Skylon being single-stage, can presumably carry extra fuel to power it during re-entry as well. With powered landing you need a smaller wingspan which means less heat shields.

P.S. give it up with the space shuttle already, it was a huge achievement in its time but no comparison to what's being developed these days.

Re:One problem (2)

HornWumpus (783565) | about a year and a half ago | (#42122821)

Wingspan will be based on (more or less) wing loading, which will be based on (more or less) landing speed.

Power gives you an option to go around. But any orbital space plane will carry plenty of energy as a glider.

The odd thing about the Skylon (5, Funny)

Anonymous Coward | about a year and a half ago | (#42120001)

Is the strobing red light on the front. Seriously, what the frak?

Re:The odd thing about the Skylon (1)

Synerg1y (2169962) | about a year and a half ago | (#42120399)

If you're a commercial airliner and see that red strobe coming, you're in for one hell of a ride.

Re:The odd thing about the Skylon (4, Funny)

Anonymous Coward | about a year and a half ago | (#42120677)

Is the strobing red light on the front. Seriously, what the frak?

It is actually a white light, but the doppler shift makes it appear red.

Re:The odd thing about the Skylon (3, Informative)

mackai (1849630) | about a year and a half ago | (#42121665)

Wrong direction. Approaching would show a blue shift. Red shift means it is already passed and going away. In practical terms, one might not be able to tell the difference.

Re:The odd thing about the Skylon (1)

Daniel Dvorkin (106857) | about a year and a half ago | (#42120711)

And the way it's always looking for Sarah Connor.

What about India? (1)

Sperbels (1008585) | about a year and a half ago | (#42120011)

Several years ago I heard that India was working on a similar engine. Never heard anything more on it, I guess it didn't work. I hope the ESA has better luck.

Re:What about the SGC? (1)

elfprince13 (1521333) | about a year and a half ago | (#42122981)

Didn't they start building these into F-302s back in 2002?

Screw US Airports (2)

some old guy (674482) | about a year and a half ago | (#42120039)

And their legal (read: environmental) difficulties.

Launch from somewhere accessible to the market via other modes, but with sane local regulations.

Problem solved.

Re:Screw US Airports (1)

h4rr4r (612664) | about a year and a half ago | (#42120105)

You will need a specially strengthened runway, so any legal trouble would be sorted out before that is built.

A normal airport would not be useful for skylon.

Re:Screw US Airports (0)

Anonymous Coward | about a year and a half ago | (#42120523)

I'd imagine that Branson's spaceport in (?)Arizona(?) will do the trick...

Re:Screw US Airports (2, Informative)

Anonymous Coward | about a year and a half ago | (#42122453)

New Mexico thank you, in the unfortunately named Jornada del Muerto basin.

http://en.wikipedia.org/wiki/Spaceport_America (wikipedia)

Re:Screw US Airports (1)

Anonymous Coward | about a year and a half ago | (#42120379)

I'd guess a significant proportion of the users of this service would be USers, mostly rich, so if you don't plan a US air(space?)port and state that it's because of the stupid legislation you will suddenly find that the stupid legislation melts away.

Re:Screw US Airports (0)

Anonymous Coward | about a year and a half ago | (#42120499)

I too find that statement very strange indeed. What do US airports have to do with this? Americans are becoming more and more closed to outsiders, they prefer their own homegrown products over foreign ones, and they've got a healthy space travel industry of their own anyways.

Most likely UK/ESA will look towards Latin American nations, or Asian countries like India to purpose-build airports. Then it's just a matter of hopping over to that airport (spaceport?) from wherever in the world and catching the flight out. Americans can stay in their country and use their own products, and the rest of us will continue to interact across our borders as usual. Win-win.

Re:Screw US Airports (2)

tibit (1762298) | about a year and a half ago | (#42121957)

Far from advising xenophobia, I'd still like to point out that US is a fucking big country. Most people in Europe, for example, have no idea what a "fucking big country" is. Even supposedly well of Germans [notalwaysright.com] . Given the scale of things, a "homegrown" product in the U.S. may be equivalent from something made elsewhere in Europe for someone from there, for example.

You mean Russia? (3, Insightful)

Roger W Moore (538166) | about a year and a half ago | (#42122663)

Far from advising xenophobia, I'd still like to point out that US is a fucking big country. Most people in Europe, for example, have no idea what a "fucking big country" is.

