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NASA Successfully Test Fires J-2X Engine.

samzenpus posted more than 2 years ago | from the fire-it-up dept.

NASA 119

tetrahedrassface writes "NASA successfully test fired the J-2X engine Wednesday for 500 seconds at Stennis Space Center. The J2-X is derived from the J2 engine from the Apollo Era, and will power the upper stage of the SLS. From the article: 'We have 500 seconds of good data, and the first look is that everything went great. The J-2X engine team and the SLS program as a whole are extremely happy that we accomplished a good, safe and successful test today,' said Mike Kynard, Space Launch System Engines Element Manager at NASA's Marshall Space Flight Center in Huntsville, Ala. 'This engine test firing gives us critical data to move forward in the engine's development.'"

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at the risk of sounding like a heartless bastard.. (2, Insightful)

Anonymous Coward | more than 2 years ago | (#38008356)

so they rebuilt 1960's technology and it worked...so lets find those old engineers who designed stuff that actually worked and pat them on the back.

Re:at the risk of sounding like a heartless bastar (2, Informative)

0123456 (636235) | more than 2 years ago | (#38008380)

so they rebuilt 1960's technology and it worked...so lets find those old engineers who designed stuff that actually worked and pat them on the back.

If I remember correctly, the J-2X is a substantially improved version of the engine with a few hundred changes over the original J-2, but, yeah, this story would be more interesting if SLS was ever going to fly.

Re:at the risk of sounding like a heartless bastar (3, Insightful)

0123456 (636235) | more than 2 years ago | (#38008418)

Ah, looks like I was thinking of the J-2S, which was apparently also called J-2X early in its development.

Re:at the risk of sounding like a heartless bastar (1)

msobkow (48369) | more than 2 years ago | (#38008670)

I wonder if it's a tribute to the anime?

Saber Marionette J2X [amazon.com]

Funny series, by the way. :)

Re:If they got enough data from this test... (3, Insightful)

taiwanjohn (103839) | more than 2 years ago | (#38012760)

to bring the project in significantly under budget, then yes, the thing might actually fly someday. Otherwise, it's just another waste of money. In the last 10 years, SpaceX has built up an entire booster family (and attendant infrastructure) for less money than SLS is projected to cost per launch .

In a few more years, when SpaceX is flying astronauts to the ISS, and has an even bigger booster than SLS on the drawing board, then SLS will finally die a long overdue death. It's a shame to waste all that money, but when Congress is owned by corporate interests there's no easy way around that.

Re:at the risk of sounding like a heartless bastar (2)

Burdell (228580) | more than 2 years ago | (#38008594)

Hey, that's my dad you're talking about! Dad worked on what was then called the J-2X (a different program from the current J-2X) during the Saturn program, and is still working for NASA on the new vehicles.

Re:at the risk of sounding like a heartless bastar (2, Insightful)

Anonymous Coward | more than 2 years ago | (#38008630)

Well, the 747 first flew in 1969 and it still looks the same today. Some things don't change because they can't, they're already pretty much at the limit of what's possible. Too often people think that because we've gotten better at storing and flipping bits, which requires almost no energy at all, that this means everything else has gotten better too.

So much for the space commute to the orbital ball bearing factory and the weekends on Mars, eh?

Re:at the risk of sounding like a heartless bastar (4, Insightful)

Ethanol-fueled (1125189) | more than 2 years ago | (#38008660)

If the planet weren't busy with squabbling with each other and getting fat with short-term greed, we'd have at least a habitable station on the moon by now.

Re:at the risk of sounding like a heartless bastar (2)

MightyYar (622222) | more than 2 years ago | (#38011206)

Eliminate squabbling and you have rule by consensus. There is no way rule by consensus would produce a moon base.

Re:at the risk of sounding like a heartless bastar (5, Insightful)

Teancum (67324) | more than 2 years ago | (#38010384)

In terms of aviation, there have been substantial improvements in many related technologies that can be applied to commercial aircraft since the original 747 made its first test flight. Indeed the 747 itself has changed many times and what is coming off the production line today in some ways doesn't even resemble the aircraft that was originally produced.

To pull this argument completely to pieces, Boeing even has plans to replace the 747 [wikipedia.org] due to some of the changes in aviation technology that essentially require a complete clean-sheet redesign of the aircraft. There have been improvements in the technology, and sometimes when you have a wide swath of technological improvements it can be a good time to look at something new.

This said, as was the case for the 747 and the original J-2 engine, what is being expected out of these devices is precisely what was wanted when they were original built in the 1960's. It shouldn't be surprising that something very similar is able to perform the very same task. I use a toaster to warm my bread with a device that looks very similar to what my grandmother had when I was a little child.

Re:at the risk of sounding like a heartless bastar (0, Flamebait)

Anonymous Coward | more than 2 years ago | (#38012280)

Yes, but the shape, function and performance hasn't changed to the degree that it's ten thousand times faster, lighter, stronger, etc. It doesn't scale to space. Our technology doesn't, and it won't. Ever. Deal with it. Our "advances" are really about trying to squeeze every last Joule from our dwindling fossil fuels, because we have nothing else.

Look at this comment, for example: "If the planet weren't busy with squabbling with each other and getting fat with short-term greed, we'd have at least a habitable station on the moon by now."

