Slashdot Mirror


User: Teancum

Teancum's activity in the archive.

Stories
0
Comments
6,606
First seen
Last seen
Profile
(view on slashdot.org)

Comments · 6,606

  1. Re: A bit off topic on SpaceX Rocket Launch Succeeds, But Landing Test Doesn't · · Score: 1

    The extra margin and engine-out capability is not a requirement

    On the contrary. It is a requirement as per NASA contracts, but also standard practice in the rocket industry. It is called reserve fuel. Look it up. Every successful launcher that has put things into orbit has such a reserve fuel load that never gets used except in emergency conditions.

    SpaceX is merely taking advantage of that reserve fuel after the 2nd stage has been lit up to be able to do something useful with the 1st stage. The engine-out capability is something that has been used by other rocket designers as well, including something Werner Von Braun used in his design of the Saturn V.... something that even made a couple Apollo flights successful that would have failed had that capability not been there.

    You don't plan on using the reserve fuel in a nominal flight to boost performance. SpaceX did launch a geosynchronous orbit satellite that pushed the reserve fuel load to the point that testing of the 1st stage landing procedures didn't happen, but it still had the reserve fuel left in the 1st stage after stage separation. It was later said that SpaceX did test the landing process anyway on that flight, but it was rather low-key and didn't involve a hover test.

  2. Re:A bit off topic on SpaceX Rocket Launch Succeeds, But Landing Test Doesn't · · Score: 1

    The Space Shuttle was designed to land at the Vandenberg Air Force Base

    Was there a Shuttle landing strip at VAFB? An air strip that could bring the Shuttle on the 747 carrier certainly existed and was even used on a couple occasions (when the Enterprise showed up there for some fitting tests), but I don't think it was ever intended to land there.

    On the other hand, Vandenberg was to be a launch site for polar launches with an emphasis on military payloads that never ended up being used with the Shuttle. I'm pretty sure any such landings were to happen at Edwards AFB, but I might be wrong on that issue.

    The big change to the Shuttle was the cross-range requirement where it could potentially evade Soviet (at the time) tracking and be able to do a single orbit mission to put a military payload into orbit and land immediately after deployment. Such a flight would require significant turning since over the course of the mission a straight wing would have put the Shuttle over the middle of the Pacific Ocean (when launched from Vandenberg). Again, no such mission ever actually happened, but it was one of the things that adversely impacted the shuttle design since it was designed to fly such a mission.

  3. Re: Minor setback on SpaceX Rocket Launch Succeeds, But Landing Test Doesn't · · Score: 1

    The space shuttle fuel tank was not quite in orbit yet, so it would have taken extra fuel to get it there.

    The extra fuel was in the tank anyway as reserve fuel. The only reason why it was jettisoned before full orbit had to do with trying to keep it from cluttering up LEO with more space debris, so hanging onto the tank would have been trivial by comparison. It would have required a slight design change in the tank construction to make it useful though, and likely some in-orbit construction in order to make the tanks useful on a practical level, but neither the fuel nor applications were a problem. It was mainly an issue of getting a very conservative thinking congress (on space issues) to agree to funding any mission that would use the tank.

    At this point, it is a moot idea since the Shuttle program is no more, but it was an interesting idea that could have been utilizing a resource that otherwise was discarded.

  4. Re:Minor setback on SpaceX Rocket Launch Succeeds, But Landing Test Doesn't · · Score: 1

    There has to be a test range on land somewhere they can try putting one down instead of a pitching platform in the middle of the ocean.

    There is such a test range. It is called "Spaceport America", the same place where Virgin Galactic is doing their test flights and planning on providing regular service for the Spaceship Two. In this case, SpaceX is using the facility for a vertical launch due to the high altitude flight restrictions of the area (in part due to the White Sands Missile Range next to this spaceport in New Mexico). It isn't to get the rocket to orbit, but they do plan on testing landing procedures in a repeated fashion and in a way that doesn't tie up the Florida launch site either.

    SpaceX has also done some extensive testing at their McGregor, Texas facility where they perform primarily the engine tests. You can see these tests on YouTube, including watching the cows go into a panic with the rocket sounds on a nearby ranch. The problem with the Texas facility is that the FAA hasn't given SpaceX the clearance they need to test at higher altitudes...which is why they are moving the tests to New Mexico.

    More tests are planned this year, so expect to see some more posts about the vehicle in coming months. This particular test done today happened mainly because they were going to ditch the stage in the ocean otherwise, so they might as well try to get some engineering data to help refine the process under full flight conditions. SpaceX has been using this strategy as well for the past several launches, including some tests that had the rocket hover over the ocean prior to engine shutdown.

  5. Re:Minor setback on SpaceX Rocket Launch Succeeds, But Landing Test Doesn't · · Score: 1

    It would be hugely valuable if simply some engines were recovered in some form at all, and send to McGregor for disassembly and engineering review. In other words, if just one engine landed on the deck in a couple of salvageable pieces (not even flight worthy.... just enough to examine), it will still be a valuable exercise.

    It is now looking like SpaceX underestimated the amount of hydraulic fluid needed to keep the grid fins operational at the end of the flight. A small detail sort of like the nut that destroyed Falcon 1 Flight 1 as well as some of the other early Falcon 1 flights that had other correctable but significant flaws that kept the flight from being perfect.

  6. Re: No good video? on SpaceX Rocket Launch Succeeds, But Landing Test Doesn't · · Score: 1

    Specifically it was the hydraulics on the grid fins that ran out of fluid about a half minute before landing. It will be a few days before more details come out about the position of those fins and how those final seconds might have been impacted, but some attitude control was likely lost along with some braking force as the grid fins do provide some additional drag that might not have been compensated for when that hydraulic system drop out of active control.

    It has been said that the rocket hit landed hard.... whatever that might actually mean in terms of velocity.

  7. Re:What's with the "robber" nonsense? on The Billionaires' Space Club · · Score: 1

    The prices did drop to less than 5% of what he was originally charging. Actually more like less than 1% of the original prices.

  8. Re:What the hell is this guy smoking on The Billionaires' Space Club · · Score: 2

    This is a technology that only only a number of countries you can count on your fingers can do.

    I think you can put that on a single digit. The Soyuz spacecraft can basically return the three member crew and essentially a postage stamp. Well, it is about a hundred pounds of extra baggage, but essentially nothing on a practical level. The Dragon spacecraft really is the only vehicle currently in active use that has this capability at all.

    Yes, Russia obviously has the capability and even flew the Buran spacecraft that had some capability of returning stuff from orbit. The Chinese Shenzhou spacecraft has the same return capabilities of the Soyuz (basically nothing) although I have no doubt that if China needed the capability they could make it. There is also the X-37 spacecraft that the USAF has been playing with that may or may not have actually brought stuff back from orbit. It also should go without saying that the Boeing CST-100 as well as the Orion capsule should also be capable of returning more substantial amounts of cargo from space (Boeing is even trying to muscle their way into the next round of the commercial cargo resupply flights). ESA has never had a return cargo capability of any kind, nor has Japan even though I don't doubt either "country" (is the EU a country?) could put up such a spacecraft if they cared. Both Japan and ESA have sent cargo flights to the ISS though.

  9. Re:What the hell is this guy smoking on The Billionaires' Space Club · · Score: 3, Informative

    I'm suggesting that some of the methods that SpaceX has employed to reduce costs of their rocket in terms of applying mass production techniques and treating the manufacturing of rockets more like how automobiles are manufactured on an assembly line has made a huge impact in terms of the cost of a launch. They are currently manufacturing more than a couple Merlin 1-D engines each week and plan to ramp up that production rate to even higher levels. They have also streamlined a number of things in the vehicle design to drop prices considerably including using consumer grade electronics instead of mil-spec equipment (using redundancy instead to achieve higher reliability) and several other innovations to really drop costs that haven't been used earlier.

