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Random Rockets

Rockets failing often but cheap to build
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The major cost of space launch is the vehicle, not the fuel. That's why Elon Musk is trying to build rockets that get back to earth in one piece.

In general - the trend has always been to build robust rockets that can deliver the payload almost every time.

But what if we went another way? What if we cut corners here and there, and we were able to build a rocket that succeeds only 10% of the time (and even then it doesn't always get to the right orbit), but is 100 times cheaper to produce?

Obviously, it would be no good to deliver humans or expensive equipment to the orbit, but cheap things, like water or other 3d-printing material?

kolinko, Feb 22 2015

n prise http://en.wikipedia.org/wiki/N-Prize
what is an N-Prize (qv) ? [popbottle, Feb 22 2015]

3D Printer in Orbit http://www.collects...tation-ratchet.html
[MechE, Feb 26 2015]

Kessler Cascade http://en.wikipedia...ki/Kessler_syndrome
Why large bits of space junk are bad. [MechE, Feb 27 2015]

[link]






       The N-Prize (qv) was made for you, [kolinko].
MaxwellBuchanan, Feb 22 2015
  

       The // 100 times cheaper // target is going to be tough to hit, because of the economies of scale of building larger launch vehicles.   

       But it might be possible, using very simple solid-fuel motors.
8th of 7, Feb 22 2015
  

       @8th it wouldn't be cheaper because the rocket would be smaller, but because corners would be cut when building one. If anything, the economies of the scale would work for (not against) the idea, because hundreds of cheap rockets would be built.   

       @MaxwellBuchanan - good idea :)
kolinko, Feb 23 2015
  

       [kolinko], welcome to the Halfbakery.
normzone, Feb 23 2015
  

       Ooops - how rude of me! I hadn't noticed that [kolinko] was new here. Welcome, [kolinko] - wear these square brackets with pride. But don't tell your employer.
MaxwellBuchanan, Feb 23 2015
  

       Hahah, what do the square brackets mean? :) Or is it just a way to mention the users? :)
kolinko, Feb 25 2015
  

       ^ More like quarantine. Isn't that right [[[MaxwellBuchanan]]]?! Welcome to the HalfBakery [kolinko]
AusCan531, Feb 25 2015
  

       By convention, [kolinko], usernames are enclosed in square brackets.   

       Quoted text is shown using the C and C++ convention of a double slash , as in // how rude of me! //   

       Using the @ symbol is considered somewhat gauche   

       It is traditional for newcomers to be welcomed in a friendly manner, allowed to post a few ideas, and then be mercilessly savaged by the existing members for some trivial error of grammar, mathematics, logic, or trangressing one of the numerous "unwritten rules" but mostly just for cheap amusememt.   

       Those without a rhinoceros -like hide need not apply ; "Can't take a joke, shouldn't have joined."
8th of 7, Feb 25 2015
  

       Because if we used curly brackets like this - {kolinko} - we'd be in the area of Set Theory and saying that there was a set of users which contained only "kolinko" - clearly nonsense, whereas square brackets usually denote a matrix or, in programming, an array, which makes a lot more sense.
hippo, Feb 25 2015
  

       Also, the HalfBakery has links to a manufacturer of square brackets, so we get them at cost.
MaxwellBuchanan, Feb 25 2015
  

       I think the problem is that the cost to build the rocket is only a small portion of the total launch cost. Even if your cargo is low value, fueling the rocket is not cheap.   

       Also some things, even in a disposable rocket, can't be scrimped on. You're still going to need range safety officers and functionality, in fact you're probably going to need more of it. Likewise, your docking and transfer functionality needs to be 100% reliable, or at least completely fail safe, so it doesn't damage whatever you are delivering to.   

       Not to mention if a bunch of these reach the wrong orbit, you're adding to the space-junk issue, and increasing the risk of a Kessler cascade.
MechE, Feb 25 2015
  

       // 100% reliable, or at least completely fail safe, //   

       You're no fun any more ...   