What the christ is so important or appealing about a Moon base? Because you saw a movie or read sci-fi? It's never going to work or be practical, you can put as much carbon fiber as you want in a 747, that won't change the basic reality that space is empty, harsh and deadly, and humans are fragile, short-lived and not adapted for space.

Can it get to Mars? (0)

Anonymous Coward | more than 2 years ago | (#38008362)

Send it up into orbit, stat. The Russians could use a shove.

500? Hardly (0)

Anonymous Coward | more than 2 years ago | (#38008366)

They quite clearly said it was 499.97 seconds runtime!

Smoke? (1)

Anonymous Coward | more than 2 years ago | (#38008378)

That's the best smoke machine I've ever seen.

Re:Smoke? (2)

demonlapin (527802) | more than 2 years ago | (#38008558)

Steam, actually, as vast quantities of the Pearl River are turned into vapor. (Plus the relatively small amount of water vapor made by the combustion of liquid hydrogen.) If you plan to fire a rocket against a fixed point for over eight minutes, you'd better have one hell of a good cooling (and noise-damping) system. Fortunately for them, they do.

Re:Smoke? (5, Informative)

Pseudonym (62607) | more than 2 years ago | (#38008730)

Mist, actually. Steam, which is water in its gas state, is invisible. The bit that you can see is actually an aerosol of water in its liquid state.

The mixture is often referred to as "wet steam", but it's the wet bit that you can see, not the steam bit.

Re:Smoke? (-1)

Anonymous Coward | more than 2 years ago | (#38008982)

:-D

Re:Smoke? (-1)

md65536 (670240) | more than 2 years ago | (#38009050)

Water vapor, actually. Myst, which is a mythical island, is a land in which one uses special books written by an artisan and explorer named Atrus to travel to several worlds known as "Ages".

Re:Smoke? (2)

Teancum (67324) | more than 2 years ago | (#38010416)

No, the term "mist" is more technically correct.

Yes, I get the joke, but you also missed the point and were technically inaccurate all at the same time. Water vapor is just another way of describing steam, but with its partial pressure being much lower due to the fact that it hasn't condensed yet. On the Earth, water vapor is almost always a significant component in the air and is measured as "relative humidity".... also colorless and odorless like steam.

Clouds form (including the stuff in the sky) when the water starts to condense and forms the aerosol that the original GP post was talking about. That liquid water can even be found at temperatures below the freezing point.

Re:Smoke? (1)

demonlapin (527802) | more than 2 years ago | (#38011750)

Touché.

1960's technology (3, Insightful)

deecha (410960) | more than 2 years ago | (#38008402)

With some improvement... nothing much original ...

Re:1960's technology (4, Insightful)

AsmCoder8088 (745645) | more than 2 years ago | (#38008408)

Yeah, well, give them 1960's funding and then they might actually be able to improve upon it...

Re:1960's technology (2)

tyrione (134248) | more than 2 years ago | (#38011122)

Yeah, well, give them 1960's funding and then they might actually be able to improve upon it...

Bring forward through time those same engineers with all of today's advancements and they'll stomp all over today's talent.

Re:1960's technology (2, Insightful)

Anonymous Coward | more than 2 years ago | (#38012056)

I doubt it. I'd expect the Star Trek TNG episode "Relic" would be nearly a documentary on this sort of thing. Old-school engineers worked in a different environment with simpler machines and tools. You'd get a few cases where modern engineers are less willing to push the envelope than the old-school engineers, and a lot of cases where the old school engineer is just in the way, and his "let me tinker with it" attitude causes problems for the complex highly automated modern systems.

I say this having grown up in a family of engineers including aerospace (Grandfather worked for Burrows and GE, Uncle works for Lockheed Martin, both parents and most uncles/aunts are engineers in various fields).

The simple (possibly sad) fact is that modern engineering like modern manufacturing is a lot more modular and automated, much larger scale, and way easier to frack up if someone decides to "screw the rules I'm gonna do it my way". The guy designing module A can't make changes in module C to make his module work better because he has no idea what those changes might do to module B, and the complexity of the entire A+B+C system is sufficient that one person isn't going to be able to fully understand all the details of it.

Re:1960's technology (5, Insightful)

Idarubicin (579475) | more than 2 years ago | (#38013108)

Bring forward through time those same engineers with all of today's advancements and they'll stomp all over today's talent.

Bullshit. Give any group of talented engineers a sense of motivation, a nearly unlimited budget, and clear, specific goals, and they can do wonders.

The Manhattan project reached approximately 1% of all federal spending in its peak year. It had one aim: build an atom bomb. It had one main motivation: keep the bad guys (who had launched a sneak attack on us already) from taking over the world.

The Apollo program touched a massive 2.2% of all federal outlays in its peak year. It had three specifications: Man, Moon, Decade. It had one main motivation: keep the bad guys (who had put a satellite in orbit, and a man in space, first) from taking over the world. (Figuratively or literally, depending on your personal level of paranoia.)

NASA today sees about 0.6% of the federal budget: a proportion which has been shrinking steadily since the early 1990s. That funding is divided across a large number of programs and priorities. Not only do they not have clearly stated goals to guide them, they lack the funding to even maintain continuity in the programs (both scientific and engineering) which already exist.

