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Spaceplane or rocket family?


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What philosophy for a reliable launch infrastructure would you pick?  

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  1. 1. What philosophy for a reliable launch infrastructure would you pick?

    • Spaceplane
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    • Rocket family
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Let's say NASA's budget is doubled tomorrow.

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How everyone would react if that happened.

Just as importantly, NASA is given a clearer vision: Develop the launchpad-to-orbit infrastructure required to make all desired future missions (Skylab II, Moon landing, asteroid mission, Mars manned mission etc.) possible, within a decade. This means an extremely capable launch system. The thing is, they are not told exactly what they have to do, they can accomplish this goal how they wish.

If you asked me this question two days ago, then I would almost certainly have said the only way to have an effective launch infrastructure is via a 100% reusable spaceplane.

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Bare in mind, I am not talking about something like the Space Shuttle. The Shuttle we all knew and loved was the "cheaper" option, that has a lower development cost, but ended up costing more in maintenance. The "spaceplane" I'm talking about could launch under it's own power, from a runway, go to orbit, do it's job, then come back down to land at the same runway. And do it again a few days later.

For the purposes of the question, I'll assume NASA takes a look at what Reaction Engines is doing, ans bases their spaceplane concept on Skylon. That means similar specs-15 tonnes to LEO, 3 day turnaround-time, cost-per-kilogram of payload down 1 or 2 orders of magnitude.

Like I said, two days ago, I would've been bought entirely by the spaceplane idea. Then I heard what Neil deGrasse Tyson would tell NASA to do if the budget was doubled. He suggested developing a whole family of rockets, with a system of stretched variants and side-boosters, that can perform any mission profile you want.

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Not many people have family photos this beautiful.

Need a satellite in orbit? Done. Interplanetary space probe? Done. Crew transfer to a space station? Done. Need to launch a space station? Done. Asteroid coming our way, and we need people on it to set up a mass-driver to push it away? Done. Manned Mars mission? Done.

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What would you choose? Both have their merits, and I would sell my soul to see either happen.

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Let's say NASA's budget is doubled tomorrow.

-snip-

How everyone would react if that happened.

True that :D

To be honest, It depends what type of rocket we are talking about, if we are talking about a reusable rocket then i would have to say rockets. but if we are talking about old conventional non-reusable rocket, than I would have to pick the spaceplanes...

EDIT: Welp, accidentally voted for spaceplanes :P

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I'd go for rockets. The problem with spaceplanes is that you're pretty limited in terms of staging due to aerodynamics being a bitch. So your payload to mass fraction goes to ****.

Rockets have better payload capacity, are a proven concept and are simpler to build (And thus less error prone). The main selling point for a spaceplane is that its reusable and thus cheaper. But to offset the initial cost and maintenance you need to do a lot of launches. And mass production of single use rockets also lessens the cost per rocket. Not to mention you can make rockets that are (partly) reusable. So rockets are an all around better choice imo.

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All missions 'desired' by whom exactly? The only current sources for desired missions are congress and the decadal survey. The former want an asteroid mission, and the latter aren't any more ambitious than asking for mars sample return and a europa probe. There are no requirements for a large family of launchers, and there aren't enough launches on the cards for a reusable spaceplane to be remotely viable.

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All missions 'desired' by whom exactly? The only current sources for desired missions are congress and the decadal survey. The former want an asteroid mission, and the latter aren't any more ambitious than asking for mars sample return and a europa probe. There are no requirements for a large family of launchers, and there aren't enough launches on the cards for a reusable spaceplane to be remotely viable.

Not as true as you might think - at present, the waitlists for commercial launch slots tend to be years long, due to the infrequency of said launches and the number of people who realize that space is valuable for scientific/commercial purposes. I anticipate space, especially LEO, becoming more commercialized within the next 15-20 years, which means that, unless something changes, they will grow longer and longer. Hence either the reusable rocket or a viable SSTO spaceplane.

As for who, it runs the gamut - universities and private research institutions, corporations, and governments. With the advent of the CubeSat thing, there's even private individuals of (relatively) modest means who are putting objects in orbit.