    That is the cake I'm talking about which other companies haven't been able to achieve... for various reasons. The Merlin 1-D engines aren't the highest performing engines and definitely have some strong limitations, but they are very cheap to manufacture. The same goes for the body of the rocket and other parts too. The vertical integration of SpaceX has also helped in terms of keeping the supply chain tight and keeping costs under control.

    I also question how much actual savings will happen with reuse as there are definitely fixed costs that really limit how much it can reduce costs. 1st stage reuse at best only saves about half of the cost.... when done over the course of nearly 20-30 launches for amortization and assuming even low fixed costs. That still is useful and can make SpaceX very competitive, but it isn't nearly the earth shattering cost reduction that some are suggesting. SpaceX isn't even talking much any more about 2nd stage reuse, and all of the contracts using the Dragon spacecraft currently require a new capsule on every launch.

    In other words, SpaceX really can't be depending on reuse for profit and instead must depend on other ways to cut costs in order to survive as a company while charging so little to the end customers. Admittedly, SpaceX officials have quoted a price point of $7 million per launch of the Falcon 9 to deliver 10 metric tons to LEO as something they are aiming at (mentioned at a satellite conference in Indonesia last year with commentary by other launch providers simply saying SpaceX is quoting nonsense). That is about 1/10th of the price currently, but I would assume that includes more than just reuse savings.

  10. Re:What the hell is this guy smoking on The Billionaires' Space Club · · Score: 2

    SpaceX is making a profit off of their expendable rocket program.... and beating the Chinese Space Agency on a cost per kilogram into orbit even doing just that. Mind you, the main way that SpaceX is going to try to get launch prices cheaper is simply to reuse the first stage by flying it back to the launch pad... something that won't ever make the trip into space anyway. Most of the fuel that the stage will be firing is the reserve fuel that normally isn't used in a nominal flight but will be used in an attempt to recover the stage after it has accomplished the primary task of sending the rest of the rocket to a point it can get into orbit and space.

    Another difference between what SpaceX is doing and previous attempts is that they are doing it incrementally instead of all at once (a huge problem for Rotary Rocket as well as the DC-X and arguably even the Space Shuttle) and it isn't being done with tax dollars but rather with private R&D spending. They don't depend upon a vague and indifferent Congress to decide if funding for the R&D program will continue or not. No NASA money is being spent on the reusable engine program but instead is simply minor testing after the revenue portion of the flight has already happened.

    We will see next month (or this month... depending on when you read this) how successful SpaceX will actually be with the concept, since they are attempting to capture and successfully land the first stage as a part of the next launch. If it was power point presentations still, your argument that this is bullshit would be justified. Bent hardware currently sitting on a launch pad (SLC-40) in Florida awaiting FAA-AST approval for launch doesn't sound like bullshit to me. I think SpaceX is in slightly better shape than you think.

  11. Re:What the hell is this guy smoking on The Billionaires' Space Club · · Score: 1

    More important, what Elon Musk has provided for spaceflight is a huge reduction in cost that can be measured as dollars per kilogram to orbit. The Space Shuttle typically got somewhere in the range of about $20k-$40k/kg to LEO (depending on how you calculated the cost of launching a shuttle.... getting the order of magnitude on that number is dubious at best and no two independent sources give the same number). Typical in the launch industry is about $10k/kg as a general rule of thumb (if you can get cheaper... it is likely a good price for a launch). SpaceX on the other hand has a posted price for a Falcon 9 (no frills or extras where the customer has to do everything else once they get into orbit) of about $60 million per launch. @10,000 kilograms for the payload capacity of that rocket (officially rated for about 15 MT, but I'm being generous here and deliberately low-balling the price) that gives you a price of $6k/kg.

    In other words, the bottom line really does matter, and SpaceX is extremely competitive and cost effective for getting into space.

