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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.'"
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!
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?
The first stage engines F-1 were kerosene and oxygen. The J-2 wereon the second and third stage and were hydrogen and oxygen.
I love Jesus, except for his foreign policy.
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.
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.
Chaos maximizes locally around me.
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.
sub f{($f)=@_;print"$f(q{$f});";}f(q{sub f{($f)=@_;print"$f(q{$f});";}f});
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.
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.
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.
I prefer the "u" in honour as it seems to be missing these days.
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