Space Transport System[NASA] VS Buran [Soviet]

[TheGamingNoobster]

I have read this entire thing so far (like most of us here) and I wondered how a game about short lime-green men has spurred mini flame wars about space planes that are not in service. I do like the points on both sides though. The SLS seems cool but is just NASA trying to get men back into space without bothering the Russians. Keep in mind that this is about the STS and Buran not about STS, Buran and Energia.

Personally I rather the STS due to how I grew up with it. I wanted to fly the shuttle before I could even piece a sentence together. On an entirely different topic, 0.25 soon!

[tater]

The CIA had moles in the KGB:

http://www.theguardian.com/world/2002/oct/13/usa.russia

What makes you think they didn't in the rest of the Russian government as well?

Most of this is still classified, but a while back some records pertaining to this were declassified that revealed several high-ranking Russian officials had been on the CIA payroll. Unfortunately, there's so much unfounded/baseless junk on the internet about the USSR and CIA that it's hard to actually dig up hard facts like that even jsut a handful of year later...

Also, although this has never been conclusively proved, there is a lot of circumstantial evidence that Boris Yeltsin himself may have colluded with the CIA to help break up the USSR (by antagonizing Gorbachev, weakening the power of the Kremlin and central government, and encouraging the Republics to revolt). Of course, he may just have well been playing the CIA in order to advance his own career, and he certainly wasn't an actual CIA agent in any sense. Do bear in mind that his father was an Anti-Soviet, however, so he did harbor some lingering hatred for the USSR and pro-American sympathies...

So no source. Got it.

[Rune]

I have read this entire thing so far (like most of us here) and I wondered how a game about short lime-green men has spurred mini flame wars about space planes that are not in service. I do like the points on both sides though. The SLS seems cool but is just NASA trying to get men back into space without bothering the Russians. Keep in mind that this is about the STS and Buran not about STS, Buran and Energia.

Personally I rather the STS due to how I grew up with it. I wanted to fly the shuttle before I could even piece a sentence together. On an entirely different topic, 0.25 soon!

Because said game got a lot of very geeky, very nice people talking together. And I love these kinds of discussions!

Rune. This is like normal people talking about old sport legends.

[Kulebron]

Roscosmos won't be doing anything useful until Putin is out of leadership. I'm sorry, but the government there is an absolute mess.

Sorry to continue a political discussion, but...

I agree that Roscosmos won't be doing anything useful, and the government is a mess. But changing the leader... Well, Russians are often blamed for wanting a strong leared to solve everything for them. I see the same ideas from westerners who live in functional democracies. Many foreigners, out of sincere sympathy, wish us get a new nice tsar. Unfortunately, wonders never happen.

I can give an example of Obama Cool Aid the Americans have drunk, and then noting that not so much changed. Leaders can contribute to social development and trigger processes, good and bad, but a leader can't turn a whole society upside down. I deal with mayor office and see that where citizens are active, things are under control and gradually improve, whereas if there are only passive dwellers, everything only deteriorates. Same thing on the nation scale. Building a sane society and functional bureacracy takes a lot of time, and even if a better leader comes tomorrow, the results will be long to wait. You can trigger processes, and Putin did his best to destroy civil activity, but importing a new president, government or even democratic procedures like during Perestroika won't work. That time, few cared of them. You have to learn to use them and develop them on the way.

Back on topic: the problem with Roscosmos and the current government is that, unaccountable to the people, they imitate work and fake goals and activity. If you change the president, he may change people for those responsible and honest (which is very unlikely), but then you either have to overhaul the entire government and the agency, or have some intertia and habbits to creep back.

Edited October 6, 2014 by Kulebron

[Northstar1989]

I don't know where you got your figures, but the STS only had a payload capacity of 24 tons to LEO and 16 tons to the ISS. The Orbiter was around 80 tons, which means that the stack actually put 104 tons into LEO. Energia was capable of launching 100 tons into orbit, Buran weighed 75 tons, so that leaves 25 tons of payload.

Your numbers are incorrect. While there are various numbers out there, STS had a cargo bay rated at 29 tons (its nominal capacity was 30-40 tons, but in practice 29 tons was the limit due to its cargo bay). Buran weighed over 80 tons (and could carry its nominal capacity of 30-40 tons, thanks to its heavier cargo bay) and Energyia could lift 175 tons to LEO in its "Vulkan" (8 SRB's + Energia-M upper stage) configuration: the 90-100 ton figure is for its STANDARD configuration (4 SRB's and NO UPPER STAGE).

