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SpaceX's Grasshopper VTVL takes a 40 meter hop

  • 27-12-2012 10:05pm
    #1
    Closed Accounts Posts: 1,190 ✭✭✭Squeaky the Squirrel


    http://www.gizmag.com/spacex-grasshopper-vtvl-test/25562/
    The SpaceX Grasshopper vertical takeoff vertical landing (VTVL) testbed has successfully flown to a height of 40 meters (131 ft), hovered for a bit and subsequently landed in a picture perfect test on December 17, 2012.

    Despite their seeming inefficiency, vertical takeoff vertical landing (VTVL) rockets have long been a fixture in the world of space flight. The first manned VTVL spacecraft was the Apollo Lunar Lander, which landed on and took off from the Moon vertically, a task made far easier by the Moon's one-sixth gravity.




    Grasshopper is also distinguished from most other VTVL craft in that it is the testbed of a project to convert an active commercial orbital medium-lift (10,000 kg to low earth orbit) launch vehicle into a recoverable launch system. Prior VTVL craft (aside from the Lunar Lander) were intended to be research vehicles or one-off demonstrators.
    Nearly 2013...you'd think we'd be further along than messing around trying to make a reusable rocket...wheres the spaceships?


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Comments

  • Closed Accounts Posts: 225 ✭✭vonbarracuda


    Impressive


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69


    amazing it looks like the delta clipper

    can't wait to see this thing go higher and faster

    Mars and the moon get closer every day


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69


    Nearly 2013...you'd think we'd be further along than messing around trying to make a reusable rocket...wheres the spaceships?

    give it a few years and spaceX will land their dragon spacecraft using rockets, when they do that my bet is the average man in the street will understand what they are trying to do

    most people think the US are falling behind other countries in space technology, but they are about to move far ahead


  • Registered Users Posts: 8,551 ✭✭✭Rubecula


    Impressive

    Yes indeed it looks very impressive, I wonder on how much fuel it had on board and how much of it it used up?


  • Closed Accounts Posts: 1,190 ✭✭✭Squeaky the Squirrel




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  • Registered Users Posts: 4,534 ✭✭✭AugustusMinimus


    I hear that it's actually more efficient to use a rocket power to land a rocket than using a parachute and having a sea landing.

    When you think about it, if you are going to land a dragon capsule, after aero braking, it will only be doing about 120-160mph in the lower atmosphere due to drag. At this point, it prob wouldn't take that much fuel to land it.


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69


    I hear that it's actually more efficient to use a rocket power to land a rocket than using a parachute and having a sea landing.

    When you think about it, if you are going to land a dragon capsule, after aero braking, it will only be doing about 120-160mph in the lower atmosphere due to drag. At this point, it prob wouldn't take that much fuel to land it.

    they need to add a launch abort system and the plan to use the same rockets to land the capsule, far better than parachutes

    the other good thing is they will be able to land the dragon almost anwhere they want, no runways needed


  • Closed Accounts Posts: 1,190 ✭✭✭Squeaky the Squirrel




  • Closed Accounts Posts: 2,050 ✭✭✭nokia69




    the DC-X was an attempt to do something like the spaceX grasshopper but it never got enough funding

    some of engineers who worked on the DC-X now work for blue origin, so I don't see them running out of cash any time soon, I wish they put out more videos its hard to know how much progress they are making

    I think it will be easier for spaceX because they can attack the problem from both ends


  • Registered Users Posts: 9,573 ✭✭✭lord lucan


    Nearly 2013...you'd think we'd be further along than messing around trying to make a reusable rocket...wheres the spaceships?

    2013 and NASA are using Apollo era technology to help them develop the next generation of launcher.

    They've re-assembled an F-1 engine,the very same that powered the Saturn V's,from parts that have been left on display in museums and an unused F-1 at Marshall Space Flight Center. It was even hot fired just over a week ago.

    http://www.collectspace.com/news/news-012113a.html


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  • Closed Accounts Posts: 1,190 ✭✭✭Squeaky the Squirrel




    single angle



  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,537 Mod ✭✭✭✭Capt'n Midnight


    Despite their seeming inefficiency, vertical takeoff vertical landing (VTVL) rockets have long been a fixture in the world of space flight. The first manned VTVL spacecraft was the Apollo Lunar Lander, which landed on and took off from the Moon vertically, a task made far easier by the Moon's one-sixth gravity.
    [/qoute]Actually the Russians used retro rockets on the first manned space flight.
    There is a lot of re-inventing the wheel in US space flight

    Anyone remember this from the 90's ?

    en.wikipedia.org/wiki/McDonnell_Douglas_DC-X

    Despite all the hype it was just a normal rocket with better electronics.


    Nearly 2013...you'd think we'd be further along than messing around trying to make a reusable rocket...wheres the spaceships?
    Why do we need a reusable rocket ?