Today's NASA has some superb engineers that I would readily stack up against those from any era in the agency's history. What NASA lacks is funding and leadership. The problem is political, not technical.

Re:1960's technology (2)

Brett Buck (811747) | more than 2 years ago | (#38008428)

Why would you want someone to start from scratch, when they are approaching the theoretical maximum performance already?

Re:1960's technology (3, Interesting)

toQDuj (806112) | more than 2 years ago | (#38009056)

Because apparently, the Russians do it better (see video). I also remember there being a stock of leftover engines from the end of the cold war (not sure if it was the NK-33), that exceeded the US theoretical predictions on some maximum engine parameters. So there are still lessons to be learned.

http://www.youtube.com/watch?v=-S0zbFD2FqU [youtube.com]

Re:1960's technology (3, Interesting)

Z00L00K (682162) | more than 2 years ago | (#38009474)

And also the Russian RD180 closed loop engines which are designed to also use the energy driving the pumps for propulsion which means that they are more efficient.

So now is the question rather when we will see a Saturn VI on the launch pad...

Re:1960's technology (1)

Anonymous Coward | more than 2 years ago | (#38013188)

The number after Saturn is not a version number... And if we're going to see another super-heavy lifter, I'd much rather see a Falcon XX or the DIRECT team's Leviathan-140 proposal. The Saturn V was an amazing machine, but we can do things much more cost-efficiently nowadays.

Re:1960's technology (3, Insightful)

kermidge (2221646) | more than 2 years ago | (#38009194)

This.

Seems to me that in engineering form tends to follow function. There's only so many practical ways to design an airplane, for instance: tube, wing, or blend; add propulsion, fuel tanks, controls. Then improve materials, fab methods, and play with it - a practical flying wing needed improved controls not available in the early 1900s, for example. http://en.wikipedia.org/wiki/Flying_wing [wikipedia.org]

As for the deprecating discussion of the J-2X above, http://en.wikipedia.org/wiki/J-2_(rocket_engine) [wikipedia.org] seems a reasonable place to start.

As to why we went to Luna and quit [downpage], well, that's been lived through, written about, and discussed up the yin-yang. Seems to me it was largely lack of interest and failure of will abetted by the distractions of a bunch of stuff on the front burner. Looking at the past coupla thousand years I get the impression that in the collective, humanity tends to be short-sighted and rather petty. Ditto for many of its members. Which is why, when we do neat things like invent computers, printing press, microwave ovens, nail clippers, and soap, and remove the scourge of polio, smallpox, and such, I applaud and try not to think overmuch about all the things we're _not_ doing. Yeah, I try; not saying it works.

Re:1960's technology (1)

craigminah (1885846) | more than 2 years ago | (#38011532)

Right...according to Bill Gates "nobody would ever had a need for more than 64,000 lbs of thrust" :)

Re:1960's technology (1, Insightful)

washort (6555) | more than 2 years ago | (#38008472)

That also describes Linux, FWIW. ;-)

Re:1960's technology (4, Insightful)

Burdell (228580) | more than 2 years ago | (#38008620)

I bet you still drive a car with a four-cycle engine, which is 19th century technology. Your car has some improvements, but nothing much original.

Re:1960's technology (1)

Anonymous Coward | more than 2 years ago | (#38009002)

Your analogy supports the person you're replying to: standard car engines aren't interesting either.

Re:1960's technology (1)

Anonymous Coward | more than 2 years ago | (#38008804)

The physics of burning hydrogen and oxygen hasn't actually changed since the 60's either.

Re:1960's technology (0)

Anonymous Coward | more than 2 years ago | (#38008938)

agree

Re:1960's technology (0)

Anonymous Coward | more than 2 years ago | (#38013870)

This is like complaining that the LS6 has nothing on the ol' venerable Chevy small-block V8 dating back to the 1950's. Yet I don't expect to see anybody with a GM vehicle that has that under the hood bitching about how old the design is.

Sometimes once you hit on something that works, it's worth sticking with no matter how dated it may seem. This is also why aircraft like the B-52 or 747 don't really have a replacement on any near-term schedule.

It makes you wonder... (5, Interesting)

acehole (174372) | more than 2 years ago | (#38008434)

If the space race had continued with the vigour that it did instead of petering out after barely a decade, what could have been achieved and what would have already been achieved by now? Instead we reached the moon, gave a high five then twiddled our thumbs in LEO for the next few decades.

It seems to me like it was a lost opportunity not to maintain the speed of exploration.

Re:It makes you wonder... (1)

aztektum (170569) | more than 2 years ago | (#38008662)

We had wars to fight and bombs to drop instead.

Re:It makes you wonder... (1)

Spy Handler (822350) | more than 2 years ago | (#38009726)

and welfare/medicare payments to make

Re:It makes you wonder... (-1)

Anonymous Coward | more than 2 years ago | (#38008736)

Yeah, too bad about the limits of engineering, materials, physics and energy sources, eh? That's the real reason it petered out. The universe is too damn big and technology doesn't scale, certainly our life span doesn't scale. People don't belong in space. Low Earth orbit shouldn't even be called "space", that's like calling "2" infinity and saying you know all about infinity.

Put some machines in space, send some rovers here and there. That's all that's gonna happen in space. The next revolutions will be social, and biological. How's a few extra centuries of life span sound to you? With a social model to match.