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For NASA... a rocket family, given they're leaving routine stuff to private companies. I'm very much behind Skylon because it's about time my country got behind something really big like that ( I can't even remember the last prestige aerospace project... Concorde maybe? ), but NASA doesn't need a spaceplane; it's not much use for space exploration. If they want a cheap way to launch small probes they could just rent a Skylon launch slot anyway. It's the big stuff they can't rent a slot for - and nobody other than exploration programs need - and that's why they'd want a custom lift platform.

NASA could offer themselves as commercial consultants if they want outside income, they don't necessarily need to provide commercial hardware.

Edited by Van Disaster
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Neither rockets or spaceplanes. Leave the "getting off the ground" to the private sector and concentrate on space missions.

It has yet to be proven that a reusable SSTO is feasible economically let alone technically. We have had this discussion hundreds of times already: There is no demand for a launch rate that would justify the upfront investment of a reusable SSTO, and launch rates are not going to decrease until launch costs come down drastically. It's a chicken and egg problem, and although a reusable SSTO might reduce the hardware cost of a single launch, that unit hardware cost represents only a small fraction of the cost of an orbital launch. And NASA will never fund Skylon. The main purpose of NASA is to fund domestic jobs, not to buy technology from a UK company.

I would rather see NASA concentrate on actual spacecraft rather than launchers. Rockets are a well understood technology and the private sector has decades of experience designing, building, and operating them. Current commercial launchers are perfectly capable of launching stuff into orbit for a fraction of the cost of SLS. We could have humans on the Moon with 2 or 3 Falcon Heavy or Delta Heavy launches for a fraction of the cost of SLS.

NASA's mission should be Research and Development, so I would like to get them back to developing exploration and technologies for living in space. If I had my way.

- Develop a permanently (or semi-permanently) manned lunar outpost, akin to the Scott-Amundsen Polar Station in Antarctica.

- Develop a reusable lunar shuttle/lander that would transit from LEO to the lunar surface on a single fill of propellant. Refuel it and rotate crew in LEO with a Dragon 2.

- Use the outpost to develop techniques for long duration stays, study the effects of partial gravity and cosmic rays, develop ISRU, heavy robotics, hydroponics, and closed-loop life support techniques.

- Outsource the launches for all that stuff to ULA, SpaceX or even Arianespace.

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Not as true as you might think - at present, the waitlists for commercial launch slots tend to be years long, due to the infrequency of said launches and the number of people who realize that space is valuable for scientific/commercial purposes. I anticipate space, especially LEO, becoming more commercialized within the next 15-20 years, which means that, unless something changes, they will grow longer and longer.

I think you have that backward. Commercialization means that waitlists will be shorter, as more providers will enter the market, and those that are already here will be able to launch much more frequently. The private market has a tendency to reduce wait times in general.

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A question you should ask yourself before doing something is why are you doing it. There is no practical reason to make a Space Plane. While often given the name "reusable" space planes are not reusable, even if you could fly it up on it's own power (you can't) the underbelly heat tiles would have to be replaced every-time it lands, which is time consuming, expensive, and dangerous if done incorrectly. This along with many other checks and safety protocol that comes with reusable designs makes space planes expensive, and even more importantly stupidly dangerous. Whats more stupid than going up on 100s of tons of explosives? Coming down on a 30 year old chassis that may or may not of been maintenance properly after going up on 100s of tons of explosives. The best way to solve a problem is the simplest one. Metal is not hard to find, nor fuel expensive, nor rocket stages hard to make.

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All missions 'desired' by whom exactly? The only current sources for desired missions are congress and the decadal survey. The former want an asteroid mission, and the latter aren't any more ambitious than asking for mars sample return and a europa probe. There are no requirements for a large family of launchers, and there aren't enough launches on the cards for a reusable spaceplane to be remotely viable.

From his post he seems to mean "every mission ever flogged by every fanboy who ever got access to a keyboard". Which isn't, as he calls for elsewhere, a "clearer vision". It's a mish-mash that will take much longer than the decade specified and cost much more than the doubled budget also specified.

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I'd go for rockets. The problem with spaceplanes is that you're pretty limited in terms of staging due to aerodynamics being a bitch. So your payload to mass fraction goes to ****.

Reaction engines boast that Skylon ought to be able to achieve a better mass fraction than any conventional rocket - though I have serious doubts about how accurate their analysis is. Still, there is the possibility that they have reason to make that claim, in which case it is an extremely interesting one indeed!

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Neither rockets or spaceplanes. Leave the "getting off the ground" to the private sector and concentrate on space missions.