Here are just two of the many, many articles that prove these figures:

http://www.popularmechanics.com/science/space/rockets/did-the-soviets-actually-build-a-better-space-shuttle-16176311

http://www.k26.com/buran/info/a_comparison/a_comparison.html

That puts both systems in competition with much cheaper alternatives such as Proton, Ariane, or Delta IV Heavy. It simply doesn't make economical sense to use an Energia to launch a 25 ton payload, just like it didn't make sense for NASA to use the Shuttle to launch satellites when you have cheaper rockets available. The orbiters were simply wasted payload capacity.

I'm not disagreeing that the shuttles were wasted capacity. Based on the ability of Energyia to lift 90-100 tons to LEO *with no upper stage* (i.e. as a Two-Stage-To-Orbit with its SRB's, rather than a 3-stage rocket with SRB's), certainly Buran didn't make much economical sense in terms of lift-capacity. Where it REALLY shined, though, was in its cargo return-capacity: up to 15 tons of cargo could safely be returned to the runway by Buran (much like STS). This meant that scientific experiments could be recovered beyond just what could be stuffed into a tiny crew capsule: real life isn't KSP- you can't stuff an unlimited number of experiments into a 1-man pod...

Too bad the Soviets didn't have enough money for a space station program that could really make Buran shine...

The Russians knew this, but because they were paranoid about the US Shuttle's military capabilities, they went with Buran and cancelled their MAKS/Spiral program, which was much more promising.

I don't disagree. The Russian motivations were a bit messed up, and they did cancel quite a few more promising programs to fund Buran. All I said is that it was a superior shuttle system to STS (especially due to the versatility of Energyia)- not that it was a good idea.

Comparing development costs and production costs between capitalist USA and communist USSR is meaningless because the economical systems were totally different. You would have to compare percentages of GDP, headcounts, salaries, facilities... It's a wildly difficult exercice, but what is clear was that the USSR could not afford Buran, therefore it was too expensive.

Saying Russia could not afford Buran is the same as claiming the USA can't afford its space program today. It's a highly-inaccurate representation based on claiming that space exploration is nothing but an exercise in futility... The fact is, Buran could have had hefty scientific benefits for the USSR (if it were used to recover payloads from orbit) the same way STS had hefty scientific benefits for the USA (research performed on STS may soon lead to a biological engineering-based cure for diabetes, for instance). The problem was that the USSR was too inefficient in *OTHER* sectors of its economy to survive, not that Buran was by any stretch of the imagination a waste of money...

Regards,

Northstar

[Northstar1989]

A fuel depot only makes sense if there is demand for frequent payloads beyond LEO. There is no money for payloads and no demand.

There *IS* demand for frequent payloads beyond LEO. It's called Geosynchronous Orbit Communication Satellites.

Beyond that, having an orbit fuel depot would open the door to reusable orbital tugs (which could operate off Nuclear Thermal Engines or Microwave Beamed Power Thermal Rocketry, and thus serve as *much* more cost-efficient to GEO and back...), "atmospheric accumulators" to skim propellant mass (especially O2) off the edge of Earth's upper atmosphere (real-world proposals relied on using Nitrogen-fueled electrical engines for station-keeping), and the launching of manned exploration missions with empty fuel tanks...

Regards,

Northstar

[Northstar1989]

Actually they can't. The US Shuttle could bring up 24 tons of cargo but could only bring down 14 tons. The downmass capability was only used a couple of times until they figured that it really wasn't cost-effective or worth the risk.

Actually, the downmass capacity was used quite frequently to recover scientific experiments from the ISS, as well as several experiments that were performed on the shuttle itself... And I wouldn't call them "not worth the price or risk" when one of those experiments might actually be about to lead to a bioengineering-based cure for Diabetes in the next 10-20 years... (let me know if you want articles on this- I first came across links on that experiment a while back on the Space Labs section of this forum...)

Regards,

Northstar

[Hannu]

I say that STS, because we have real experience of it. It is not fair to compare planned or test specifications of Buran to realized performance of STS. I doubt that there are no space program in the world which have kept its planned specifications and budget and I am sure that if Buran were become to actual use, it would have had more technical and economic problems. Also STS had specifications which were far too optimistic and it was a failure if it is compared to these. However, it was good enough to be in work decades.

[1greywind]

"Which one is better" - define "better".

