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NASA Successfully Test Fires J-2X Engine.
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.'"
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.
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.
With some improvement... nothing much original ...
Ah, looks like I was thinking of the J-2S, which was apparently also called J-2X early in its development.
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.
Be you Admins? nay, we are but lusers!
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.
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.
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.
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?
"False hope is why we'll never run out of natural resources!" - Lewis Black
So much for the space commute to the orbital ball bearing factory and the weekends on Mars, eh?
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?
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.
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.
When our name is on the back of your car, we're behind you all the way!
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.
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.
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"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.
When our name is on the back of your car, we're behind you all the way!
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.
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.
The SSMEs needed to be reusable. J2 wasn't.
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 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.
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.
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.
I prefer the "u" in honour as it seems to be missing these days.
FTFY. Now the answer is obvious.
Eliminate squabbling and you have rule by consensus. There is no way rule by consensus would produce a moon base.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
How can a single rocket, a tube filled with fuel, cost $10 billion?
It doesn't. That $10G includes development costs.
I can't decide if this post is interesting, funny, insightful, or flamebait.
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.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC