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Thread: Someone said solids weren't the way to go!!

  1. #1
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    Someone said solids weren't the way to go!!

    A couple of years ago i was in a debate over solids vs liquids on here.

    Experts on here told me in no uncertain terms that solids were not practical and Nasa was wasting it's time.

    Well it looks like someone forgot to tell the Europeans.

    http://www.space.com/14538-european-...en-launch.html

    They have a new Vega rocket.

    The rocket is made up of four stages — three solid-propellant stages and a fourth stage, called AVUM, that carries the payload.

  2. #2
    That discussion was about manned spaceflight, Sam, as well you know.

  3. #3
    On a slightly more relevant note, Vega just made its first launch. I don't see any thread here on BAUT?

    Anyway, the flight was succesful. Vega launched 9 (!) satellites into orbit. Video can be found here:

    http://multimedia.esa.int/Videos/201...ication-flight

    Wow, takeoff is rather instantaneous for a single solid stage. And the acceleration of that thing is FAST! Look at it climbing in the sky!

    Vega + Ariane 5 is quite an unmanned capability for ESA. Way to go!

  4. #4
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    Quote Originally Posted by Nicolas View Post
    On a slightly more relevant note, Vega just made its first launch. I don't see any thread here on BAUT?
    I noticed the same thing. Perhaps we can turn this thread into a Vega thread rather than just re-hashing the old liquid/solid debate.
    Samkent.. what do you think?

    Anyway, I couldn't get to the video in your link... Probably country differences. So; I looked for a US friendly link and found it on Space.com.

  5. #5
    I looked for a US friendly link and found it on Space.com.
    You mean they skip the part where they burn US flags in the control room in that version? My link indeed seems dead at the moment.

    I'm all for turning this thread into "the" Vega thread. While it certainly is interesting to have an all solids (minus upper stage) launcher, this shouldn't be put in a boxing ring context.

    I knew people who worked on Vega back in the days when I worked at ESA. They must be so proud.

    Sidenote: at least one of our major online newspapers hasn't mentioned the launch yet. Most likely because it did not blow up.

  6. #6
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    Must be some nasty G forces on the electronics there...

  7. #7
    Not too bad...it's not like a Nike Sprint missile.
    Last edited by Nicolas; 2012-Feb-13 at 04:44 PM. Reason: added Sprint

  8. #8
    I like how Ariane5 appears to have 2 solids but is all liquid, while for Vega it's the other way around. Still very little news coverage on the launch in this country...

  9. #9
    Umm - Ariane 5 isn't all liquid. Those two solids on an Ariane 5.......are actually solids.

    http://www.arianespace.com/launch-se...ne-5-intro.asp

  10. #10
    That's what I get for getting up early. Totally confused the Ariane 5 SRB's with the Energia stack who appears to have SRB's, but it are liquid boosters. And I won't try to weasel out of it by telling you that Russia is sometimes considered part of Europe as well.

    OK, so Vega actually has a solid rocket heritage within ESA indeed. Makes sense.

  11. #11
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    Vega for small sats--Ariane 5 parent for largest ones--with medium payloads handled by the new R-7 pad--taking the place for the defunct Ariane 4.

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    Quote Originally Posted by JustAFriend View Post
    Must be some nasty G forces on the electronics there...
    The user manual is available here: http://www.arianespace.com/launch-se...9;s-manual.asp

    and it says (page 35 in the PDF) that maximum acceleration is 5.5g vertical and 0.9g lateral.

    Achievable payload is given on p. 28 in the PDF. The performance target is specified as 1'500 kg to 700km polar orbit. Looks like a launcher for Earth observation sats. Performance to Earth escape is not given .

    January 2012 article on pricing: http://www.spacenews.com/launch/0123...n-rockets.html

    Europe’s Vega small-satellite launcher, whose inaugural flight is scheduled for mid-February, will be sold commercially for about 32 million euros ($42 million) per launch — a price that can compete with converted Russian ballistic missiles, Vega officials said Jan. 23.
    That works out to 28'000 $/kg.

    “What we are saying is that we can now deliver the vehicle for 25 million euros to Arianespace,” De Pasquale said in an interview on the eve of Vega’s final tests before flight approval.

    “Arianespace’s marketing and service costs will add about 7 million to that figure, which gets us to 32 million euros. This is assuming that we launch only two Vega flights per year. If we can increase the flight rate to four per year — and we believe the market demand will be there — then our price per vehicle can drop to 22 million euros. We assume a corresponding price drop from Arianespace,” De Pasquale said.
    That would correspond to 19'250 $/kg.

  13. #13
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    5.5G is less than Gemini-Titan, so nay too bad if you wanted to stick a meat bag on the top.

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    Quote Originally Posted by Glom View Post
    5.5G is less than Gemini-Titan, so nay too bad if you wanted to stick a meat bag on the top.
    Vega's max payload is 2300kg -- to 5 deg. 300km orbit. Gemini capsule weighting 3'605 kg wouldn't fit. OTOH, Mercury, at 1'360kg, would.

    ...Someone would have to be truly desperate to try that though

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    Quote Originally Posted by kamaz View Post
    Vega's max payload is 2300kg -- to 5 deg. 300km orbit. Gemini capsule weighting 3'605 kg wouldn't fit. OTOH, Mercury, at 1'360kg, would.