You mean like Russia that is actually in Europe (at least the part that fits given that it is so large it spreads over two continents), contains 10 time zones, and has a land area almost twice that of the US?

Re:You mean Russia? (0)

HornWumpus (783565) | about a year and a half ago | (#42122923)

Way to miss the point. Their are American states bigger then many European countries. Many Europeans are terrible at geography. They like to tell us to 'just build trains' without a fucking clue.

Russia is whole different issue. Calling Russia 'part of Europe' is, at best, a half-truth.

Hell Russia is more like the USA then it's like Europe. After all Russia and the USA had to save Europe from itself (and it's love of government power).

Re:Screw US Airports (2)

Spy Handler (822350) | about a year and a half ago | (#42120521)

Well you wouldn't launch from just *any* airport... you always launch eastward to gain speed from earth's rotation. And you wanna be as close to the equator as feasible, and you want lots of ocean or non-populated wasteland to the east of your launch site in case your rocket blows up. Which is why we launch from the east coast of Florida or Texas.

It would take at least a few minutes from liftoff to Mach 1, by which time the spacecraft will be over empty ocean anyways. So TFSummary about concorde noise is nonsense.

Depends (1)

Roger W Moore (538166) | about a year and a half ago | (#42122819)

Well you wouldn't launch from just *any* airport... you always launch eastward to gain speed from earth's rotation.

That depends on what the purpose of your flight is. If you want to get into orbit you are correct but if you just want a sub-orbital hop between two points on the Earth's surface it doesn't really matter and given the current lack of large passenger destinations in orbit I would guess that this is the most likely initial application.

Re:Screw US Airports (2)

Catbeller (118204) | about a year and a half ago | (#42122895)

"Well you wouldn't launch from just *any* airport... you always launch eastward to gain speed from earth's rotation. "

Actually, it takes off - and flies - like a jetliner, so orientation of the runway is not a factor. The pilot can turn the plane eastward after takeoff, and then gun the engine.

Re:Screw US Airports (3, Informative)

PPH (736903) | about a year and a half ago | (#42121317)

The US "legal troubles" were a stalling tactic* back when Boeing was trying to build their own SST. The original grass roots "ban the bang" campaign was British.

*Do you really think Congress wouldn't have lifted the landing ban had the US version made it off the drafting board?

Re:Screw US Airports (1)

jcr (53032) | about a year and a half ago | (#42122113)

Launch from somewhere accessible to the market via other modes, but with sane local regulations.

So, if I want to go SFO->HKG, I'd need to hop a flight to Mexico first?

I think that would still be a win, actually.

-jcr

Re:Screw US Airports (1)

osu-neko (2604) | about a year and a half ago | (#42122971)

Launch from somewhere accessible to the market via other modes, but with a lack of sane local regulations.

FTFY

Why is something so rare called "common" sense?

The more interesting question is, why do so many people who clearly lack it complain about the lack as if it's not their own problem?

.mil only (1)

vlm (69642) | about a year and a half ago | (#42120107)

If this goes ahead, travel into orbit from local airports (ideally, those close to the equator) will be possible. And quite cheaply.

Misdirection. Ballistic aka spacex and competitors is always going to be cheaper. This only has .mil purposes. Excellent PR work, guys!

Re:.mil only (2)

h4rr4r (612664) | about a year and a half ago | (#42120125)

Citation needed.
Why would throwing away half the craft and having to carry many tons of oxidizer, which the skylon does not need, be cheaper?

Re:.mil only (3, Interesting)

0123456 (636235) | about a year and a half ago | (#42120329)

Fuel is cheap: rocket designers dream of a future where fuel will be the primary cost of launching things into space. Developing a space plane is not, and you have to invest all that money before you even know if it will work.

SpaceX estimates for launches on a reusable Falcon are similar to the estimates for Skylon, and they can build up to it, starting with expendable versions that are proving the technology and making money. Skylon has the tricky 'give us ten billion and it will probably work' hurdle to jump over.

Re:.mil only (1)

phayes (202222) | about a year and a half ago | (#42120503)

All very good points. In addition this is NOT the time to be needing a 10 billion handout from either the UK or the EU. SpaceX is progressing incrementally to reusable staged rockets and does not need any more money than they are getting from their current workload. With the Skylon precooler only just exiting proof of concept tests & really being a barely tested hurdle, I don't see it going any further in today's economic environment.

