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Elon Musk Talks "X-Wing" Fins For Reusable Rockets, Seafaring Spaceport Drones
An anonymous reader writes Elon Musk sent a number of tweets recently in which he detailed a program to test the function of "X-Wing" style grid fins that could help spacecraft navigate upon re-entry. The tweets describing how it would work, also include an autonomous seafaring platform, which can hold its position within three meters even in a heavy storm, that would act as a landing pad. From the article: "The SpaceX reusable rocket program has been progressing with varying results, including an explosion over Texas back in August. While the incident didn't result in any injury or even 'near injuries,' Musk conceded in a tweet that this was evidence that '[r]ockets are tricky.' An earlier test flight from this summer involving an ocean splashdown was considered more successful, proving that the Space X Falcon 9 booster could re-enter earth's atmosphere, restart its engines, deploy its landing legs and make a touch down at 'near zero velocity.'"
I've seen these already in use on bombs and other ordnance from several factions.
Seven puppies were harmed during the making of this post.
I have not seen any evidence that the second stage has ever been designed to soft land.
There are SpaceX videos showing it doing just that, though the big saving comes from reusing the first stage, which has nine times as many engines as the second stage. If you can reuse the first stage ten times, then reusing the second starts to make sense, because it would make up around half the cost of a launch.
Any Dragon capsule will still splash down in the ocean.
For now. Again, the plan appears to be to switch to a powered landing on land, as the same engines can then be used for launch abort, in-flight maneuver, and landing.
There is a great interview with Elon Musk on youtube here. He is remarkably transparent about his reasoning. One key to his success is that he works very hard to understand motive and purpose when making decisions.
Musk makes that point that it costs about as much to fuel a rocket as it does to fuel a 747. Space launches are mostly so expensive because the vehicle is sacrificed with each launch, not because of the energy requirements for a space launch. The other big component of the expense is that rocket manufacturers charge a lot. According to Musk the value of the raw materials from which they are formed is reasonably inexpensive. Those were two hugely important realizations because they meant that space launches were not inherently expensive and therefore there is enormous potential for reducing launch costs.
By being Space X instead of Boeing the cost of launch is reduced to about 25% of conventional launches because Space X can assemble a rocket from raw materials for that much less. A re-usable vehicle, Musk predicts, would reduce launch costs by an order of magnitude.
So those are the motives and reasoning underlying the X-wing grid fins and re-entry discussed in the Slashdot summary.
Ceci n'est pas une signature.
It is not NASA's fault. It is congress going after pork. The scientists at NASA are pretty damn good and generally know what they want. Often it is a choice between something misguided like SLS or nothing at all. It is not as if NASA scientists or administrators would have picked SLS the way it is. They were pretty much told, if you don't build it using these suppliers we are not going to fund you.
I should mod you down, but I have to speak up.
First off, Musk had this in mind back in 2002 when he started this. IOW, he has 12 years into it.
Secondly, Musk HAS SPENT BILLIONS on this. Some of his money. Some of others. Some of NASA. Some of future contracts. All in all, he has spent billions to get to this point.
Third, NASA builds prototypes, but all of the rest is done by private companies, otherwise known as PRIVATE SPACE.
Chad, what I find interesting is that ALL OF NEW PRIVATE SPACE will tell you that they NEED NASA. Why? Because NASA knows this stuff inside and out. Heck, Elon did F1 on his own all the way through to his first launch. Remember how that turned out? SPECTACULAR.
After that, he swallowed his pride and worked closely with NASA and their QA. And while F1 underwent a re-design, what really changed was that SpaceX learned how to do decent QA. They put into place repeatable processes.
So, while you can continue to knock SpaceX, bear in mind that Musk, top ppl from SpaceX, Bigelow, top ppl from BA, Bezos, top ppl from BO, Ozmen, top ppl of SNC, will all tell you that they cound heavily on NASA. And they will tell you that they count on NASA for experience and help far more, than on their money.
It is long past time to put aside your politics and focus on facts.
I prefer the "u" in honour as it seems to be missing these days.
I am not an aerospace engineer but there is an obvious advantage; drag. Normally drag is a bad thing but when you are trying to slow the decent of an object drag is a very good thing. The more drag they can produce the easier it will be to slow the decent.
No. Its not NASA, its Boeing, Lockheed Martin, et al.
When people talk about the "privatization of space" I generally laugh. Spacecraft where always made by private industry, and always operated by the government, so far nothing has changed.
Why else did the space shuttler look like an airplane? Thats not a practicle design for space. Its because it was made by boeing.
Its just that SpaceX is not a defense contractor.
No, the big difference is how the contracts are written, how the winners are selected, and how much design influence NASA and Congress exert (yes Congress).
Historically, NASA was heavily involved in the design and many decisions were forced on them by Congress to direct the money to specific congressional districts (remember those segmented solid boosters on the Shuttle? You can thank Congress for them. And they are going to use them again on the next generation SLS which is not a commercial contract.) Historically, once NASA/Congress have doled out the contracts, the work was performed on a cost plus basis. The contractors had very little financial risk, and NASA/Congress had a lot of control over the process.
The way a commercial contract works is that the companies bidding on the contracts are given requirements and they have much more freedom in how they meet those requirements. They respond with a proposal as to how they intend to provide a solution and a fixed cost. SpaceX builds almost everything in house, Orbital Sciences outsources almost everything in their rocket. Both choose exactly how they wanted to meet the requirements and NASA/Congress had no control over them which allowed them to take very different approaches.
Ideally, more than one company wins a commercial contract (SpaceX and Orbital for cargo, SpaceX and Boeing for crew). This provides redundancy in case there is a failure, unlike when the shuttle failed and our entire manned space program was grounded for years. Twice. It also allows for more competition to put some downward pressure on prices and allows for new entrants for future contracts.
Now system is perfect, but the commercial cargo/crew program is absolutely better than how we used to handle "routine" space requirements.
Some privacy policy Slashdot.
Your point is well made, but I think it's a case of semantics. Elon had "enough" resources to get the job done, with help from others. If he hadn't put $100M of his own money into SpaceX nobody else would have put in $100K, let alone the millions more it took to get where they are today. The fact that even Elon occasionally needs help from others doesn't strike me as a particularly important criticism.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
No, the 'x wings' are not passive, but they are just as steerable as normal fins. See this video of SpaceX where they used them for roll control on a test flight in Texas. And the software to control these is pretty standard.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]