


NASA Successfully Test Fires J-2X Engine. 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.'"
at the risk of sounding like a heartless bastard.. (Score:2, Insightful)
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: (Score:3, Informative)
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 (Score:4, Insightful)
Ah, looks like I was thinking of the J-2S, which was apparently also called J-2X early in its development.
Re: (Score:2)
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... (Score:4, Insightful)
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: (Score:3)
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: (Score:2, Insightful)
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 (Score:4, Insightful)
Re: (Score:3)
Eliminate squabbling and you have rule by consensus. There is no way rule by consensus would produce a moon base.
Re: (Score:2)
Yes, there is always the benevolent dictator path - though you get the good (like a string of economic growth) with the bad (almost constant rioting and general human rights abuses). Though China is far more complicated than a simple dictatorship - there is actually quite a bit of conflict behind the scenes - it's just that at the end of the day there is only one party.
Re:at the risk of sounding like a heartless bastar (Score:5, Insightful)
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: (Score:2)
Actually the risk is more one of sounding like you were too lazy to do even the most basic google search and reading about the J-2X.
There were multiple reasons why the J-2 was selected as the base starting point for a secondary stage engine, mainly the existing performance parameters from the original design and the cost savings gained by not starting from scratch.
However, the J-2X actually has a significant amount of R&D that have gone into improvements w
Smoke? (Score:1)
That's the best smoke machine I've ever seen.
Re: (Score:3)
Re:Smoke? (Score:5, Informative)
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: (Score:3)
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 t
Re: (Score:2)
1960's technology (Score:3, Insightful)
With some improvement... nothing much original ...
Re:1960's technology (Score:5, Insightful)
Re: (Score:3)
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: (Score:2, Insightful)
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
Re:1960's technology (Score:5, Insightful)
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: (Score:3)
Re: (Score:3)
Why would you want someone to start from scratch, when they are approaching the theoretical maximum performance already?
Re:1960's technology (Score:4, Interesting)
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 (Score:4, Interesting)
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: (Score:1)
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: (Score:2)
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...
And then a Gemini successor, then revive the Mercury program...
Re: (Score:1)
Re:1960's technology (Score:4, Insightful)
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: (Score:2, Insightful)
Re:1960's technology (Score:5, Insightful)
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: (Score:1)
Your analogy supports the person you're replying to: standard car engines aren't interesting either.
Re: (Score:1)
You are correct. It is totally pathetic.
We should be driving electric cars with motors at all 4 wheels and magnetic shocks so that the car rides on a blanket of repulsive magnetic force.
Re: (Score:1)
The physics of burning hydrogen and oxygen hasn't actually changed since the 60's either.
It makes you wonder... (Score:5, Interesting)
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: (Score:2)
We had wars to fight and bombs to drop instead.
Re: (Score:2)
the technology wasn't there (Score:1)
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 mo
Re: (Score:3)
Re: (Score:2)
At the very least, periods of time like 2-5 years. Recovering from that is not much worse than recovering from a 5 year coma, right?
Re:It makes you wonder... (Score:4, Funny)
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: (Score:1)
Re: (Score:1)
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: (Score:3)
Re: (Score:2, Insightful)
Re: (Score:3)
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.
Re: (Score:2)
Re: (Score:2)
But it doesn't live on as a weapon system. In fact, even as the space race was getting going, the liquid fueled IRBM's and ICBM's were starting to be phased out. (Thor deployments ended in 1962.)
You really don't know nearly as much as yo
Re: (Score:1)
Quantum Apostate strikes again.
Re: (Score:2)
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!
Uhm, maybe I don't get it (Score:1)
But I expected a large afterburner like exhaust.
It looked like a giant smoke machine.
Re: (Score:3)
Re: (Score:3)
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 (Score:4, Informative)
Re: (Score:2, Insightful)
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 p
Re: (Score:2)
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 (Score:2)
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?
Re: (Score:2)
Re: (Score:1)
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
Re: (Score:2)
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
Nothing to see here: (Score:2)
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 (Score:4, Interesting)
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: (Score:1)
Space Shuttle Main Engine (Score:2)
Re: (Score:3)
Liquid hydrogen and liquid oxygen as fuel... (Score:3, Informative)
Re:Liquid hydrogen and liquid oxygen as fuel... (Score:5, Informative)
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... (Score:5, Informative)
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... (Score:4, Informative)
Re: (Score:2)
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 pro
Why are they doing this? (Score:4, Insightful)
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: (Score:2, Informative)
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: (Score:3)
Re: (Score:2)
...assuming everything goes well. I agree--keep them both running. It'll keep everybody honest.
Re: (Score:2)
However, I will say that I remain a fan of KILLING SLS. Instead, I would like to see NASA do a COTS-SHLV. Basically, provide for 2 SHLV of say 140-160 tonnes. NASA will then provide 5 billion and up to 5 years for development. In addition, each launch MUST be below
Never trust a committee (Score:3)
In other words, this is Direct's Jupiter J231, which they could have launched in 2012 instead of 2020.
SLS: Cart before the horse (Score:5, Insightful)
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 (Score:5, Informative)
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 (Score:5, Informative)
Not just the Saturn - the Apollo CSM was already in development[1] and was in the process of morphing from being the lunar lander to being the command ship with a separate lunar lander. The (in)famous mode debate over direct ascent vs. EOR vs. LOR was already underway.
Few people realize that direct ascent was even in the race, because by 1962 it was already slipping into third place because it was believed that the booster required would be too large to build and fly within the state-of-the-art. The funny part is that NASA so badly underestimated the size and weight of the spacecraft[2] needed to reach the moon, the Saturn V of 1967 ended up being much larger than the Nova they didn't think could be built in 1962.
Precisely this. Kennedy and his advisers looked wide and deep at the various technology projects underway in the US at the time, and choose the lunar landing because a) it was In Space (the primary battleground), and b) considerable research and engineering had already been done. The various popular histories of the era even down to today merely repeat the propaganda of the time, that NASA started from more-or-less a standing start.
Indeed. And once the US got going, the Soviets fell ever further behind, and in some ways they never recovered. Even when it comes to space stations - the Soviets wouldn't beat either the total time accumulated or individual flight lengths until years after Skylab. (Which was essentially a program run with the scraps of the Apollo program.)
[1] Yes, Apollo predates Gemini by a wide margin - and NASA's decision to stick with the existing Apollo (what become the Block I Apollo) would come back to bite them in the butt.
[2] NASA's difficulties with estimating size, weight, budget, and schedule goes back a long ways.
Re: (Score:2)
As the poster above explains, you're understanding of the history of NASA in the 60's is a bit... deficient. The 'young NASA' of the 60's wasn't what you believe it to be, it was in fact a greatly bloated bureaucracy. I wish I could find the flowchart I once saw listing the process it took to approve the adding of a tool to the flight manifest - it took up three pages of reviews and tests and approvals and oversight committees
Mist Machine! (Score:1)
Thats a nice mist machine! I wanna go dance in front of it! :)
10 billion? (Score:2)
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: (Score:3)
FTFY. Now the answer is obvious.
Re: (Score:1)
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: (Score:2)
How can a single rocket, a tube filled with fuel, cost $10 billion?
It doesn't. That $10G includes development costs.
Re: (Score:2)
The LHC is basically an almost empty tube that doesn't go anywhere. When you consider the difference between the mass of a few protons vs. a full load of rocket fuel, you will see that the $10 billion tube has an amazingly better $/kg payload ratio compared to the $9 billion dollar tube, while only having a ~10% cost difference. Th
Safety first....? (Score:1)