       // the HalfBakery has links to a manufacturer of square brackets //   

       Beware ! "the HalfBakery has links to a manufacturer of square brackets" would be more honest if it read "M'lord Buchanan's family have extensive financial interests in a vast, greedy, bloated, exploitative commercial empire of very dubious legality and non-existent ethics, who have obtained control - no doubt by underhand means - of resources in an impoverished third world country, where small children can be forced to work very long hours in appalling conditions almost indistinguishable from slavery, manufacturing minimum-spec product - including square brackets - at a fraction of the normal manufacturing cost of the item, then getting them imported duty-free into Western markets by greasing the palms of customs officials, and then sold at slightly below the going rate in counterfeit packaging, thus garnering enormous profits, which are then laundered through a complex chain of holding companies before being converted into either cash, precious metals or uncut jewels and surreptitiously added to the Smaug-like hoard of treasure in the basement of Buchanan Towers."
8th of 7, Feb 25 2015
  

       That's what I said.
MaxwellBuchanan, Feb 25 2015
  

       Well, yes, admittedly your version is concise, pithy and to the point, but [kolinko] is new here.
8th of 7, Feb 25 2015
  

       // for some trivial error of grammar //   

       No error of grammar is ever trivial.   

       I will be watching you, [kolinko]. Welcome.   

       On a less important note . . .   

       I agree with [MechE] about the cost of fuel being a large percentage of the cost, as well as the costs of staging a launch - especially if it might fail. I'd vote for as many safety features as possible - which is usually the point at which a failure of the safety system becomes more likely than the failure of the base system, and on a rocket is when the weight of the safeties exceeds the lifting power of the rocket.   

       But there could be something to be said for a dead-basic rocket, like solid-fuel, ceramic-nozzle, and wrapped-body, that failed only 10% of the time. I realize that is just an Estes model rocket motor, and the sounding-rocket people are probably already doing something much like that . . .
baconbrain, Feb 25 2015
  

       Well, as the last part of the original idea says, it is for water or raw materials, not expensive things.   

       Resin for a 3D printer is interesting, but in that case I'd argue for building ten copies of the desired part down on Earth, and slapping them into ten of the maybe-make-it rockets. You can send the file for printing a part via radio, and get a crappy rocket under way pretty quickly. (Not that a printer in space would be bad - if it was needed, it would be needed bad. And a crappy rocket might not be best for docking with the station.)   

       Hmm. How about this idea as posted, for the first two stages of a rocket, with the final stage made really well? If the first two stages went boom, the final stage would have the guts to get up and away, then make a good landing with the expensive cargo (which would probably be shards after that, so never mind).   

       The other cargo for a maybe rocket could be fuel. (After all I said about fuel cost.) Tanks of liquid fuel in orbit would be of great value. And if the rocket starts to blow, the fuel would be self-disposing, if you got the self-destruct signal in time. Heck fire, you could launch fuel carriers and charge people to watch them blow up - the occasional dud that made it to orbit would pay for the refunds.
baconbrain, Feb 25 2015
  

       Except that the 3d printer is already in orbit (see link). The advantages are A) that it's a lot more flexible to have some resin around if you aren't sure which tool or part you'll need, and B) in theory the resin could be reprocessed multiple times, although I don't know if that capability is actually in place.
MechE, Feb 26 2015
  

       //I think the problem is that the cost to build the rocket is only a small portion of the total launch cost. //   

       It's not really. E.g. the fuel cost for Falcon 9 is just $200k, while the total launch cost is around $50M. (according to Wikipedia)   

       «MaxwellBuchanan» «hippo» - what about those? :)
kolinko, Feb 27 2015
  

       Very nice, except that (1) they make my eyes go funny, and (2) I don't know how to type them.
hippo, Feb 27 2015
  

       Fuel was only one example. However, if you're trying to get your launch cost down to 10% of the current, then that 200k of fuel just ate up about 4% of your total available funds.   

       That being said, my point is that a lot of things don't scale.   

       Let's say most systems on rocket are triply redundant. If you cut out all redundancy, say you cut the material costs to 1/3 (you don't, but as an approximation). That cuts your reliability far more, because you go from only having a problem when three identical systems fail to having a problem when any single system fails. Being generous, lets say this gets you to your 10% reliability.   

       You still need at least 70-80% of the personnel for each launch, even cutting corners, although I'll allow some economies of scale, call it 50%.   

       Now add back in 10% for the extra range safety personnel. Then add back in 10% of material costs for the systems that are critical for the safety of the delivery point (your approach and docking systems, mostly).   

       I don't have real numbers for any of this, but it should be fairly clear that reliability falls much more quickly than cost.   

       And I repeat my point about space junk and a Kessler cascade.
MechE, Feb 27 2015
  

       // in theory the resin could be reprocessed multiple times, although I don't know if that capability is actually in place. //   

       Hmmm, 3D-printed resin rocket ?
8th of 7, Feb 27 2015
  

       [MechE] those are some good points, thanks.
kolinko, Feb 28 2015
  
      
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