    The other way of making something cheap is to have long production runs so you get economies of scale and constant improvements.

    With short production runs everything is more or less at what would have earlier been called the pre-production prototype stage , you don't get a chance to improve the design much.


    In the West there is far too much engineering to add lightness on the bottom stages. Rocket fuel is cheap - it takes a lot of flights to save the fuel used in testing.

    Reliability is key. And a simple way of adding reliability is to overengineer because the addition strength may prove useful for failure modes that aren't understood.


    Yes a reusable rocket would be nice, but not if it costs more , or isn't reliable


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,537 Mod ✭✭✭✭Capt'n Midnight


    lord lucan wrote: »
    2013 and NASA are using Apollo era technology to help them develop the next generation of launcher.
    At some time in the future NASA won't have to keep relying on 1950s Soviet era technology for all their manned launches.

    Rockets haven't changed much, all the gains since the 1950's are in the order of a few %

    Rocket fuel hasn't gotten better because there are only a finite number of low molecular weight compounds. Though ALICE is interesting for first stage boosters.

    The big improvements include
    - staged combustion so you don't loose the turbopump output
    - better control of fuel / oxidiser ratio , there's a nice article about control system maths allowing over 4000lbs more payload on the Saturn V
    - lighter materials , the reduction of the weight of the shuttle external tank being the big one here. Over the life of the shuttle they saved 9 tons. Of course the savings would have been much lower if it had been a second stage tank, and it's still less than 0.3% of the launch mass.
    - better electronics, lighter , cheaper , it all helps especially when it can do stuff on the fly that would have taken weeks and hundreds of thousand dollars back in the 60's
    - shuttle engines (for example) can run at over 100% of the designed rating, this saves a little on gravity drag



    It's all about tweaking that last little bit of performance out of the system
    SCHEMES FOR ENHANCING THE SATURN V MOON ROCKET’S TRANSLUNAR PAYLOAD CAPABILITY http://www.aticourses.com/enhancing_saturn_v_moon_rocket.htm



    I don't understand why there aren't more high altitude launch sites as this would reduce atmospheric friction / pressure , and also mean you could use lighter shrouding and it would make the engines more efficient than at sea level. It also saves you a small amount of climbing.


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69


    [/qoute]Actually the Russians used retro rockets on the first manned space flight.
    There is a lot of re-inventing the wheel in US space flight

    Anyone remember this from the 90's ?

    en.wikipedia.org/wiki/McDonnell_Douglas_DC-X

    Despite all the hype it was just a normal rocket with better electronics.



    Why do we need a reusable rocket ?

    The other way of making something cheap is to have long production runs so you get economies of scale and constant improvements.

    With short production runs everything is more or less at what would have earlier been called the pre-production prototype stage , you don't get a chance to improve the design much.


    In the West there is far too much engineering to add lightness on the bottom stages. Rocket fuel is cheap - it takes a lot of flights to save the fuel used in testing.

    Reliability is key. And a simple way of adding reliability is to overengineer because the addition strength may prove useful for failure modes that aren't understood.


    Yes a reusable rocket would be nice, but not if it costs more , or isn't reliable

    it depends what you mean by costs more

    if you mean cost more to launch then I agree, the shuttle was reuseable but in the end it was a waste of money because the launch cost was far too high

    but if the reuseable rocket costs 10 times as much to build but gets used 1000 times then that would see launch costs fall far below what we have today, it needs to work like air travel, the rocket lands gets more fuel then launches again

    even if spaceX can only make the first stage reuseable it will result in lower launch costs

    the next falcon 9 launch should be interesting, its the new version of the falcon 9 and they are going to try to restart the first stage and land it at sea


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,537 Mod ✭✭✭✭Capt'n Midnight


    nokia69 wrote: »
    it depends what you mean by costs more
    ...
    but if the reuseable rocket costs 10 times as much to build but gets used 1000 times then that would see launch costs fall far below what we have today, it needs to work like air travel, the rocket lands gets more fuel then launches again
    You have to remember that especially for the first stage rocket fuel is cheap and fuel tanks are cheap.

    Your payload is only a few % of the launch mass. Carrying a fuel tank to orbit seriously affects payload. The shuttle external tank was 26.5 tons compared to a payload of 24 tons, (for polar orbit it was just 12.7 tons). Because the tank was external it was actually a lot lighter than the original 35 tons. If you were to try and land the tank then you'd need extra structure and shielding so I'd nearly guess that your payload to polar orbit would be negligible.



    NASA lost a shuttle because the solid boosters were reusable. Other wise they wouldn't have needed O rings because there would have been no joints. I'm fairly sure that they didn't save the cost of an orbiter by refurbishing the boosters. unintended consequences and pork barrelling


    You should only reuse the bits it's worth reusing.