  12. Re:Uninformed Drek disguised as Journalism on The Billionaires' Space Club · · Score: 1

    The value of SpaceX as a corporation would largely be due to the nearly cult-like personality of Elon Musk and a whole bunch of people trying to get a piece of the action that he is doing with the company, not so much what is on the books for launch contracts.... which would barely be about $2 billion (being generous including NASA and DOD/intelligence contracts that are a matter of public record). They only had six launches this year (still pretty good), and being very generous with $100 million per launch that means they only had a revenue stream of just a little over a half billion this year and a huge amount of spending that they've done too. That isn't profit, just revenue in an industry with a fairly tight profit margin and SpaceX being the discount competitor still trying to get customers by offering steeply lower prices.

    Mind you, the future of the company does indeed look bright and accounting practices do include future launches in terms of company profits, but a couple of bad launches like what happened to Orbital or Sea Launch could spell disaster to the company and really cause the value of the company to drop considerably and even cause customers to flee. I wish SpaceX all the best and I hope they can continue their success with future flights, but nothing is guaranteed in this industry. It is after all called rocket science.

  13. Re:What's with the "robber" nonsense? on The Billionaires' Space Club · · Score: 1

    Then he used some rather extreme tactics to preserve his lead, none of which benefited consumers.

    Other than the fact that between when Rockefeller started providing products for his customers and when he finally called himself a billionaire, he was selling the same product for less than 10% of what he was originally charging. I suppose that didn't help the consumer in any manner?

    I'm not saying he was a saint and that there was no room for criticism, but you are also flat out wrong that his actions didn't help the buyers of the products he was selling. That he clearly stopped other potential competitors from entering the marketplace is true, but he also was hardly the only person to shut out subsequent potential competitors from entering into an industry either. Sadly, most business regulations and laws are designed explicitly to encourage that kind of behavior too.

  14. Re:What's with the "robber" nonsense? on The Billionaires' Space Club · · Score: 1

    You are talking about a very short period of prosperity that was artificially created by having the government dump a whole pile of money largely created by debt extending barely over a twenty year period of time. It was also something largely not true anyway even at the time where it wasn't as widespread of a practice as you are claiming either... certainly not for smaller businesses including mom & pop retail outlets.

    It is a dream world that never existed that you are pining for and expecting conditions to duplicate once again. Once again I'll point out that it is these same "Robber-Barons" that created the conditions that made such long-term contracts even happen in the first place. It is indeed called capitalism!

  15. Re:What's with the "robber" nonsense? on The Billionaires' Space Club · · Score: 3

    They robbed the workforce of long term employment stability in exchange for trinkets.

    When in history did anybody ever have long-term employment? It was the so-called Robber-Barons that provided such long term stable employment contracts to their workers in exchange for loyalty. Prior to the Industrial Revolution, they were instead plundered by knights as they pillaged farmland and took random women as mistresses and whores (often involuntarily... and legally). Or you can go back to your hunter-gatherer tribe.

  16. Uninformed Drek disguised as Journalism on The Billionaires' Space Club · · Score: 1

    Neither article is well researched and the "Billionaire Space Club" in Slateis particularly awful in terms of even pulling out legitimate statistics other than from the author's hind end. In the rare instance (like his quote of $35 million for space tourists on the Soyuz spacecraft) that he seems to get something close to reality, it is so dated and obsolete that he might has well be making up that figure too. I have no idea where the "$20,000 per pound to take cargo into orbit" figure came from as that is perhaps a generic industry rule of thumb price yardstick, but still not anything close to reality.

    It is possible to make the general argument being made here that perhaps Elon Musk and Jeff Bezos are milking taxpayers for billions of dollars in a manner that is unjustified. You can quote the multi-billion dollar awards given explicitly to SpaceX and millions of dollars of help given to Bezos with his Blue Origin company too as unneeded extravagance. On the other hand, quote the exact awards (like the SpaceX COTS and CCtCAP contracts) or go into how Blue Origin has acquired the DC-X research at basically pennies on the dollar including hardware and test facilities. Blue Origin is still receiving assistance from NASA in the form of consultants and technical data for their ongoing R&D efforts.