Edited October 7, 2014 by 1greywind
confused STS and SS, nevermind

[shynung]

There *IS* demand for frequent payloads beyond LEO. It's called Geosynchronous Orbit Communication Satellites.

Beyond that, having an orbit fuel depot would open the door to reusable orbital tugs (which could operate off Nuclear Thermal Engines or Microwave Beamed Power Thermal Rocketry, and thus serve as *much* more cost-efficient to GEO and back...), "atmospheric accumulators" to skim propellant mass (especially O2) off the edge of Earth's upper atmosphere (real-world proposals relied on using Nitrogen-fueled electrical engines for station-keeping), and the launching of manned exploration missions with empty fuel tanks...

GSO satellites today weren't designed for in-orbit refueling, as far as I know. They were designed to stay in one place for a predetermined time (some 15-20 years), and had their delta-v budgets, and therefore their fuel tanks, scaled accordingly.

Also, no NTRs or beamed-power thermal rockets are operational at this point, so it would not make sense to set up a propellant depot for these vehicles.

[Kryten]

There is no demand for 30 tons to GTO, in the same way there is no demand for 100 tons to LEO. Again, there were no payloads funded for energiya except Mir-2 components (most of which were modified Mir backups that already existed) Buran, and Skif. Proton was perfectly adequate for all government payloads to GTO, and still is.

[Rune]

There is no demand for 30 tons to GTO, in the same way there is no demand for 100 tons to LEO. Again, there were no payloads funded for energiya except Mir-2 components (most of which were modified Mir backups that already existed) Buran, and Skif. Proton was perfectly adequate for all government payloads to GTO, and still is.

Yup, in order to grow a market, it has to be scalable. Demand might grow, but first you have to consistently lower the cost, and make everything easily scalable so the whole growth is both sustained and sustainable. A small RLV could see a market growth in mT to LEO, a huge behemoth that expects payloads to materialize in front of it will go rusty and obsolete before someone commits to the scary capital cost of using it.

Rune. Which is not saying that there couldn't be a market. Not at all.

[Northstar1989]

GSO satellites today weren't designed for in-orbit refueling, as far as I know. They were designed to stay in one place for a predetermined time (some 15-20 years), and had their delta-v budgets, and therefore their fuel tanks, scaled accordingly.

You're not listening to what I'm writing, at all.

What I SAID was that you could launch the satellites, and their transfer stages to GTO, empty. You would then fill them up with their transfer-stage and station-keeping fuel BEFORE sending them to GSO for the first time. Obviously, this would require a slight re-design of satellites to allow them to be fueled up in-orbit...

There was no discussion of refueling satellites AFTER they had already reached GSO with additional station-keeping fuel, and unless we could find a way of getting fuel to LEO or GSO cheaper (such as LEO atmospheric-accumulators, Lunar IRSU fuel production with a reusable transfer infrastructure to LEO/GEO, or higher-ISP propulsion systems reducing the overall needed fuel mass), it probably wouldn't make economic sense...

Also, no NTRs or beamed-power thermal rockets are operational at this point, so it would not make sense to set up a propellant depot for these vehicles.

Nuclear Thermal Rocket tugs have been technologically viable since the 1970's. Although an entirely DIFFERENT issue than setting up LEO/GSO fuel depots (which work just fine with specialized high-efficiency, low-cost tankers: which could also be much less reliable than those lifting expensive payloads, for big cost-savings, via the Big Dumb Booster and Aquarius concepts of the exponential relation between engineering margins and reliability in rocketry and cost...), they do benefit strongly from having them already in operation. They can use some of the same propellants as chemical rockets (H2 or Methane), and simply get better Specific Impulse from them.

Also, a single reusable Nuclear (or with modern technology, Microwave-powered) Tug could replace the cost of launching potentially DOZENS of single-use GSO transfer stages, leading to large cost savings- especially if those transfer stages were refuelable upon first reaching LEO, which would add significantly to their cost (even while greatly bringing down overall mission cost, as the fuel could then be launched on much cheaper launch vehicles... Aquarius rockets could achieve launch costs less than 1/20th current costs-per-kg, for instance: though at the cost of a 33% launch failure rate...)

Regards,

Northstar

[SkyHook]

It's very scary how anything we do..the Russians either do it first, or do it better. Make no mistake about it, Buran would have been superior. Wouldacouldashoulda doesn't fly in the real world though!