Re:.mil only (-1)

Anonymous Coward | about a year and a half ago | (#42120937)

Only $10 billion dollars? I'll take ten [likecool.com] .

Re:.mil only (1)

Anonymous Coward | about a year and a half ago | (#42121239)

All very good points. In addition this is NOT the time to be needing a 10 billion handout from either the UK or the EU.

If you had read the article, you'd have discovered that development has been 90% privately funded so far, and Mr. Bond intends to keep the same ratio of private and public money in future. In addition, all that money is not going to be up front: there are stages of development to get through. Still, what a long, strange trip it's been since work on the HOTOL spacecraft was suspended in 1988. I have great respect for Bond's peristance, engineering skills, and fundraising in the years since then.

-Gareth

Re:.mil only (2)

khallow (566160) | about a year and a half ago | (#42120595)

Fuel is cheap: rocket designers dream of a future where fuel will be the primary cost of launching things into space.

That will only happen, if you're not throwing away a vehicle every time you launch. Else you have to add the cost of the vehicle to the launch. This is where Skylon comes in. It's a completely reusable vehicle. What it doesn't have currently is a market which justifies spending ten billion dollars or euros. You have to have a lot of launches before the development costs become a small part of overall launch costs.

Re:.mil only (2)

0123456 (636235) | about a year and a half ago | (#42120869)

That will only happen, if you're not throwing away a vehicle every time you launch.

Sure. But if Skylon meets the launch cost estimates I've seen, fuel will still be only a few percent of that cost.

As I understand it, they want to use air during launch to allow them to carry a bigger payload in an SSTO, not to save money.

Re:.mil only (1)

osu-neko (2604) | about a year and a half ago | (#42121359)

That will only happen, if you're not throwing away a vehicle every time you launch. Else you have to add the cost of the vehicle to the launch.

Right, and since disposable products are always so much more expensive than reusable ones, reusable has the cost advantage.

Oh, wait...

Re:.mil only (1)

tibit (1762298) | about a year and a half ago | (#42121995)

You might be onto something. Copenhagen Suborbitals is doing "damn simple" designs using common materials like steel. Sure they have different goals, but something disposable and cheap might be another approach.

Re:.mil only (0)

Anonymous Coward | about a year and a half ago | (#42121105)

So what world do you live in where 250 million means 10 billion?

Re:.mil only (1)

0123456 (636235) | about a year and a half ago | (#42121173)

So what world do you live in where 250 million means 10 billion?

The world where space planes don't magically appear for free once you have engines for them?

Re:.mil only (1)

UK Boz (755972) | about a year and a half ago | (#42120275)

Calling bullshit on this one without anything to back it up

Re:.mil only (2)

Cyberax (705495) | about a year and a half ago | (#42120629)

Wrong!

Rockets can't be cheap. They are not reusable (you can try to reuse certain parts, but you're going to disassemble and reassemble them in any case) and that is ALWAYS going to put a high lower limit for their price. In the best case, you'll be paying millions of dollars for person to get to a lower orbit.

Skylon spaceplanes can, in theory, lower that to perhaps several tens of thousands dollars. Definitely to the level of hundreds of thousands.

Re:.mil only (1)

osu-neko (2604) | about a year and a half ago | (#42121401)

Rockets can't be cheap. They are not reusable (you can try to reuse certain parts, but you're going to disassemble and reassemble them in any case) and that is ALWAYS going to put a high lower limit for their price.

That's a weird conjecture, given that for every other manufactured thing in existence, disposable versions have a much lower limit on their price. Making things reusable always puts a high lower limit on their price. It's a lot cheaper to make something that doesn't have to last, often so much cheaper than it's cheaper than the maintenance costs of the reusable thing, even discounting the reusable items much higher initial cost.

Re:.mil only (3, Insightful)

Cyberax (705495) | about a year and a half ago | (#42121487)

How's that going for disposable cars and airplanes?

Things are disposable _because_ they can be made very cheaply. Not the other way, generally.

Re:.mil only (1)

HornWumpus (783565) | about a year and a half ago | (#42121997)

How's the reusable condom holding up?

Geronimo! (0)

Anonymous Coward | about a year and a half ago | (#42122551)

See right here [youtube.com] .