    Hell, he didn't even get that Orbital Science has been purchased by ATK... a major defense contractor... and instead treats them as the tiny underdog being bulldozed by SpaceX.

    The author made none of those assertions, thus shows simultaneously arrogance and ignorance. A rather dangerous combination if anybody took him seriously.

  17. Re:What the hell is this guy smoking on The Billionaires' Space Club · · Score: 4, Interesting

    Ariannespace already treats SpaceX as a credible threat and is making significant changes to their next generation Ariane launch vehicle specifically to go in a direct competition with the Falcon 9. I don't know if they are going to succeed in being able to drop launch costs below $1k/kg like Elon Musk seems to be striving for, but they sure want to stay in the game and try to at least maintain market share against SpaceX and the stream of steady launch contracts that are now going to America that used to not happen.

    SpaceX is definitely winning more launch contracts than they are currently launching, so I expect that even an increased launch rate is going to be sustainable for that company into the near future. This is even without the reusable launchers that SpaceX is trying to develop as I consider that to be merely icing on the cake and a long term extra profit thing even if the upcoming launch pancakes the 1st stage after stage separation.

    ULA is merely trying to compete against SpaceX in the halls of Congress instead with lobbyists. I wonder how that will work out in the long run?

  18. Re:Extended Range on Tesla Roadster Update Extends Range · · Score: 2

    Lotus also retooled the production line that Tesla was using, which is another thing that killed the Roadster. Lotus didn't have a problem with Tesla continuing their relationship (well, sort of), but that would have also required some additional engineering effort to retool the customized components that Tesla was using.

    In short, like you said... it would require a whole new redesign from basically a clean sheet of paper that only superficially looks like the original Roadster. The battery technology would still be largely the same, but even that has evolved over the years.

  19. Re:Stupid/Misleading Title on US Navy Sells 'Top Gun' Aircraft Carrier For One Penny · · Score: 1

    Even if it was sold for a penny, there may still be contract restriction on resale as well as criminal and civil restrictions on what other things they can do with such things. North Korea in particular is banned from the sale of munitions (including computer software in some cases), so I think ITAR would definitely apply to a used but functional aircraft carrier. At the very least, a "right of first refusal" clause could be put into any sales contract where the DOD would need to be offered and informed about any resale in anything close to its current form. Historical easements might also be applied by the various historical organizations that could further complicate any resale or even use by anybody except for demolition without having those easements being cleared.

    I would agree with you that turning it from a sale into a contract does make some legal distinction though, as it can mean that the DOD would be required to address issues like asbestos found in compartments that weren't documented, classified documents that weren't properly removed before the contract, and a few other minor issue of mainly liability that the Department of Defense would need to address in a demolitions contract that instead would need to be held by the company doing the demolition work.

  20. Re:Does he stand a chance? on 'Citizenfour' Producers Sued Over Edward Snowden Leaks · · Score: 1

    One thing you can do in many states is to get an initiative or referendum started that can take the issue directly to the voters. My experience in such matters is that when such ground rule changing questions get on a ballot (with enough publicity and other factors too), the voter turnout is usually quite strong. I also find that the voters tend to get the issues involved.

    Getting the rules for how people get elected, with single alternative vote, instant run-off, or some other voting system will go a long, long way to fixing the system. It can happen, and I've even participated in getting such things done including forcing the state legislature where I live to pass a law instead of waiting for the results of the referendum to be counted. No, I wasn't just a signature gatherer but somebody who was organizing the whole thing. I've been involved in three such petition drives and know a little bit about how to get stuff like that done for a relatively small cost (in the mere thousands of dollars range, not millions, for a state-wide effort).

    The question that needs to be asked is how much do you really want to see a change, or are you merely going to cast your lone 3rd party vote and think that will make a difference?