[Kryten]

Replacing mass-reduced transfer stages and frequent launches with a complex tug and infrequent giant launches is hardly a compelling economic prospect; you're restricted by demands of different customers (Arianespave has trouble as it is just matching two satellites per launch), you have much higher maintenance costs due to your larger and more complex infrastructure, and-by the far the worst aspect-you've almost completely eliminated gains from economy of scale. Really, it's like you missed the entire point of the Aquarius proposal.

[Nibb31]

It's very scary how anything we do..the Russians either do it first, or do it better. Make no mistake about it, Buran would have been superior. Wouldacouldashoulda doesn't fly in the real world though!

"We" is a relative term when you're on an international forum with members from all over the World, including from China and Russia...

And Buran threw away an entire Energia rocket on each launch, including 4 Zenit cores and 4 RD-0120 engines. No way would it ever have been economical. It's as if NASA threw away a Saturn V for each Shuttle launch.

[montyben101]

http://en.m.wikipedia.org/wiki/Saturn-Shuttle

Seriously it was a real idea once

[Northstar1989]

Replacing mass-reduced transfer stages and frequent launches with a complex tug and infrequent giant launches is hardly a compelling economic prospect; you're restricted by demands of different customers (Arianespave has trouble as it is just matching two satellites per launch), you have much higher maintenance costs due to your larger and more complex infrastructure, and-by the far the worst aspect-you've almost completely eliminated gains from economy of scale. Really, it's like you missed the entire point of the Aquarius proposal.

You're not listening to the arguments I made again.

The whole problem with larger launches in launching satellites is that you have trouble matching multiple satellites into a single launch. However when using a large launcher to lift a single monolithic payload (like 100 tons of hypergolic fuel to LEO), you don't have that problem at all...

What you DO have is the Delta-V advantages of larger rockets (larger rockets require less Delta-V to make orbit because they lose less Delta-V to atmospheric drag, due to their better ballistic coefficients...) as well as the cost and mass-savings of needing fewer total control/guidance systems (the recurring cost of building a control/guidance system for a single 100 metric ton lifter will be a lot cheaper than four separate control/guidance systems each rated for a 25 metric ton payload-capacity rocket, and four guidance systems are heavier than one...)

The points of Aquarius were two-fold: one was to take advantage of mass-production of rocket parts and simply build lots of small lifters (like I said before, you will NOT benefit from mass-production when you are talking 25 vs. 100-ton lifters), the other was to build rockets to much looser engineering and reliability standards (which would hurt rocket reliability, but save a lot more on the costs of actually building the rocket- which would allow you to more than afford to compensate for the failures by launching !MOAR! cheap/unreliable rockets for cheap/easily-replaced payloads, such as fuel...)

Aquarius also would have benefited from making aquatic launches (hence the name) rather than land-based launches, but that's another story...

As for the nuclear tug, it would have greatly reduced the mass you need to launch to orbit in the first place- and is entirely separate from using large, Big Dumb Boosters to launch huge payloads of fuel into orbit in monolithic Sea Dragon style aquatic launches (THIS style of Big Dumb Booster is still highly reliable- just built with looser engineering standards AND much greater safety margins...) or using something like the Energyia rocket instead.

Speaking of which, back to the topic at hand- the whole point I was making is that Energyia is superior because for a fraction of the development cost of the Space Shuttle, they also got a Heavy Launch Vehicle with a greater payload capacity than the up-and-coming SLS out of the deal... All you had to do was rip off Buran, add an upper stage, double the number of liquid-fueled radial boosters (Energyia was specifically built to allow for all these modifications) and you could easily lift 175 tons into Low Earth Orbit. And, it was a highly-reliable rocket, nothing like Aquarius- which meant you could also use it for manned missions to Mars, or even to construct a long-term Moon base...

Regards,

Northstar

[shynung]

You're not listening to what I'm writing, at all.

Please enlighten me on how am I supposed to listen to something that should be read.

What I SAID was that you could launch the satellites, and their transfer stages to GTO, empty. You would then fill them up with their transfer-stage and station-keeping fuel BEFORE sending them to GSO for the first time. Obviously, this would require a slight re-design of satellites to allow them to be fueled up in-orbit...

There was no discussion of refueling satellites AFTER they had already reached GSO with additional station-keeping fuel, and unless we could find a way of getting fuel to LEO or GSO cheaper (such as LEO atmospheric-accumulators, Lunar IRSU fuel production with a reusable transfer infrastructure to LEO/GEO, or higher-ISP propulsion systems reducing the overall needed fuel mass), it probably wouldn't make economic sense...