    ...Someone would have to be truly desperate to try that though
    I did say a meat bag, not a pair. Although you could include the booze, if Schirra was said animal product.

  16. #16
    Quote Originally Posted by JustAFriend View Post
    Must be some nasty G forces on the electronics there...
    As others have said, don't judge a vehicle's max acceleration by how fast it jumps off the pad. A vehicle will typically experience the highest G forces near the end of a given stage burn and that's much higher than you'll ever see of any orbital launch vehicle liftoff acceleration. 5.5 G should be pretty typical for that payload class, bigger class vehicles are around 5 G limits. Liftoff accels are probably around 1.5 G or less.

  17. #17
    Quote Originally Posted by JustAFriend View Post
    Must be some nasty G forces on the electronics there...
    Nowhere near as bad as New Horizons on the third stage of it's launch vehicle ( peaked at over 10 G )

  18. #18
    ...Or a Nike Sprint, as said. 100g-130g acceleration, reaching Mach 10 in 5 seconds. After one second, it already went more than 3000km/h and had already traveled half a kilometer (assuming the 100g is constant for the first stage). Captain Obvious adds that it was unmanned.

    Its first stage burned only 1.2 seconds. How's that for "live fast, die young". In fact you could say that was already its second stage, as it was already thrown up by a piston before that.

  19. #19
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    Couple of points:

    1. $/kg isn't always a useful comparison. $/Launch is also relevant and its a fairly cheap (not Falcon 1 cheap, but still cheap - and Falcon 1/1e seems to have been pushed aside a bit now by SpaceX)

    2. The motivation behind this might, if the cynic in me is correct, not be entirely to optimize spaceflight. Solid rockets have more utility in military applications than in spaceflight, so I tend to think that solid booster development is always (at least in part) a way to keep useful military R&D off the defence budget of the country in question.

    3. Not being entirely cynical, part of the motivation is also to develop better solids to feed back into the Ariane program. The first stage of Vega is similar to the boosters used on Ariane 5, but has a lighter casing and better thrust vectoring. The notion is, I believe, that these improvements will form the basis of a later Ariane 5 payload upgrade (or a next generation Ariane launcher)

  20. #20
    I don't know about 2 in case of ESA/Europe. Unless they're keeping their missile wishlist very secret.
    3 would be an example of good crossover of knowledge and hardware.

  21. #21
    The actual motor of the Vega's first stage has about half the thrust and burns half as long as the Ariane V solids - but there will be some carry over, I'm sure.

  22. #22
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    Quote Originally Posted by Nicolas View Post
    ...Or a Nike Sprint, as said. 100g-130g acceleration, reaching Mach 10 in 5 seconds.
    My HIBEX beats your Sprint:

    The HIBEX missile achieved nearly 400 g peak axiai and over 60 g lateral acceleration, reaching a velocity of nearly Ma = 8, in a little over 1-sec burn time, with pitch over from a vertical ejection from a silo to a trajectory of 15 deg elevation. In 2 more years, UPSTAGE, a maneuvering HIBEX second stage, demonstrated over 300 g lateral acceleration and a side-force specific impulse Isp > 1000 sec using external burning, jet flow control techniques and a laser gyro for guidance.
    http://highpowerrocketry.blogspot.co...abm-tests.html

    I am particularly intrigued by the claim that a chemical rocket had Isp over 1000s.... Some more information about this, let's just say unique, system: http://www.alternatewars.com/WW3/WW3...A_II_HIBEX.htm

  23. #23
    We were firing shells containing vacuum tube based radar fuzes ~60 years ago, and now have working electronically guided bullets. We're talking thousands of g. For electronics, a few tens of gravities is nothing real difficult to deal with.

    As for the HIBEX specific impulse, that was specifically for the transverse maneuvering. It sounds like it was burning propellant externally in air...something like a ramjet effect on the side of the missile (just the second stage, I think). The high specific impulse was because it wasn't using chemical rockets for forward acceleration, it was using an airbreathing technique for sideways acceleration.

  24. #24
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    Quote Originally Posted by kamaz View Post
    That works out to 28'000 $/kg.
    Less than $9k/lb? That's pretty low, isn't it?

  25. #25
    Quote Originally Posted by DoggerDan View Post
    Less than $9k/lb? That's pretty low, isn't it?
    How does that math work out?

  26. #26
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    Quote Originally Posted by DoggerDan View Post
    Less than $9k/lb? That's pretty low, isn't it?
    1kg= 2.2 lbs, so it's more like $12, 727.00/lb.

  27. #27
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    Quote Originally Posted by Damburger View Post
    Couple of points:

    2. The motivation behind this might, if the cynic in me is correct, not be entirely to optimize spaceflight. Solid rockets have more utility in military applications than in spaceflight, so I tend to think that solid booster development is always (at least in part) a way to keep useful military R&D off the defence budget of the country in question.
    Absolutely. Solids are much more complex in terms of material science than you would suspect; and this is essentially a fixed cost.

    The other, not often mentioned driver is the launch pad footprint: Solids provide a LOT of thrust per cc of nozzle cross section from a fairly dense core. Solids will make sense as long as staged boosters make sense.

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