Could you construct an orbital stick stabilized rocket, by scaling up a firework?
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$\begingroup$ updated to chemical not water $\endgroup$– MuzeNov 19, 2018 at 21:49
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1$\begingroup$ Still a dup of space.stackexchange.com/questions/30972/… If you're not even going to remember your own questions... $\endgroup$– AntziNov 20, 2018 at 7:45
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2$\begingroup$ I dont see why this is marked as a duplicate, really. Neither the water-rocket to space question or its highest-voted answer mention scaling up the solution. They deal with using multiple small bottles. This question explicitly asks if scaling upwards is a valid strategy, which is as aspect NOT covered by the other questions. $\endgroup$– InnovineNov 21, 2018 at 13:13
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1$\begingroup$ Muze, very often people need to come in and ask comment questions to get clear what you actually mean. Then there are a lot of edits, and the question sometimes completely changes correction. Not to mention the on hold / reopen cycles it then goes through. Is there something you can do to prepare your questions better? Hint: Ask that on the meta site. $\endgroup$– user10509Dec 19, 2018 at 14:04
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3 Answers
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Based on Single-stage-to-orbit, I don't think so. This article quotes Robert Truax who said that the structural weight needs to be aggressively minimized for SSTO, which is what your question asks about. Bottle rockets use paper as the main component of their structure, and that's not going to be strong and light.
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With the change "Materials would not be the same of course..." The issue is still that SSTO is hard, and multiple stages offer advantages over a single. For example, from that same Wikipedia article, the stages can be engineered to maximize efficiency for their particular role in the trajectory of the flight. You'd get much more bang for the buck by making a two-stage bottle rocket than a large single-stage rocket.
answered Nov 19, 2018 at 20:07
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$\begingroup$ I think OP is looking for ways to send very long poles into orbit, SSTO or 2STO, rather than literally trying to scale up a bottle rocket. $\endgroup$ Nov 19, 2018 at 20:54
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$\begingroup$ OP says, "Could a bottle rocket be up scaled to achieve orbit?" Yes, that's the larger goal. This question asks whether scaling bottle rockets is a way to do that. $\endgroup$ Nov 19, 2018 at 20:57
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The classic bottle rocket design is optimised for stability during launch at low cost. The stick part both acts as a launch rail and keeps the center of drag well aft to prevent tumbling. The cost of this is weight since you effectively fly with part of your launch system still attached and the drag could be achieved with fins or avoided entirely with thrust vectoring.
So for any rocket with active control there is no advantage, and for uncontrolled flight fins and a launch rail will get more out of the same engine.
If the objective is to fly a long structural element as the payload itself then it becomes a bit different, since there are structural problems with flying a long thin structure on top of a long thin rocket so putting it alongside might be made to work. It will produce more frontal area and thus drag but may allow a lower rocket structural weight since loads from the high thrust stages can be directly applied to the spar rather than through the upper stages.
You probably would not want the spar extending past the first stage engines, both because of the heat effects and because it will block the thrust vector you need to keep thrust through center of mass, even if you have a twin structure your engine out modes may require vectoring through the spar/s unless you are launching enough of these things that simpler design can be traded against a percentage crashing (if this question is part of OP's series on space elevators).
Stage separation also becomes much more complex since you need to avoid striking the payload spar.
answered Nov 20, 2018 at 0:05
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$\begingroup$ Not actually answering with a yes or no though $\endgroup$– InnovineNov 20, 2018 at 7:26
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1$\begingroup$ @Innovine I'd say they said "no", a simple non-staged bottle rocket would have to be gigantic to make it to orbit, possibly a fraction the size of the earth itself due to the rocket equation. It's basically a giant solid-fuel single-stage booster. Can it escape the atmosphere without being massive? Yeah. Achieve orbit? Probably not. $\endgroup$ Nov 20, 2018 at 14:21
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$\begingroup$ Yes it would be gigantic. That is the question: does it scale up? Absolutely. If it doesn't leave the atmosphere, make it bigger. Make it big enough so it sticks out through the atmosphere. Make it so 99% of it is already above the atmosphere if you like. you can't answer a question on "does it scale" with "no, cos it would be gigantic". $\endgroup$– InnovineNov 21, 2018 at 8:07
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1$\begingroup$ @Innovine - probably not helping is that I grew up in a time and place where bottle rocket is en.wikipedia.org/wiki/Skyrocket, not a bottle full of water under pressure. $\endgroup$ Nov 21, 2018 at 8:57
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$\begingroup$ @GremlinWranger I don't think the choice of propellant plays much of a role, really. The concept of scaling up until orbital velocity is reachable applies to both solid fuel rocketry as it does to pressurized water rocketry. The efficiency is certainly different though, which probably explains why the shuttle boosters didn't use water :) $\endgroup$– InnovineNov 21, 2018 at 13:10
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Yes. The physics involved in thrust are independent of scale. A bottle rocket that is three hundred kilometers high and 100km in diameter will blast off and into orbit with little difficulty.
The problem is if we can make one big enough. The answer to that is no. Can we successfully launch one without destroying the surface of the Earth? Probably not.
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$\begingroup$ I think it will be really good if you put your calculations to back up your answer. $\endgroup$– AmarNov 20, 2018 at 7:40
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$\begingroup$ The physics of thrust are (generally) independent of scale, but delta-v doesn't scale up. $\endgroup$ Nov 20, 2018 at 22:57
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$\begingroup$ No math is needed. Lets look at the extreme end of the scale. We have a bottle rocket 10 times the mass of earth. Are you suggesting it can't get into orbit (elliptical motion around the barycenter)?? $\endgroup$– InnovineNov 21, 2018 at 8:04
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$\begingroup$ An interesting calculation might be whether there is enough water on the Earth to fuel the rocket. I suspect not by an order of magnitude. $\endgroup$– InnovineNov 21, 2018 at 8:12