    Reusing the second stage eats into your payload
    Reusing the first stage doesn't save you a lot of money

    Having a spaceplane instead of a capsule gives you more options but development costs would be fairly high. Reusing a capsule kinda makes sense if only because you have to return the crew.

    That said I'd like to see skylon working

    http://www.forbes.com/sites/carolpinchefsky/2012/04/18/5-horrifying-facts-you-didnt-know-about-the-space-shuttle/2/
    On the other hand, the Soyuz, the vehicle of choice of the Russian Space Agency (RSA), is less expensive by an order of magnitude. So how much does it cost to launch?

    Watson said, “That number has never been publicized by the RSA, but it’s rumored to be as low as $45 million. Of course, in accordance with supply & demand, they’re now selling seats for $63 million a piece: initially “tickets” were selling for around $20 million.


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69




    the grasshopper made another flight a few days ago


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69




    another flight for the grasshopper, this time 325m, I think they will be doing the next tests in new mexico because they will be going higher and faster


  • Site Banned Posts: 25 Leader of the Furlings




  • Closed Accounts Posts: 2,050 ✭✭✭nokia69


    It goes sideways to.:eek:

    it needs to if they want to land in the right place

    the next falcon 9 launch should be interesting, they want to try and land the first stage at sea, sept 5 I think

    and since its more or less a new rocket the chance of launch failure is higher than normal


  • Site Banned Posts: 25 Leader of the Furlings


    nokia69 wrote: »
    it needs to if they want to land in the right place
    only kidding


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  • Closed Accounts Posts: 2,050 ✭✭✭nokia69




    the grasshopper went higher

    and the attempt to restart the first stage of the new falcon 9 worked

    Mars is getting closer every day :D


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69




    :D


  • Registered Users Posts: 8,551 ✭✭✭Rubecula


    Any idea what the next step is?


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69


    try to recover a first stage from the sea, this might be hard depending on the weather, but it went well on the last flight

    then land a first stage on land and fly it again


  • Registered Users Posts: 4,534 ✭✭✭AugustusMinimus


    What sort of savings are SpaceX expecting to be made ?

    Have they stated how many teams they expect each first stage to be reused ?


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69


    What sort of savings are SpaceX expecting to be made ?

    Have they stated how many teams they expect each first stage to be reused ?

    well the first stage makes up 70% of the rocket cost

    they said a while back that they hoped to get the falcon 9 price down to 7 or eight million

    they never said how many times the same first stage could be reused, my guess is they want to be able to reuse it hundreds of times, thats the goal


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,537 Mod ✭✭✭✭Capt'n Midnight


    nokia69 wrote: »
    well the first stage makes up 70% of the rocket cost

    they said a while back that they hoped to get the falcon 9 price down to 7 or eight million

    they never said how many times the same first stage could be reused, my guess is they want to be able to reuse it hundreds of times, thats the goal
    70% is crazy unless it's human rated.

    First stage is where things like specific impulse aren't that important. And there is no multiplier effect like on upper stages. You just want a big dumb booster, rocket fuel is cheap.


    Space Shuttle "reusable" solid boosters consisted sections joined by O rings. A few sections were reused 7 times. So it's doubtful if they saved any money , factor in the loss of a shuttle and the attempt at reuse was a total waste of resources and lives.


    The way to reduce costs is volume. With wind turbines every time global capacity doubles costs drop by 14%. The Soyuz family has over 1,700 launches at this stage.


    The US shot themselves in the foot with the SST. Boeing went through more money designing a Mach 3 airliner than it cost to get Concorde built.

    Several problems with the SST, one was noise, but another was an inability to do basic maths. A Mach 3 airliner would cost more. But it could do three times as many journeys per day than existing airliners. So the airlines would only need to order 1/3rd as many. Lower volume means R&D costs spread over fewer aircraft which raises the price and the whole thing spirals.

    Don't forget that most of the cost of getting the Shuttle ready was for refurbishing rather than the fuel.


  • Closed Accounts Posts: 2,050 ✭✭✭nokia69


    well spaceX have said the the first stage costs 70% I don't see how being man rated or not would change that

    the goal for the falcon 9R is to have zero refurbishing thats the whole point


  • Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,537 Mod ✭✭✭✭Capt'n Midnight


    Here's the thing. Russia launch about half of all commercial satellites.

    Half the US launches last year relied on Russian Engines or First Stage sections.
    ULA / Atlas / RD180 / Zenith based stuff.

    Space X don't rely on this stuff.


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  • Closed Accounts Posts: 2,050 ✭✭✭nokia69


    Here's the thing. Russia launch about half of all commercial satellites.

    Half the US launches last year relied on Russian Engines or First Stage sections.
    ULA / Atlas / RD180 / Zenith based stuff.

    Space X don't rely on this stuff.

    I know

    ULA are in serious trouble IMO the days of milking the US government are coming to an end


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