Re:.mil only (1)

Anonymous Coward | about a year and a half ago | (#42120799)

Wrong for one basic reason: Any craft using this type of engine would be able to fly from a regular civilian airport. Expendable rockets need a special launch facility in the middle of nowhere. That is a huge difference for scaling the system: SpaceX can launch from about three locations in the world, while a hybrid jet/rocket plane would be able to launch and land anywhere including near population centers. Therefore the potential customer base for the latter would be several orders of magnitude larger and bring economies of scale with it. This of course assumes there's going to be a market for fast intercontinental passenger/parcel service, or passenger service to space.

Re:.mil only (1)

0123456 (636235) | about a year and a half ago | (#42121087)

If you're paying $200,000 for a flight into space, the cost of a flight to the nearest suitable airport is noise in comparison. I'm far from convinced there's enough of a market for $200,000 London to Sydney flights to justify it as a high-speed airliner.

No (0)

Anonymous Coward | about a year and a half ago | (#42120121)

But might it have the same legal difficulties flying from U.S. airports as the Concorde did?"

No. For orbital trips, the folks who can afford it will fly their private jets to the piss poor Equatorial country and then fly into orbit from there. They governments will have been bought and paid for and as far as the people, well no one will dare say anything. And if it doesn't work out for whatever reason, why you just move! All you need is a standard strip and those are easy to come by.

It's good to be super rich!

That's the score these days.

leaves me out (1)

frovingslosh (582462) | about a year and a half ago | (#42120177)

travel into orbit from local airports (ideally, those close to the equator) will be possible

Shucks, none of my local airports seem to be near the equator. And I don't fly since the TSA started assaulting and irritating travelers.

Re:leaves me out (1)

Jafafa Hots (580169) | about a year and a half ago | (#42120297)

Just wait until commercial space flight begins and the TSA gets authority.

No more than 3 ounces of oxygen allowed per passenger. Must be sealed in a 2 quart size Ziplock.

Re:leaves me out (1)

Jeremi (14640) | about a year and a half ago | (#42121305)

Shucks, none of my local airports seem to be near the equator. And I don't fly since the TSA started assaulting and irritating travelers.

I guess the previous poster should have written "will be possible for those who are willing to make an effort".

Re:leaves me out (1)

nitehawk214 (222219) | about a year and a half ago | (#42121987)

travel into orbit from local airports (ideally, those close to the equator) will be possible

Shucks, none of my local airports seem to be near the equator. And I don't fly since the TSA started assaulting and irritating travelers.

So take the train to orbit?

That name (2)

ThatsNotPudding (1045640) | about a year and a half ago | (#42120253)

Good show, old chaps, but change the name. Sooner or later, a Skylon will turn on you.

Re:That name (1)

Synerg1y (2169962) | about a year and a half ago | (#42120433)

rofl +1 if I had mod pts today, nice BSG reference.

Re:That name (5, Informative)

Antony T Curtis (89990) | about a year and a half ago | (#42120437)

Good show, old chaps, but change the name. Sooner or later, a Skylon will turn on you.

No worries. The UK Ministry of Defense communication satellites are already called "SkyNet".

Misleading Title (5, Informative)

trout007 (975317) | about a year and a half ago | (#42120487)

The engine doesn't exist yet. This was a test of the pre-cooler. It is a critical component and it was important.

Re:Misleading Title (1)

Anonymous Coward | about a year and a half ago | (#42120787)

It was actually the MOST important test, because the rest of the engine is based on current tech.

This was new, and absolutely required in order to make the hybrid work. Without the pre-cooler, there was no point in moving forward in developing the rest of the engine.

Now, developing the rest isn't trivial - it will take significant amounts of capital, manpower, and time - but from the physics and tech standpoint, the concept is sound.

Re:Misleading Title (4, Interesting)

HornWumpus (783565) | about a year and a half ago | (#42121615)

This test used a large tank of liquid nitrogen as a heat sink.

Replacing your oxidizer tank with a coolant gas tank isn't a huge net gain. Any heat taken out of input air has to be put into the cooling system. Which is yet to be developed. The engine has to cool both the O2 and the inert parts of the air. My gut says: net loss for simply carrying coolant vs. simply carrying O2. A heat pump to fill this roll in flight is a major engineering challenge. It would require a metric assload of energy to operate.

