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Thread: SpaceX Omnibus Thread

  1. #31
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    This is so wicked pissa!!! Seriously, a huge game changer.

    We've seen Bezos and now Musk succeed. There are others also getting involved. This is bringing me back to my youth in the 1960s when the teacher wheeled the TV into the classroom so we could watch the live launches and landings. It was an amazingly exciting time and we all wanted to be astronauts or work for NASA.

    Perhaps this will be the spark that helps ignite this generation and steer them towards the stars.

    Congrats again, all.
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  2. #32
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    technologically speaking this is very impressive-- imagine if airplane engines had to be thrown out every time they were used.

    now if we could move off chemical rockets...
    There is a cult of ignorance in the United States, and there has always been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that "My ignorance is just as good as your knowledge."- Isaac Asimov

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    I'd be more impressed with the whole thing if that first stage on the Falcon did more than just lift the actual rocket on top of it out of the atmosphere, basically bypassing Max-Q for the stack. A Falcon only does Mach 6 at 90 km altitude when the first stage separates.

    For comparison, on an Ariane 5 the boosters do that job to exactly the Mach 6 point at only 60 km altitude, and the first stage then pushes the stack to around Mach 17 at 110 km. The boosters on Ariane 5 can be equipped with a recovery kit that slows their splashdown speed from Mach 6 to Mach 0.08 - which is used occasionally to do post-flight analysis, especially after production changes. The boosters land fully intact and float in the water until someone tows them the 500 miles back to Kourou. Refurbishing to launch-ready state was originally considered but rejected as too cost-intensive.

    In other words: We'll see when a landed Falcon stage flies again. This one won't, btw. And we'll see if such a launch will be cheaper for the customer. Especially once the likely much higher insurance premium for launching on a second-hand stage comes into play.

  4. #34
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    Quote Originally Posted by kato View Post
    I'd be more impressed with the whole thing if that first stage on the Falcon did more than just lift the actual rocket on top of it out of the atmosphere, basically bypassing Max-Q for the stack. A Falcon only does Mach 6 at 90 km altitude when the first stage separates.

    For comparison, on an Ariane 5 the boosters do that job to exactly the Mach 6 point at only 60 km altitude, and the first stage then pushes the stack to around Mach 17 at 110 km. The boosters on Ariane 5 can be equipped with a recovery kit that slows their splashdown speed from Mach 6 to Mach 0.08 - which is used occasionally to do post-flight analysis, especially after production changes. The boosters land fully intact and float in the water until someone tows them the 500 miles back to Kourou. Refurbishing to launch-ready state was originally considered but rejected as too cost-intensive.

    In other words: We'll see when a landed Falcon stage flies again. This one won't, btw. And we'll see if such a launch will be cheaper for the customer. Especially once the likely much higher insurance premium for launching on a second-hand stage comes into play.
    I'd be more impressed if your comparison makes some sense, but it didn't. its actually laughable.

    is ariane made by private enterprise? can its booster land vertically back to earth? then whats the point of the comparison?
    Last edited by drhuy; 30 Dec 15, at 19:22.

  5. #35
    Official Thread Jacker Senior Contributor gunnut's Avatar
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    Quote Originally Posted by kato View Post
    I'd be more impressed with the whole thing if that first stage on the Falcon did more than just lift the actual rocket on top of it out of the atmosphere, basically bypassing Max-Q for the stack. A Falcon only does Mach 6 at 90 km altitude when the first stage separates.

    For comparison, on an Ariane 5 the boosters do that job to exactly the Mach 6 point at only 60 km altitude, and the first stage then pushes the stack to around Mach 17 at 110 km. The boosters on Ariane 5 can be equipped with a recovery kit that slows their splashdown speed from Mach 6 to Mach 0.08 - which is used occasionally to do post-flight analysis, especially after production changes. The boosters land fully intact and float in the water until someone tows them the 500 miles back to Kourou. Refurbishing to launch-ready state was originally considered but rejected as too cost-intensive.

    In other words: We'll see when a landed Falcon stage flies again. This one won't, btw. And we'll see if such a launch will be cheaper for the customer. Especially once the likely much higher insurance premium for launching on a second-hand stage comes into play.
    Perfect example of when NOT to recycle.
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  6. #36
    Senior Contributor SteveDaPirate's Avatar
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    Quote Originally Posted by kato View Post
    I'd be more impressed with the whole thing if that first stage on the Falcon did more than just lift the actual rocket on top of it out of the atmosphere, basically bypassing Max-Q for the stack. A Falcon only does Mach 6 at 90 km altitude when the first stage separates.
    A big part of what makes it impressive is the fact that after stage separation, the first stage flips around to kill its velocity and burn back to the point of origin. Landing 500 miles downrange under parachutes would obviously be a lot more straightforward to accomplish, but as you pointed out, recovery and transportation are expensive and cut into the benefits of reuse.

    Additionally, recovery and refurbishment of boosters offers much less financial incentive than the recovery of complex liquid fueled engines.

    Quote Originally Posted by kato View Post
    In other words: We'll see when a landed Falcon stage flies again. This one won't, btw. And we'll see if such a launch will be cheaper for the customer. Especially once the likely much higher insurance premium for launching on a second-hand stage comes into play.
    I expect the first couple successful recoveries will be cannibalized and studied, but I believe that the Merlin engines were designed from the outset to be refurbished and flown again. Watching the trajectory of launch prices once refurbished rockets begin flying regularly should give us a better indication of how successful they were at designing engines that can be recertified.