  21. Re:Does he stand a chance? on 'Citizenfour' Producers Sued Over Edward Snowden Leaks · · Score: 1

    I'm not advocating or asking to have explained why documents should remain classified. What I'm complaining about is why federal agents whose job is to process information are being explicitly told they can't learn about classified information from a public source like a newspaper or a blog when ordinary citizens are capable of obtaining that information? It is this duplicity that I'm complaining about which makes federal agents have less knowledge about stuff happening than ordinary citizens... in some situations.

    If some CIA analyst can pick up the Washington Post and read the same newspaper that is dropped onto the desk of Kim Jong Un, why should he go through some mickey mouse bullshit to declassify that same newspaper article?

  22. Re:Does he stand a chance? on 'Citizenfour' Producers Sued Over Edward Snowden Leaks · · Score: 1

    I would suggest you watch the video I referenced. It explains not only why you have two parties, but also why the vast majority of people don't want to bother voting either. At a recent municipal election that I participated in, my city had an abysmal 5% voter turnout. I have to presume it is because the other 95% of the registered voters didn't feel it was worth their effort in spite of the fact that over half of the taxes they pay go to those municipal officials. That was a non-partisan election too! (aka no party affiliation was permitted on the ballot.... candidates ran strictly on their own name alone).

  23. Re:Does he stand a chance? on 'Citizenfour' Producers Sued Over Edward Snowden Leaks · · Score: 1

    If you want to make a difference and change what is happening, you need to change the way voting takes place, not just simply throw your vote away by voting for a 3rd party. You had better believe that it takes action, but merely voting "present" isn't going to matter.

    Study up on alternative voting systems, and when you get the opportunity make sure that you encourage something other than First Past the Post voting happens. I convinced the members of my local voting precinct to change to Instant Run-off voting instead. Yes, there are other voting systems, but almost anything is better than First Past the Post. That was just for minor stuff, but you need to give ordinary people the experience of voting in some other manner, even if it is just for class president or who is going to be stuck going on a beer run at midnight.

    It is much more than just money in the system, it is noting that the entire system for voting is broken in a critical way.

  24. Re:prior oath to defend the Constitution on 'Citizenfour' Producers Sued Over Edward Snowden Leaks · · Score: 1

    The contracts specifically reference parts of the U.S. Code noting that penalties involved for violating what happens under such contracts can be prosecuted under federal law. So yes, these contracts do override specific laws.

    Drug cartels can also write up such contracts, but I doubt you will get them to have a federal judge be the enforcement and interpretation arm of those cartels. That is the difference. On the other hand, if you work for IBM or some other private company (with damn good lawyers writing up employment contracts), you similarly don't want to violate the terms of your contract as you will end up in front of a federal or state judge where you can be prosecuted for violating trade secret laws criminally as well as HUGE civil penalties that would trash your life fiscally.

    There is a reason why NDAs are effective. I also wouldn't want to screw with an NDA given to you by a drug cartel as that might end up with a horse head laying next to you instead.

  25. Re:Does he stand a chance? on 'Citizenfour' Producers Sued Over Edward Snowden Leaks · · Score: 1

    There should be an common sense exception for things in the public domain but these rules were created before the internet existed and foreign powers didn't indiscriminately share everything.

    This is a cop-out excuse. The duplication of information has been a problem since Gutenberg developed the printing press and enabled the mass dissemination of knowledge. To claim this is a new phenomena and something that needs common sense rules simply goes to show how silly such rules are in the first place.

    There is a good reason why the 1st Amendment exists in the U.S. Constitution, and specifically mentions printing presses (something the authors of the U.S. Constitution knew about). The 1st Congress also passed laws about official state secrets, including their applicability with activities related to the War Department. The damage that a faithless traitor could make was also seen in the form of Benedict Arnold, whose damage of the American Revolution still can't be completely determined, and was made very apparent at the beginning of the USA to those making such rules.