Also note any space plane will need cooling for leading edges of flight surfaces. SR-71 did this by using pre-cooled fuel and running the fuel through heat exchangers on the leading edges just before burning.

They short circuited a huge engineering challenge by using a liquid nitrogen boiler as a heat sink.

Re:Misleading Title (3, Insightful)

Vulch (221502) | about a year and a half ago | (#42121717)

Hmmm, let's think. A space plane fueled by liquid hydrogen. Very cold liquid hydrogen. And lots of it. I wonder what they could use to cool the incoming air?

Re:Misleading Title (1)

HornWumpus (783565) | about a year and a half ago | (#42122045)

Hint: The Air and hydrogen mix a fixed ratio. There will be much more air then Hydrogen (it's not pure O2). There will be more heat in the incoming air then the Liquid H2 can absorb.

Also note: in may (most) rocket designs the cold fuel/oxidizer is used to cool the combustion chamber. Already at a delicate balance.

Re:Misleading Title (1)

trout007 (975317) | about a year and a half ago | (#42122263)

Hydrogen has a very high specific heat and heat of vaporization. From reading the wiki it says there is more hydrogen used for cooling than is needed for combustion. But part of the engine design has a part of the air bypass the compressor as well. The hydrogen is mixed and burned with this air outside the combustion chamber to recover some of these losses.

Re:Misleading Title (1)

HornWumpus (783565) | about a year and a half ago | (#42122543)

So wiki agrees with my gut. Using extra fuel as coolant.

Air is about 21% O2. That leaves 79% inert gases being cooled. Also note: H2, having low atomic weight, should have relatively low specific heat vs most of the gasses in the atmosphere.

Re:Misleading Title (3, Informative)

tibit (1762298) | about a year and a half ago | (#42122591)

Let's see. Air at atmospheric pressure has roughly 1kJ/(kg*K) heat capacity. It doesn't matter that they ram-compress thinner air, what matters is that after the ram the air will have roughly atmospheric pressure. We can assume that just to get a ballpark figure. There's about 23% by weight of oxygen in the air. When you burn hydrogen in oxygen, you join 2 mass units of hydrogen to 16 mass units of oxygen. You end up using only 2.9% of hydrogen by weight compared to weight of air, if you want a stoichiometric burn. They supposedly [wikipedia.org] cool the air down by 1140K.

So for each kg of air, you have to remove 1.1MJ of heat, and you've only got 29 grams of hydrogen to boil off. Vaporization heat of hydrogen is 0.45kJ/mol, or 0.45kJ/1g. So the boiling hydrogen can sink about 13kJ of heat, about 1% of what you need to sink. That's a no-go. It will be a no go even if all they get after the ram is 2% of atmospheric pressure, so we can be pretty sure it's no go period.

We get 286kJ/mol for combustion of hydrogen with oxygen, so we have available about 8.3MJ of heat from burning enough hydrogen to use up oxygen from a kilogram of incoming air. That may work out. Feel free to look at the Sabre cycle [wikipedia.org] and fill in the blanks as to required flow rates and temperatures, even in an idealized fashion. It should give an idea of the project's feasibility. I'm sure real engineers have already done the legwork on all that. Just that it's not as simple as "lots of very cold liquid hydrogen".

The real thing is their proprietary and at the moment confidential frost control. They've got those long tubes, they could put acoustic waves into them, hmm.

Simple, possibly (1)

fireylord (1074571) | about a year and a half ago | (#42121965)

My understanding of this issue is that the liquid hydrogen fuel will be used to carry away the excess heat, on it's way to the engine to be burnt (obviously they're not going to be wanting to suddenly start pouring heat into a tank of superchilled liquid hydrogen).

This craft will certainly NOT fly from normal aviation facilities due to the fack that having tens of tons of cryogenic hydrogen about could turn out to be rather dangerous in a busy airport...

Re:Simple, possibly (1)

HornWumpus (783565) | about a year and a half ago | (#42122135)

As I said above. Clearly more heat in the air then heat capacity of cold liquid H2. Also liquid H2 is typically used to cool the combustion chamber.

Re:Misleading Title (1)

radtea (464814) | about a year and a half ago | (#42122253)

My gut says...

It's the 21st century, hundreds of years into the Age of Reason.

WHY for the love of everything sane does anyone think what their gut says is remotely interesting or germane to any discussion of anything?