But that kind of exploration doesn't appeal to the autistic savants drawn to the grandiose delusions of the Space Age.

Oh, did I mention space is empty? That's why it's called "space", and not Earth.

Re:It makes you wonder... (1)

runner_one (455793) | more than 2 years ago | (#38008800)

Quantum Apostate strikes again.

Re:It makes you wonder... (0)

Anonymous Coward | more than 2 years ago | (#38011944)

Fine. We'll see in ten years. Or a hundred. We'll still be here, both of us. Not on Mars, or mining asteroids. But I'm sure you'll turn down every medical advance that will allow us to live longer, because exploring time is unnatural and scary. Unlike space, which is really just a kind of very big Wal Mart and is full of stuff and is basically easy for humans to deal with.

And "apostate" is very correct. You're probably trying to make some kind of insult or clever word play, I'll bet you don't even know what the word means.

It means: " A person who renounces a religious or political belief or principle."

And that's correct. I used to be a Space Nutter with wide-eyed delusions about how easy space will be, and how we'll all float away into space. It was a faith, a religion. But then I grew up. Reality started getting more and more important, and childish fantasies were left behind.

I urge you do the same.

Re:It makes you wonder... (1)

inasity_rules (1110095) | more than 2 years ago | (#38010856)

Core 1:Where am I? Guess. Guess guess guess. I'm in space.

Core 1:Space Court. For people in space. Judge space sun presiding. Bam. Guilty. Of being in space. I'm in space.

Core 2: There's nothing in space! That's why it's space!

Oh, did I mention space is empty? That's why it's called "space", and not Earth.

In conclusion, it seems slashdot is filled with the personality cores from portal. I rest my case, Judge Space Sun!

the technology wasn't there (1)

Anonymous Coward | more than 2 years ago | (#38008980)

bullshit. Agricultural technology is insufficient today for Mars. Restriction enzymes weren't even discovered until the late 1970s. Look at the fungus on Mir and how it attacked with windows. How about the discovery last year that staying in microgravity for months might be permanently bad for eyesight.

The tech simply is not ready. Mir should have kept in orbit, and the human guinea pigs should have been kept in orbit for longer periods of time. Biosphere 2. That should have been done by, or used by NASA more aggressively. It was financed by a billionare.

I'd argue manned spaceflight in America is pork. pork. pork. pork. Look at the SLS's protectors in Congress. Thank god America has Burt Rutan, John Carmack, Bezos, and Elon Musk.

Re:the technology wasn't there (2)

WindBourne (631190) | more than 2 years ago | (#38010748)

Actually, HSF is not really pork. SLS is pork. However, most of NASA's HSF prefers the approach of pursuing private space doing multiple launchers, inflatable space station, and fuel depots, while NASA focuses on a nuke transportation (nerva), VTVL for the moon and mars. Sadly, L-Mart, Boeing, ATK, northrup,etc and a mostly neo-con push prefer the pork.

Re:It makes you wonder... (3, Funny)

bill_mcgonigle (4333) | more than 2 years ago | (#38009020)

what could have been achieved and what would have already been achieved by now?

We'd have an extra small sun in our sky, as of last year. Actually, I saw it pretty clearly next to the moon tonight.

Re:It makes you wonder... (0)

thatskinnyguy (1129515) | more than 2 years ago | (#38009594)

What? Jupiter? It does put out more radiation than it absorbs but it's hardly a sun.

Re:It makes you wonder... (1)

notmyusualnickname (1221732) | more than 2 years ago | (#38009996)

What? Jupiter? It does put out more radiation than it absorbs but it's hardly a sun.

Whoosh. (See the works of Sir Arthur C Clarke for details...)

Re:It makes you wonder... (2)

WindBourne (631190) | more than 2 years ago | (#38010722)

Actually, it was not us that twiddled. USSR stepped things down once we hit the moon. Had they not stepped down, then we would have continued. The problem is that it was expensive to them as well as to us. That is why USSR quit the high spending, followed by Nixon doing the same.

Re:It makes you wonder... (1, Insightful)

ThatsNotPudding (1045640) | more than 2 years ago | (#38011210)

You are labouring under the mistaken belief that the Space Race was not just thinly veiled ICBM R&D.

Re:It makes you wonder... (2)

DerekLyons (302214) | more than 2 years ago | (#38013744)

You are labouring under the mistaken belief that the Space Race was not just thinly veiled ICBM R&D.

That's just the thing - it wasn't. While it's true that the early space boosters were based on IRBM's and ICBM's, the technology rapidly diverged.

Uhm, maybe I don't get it (1)

GReaToaK_2000 (217386) | more than 2 years ago | (#38008452)

But I expected a large afterburner like exhaust.

It looked like a giant smoke machine.

Re:Uhm, maybe I don't get it (-1)

Anonymous Coward | more than 2 years ago | (#38008490)

But I expected a large afterburner like exhaust.

It looked like a giant smoke machine.

You could try something crazy and totally unrealistic to expect from a literate person with Internet access: look it up via Google or Wikipedia.

Then you'd know. Then you might have something meaningful to add to the discussion. Oh and it'd be faster than writing your post.

Am I setting the bar too high again?