If you limit yourself only to private boosters otherwise available, you end up being limited mostly to boosters optimized for delivery of heavy commsats to GEO/GSO. (And not being capable of being man-rated.) If you specify the booster capabilities (As NASA really needs to) and hire a commercial company to build it, you end up paying through the nose because of the relatively low launch rate. (This is more or less where we are today.)

Thus, the 'common component' booster family is not without advantages if you want a wide(ish) range of boosters for a variety of missions.

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If you limit yourself only to private boosters otherwise available, you end up being limited mostly to boosters optimized for delivery of heavy commsats to GEO/GSO. (And not being capable of being man-rated.) If you specify the booster capabilities (As NASA really needs to) and hire a commercial company to build it, you end up paying through the nose because of the relatively low launch rate. (This is more or less where we are today.

That's true, but it's perfectly possible to design a Moon mission on EELV launchers. You might need 3 launches instead of 2, but using off-the-shelf hardware will always be cheaper than designing a whole new series of heavy-lift rockets for only a handful of launches.

Any hardware that belongs to NASA cannot be used for commercial purposes, so NASA rockets suffer from the same problem. SLS simply can't be used for anything else than the handful of exploration launches that are envisioned. The commercial sector has no use for it, and even if they did, NASA wouldn't be allowed to sell it to them.

Thus, the 'common component' booster family is not without advantages if you want a wide(ish) range of boosters for a variety of missions.

We pretty much agree here. If you want some economies of scale (which is the only way to bring cost down), you need as much commonality as you can get between commercial and government launches. I think Dragon Heavy and Delta Heavy, with their modular designs, are on the right track.

NASA should be working on Altair, DSH, actual payloads and mission hardware, instead of spending all they've got on SLS. Payloads can be sent up on smaller rockets and assembled in orbit for a fraction of the development cost of SLS.

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Payloads can be sent up on smaller rockets and assembled in orbit for a fraction of the development cost of SLS.

Which doesn't come cheaply by any measurement - it adds to the costs because you've made everything more complicated, and it adds to the weight and volume launched because every segment needs support (power, cooling, attitude control, etc...), it increases the programmatic risk sharply (not only because of the increased number of launches, but also due to the increased complexity and on-orbit assembly steps). And it does so for each and every mission launched and assembled this way, it's not a one-time cost.

It's not nearly the black-and-white tradeoff you make it out to be.

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Which doesn't come cheaply by any measurement - it adds to the costs because you've made everything more complicated, and it adds to the weight and volume launched because every segment needs support (power, cooling, attitude control, etc...), it increases the programmatic risk sharply (not only because of the increased number of launches, but also due to the increased complexity and on-orbit assembly steps). And it does so for each and every mission launched and assembled this way, it's not a one-time cost.

It's not nearly the black-and-white tradeoff you make it out to be.

I agree, but in turn those items, avionics computers, attitude control, docking adapters, also benefit from economies of scale. The Russians benefited from economies of scale by series production of common elements (TKS, DOS, Proton, Soyuz...) instead of building a super duper launcher to launch it all in one flight.

The cost of the NDA/SIMAC will come down if NASA builds dozens of them instead of 2 or 3. You could also make the orbital tug part of the launch deal, like a smarter disposable upper stage similar to the way Kvant-1 was added to Mir, or something based on ATV or Cygnus. It would be like a COTS plan on steroids but for 20-40 ton payload modules instead of pressurized cargo.

I agree, it adds complexity and has a weight penalty, but the cost of developing a whole new launcher with infrastructure, maintenance and manufacturing facilities for 10 launches over a 20 year period is crazy. SLS is going to suck up all of NASA's budget even more than STS did, and they will never have any money for the actual missions. Using private launch contractors allows commonalities with existing launchers and allows to share the investment with commercial and DOD launch requirements.

I don't think it's black and white, but I still think it's economically pretty clear cut. But more importantly, it forces NASA to concentrate on advancing the state-of-the-art in space technology and biology, which was supposed to be its primary mandate, instead of building yet another booster.

Edited by Nibb31
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I think this whole idea of continuing to launch exploration missions from earth is bunk frankly. We need to get a production center in space as fast as possible, if you could build your ship on the surface of the moon even you would bring a mars mission cost down by a factor of 10 not 1 or 2. If we are ever going anywhere in space we will do this so why wait, and if we are not going anywhere in space can they just start WWIII already so I can see some real fireworks.