Ah, now I see your point. Though, to be fair, we're simply splitting the delta-v requirements here, launching the vehicle and fuel on different rockets (fleets of Aquarii, anyone?). Sure, we can do ISRU and get the fuel elsewhere, but there's the problem of developing the necessary hardware (of which I have not known any of them operational), and getting it out to where we need it.

Nuclear Thermal Rocket tugs have been technologically viable since the 1970's. Although an entirely DIFFERENT issue than setting up LEO/GSO fuel depots (which work just fine with specialized high-efficiency, low-cost tankers: which could also be much less reliable than those lifting expensive payloads, for big cost-savings, via the Big Dumb Booster and Aquarius concepts of the exponential relation between engineering margins and reliability in rocketry and cost...), they do benefit strongly from having them already in operation. They can use some of the same propellants as chemical rockets (H2 or Methane), and simply get better Specific Impulse from them.

Also, a single reusable Nuclear (or with modern technology, Microwave-powered) Tug could replace the cost of launching potentially DOZENS of single-use GSO transfer stages, leading to large cost savings- especially if those transfer stages were refuelable upon first reaching LEO, which would add significantly to their cost (even while greatly bringing down overall mission cost, as the fuel could then be launched on much cheaper launch vehicles... Aquarius rockets could achieve launch costs less than 1/20th current costs-per-kg, for instance: though at the cost of a 33% launch failure rate...)

The problem with nuclear thermal engines isn't technological, but political. To sum up, there's a deep negative stigma about launching anything nuclear these days (even earthbound nuclear power plants), that the space agencies capable of doing so (NASA, in particular) are simply unwilling to do it. Get this political view out of the window, and nuclear engines would have been as common as LV-Ns in KSP players' crafts.

As for microwave thermal engines, I have not seen or heard any working, flight capable specimens. As soon as one comes out, we may then be able to assess its capabilities on orbit-to-orbit missions such as transfer stages. For now, we can only stick to chemical engines, and hope the people at NASA making space nuclear reactor (and Ad Astra, for good measure) will make something useful in the near future.

Anyway...

http://en.m.wikipedia.org/wiki/Saturn-Shuttle

Seriously it was a real idea once

Cool! Get me my flight jacket, I want to fly it.

Edited October 10, 2014 by shynung

[Northstar1989]

Ah, now I see your point. Though, to be fair, we're simply splitting the delta-v requirements here, launching the vehicle and fuel on different rockets (fleets of Aquarii, anyone?). Sure, we can do ISRU and get the fuel elsewhere, but there's the problem of developing the necessary hardware (of which I have not known any of them operational), and getting it out to where we need it.

Or, you could use an Energyia rocket to launch the fuel. Without the docking hazard of sending a million small rockets to the orbital fuel depot, and for less Delta-V than the small rockets would have consumed. Giving Energyia an actual, real use besides just launching the Buran shuttle or Mars/Moon-base missions... Which was kind of my point here...

The problem with nuclear thermal engines isn't technological, but political. To sum up, there's a deep negative stigma about launching anything nuclear these days (even earthbound nuclear power plants), that the space agencies capable of doing so (NASA, in particular) are simply unwilling to do it. Get this political view out of the window, and nuclear engines would have been as common as LV-Ns in KSP players' crafts.

We've probably gotten too far off topic if we're talking about nuclear politics on a Buran/STS thread. My point was just mainly that Energyia could be used for efficiently launching large quantities of fuel to orbital fuel depots, and fuel depots add value to reusable nuclear tugs (which otherwise have to dock directly with a fuel tanker every time they need refueling- which is inefficient if the tug doesn't need a full fuel load for a given mission, but the tanker is designed to carry a full fuel-load for the tug...)

As for microwave thermal engines, I have not seen or heard any working, flight capable specimens. As soon as one comes out, we may then be able to assess its capabilities on orbit-to-orbit missions such as transfer stages. For now, we can only stick to chemical engines, and hope the people at NASA making space nuclear reactor (and Ad Astra, for good measure) will make something useful in the near future.

Microwave Thermal is better than nuclear. Better because you can actually achieve the same specific impulse (700-1000s with Liquid Hydrogen) for a lot *less* engine-mass (you don't have to push around a heavy nuclear reactor), without any of the political hazards of launching something nuclear to orbit...

And since the tangent-train has clearly already run the station...