Re:Uhm, maybe I don't get it (1)

GReaToaK_2000 (217386) | more than 2 years ago | (#38008520)

I love wanna be intellectuals commenting like they are being funny. I was joking around you ass-hat.

Anyway, if you want, here's something for you to chew on dim whit.

According to what I found online the J-2X looks like it's a step backwards. According to the data on wiki it's bigger, heavier, produces less thrust than the J-2S therefore causing it's thrust to weight ratio to be less than BOTH the J-2 and J-2S.

No, you're not setting the bar too high, but apparently you bar is low enough most won't trip over it.

I shouldn't expect much of a comment from someone who has a ID number in the tens of millions.

Re:Uhm, maybe I don't get it (1)

wagnerrp (1305589) | more than 2 years ago | (#38009162)

According to the data on wiki it's bigger, heavier, produces less thrust than the J-2S therefore causing it's thrust to weight ratio to be less than BOTH the J-2 and J-2S.

Bigger, heavier, and less power-to-weight, however it is more powerful and more efficient. That's all fairly irrelevant. Fuel is cheap, rocket motors are expensive. The original J-2 damned the cost to beat the Ruskies. The RS-25 was recovered with the Shuttle, although that had to be rebuilt after each launch and didn't work out as planned. The J-2X is redesigned using less exotic materials and less complex construction methods. It is supposed to be cheaper, so it is less of a problem to be disposable. Whether this pans out and saves enough to be worth the additional development cost is yet to be seen.

I shouldn't expect much of a comment from someone who has a ID number in the tens of millions.

Huh? Anonymous cowards don't get ID numbers, and even then, new users are in the high two million range.

Re:Uhm, maybe I don't get it (2)

Professr3 (670356) | more than 2 years ago | (#38008506)

They fire the engine into a torrent of running water, so it doesn't melt the test platform (and to keep down toxic combustion products). The smoke was actually steam. Lots of steam.

Re:Uhm, maybe I don't get it (0)

GReaToaK_2000 (217386) | more than 2 years ago | (#38008544)

I figured as much, I was goofing around because I was disappoint to not see the exhaust. I grew up on an air base and loved watching the jets take off. I've seen three of the shuttles go up as well as Voyager 2 leave the Earth as well.

Re:Uhm, maybe I don't get it (0)

Anonymous Coward | more than 2 years ago | (#38008574)

Toxic by-products? What are you smoking? It burns Hydrogen and Oxygen, sure water is corrosive, but I wouldn't call it toxic!

Re:Uhm, maybe I don't get it (2)

camperdave (969942) | more than 2 years ago | (#38008706)

Toxic by-products? What are you smoking? It burns Hydrogen and Oxygen, sure water is corrosive, but I wouldn't call it toxic!

It doesn't burn cleanly, and because they are firing the engine in the atmosphere, there will be byproducts of atmospheric gasses in the exhaust as well. That means HNO3, HCN, NH2, NH3, and who knows what else.

Sorry, you don't get it (3, Informative)

dbIII (701233) | more than 2 years ago | (#38008724)

When burning stuff in air you get various nasty nitrogen oxides that turn into nitric acid once they hit the fluid in your lungs. That's with the cleanest flame you can get and that's a major reason why power stations have scrubbers. There's other stuff like a fuel the Russians used to use that is far nastier and even the unburnt liquid will make you sick if it gets on your skin.

Re:Sorry, you don't get it (0)

EETech1 (1179269) | more than 2 years ago | (#38009078)

So they don't just mix the hydrogen and oxygen in the combustion chamber and light the bitch? They somehow force outside ambient air in there too?

Re:Sorry, you don't get it (2, Insightful)

Anonymous Coward | more than 2 years ago | (#38009288)

So they don't just mix the hydrogen and oxygen in the combustion chamber and light the bitch? They somehow force outside ambient air in there too?

The air doesn't have to be forced in because the flame is forcing itself out.

You idiot. No, I don't say that because I think you are stupid. I don't think you are stupid. I think you could have figured this out on your own. Your objection was absurd and that's your cue that you were looking at it incorrectly. There was only one other way to look at it. This is trivial search space of exactly 2 items. How much easier does it have to be, you one-track minded simpleton?

It's a shame schools teach people what to think but not how to think.

Re:Sorry, you don't get it (0)

EETech1 (1179269) | more than 2 years ago | (#38009806)

So where does this outside ambient air come from while in space?

Looking at:
pw.utc.com/products/pwr/propulsion_solutions/j-2x.asp.

I see:
Pressure-Combustion Chamber: 1,380 psia

This will somehow suck in outside ambient air at 15 psia on the ground, or better yet! 0 psia in space? Please tell me how?

I'm really excited to learn this! perhaps you could set me up with a lmgtfy link?

And what am I objecting to?

That it doesn't appear to use anything but hydrogen and oxygen in the combustion chamber, so it would seemingly produce nearly all water vapor as the exhaust, and since it does not seem to use ambient air in the process it should not have nitrogen floating around in the combustion chamber to combine with leftover oxygen form NOX and other nasty byproducts?

Did ya miss that AC?

Can ya explain how the nasty stuff from the outside ambient air gets in the combustion chamber to react when it's at 1350 psia and contaminate the normally clean (hey I thought that made water) hydrogen oxygen combustion process?

