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Battle of the Heavy Lift Rockets
schwit1 writes: Check out this detailed and informative look at the unspoken competiton between NASA's SLS rocket and SpaceX's planned heavy lift rocket. It's being designed to be even more powerful than the Falcon Heavy. Key quote: "It is clear SpaceX envisions a rocket far more powerful than even the fully evolved Block 2 SLS – a NASA rocket that isn't set to be launched until the 2030s." The SpaceX rocket hinges on whether the company can successfully build its new Raptor engine. If they do, they will have their heavy lift rocket in the air and functioning far sooner than NASA, and for far less money.
There have been way too little competition in this area the last decades. Considering that the Russian RD-180 engines designed in the 70's&80's are still seen as state of the art it is obviously a stagnant situation.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
Mr. Mueller then later updated his numbers at a follow-on conference to portray 6,900 kN of sea-level thrust, and 8,200 kN of vacuum thrust.
That took me 20 seconds to find.
Come on, its Slashdot, at least give us some technical information to back up the story.
If anyone can get it done, it will be Elon Musk and SpaceX. They have the vision and agility that NASA lost in the sixties.
NASA never wanted to build this rocket. It was forces in them from Congress. Plus NASA doesn't build rockets it overseas other aerospace contractors.
I love Jesus, except for his foreign policy.
I mean seriously, look at the SLS, it's almost entirely composed of re-used space shuttle parts. It has the main engines on the bottom of the tank re-purposed from the shuttle. it has solid rocket boosters which already exist from the shuttle -- it entirely looks like it could be cobbled together in a few month's time because it uses almost entirely existing components.
So what exactly requires so many years to make it al work when it's all basically existing tech from the shuttle? I hate to say this, but this ain't rocket science.
If telephones are outlawed, then only outlaws will have telephones.
Well, either rocket can be used for non-pork purposes. There's no physical limitation that prevents them from being used that way. But one of them is going to be well priced out of doing anything that doesn't have huge funding from some government, the congressional one versus one which can be priced to sell to groups other than governments, the SpaceX one. My take is a really cheap big rocket would have takers. Either bigger satellites, more delta-v, and/or launching more satellites at one time.
NASA would be very happy to let SpaceX build a heavy lift booster for them. Really.
The only reason SLS exists is to keep the congresscritters from the former shuttle supply chain districts happy. That's it. NASA is desperately trying to keep funding going, and they ain't interested in pissing that money away on designing big dumb rockets, but politics says that they must to survive. Rockets are rapidly becoming a commercial technology, which is a good thing.
NASA would be very happy to buy rockets from Elon Musk and/or whoever else can put up competing articles. NASA would much rather be doing and spending its hard-fought budget on things that they do well, pushing the envelope on technologies for hard problems, like getting our asses to Mars, and science missions.
Left MS Windows for Linux Mint and never looked back!
Vote for Bernie in 2016!
There are no miracles in rocket engine design. The RD-180 has pretty much the best performance to be wrung out of a sea-level-to-altitude LOX/RP-1 motor in terms of efficiency. SpaceX is still playing catchup in that area, trading off the lower cost per Merlin motor for a lower Isp from a simpler design.
As for the Raptor the "new" liquid-methane/oxygen fuel mix it will burn has the potential to produce a higher Isp than the current mainstream LOX/RP-1 mix used in motors like the Merlin, the RD-180 etc. but it comes with downsides -- it means a redesign of the rocket structure to support fully cryogenic tankerage (although not requiring the sorts of extreme temps or processing LH needs), launchpad facilities for fuelling and defuelling rockets will need to be revamped, liquid methane is half the density of RP-1 so the tanks and the rocket structure need to be larger and heavier to contain equivalent amounts of fuel and so on.
http://www.cbsnews.com/news/ne...
'One spectacular explosion' - One explosion would be 92% reliability. (one failure in 12 launches)
I Don't no https://www.youtube.com/watch?...
For those of you who visited the link, Nasaspaceflight.com has a very well-informed stable of posters, many of whom are professionals in the space industry, and there is the L2 section where you will find much that is not available anywhere else.
BFR? Big F*ing Rocket?
Have gnu, will travel.
A rocket is a mass driver, and all of the "scifi" types of propulsion break the laws of physics one way or another. Space elevators would be pretty nice, but we still haven't found a material strong enough. Carbon nanotubes are the current hope, but we can't make them long enough yet; they'd have to be very long indeed to make a strong enough elevator. Short nanotubes have to be glued together and then you're down to the strength of the glue.
Thank you for that very well documented argument. As soon as I'm done reading all the sources you posted, I'll get back to my morning coffee.
One thing people forget, is that the Private sector, can often do things a great deal faster as there is way less red tape. In the Public Sector, you have to have more justification on who you buy everything from, to contractors, everything. The public sector is greatly hindered by this in so many ways, to make sure everything is above board, and fully transparent, and it only gets worse as the economy gets worse, as the government wants an accounting for every last penny, because they believe the public really will care on which toilet paper is being used by government officials. Also if something is not on a standing offer for the government, it must go to be bid on by businesses.