Announcing that you've not done any numerical analysis or quantitative reasoning regarding a purely quantitative question is a really, really bad way of convincing anyone rational you have anything interesting to say.

And as other posters have pointed out, because the people who are doing this are Not Idiots(TM) they have already considered your point and are planning to do the actual cooling using the liquid hydrogen fuel.

Re:Misleading Title (1)

HornWumpus (783565) | about a year and a half ago | (#42122671)

And as others have pointed out, they will be wasting extra fuel because the air is hotter then the fuel is cold. Weather it is a net gain (carrying extra fuel/coolant and drag for air scoops vs. just tanking the Oxidizer) is not obvious. These people aren't idiots, but they aren't betting their own money ether.

Gut at an engineering level is about high level thought without running all the numbers. Particularly when you don't have all the numbers, but only a conceptual framework. For example: My gut tells me that perpetual motion is BS, I don't need to see the details. This engine is perpetual motion with heat.

Re:Misleading Title (1)

DerekLyons (302214) | about a year and a half ago | (#42121217)

It's a critical component, granted, but only one of several.

As an automobile analogy - this is like proving air flows through a spiffy new carburetor. Way cool, and very critical... but very, very far from a complete test of the carburetor, let alone of the complete engine.

Sabre remains a very long way away from being proven to work.

NGNAA (-1)

Anonymous Coward | about a year and a half ago | (#42120533)

failure, its corpse lube or we seel host what the house in a head spinning reciprocating bad

Dumb Question (1)

avandesande (143899) | about a year and a half ago | (#42120543)

Why does the input air need to be chilled? Does this have something to do with using hydrogen in a turbine engine?

Re:Dumb Question (1)

Shoten (260439) | about a year and a half ago | (#42120793)

Why does the input air need to be chilled? Does this have something to do with using hydrogen in a turbine engine?

Design considerations. The front of the engine intake is where they keep all the Coors Light.

Re:Dumb Question (1)

maroberts (15852) | about a year and a half ago | (#42121209)

Why does the input air need to be chilled? Does this have something to do with using hydrogen in a turbine engine?

Design considerations. The front of the engine intake is where they keep all the Coors Light.

Its a British engine - all our beer is warm! We're actually trying for the worlds fastest ice cream van....

Re:Dumb Question (1)

HornWumpus (783565) | about a year and a half ago | (#42121637)

Coors light is not beer.

Re:Dumb Question (1)

Anonymous Coward | about a year and a half ago | (#42120801)

Air with hypersonic speed hits the intake and the shockwaves
that form heat the air to 1000 decrees celsius. That's too hot
for the latter stages, so the air must be cooled.

Re:Dumb Question (4, Informative)

roc97007 (608802) | about a year and a half ago | (#42121219)

Why does the input air need to be chilled? Does this have something to do with using hydrogen in a turbine engine?

Covered here [wikipedia.org] . It's actually an interesting read. Put succinctly, as speed increases, the temperature of the air increases, reducing efficiency.

Re:Dumb Question (2)

Kaitiff (167826) | about a year and a half ago | (#42121307)

clip from online article regarding this intercooler:
But its success depends on the Sabre engine's ability to manage the very hot air entering its intakes at high speed.
These gases have to be cooled prior to being compressed and burnt with the onboard hydrogen.

Skylon would do the job of a big rocket but operate like an airliner from a conventional runway
REL's solution is a module containing arrays of extremely fine piping that can extract the heat and plunge the inrushing air to about -140C in just 1/100th of a second.

Ordinarily, the moisture in the air would be expected to freeze out rapidly, covering the piping in a blanket of frost and dislocating their operation.

But the company's engineers have also devised a means to control the frosting, permitting the Sabre engine to run in jet mode for as long as is needed before making the transition to full rocket mode to take the Skylon spaceplane into orbit.

It is the innovative helium cooling loop with its pre-cooler heat-exchanger that REL has been validating on an experimental rig.

"We completed the programme by getting down to -150C, running for 10 minutes," said Mr Bond. "We've demonstrated that the pre-cooler is behaving absolutely as predicted."