Extra bonus if you explain, or Google link is fine, how outside ambient air gets in a rocket engine while in space!

Because that's what we're taking about here...

If you had a UID I might consider discussing your super sucky flame theory some more, but since you troll as AC....

DIAF - noCheers4u

APK if you're out there... Please add this jerkoff to your hosts file!

Re:Sorry, you don't get it (1)

MightyYar (622222) | more than 2 years ago | (#38011814)

This test wasn't carried out in space - it was carried out on a test stand on the ground. Air isn't "sucked in" to the combustion chamber, but the flame and exhaust are exposed to the atmosphere, and it is still quite hot at that boundary. Many nitrogen byproducts result. Shooting the exhaust at a waterfall helps to mitigate this.

Test was on the ground with a flame in air (1)

dbIII (701233) | more than 2 years ago | (#38012028)

So where does this outside ambient air come from while in space?

If it's in space you don't fucking care about the emissions anyway because nobody is there to breath the stuff. What is it about this increasingly common trend here of deliberately pretending to be dumb to "win" an argument after a mistake has been made? Is it due to some bad example from politics or something?

Can ya explain how the nasty stuff from the outside ambient air gets in the combustion chamber to react when it's at 1350 psia and contaminate the normally clean (hey I thought that made water) hydrogen oxygen combustion process?

Look at a photo of a rocket in action. Notice that great big flame coming out. Since the test was in an atmosphere you would get some NOx from that flame burning in air which is one reason to have water available to stop it being a problem.
This is all pointless anyway because you do not seem to be understanding (or more likely pretending not to understand) the difference between discussing things in general and not specifics. I was pointing out something about combustion in air that you did not appear to be aware of.

500 seconds... (1)

inexia (977449) | more than 2 years ago | (#38008526)

Roughly 3 million taxpayer dollars a second for basically nothing?

Nothing to see here: (1)

Hartree (191324) | more than 2 years ago | (#38008586)

It didn't make your intarwebs faster or your graphics resolution on WoW better, so you can safely go back to sleep and just ignore it.

Fuel is cheap (3, Interesting)

wagnerrp (1305589) | more than 2 years ago | (#38009340)

1310kN (thrust) / 448s (specific impulse) = 298kg/s exhaust mass flow rate
298kg/s * 1/9 = 33kg/s hydrogen mass flow rate * $5.50/kg = $181.50/s
298kg/s * 8/9 = 265kg/s oxygen mass flow rate * $3/kg = $795/s

$181.50/s + $795.00/s = $976.50/s

In other words, you're looking at under a thousand dollars per second to run the rocket motor, and about half a million for the total burn. Fuel is cheap, the real cost is in the vehicles themselves. That was the whole reason the Shuttle was supposed to be reusable. Had the Shuttle worked as intended, we would be looking at payload costs on the order of $2000/kg rather than the $20000+/kg it saw in practice. The problem with the Shuttle was the costly inspection and refurbishment after each flight.

Re:Fuel is cheap (2)

inexia (977449) | more than 2 years ago | (#38009458)

I must commend you on the the fuel breakdown! My comment, however, was way beyond the fuel cost as that is negligible. I was thinking more on the legacy costs of overhead, engineering, production, etc. Given a budget of a couple hundred million and the number of years to create a prototype arrived me to my previous statement.

Space Shuttle Main Engine (1)

flyingfsck (986395) | more than 2 years ago | (#38008608)

Uhmm, wasn't the Space Shuttle main engine also a J2 derivative? The J2 has been redesigned many times over the decades. It likely doesn't look much like the original drawings anymore...

Re:Space Shuttle Main Engine (2)

agentgonzo (1026204) | more than 2 years ago | (#38010176)

The SSMEs needed to be reusable. J2 wasn't.

Liquid hydrogen and liquid oxygen as fuel... (2, Informative)

cplusplus (782679) | more than 2 years ago | (#38008624)

The article says the J2-X uses liquid oxygen and liquid hydrogen as fuel. Does that imply the byproduct of the J2-X is water vapor? The old Apollo rockets used kerosene. I know NASA used a lot of water to control heat and vibration for shuttle launches and other rocket tests (which is likely what you see in the video)... but is that also the exhaust gas here?

Re:Liquid hydrogen and liquid oxygen as fuel... (4, Informative)

trout007 (975317) | more than 2 years ago | (#38008640)

The first stage engines F-1 were kerosene and oxygen. The J-2 wereon the second and third stage and were hydrogen and oxygen.

Re:Liquid hydrogen and liquid oxygen as fuel... (5, Informative)

Sooner Boomer (96864) | more than 2 years ago | (#38008698)

The article says the J2-X uses liquid oxygen and liquid hydrogen as fuel. Does that imply the byproduct of the J2-X is water vapor? The old Apollo rockets used kerosene. I know NASA used a lot of water to control heat and vibration for shuttle launches and other rocket tests (which is likely what you see in the video)... but is that also the exhaust gas here?

 
Most of the white stuff you see in the video is steam from cooling and sound supression systems. But, in EVERY combustion in air, even if burning pure hydrogen and oxygen, there is some amount of nitrous oxides produced from the nitrogen present in air. This is an inescapable fact of chemistry. But what you're seeing is water vapor.