The thrust to weight ratio of the rocket motor only really matters near the end of a burn when the motor weight becomes a significant part of the total vehicle mass at that time after hundreds of tonnes of fuel and propellant have been expended. It's a good thing to have a lightweight motor but shaving a hundred kilos off the motor mass isn't as important as boosting the Isp by, say, ten seconds as that boost improves the performance all the way through the burn and has a much bigger impact on payload to orbit with given hardware. SpaceX have been working hard to improve Isp, of course -- the Merlin first-stage 1D motors are a lot better than the original flight motors they started their operations with and they now have optimised upper-stage versions of the 1D for vacuum with improved Isp figures.
I know other manufacturers have looked at methane-oxygen engines in the past but not progressed with them. Why they didn't I'm not sure. LOX/RP-1 has a good track record and decades of actual operation to work with (which SpaceX took advantage of), LOX/CH4 is more of a leap in the dark. Building a big LOX/CH4 motor as the first flight item is another big step and obviates the cheap multi-motor Falcon vehicle platform SpaceX have been developing over the past few years.
of course I've heard of peak oil, but if you're going to post your tripe, at least do a decent job of informing people of what you're trying to say instead of a bunch of chicken little hornblowing.
RD-180 flew it's first flight in 2000, and it's based on RD-170 which flew it's first flight in 1987.
So not designed in seventies.
AK-26 / NK-33 (used in Antares rocket) is the engine developed in sixties and manufactured in seventies.
RD-170 is more powerful than F-1. Though it's multi-chamber engine.
Space shuttle solid boosters are also much more powerful than both F-1 and RD-170.
F-1 is the most powerful single-chamber liquid-fuel engine.
Space elevators would be pretty nice, but we still haven't found a material strong enough
That is only true for Konstantin Tsiolkovsky's 1895 space elevator design, which is seriously out of date. A segmented elevator is perfectly feasible with current carbon fiber. This uses a small one in low orbit, and another small one in GEO. You use orbit mechanics to transfer from one to the other. The combined cable length is 50 times less than the original version. That makes it more economical, less exposed to impact damage, and able to be built incrementally.
Unfortunately, the only pictures you see in media articles are of the 1895 concept, so that's the one people always think of. We need to get public perception out of the 19th century.
or some other boringly predictable rant.
Argh - I forgot that one. I do understand though, that the faith based physics rocket launchsite hereafter known as the "Palindrome" will be based at the Cliven Bundy Ranch.
It will consist of approximately 500 million Estes rockets inside a drainpipe all timed to go off at once. Coupled with a lot of prayer, this should go like gangbusters.
The first test pilot will be Mitt Romney's dog - the one that traveled on top of his station wagon.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
The shuttle had several very near accidents in its run.
NASAs current criteria for man-rating would - for astronauts that fly six times a year be safer at work than:
A) Deep sea fishermen
B) Lumberjacks
C) Librarians.
Hint: It's not the first two.
(actual figures from US statistics).
Dou! The thing is if you want to put all this stuff into orbit -self running autonomous factories and so on - the first thing you will need is a bigger rocket - a much much bigger rocket. (like 100 or 500 tons to GEO or more) What we really need for the expansion into space whichever way we do it is a rebuild and reimagining of something like the old 'Sea Dragon' project. If you want to move a lot of cargo (or hundreds of passengers) you need to build big.. Its Simple!!!
Below the speed of light Special Relativity is one of the most accurate theories in physics - above the speed of light..
Let me be the first to let you in on a secret... Rocket science is hard. Last time I checked, the Falcon9 is racking up an impressive reliability record. Yeah, he wants to launch lots of them... which would you rather have, a ramshackle build an launch as fast as you can damn the torpedoes, oh well if a couple blow up or a systematic engineering driven approach to build a simple, ultra reliable, reuseable launch system.
I don't know of a single launch system that's <i>ever</i> been on time. When managers sit down with powerpoint and make up launch schedules and total tons lofted, they're just blowing smoke.
The only evidence they've provided is the fact that they've been modifying the stannis testing facility to test their mega rocket engine. Oh and that they've been building parts and testing them... you know doing engineering things.
This is a natural progression. They started with the Falcon1, then the Falcon9, now this. Yeah, it's going to be a long road, but Musk has proven himself capable of getting shit done. Not at your unrealistic speed.
Do I think SpaceX will launch a HLV? Yes. Will it be on schedule. Yes, because SpaceX won't commit to a schedule until they've got something tested. Will it require some serious engineering? Yes.
Now, how will this effect the thing Nasa is working on? Who knows. I wish NASA would get out of the business of launching things and focus more on the things being launched.
Yes Francis, the world has gone crazy.
Even more motivation to defund SLS...
one failure in 13 launches.