    As far as insurance with regard to a second-hand stage is concerned, that calculation will likely depend on the launch customer. A commercial business launching a fleet of small satellites would probably be willing to accept a slight increase in risk if the reduction in price makes it worthwhile since they are basically just doing a cost/benefit analysis.

    A government launching a satellite with national security implications or manned mission will probably still prefer to fly on whatever platform gives them the highest probability of a successful launch, and damn the price.

    Regardless, it seems like the entry of SpaceX has breathed some new life into the satellite launching business. Ariane 6 is apparently being designed to be more economical, particularly for smaller payloads, to compete with expected budget prices offered by SpaceX. This includes investment in the development of an Airbus proposal to return the first stage engines (but not the whole stage) to the launch area for refurbishment.
    Last edited by SteveDaPirate; 30 Dec 15, at 20:06.

  7. #37
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    Quote Originally Posted by drhuy View Post
    is ariane made by private enterprise?
    Umm, yes? Arianespace is the biggest competitor of SpaceX for commercial spaceflight, you know.

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    Quote Originally Posted by kato View Post
    Umm, yes? Arianespace is the biggest competitor of SpaceX for commercial spaceflight, you know.
    you know, we're talking about Ariane (the rocket), not Arianespace (the company). "ARIANE", and "ARINESPACE", you know. The 2 words look quite different, you know.

    and how about the 2nd part "can its booster land vertically back to earth?"

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    Name:  ariane17.jpg
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    Looks pretty vertical to me.

  10. #40
    Senior Contributor DonBelt's Avatar
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    Ha- taxidermy man, he gonna have a heart attack when he see what I brung him. And all I ever snag when I'm fishing is dead logs or weeds. I am curious though what the amount of work is to reuse a booster that has "splashed down" in salt water vs one that lands relatively softly on dry land.

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    Quote Originally Posted by kato View Post
    Name:  ariane17.jpg
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    Looks pretty vertical to me.
    oh, so thats how you define "to land vertically". Genius!

  12. #42
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    So this was faster than I expected.

    Elon Musk Tweeted that the Falcon 9 is back in the hangar, no damage has been found, and it is ready to fire again. Apparently SpaceX is planning to do a full length static burn with the engines from the first stage that landed to closely evaluate their performance and ability to be reused.

    Here you can see some before and after pictures of the Falcon 9 first stage, showing the superficially erosive effects of hypersonic reentry.

    Name:  U9IlFaf.jpg
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    A few more interesting nuggets have come out of SpaceX job postings that give some insight into their goals as a company. You can see in their job postings that SpaceX wants to achieve 48 hour turnaround from stage arrival to launch and they want to create a fully automated launch system capable of rolling the vehicle to the pad, raising it to position, fueling, and executing a full launch sequence in a single hour.

    48 hour turnaround:http://www.spacex.com/careers/position/8642
    Fully automated launch system:http://www.spacex.com/careers/position/7829

    When I first saw these goals I was a bit confused because there aren't enough launch customers to really take advantage of such a short turnaround time. Upon further reflection however, there are definitely some usage scenarios that could take advantage of such a rapid launch pace. One would be rapid replacement of space based infrastructure destroyed in an ASAT campaign. ASAT is already a difficult undertaking, and it becomes a lot less appealing if it only knocks out your opponent's infrastructure for a matter of days or weeks as opposed to months or years.

    Another time when rapid turnaround on rockets could see a lot of use is during a future Mars mission, where there will be a relatively short burst of heavy launch activity to try to make the most of each Mars transfer window. It also opens the door to the use of multiple smaller rockets and orbital spacecraft assembly rather than necessitating the use of monsters like the SLS to loft a Mars mission in one shot.

  13. #43
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    Quote Originally Posted by SteveDaPirate View Post
    When I first saw these goals I was a bit confused because there aren't enough launch customers to really take advantage of such a short turnaround time.
    There are launch customers coming up for which a hundred+ launch per year rate is both a feasible and desired solution, mostly the massive space-based internet constellations being planned by e.g. OneWeb (720 satellites) or Samsung (up to 4600 satellites); SpX also has plans to get into that business itself as a satellite operator. As a launch provider, SpaceX already lost out on the OneWeb contract, which Arianespace and Virgin Galactic have won with over sixty launches being planned. Rapid turnaround would be key for SpX to corner that market.

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    Quote Originally Posted by SteveDaPirate View Post
    48 hour turnaround:http://www.spacex.com/careers/position/8642
    Fully automated launch system:http://www.spacex.com/careers/position/7829

    When I first saw these goals I was a bit confused because there aren't enough launch customers to really take advantage of such a short turnaround time. Upon further reflection however, there are definitely some usage scenarios that could take advantage of such a rapid launch pace. One would be rapid replacement of space based infrastructure destroyed in an ASAT campaign. ASAT is already a difficult undertaking, and it becomes a lot less appealing if it only knocks out your opponent's infrastructure for a matter of days or weeks as opposed to months or years.
    Exactly. If another war happens between the major powers it will have a component in space. If Russia and China were not convinced to go after US space assets before, they're probably well convinced now after two years of the US boasting about seeing everything from airline shoot downs to Sukhois and cruise missiles using satellites.

    If there's a fight with the US what happens to those airplanes, missiles, and launch platforms that US satellites can see in real time?

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    Given that China, Russia and the EU all each lift the same amount of observation sats every year as the US nowadays, they don't really need the US boasting...

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