Re:Liquid hydrogen and liquid oxygen as fuel... (3, Informative)

WindBourne (631190) | more than 2 years ago | (#38010658)

The amount of NOx produced from a rocket that uses LOX is negligible for the load. The reason is because the actual burn occurred with the O2, not atmosphere. OTH, Jet engines produce a LOT of NOx. It will be many many many times more than a rocket engine. In addition, there is hybrid engines that use nitrous oxide. That will produce a lot of NOx.

Re:Liquid hydrogen and liquid oxygen as fuel... (1)

DerekLyons (302214) | more than 2 years ago | (#38013790)

The amount of NOx produced from a rocket that uses LOX is negligible for the load. The reason is because the actual burn occurred with the O2, not atmosphere.

Yes, and no. While actual combustion of fuel and oxidizer takes place within the engine, the combustion products are still hot enough to cause reactions between atmospheric nitrogen and oxygen. The real reason they produce negligible amounts is because they spend so little time in the atmosphere. On the gripping hand, a good deal of what they do produce is deposited in the upper layers of the atmosphere - precisely the last place you want to do so. (Especially in the ozone layer.)

Re:Liquid hydrogen and liquid oxygen as fuel... (0)

Anonymous Coward | more than 2 years ago | (#38012084)

Check this video : http://www.youtube.com/watch?v=BIpeNs5OWbo

Re:Liquid hydrogen and liquid oxygen as fuel... (0)

Anonymous Coward | more than 2 years ago | (#38012504)

For the shuttle launches, there would be almost 3' of water on the pad to help dampen the shockwaves and such.

Why are they doing this? (3, Insightful)

inhuman_4 (1294516) | more than 2 years ago | (#38008636)

Hasn't the general consensus been that Russian approach of having numerous cheap launchers better than one big powerful one? Why is money still being wasted on designing a huge launcher that won't be ready for years? Can't NASA just man rate some existing Delta or Atlas launchers, or give SpaceX a little more cash?

Re:Why are they doing this? (3, Informative)

Bomazi (1875554) | more than 2 years ago | (#38008722)

Man-rating the Delta and optionally funding a heavy (modular) variant of the Delta and Falcon is the most cost-effective strategy. Unfortunately, it is about keeping the money flowing toward the districts that built the shuttle, not about cost-effective space exploration. Since the space program is a fairly unimportant political issue, congress gets away with it.

Re:Why are they doing this? (2)

WindBourne (631190) | more than 2 years ago | (#38010698)

Only for 2 more years. Once Falcon Heavy launches, SLS will be killed. The reason is that SLS will only carry 70 tonnes from 2021 until around 2030. Then it was slatted to have 140 tonnes around 2030. And SpaceX will likely have 70 tonnes by 2016, and 140 tonnes by 2021.

Re:Why are they doing this? (0)

Anonymous Coward | more than 2 years ago | (#38011598)

They could, but it wouldn't put the pork in the right districts to get congressional votes.

Re:Why are they doing this? (0)

Anonymous Coward | more than 2 years ago | (#38011992)

because congress (Republicans) told them to. Remember, government can't do anything right.

Unless it's not doing it right in my state.

Re:Why are they doing this? (-1)

Anonymous Coward | more than 2 years ago | (#38013276)

This is a one-size-fits-all approach.

President Barack Hussein Obama had to do something *different* than President George W. Bush.

President Bush had a small man-rated rocket, Aries I, for light payloads like people, and a cargo vehicle Aries V for heavier payloads.

President Hussein (Obama) demanded a one-size-fits-all approach, because that's just the way he is. See Obamacare. His rocket has a third less heft of President Bush's, but he got his media to call it "giant" and painted it with an Apollo scheme so it fooled his simplistic supporters.

He had to ensure that his rocket will be too big to use for small things, and too small for anything serious.

Anything else would make the United States look too good.

Never trust a committee (2)

camperdave (969942) | more than 2 years ago | (#38008852)

"For early flights SLS has an 8.4-meter diameter core with three RS-25D/E engines, 8.4-meter upper stage with a J-2X engine, and two 5-segment solid rocket boosters." [wikipedia]

In other words, this is Direct's Jupiter J231, which they could have launched in 2012 instead of 2020.

DVDs@wholesale free shipping cheap wholesale Dvds: (-1)

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NASA needs more bean counters (0)

Anonymous Coward | more than 2 years ago | (#38009388)

Or are they also not buying into the bullshit cost savings served up by our friend Elon Musk?

SLS: Cart before the horse (4, Insightful)

Spy Handler (822350) | more than 2 years ago | (#38009956)

Reaction from the Mars Society:

The Space Launch System HLV (Heavy Lift Vehicle) as currently designed is fine. However, NASA's human spaceflight program needs a mission.

NASA's proposed SLS-HLV budget of $3 billion per year is much higher than is actually needed to fund an HLV, and appears to be an effort to spend the former Shuttle program funds for political purposes.

NASA needs a deep space mission. From the mission comes the plan; from the plan comes the things necessary for its implementation. NASA needs to fund missions, not things. The mission comes first.

This is exactly right. Apollo was successful because it started with a goal, to land a man on the moon. Kennedy didn't say "Let's build a big Saturn V booster and see what we can do with it later". If he had, it would've almost certainly led to program cancellation later by a Congress asking "What the hell are we spending all this money for?"