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I think this whole idea of continuing to launch exploration missions from earth is bunk frankly. We need to get a production center in space as fast as possible, if you could build your ship on the surface of the moon even you would bring a mars mission cost down by a factor of 10 not 1 or 2.

To build all that space infrastructure, you're still going to need some heavy-lifting to get all that manufacturing hardware into space. The effort would eat up all NASA's space budget for the next 30 years at least (if it somehow managed to survive more that 6 administrations without being cancelled or derailed). That would be 30 years without any space exploration at all, because you would argue that there's no point in launching stuff from Earth. It's simply not realistic as a short or medium term goal.

I'd rather we work on goals that are actually achievable rather than fuel pipe dreams that have zero chance of ever happening.

If we are ever going anywhere in space we will do this so why wait, and if we are not going anywhere in space can they just start WWIII already so I can see some real fireworks.

If you are convinced that our "destiny" is to explore and expand (I personally don't believe in "destiny"), then what difference does it make if we achieve that goal in 2000 years rather than in 50 years. There is no rush, Humanity has been around for hundreds of thousands of years, so a couple of centuries more or less doesn't make a difference.

Let's do what we can do, and not try to run and leap when we hardly have any experience standing on two feet.

Edited by Nibb31
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I dont know what NASA would go for but I know what I would like to see some one do, NASA or other organization/company. Spaceplane!

Its about time Space exploration became reusable and environmental friendly. Sure you can argue all you want that it has little or no effect but solid boosters are not the most friendly once and trashing the ocean with valuable metals is just a waste even if its just a fraction its a waste.

Hydrogen Powered spaceplane would be extremely friendly to the environment and fit with what humans are trying to do on all other sectors, make our way of live having less of an environmental impact. Re-usability and a friendly fuel goes a long way.

Im not saying rockets should be band just that if there was a spaceplane like the skylon it could do a big portion of the normal jobs and leave the more demanding once to rockets.

It would also be nice to see what effect a reusable spaceplane like the skylon would have one the exploration of space and the space industry and the technology that would need to be invented to make the first spaceplane. Might be a failure or spawn new businesses and science. Im not much for, ooh no one has done a spaceplane so we dont know if it works jada jada. Well some one probably sad the same about going to the moon in a rocket once. Lucky for use no one listened to them. If NASA or some on else gets the funding for a spaceplane it will be built and refined until it works.

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Spaceplanes need development and we should do that! Sometimes changing the path taken can lead to new unexpected developments. Spaceplanes could become a new faster way then flying. And because you're out of the atmosphere during the majority of the flight you're not polluting.

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The worlds best bet for this right now is Space X. Simply, once they have all of the falcon rockets functional and reusable, then we will be truly set for our advancements into space, as well as privatization. This will certainly happen long before the development and finishing of the Skylon. And if the Skylon works, then perhaps rockets may use it's reaction engines to power rocket launch stages.

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The advantage that SpaceX has over Skylon is that it's funded by an eccentric billionaire who believes wholeheartedly in the advancement of humanity in space. If Elon Musk put his money behind Skylon, it would be flying two years from now.

That being said, though, the Falcon family of rockets is looking VERY promising for dropping launch costs.

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I personally see spaceplanes as cheaper, safer, more reliable, and more effective (assuming the technology was perfected, like rockets) for satellite launches, crew rotation, and basic orbiters. As for any kind of heavy lifting, leave it to the rocket families. Using the spaceplanes for the light work is great as then you can reliably make rockets without even considering small satellite and crew payloads. That would put your G-force tolerance higher, your minimum capacity higher and thus more development budget to the higher end, and eliminate the need for smaller rocket family components. That said, spaceplanes are not as polished as rocket families and thus would lend more light work to the rockets, reducing the R&D that could be done on the heavy lift side.

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The advantage that SpaceX has over Skylon is that it's funded by an eccentric billionaire who believes wholeheartedly in the advancement of humanity in space. If Elon Musk put his money behind Skylon, it would be flying two years from now.

That being said, though, the Falcon family of rockets is looking VERY promising for dropping launch costs.

The advantage that SpaceX has is that they have government backed contracts, and they're using current technology.

Having said that, the UK govt is a Reaction Engines shareholder now.

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