Re:Dumb Question (1)

raxx7 (205260) | about a year and a half ago | (#42121323)

It's not a particular problem with hydrogen or even turbine engines. Pretty much all thermal engines benefit of having a cold air intake
Broadly, two reasons:
- Colder air is denser and it takes less effort to feed more air into the engine, in order to be able to burn more fuel.
- Higher temperatures (can) yield higher efficiencies, but the engines are limited by what engine materials can whistand.

Turbocharged petrol or diesel engines usually have a intercooler to cool down the air between the turbocharger and the engine itself. Some gas-turbine electric plants in hot locations pass the air through a room full of ice before intake.

What these guys did was, taking advantage that they use liquid hydrogen (very cold) as fuel, they cool the air down before the intake, making life easier to everything that comes next.
The tricky part really was designing the heat exchanger.

Re:Dumb Question (1)

HornWumpus (783565) | about a year and a half ago | (#42122083)

Most rocket engines take advantage of the cold liquid H2 to cool their combustion chambers.

If the H2 is already heated the combustion chamber will melt.

Re:Dumb Question (1)

tibit (1762298) | about a year and a half ago | (#42122629)

Boiling of the liquid hydrogen, if you don't want to dump any unburned H2 overboard, will absorb about 1% of the heat needed to be removed from the incoming airstream :)

Re:Dumb Question (1)

tibit (1762298) | about a year and a half ago | (#42122603)

Because otherwise, once you further compress the air to pressures needed for rocket propulsion, it'll be way too hot to handle by any known materials.

SkyActiv (1)

AndyKron (937105) | about a year and a half ago | (#42120935)

My SkyActiv beats your Skylon HA!

life immitates art? (1)

roc97007 (608802) | about a year and a half ago | (#42121161)

Hmm. Looks like kinda a mash-up of Serenity and the Pan Am Space Clipper.

(Is it too late to say "geek alert"?)

Funding and Progress (0)

Anonymous Coward | about a year and a half ago | (#42121213)

Skylon been around long time, this is lasted version. I'm glad their making progress building the thing, getting most critical part of it done.
I think it will be challenge though to get completed, specially with fiancial difficulties everyone having including the goverment.

Maybe Kickstart would help, but that bit too much for Aerospace effort like a single-stage-to-orbit Space Plane.

As for airports, i wasn't under the impression this will be airline/Sub-Orbital Liner, this was suppose to be a space shuttle/plane type. Hope it works out.

The problem with this Brit engine is... (1)

Anonymous Coward | about a year and a half ago | (#42121371)

...Getting the oil stains out of the concrete hangar floor.

They need money? I have two words for them. (1)

NoSalt (801989) | about a year and a half ago | (#42121397)

Richard Branson

Who cares about US airports! (2)

WGFCrafty (1062506) | about a year and a half ago | (#42121457)

Why should we care about it being able to fly at US airports if it needs to launch from the equator?

This is a very neat concept, and it has implications in regular jet travel as well as space travel. The ability to cool air and compress it that much in a regular jet engine could increase efficiency astronomically! The fact that this concept works could mean we see more economical jets before we see this in space travel.

I want the pre-cooler ... (1)

Skapare (16644) | about a year and a half ago | (#42121601)

... for use in global warming summers to get cool air. -140C sounds terrific.

Way Cool! (0)

Anonymous Coward | about a year and a half ago | (#42121657)

Way Cool!! In indeed.

250 million just to design it. No prototype (1)

gedw99 (1597337) | about a year and a half ago | (#42121731)

250 million just to design it according to the article. then a bucket load more. About 10 billion to build it.
And whats the chance it works. Elon Musk poo poo ed in his last interview 1 day ago on video.

Re:250 million just to design it. No prototype (1)

stevelinton (4044) | about a year and a half ago | (#42122155)

I wonder if the engines could be useful even without the plane?

Strap a bunch of them, some disposable LH2 tanks and a parachute onto the side of a Falcon and drop them when you hit Mach 5. Should improve the mass ration no end.

The direction space travel should've taken (4, Interesting)

GodfatherofSoul (174979) | about a year and a half ago | (#42122951)

Many years ago in high school I think, I wrote a report on the X-15 rocket plane. The impression I got was that, while vertical rocket technology got us further faster in the short term, a more gradual development of hypersonic planes would've been better in the long run. We might have had a whole generation of space planes lobbing satellites and even space tourists capsules cheaper, more safely, and with faster turn-around time. I'm not an engineer, so I could be completely full of crap, too.

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