The SLS program as it stands now is guaranteed to be cancelled. (but not before many billions are funneled to the well-connected)

NASA today is not the young NASA of the 60's. It's become a bloated bureaucracy.

Pournelle's Iron Law of Bureaucracy:

In any bureaucracy, the people devoted to the benefit of the bureaucracy itself always get in control and those dedicated to the goals the bureaucracy is supposed to accomplish have less and less influence, and sometimes are eliminated entirely.

Burt Rutan:

NASA's become a jobs program.

Re:SLS: Cart before the horse (4, Informative)

WindBourne (631190) | more than 2 years ago | (#38010634)

I should mod you down, but will respond instead. The saturn was started in the 50's. Even the test systems was done in 1960-1962, BEFORE kennedy's speech. Are you surprised? You should not be. Presidents do not like to be made a fool of. Kennedy KNEW that it was possible to go to the moon. More importantly, Kennedy was told beforehand that we were ahead of USSR with rocket tech (for BMs). Where we lacked was human space time and the testing required.

What is important is NOT the construction of a rocket, or even a mission. What is important is having tested designs, manufacturing lines, and having it be CHEAP. From that, you can move forward quickly. For example, it took musk 10 years to build his F9. It will take 2 years to build Falcon Heavy. And if things go well, then Musk will likely build Falcon XX in under 5 years. But the important thing is that Musk will build it CHEAP.

OTH, SLS is simply a continuation of Ares V. Same damn SRBs. Same SME. Same J2X. The difference is that SLS is simply being pushed now with a different name. But we already spent 7 years on Ares. Now to get a TEST launch of a 70 tonne system, it will be another 7 years. The first launch of a human? 10 years and over 20 billion just on the SLS. That does not include the 10 billion that we spent on ares already. Of course, SLS will die in about 2 years when Falcon Heavy works. The FH will take up 54 tonnes at that time. Musk is follow it with Raptor second stage which will give FH 70 tonnes. All by 2016. The real issue is that FH with the raptor will still cost around 1/10 of what the SLS costs to launch. That will lead CONgress to kill the SLS (thank god). Once CONgress will allow NASA to focus on doing BEO tech, THEN we can have missions. LOTS OF MISSIONS. But we need a stable of tested equipment and the ability to do it cheaply and quickly.

Re:SLS: Cart before the horse (0)

Anonymous Coward | more than 2 years ago | (#38013306)

LOTS OF MISSIONS! We'll have MORE MISSIONS THAN YOUR NATION CAN HANDLE! Because the new rocket engines will be fueled by POWERTHIRST!

Mist Machine! (1)

Silpher (1379267) | more than 2 years ago | (#38010180)

Thats a nice mist machine! I wanna go dance in front of it! :)

Back to the Future ! (1)

Latinhypercube (935707) | more than 2 years ago | (#38010286)

Back to the Future !
How about sticking an Ion jet on the payload only ? BooYah Focus ground based Frickin' Lasers ?

10 billion? (1)

Lord Lode (1290856) | more than 2 years ago | (#38011016)

The article says the rocket costs $10 billion.

The whole Large Hadron Collider cost $9 billion.

How can a single rocket, a tube filled with fuel, cost $10 billion? Please explain.

Re:10 billion? (2)

Arlet (29997) | more than 2 years ago | (#38011058)

How can a single rocket, a tube filled with pork, cost $10 billion? Please explain.

FTFY. Now the answer is obvious.

Re:10 billion? (1)

Loadmaster (720754) | more than 2 years ago | (#38012050)

How can a single rocket, a tube filled with pork, cost $10 billion? Please explain.

FTFY. Now the answer is obvious.

Dr. Spengler: I'm worried, Arlet. It's getting crowded in there and all my data points point to something big on the horizon.

Winston: What do you mean, big?

Dr. Spengler: Well, let's say this hot dog represents the normal amount of pork for NASA. Based on this morning's test, it would be a hot dog. . . thirty-five feet long, weighing approximately six hundred pounds.

Winston: That's a big hot dog.

Re:10 billion? (2)

Indiana Joe (715695) | more than 2 years ago | (#38011640)

How can a single rocket, a tube filled with fuel, cost $10 billion?

It doesn't. That $10G includes development costs.

Re:10 billion? (0)

Anonymous Coward | more than 2 years ago | (#38012212)

Well, "a tube filled with fuel" is a little simplistic. BUT, remember that NASA does not really build anything (I am simplifying here too) but rather contracts with corporations to do the work at cost-plus. You have multi-layered bureaucracies all sucking on the hind tit of NASA. I am a BIG NASA supported but the costs have to be controlled. Space-X gets the job done because they to the job themselves.

J2-X or J-2X? (0)

Anonymous Coward | more than 2 years ago | (#38012424)

Which is it? The article uses it both ways... Is there an editor in the house?!

Safety first....? (1)

sackbut (1922510) | more than 2 years ago | (#38013616)

In the video there is a gentleman looking through a periscope (1'08") in what I would interpret to be the bunker in case of explosion (with a couple of red covered kill switches?). Then shortly after (1'30"), while the rocket is still burning, it shows a large group of people watching from a relatively short distance away. What gives? Not that I wouldn't mind seeing something like that relatively close!
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