Microwave Thermal may not have any working flight-prototypes (although the related craft of a Lightcraft *has*), but it's been the subject of countless feasibility and engineering studies proving it is a realistic option, as well as a LOT of media attention:

http://core.kmi.open.ac.uk/download/pdf/4871859.pdf

http://www.cnet.com/news/rocket-scientist-aims-to-relaunch-propulsion-technology/

http://physics.le.ac.uk/journals/index.php/pst/article/view/190/106

http://www.astrobio.net/news-exclusive/beaming-rockets-into-space/

http://callcenterinfo.tmcnet.com/news/2011/04/30/5477779.htm

http://nextbigfuture.com/2011/05/beam-powered-space-propulsion-work-from.html

Note the first link in particular, which calculates an actual ascent trajectory for a Microwave Thermal Rocket easily within the reach of current technology...

Regards,

Northstar

Edited October 13, 2014 by Northstar1989

[shynung]

Or, you could use an Energyia rocket to launch the fuel. Without the docking hazard of sending a million small rockets to the orbital fuel depot, and for less Delta-V than the small rockets would have consumed. Giving Energyia an actual, real use besides just launching the Buran shuttle or Mars/Moon-base missions... Which was kind of my point here...

An Energiya rocket designed for bulk fuel delivery? Seems promising, although I had to admit that today's heavy-lift rockets could do the same thing just as effectively.

Of particular note, one could send a full fuel tank into orbit, equipped with small and efficient engines, some solar panels, and some unmanned craft avionics, in order to do stationkeeping. Other spacecrafts with further destinations could launch unfueled, dock with this flying fuel tank (an orbital support vehicle, as I called it) and take their fuel from there. A single OSV, if large enough, can support multiple outbound spacecraft before running out of stored fuel, and can be simply deorbited later.

We've probably gotten too far off topic if we're talking about nuclear politics on a Buran/STS thread. My point was just mainly that Energyia could be used for efficiently launching large quantities of fuel to orbital fuel depots, and fuel depots add value to reusable nuclear tugs (which otherwise have to dock directly with a fuel tanker every time they need refueling- which is inefficient if the tug doesn't need a full fuel load for a given mission, but the tanker is designed to carry a full fuel-load for the tug...)

I'd rather not talk about nuclear politics here (in fact, I hate politics), but in reality, it's difficult to launch a nuclear space tug without provoking the ire of certain people. Yes, I agree that reusable fuel depots and nuclear space tugs would be incredibly useful in intensive space missions, but some people (not me) doesn't like the idea of using nuclear energy to power our spacecraft (or indeed, anything at all). That's one of the reasons solar-electric propulsion is currently being developed as well; to get around this anti-nuclear dogma.

Although, Ad Astra did say that their more powerful electric engines would require onboard nuclear reactors (their energy consumption is quite significant), so I think the anti-nuke dogma will disappear eventually.

Microwave Thermal is better than nuclear. Better because you can actually achieve the same specific impulse (700-1000s with Liquid Hydrogen) for a lot *less* engine-mass (you don't have to push around a heavy nuclear reactor), without any of the political hazards of launching something nuclear to orbit...

And since the tangent-train has clearly already run the station...

Microwave Thermal may not have any working flight-prototypes (although the related craft of a Lightcraft *has*), but it's been the subject of countless feasibility and engineering studies proving it is a realistic option, as well as a LOT of media attention:

http://core.kmi.open.ac.uk/download/pdf/4871859.pdf

http://www.cnet.com/news/rocket-scientist-aims-to-relaunch-propulsion-technology/

http://physics.le.ac.uk/journals/index.php/pst/article/view/190/106

http://www.astrobio.net/news-exclusive/beaming-rockets-into-space/

http://callcenterinfo.tmcnet.com/news/2011/04/30/5477779.htm

http://nextbigfuture.com/2011/05/beam-powered-space-propulsion-work-from.html

Note the first link in particular, which calculates an actual ascent trajectory for a Microwave Thermal Rocket easily within the reach of current technology..

I can only hope their research will yield something very useful within my lifetime, and that I get to ride in whatever vehicle they strap the engine to.

[Sky_walker]

Of particular note, one could send a full fuel tank into orbit, equipped with small and efficient engines, some solar panels, and some unmanned craft avionics, in order to do stationkeeping.

It'd be more efficient to simply send a whole upper stage there instead of a separate fuel tank.

Yes, it'd require separate design, but could be cheaper and less risky in a long term.

Other spacecrafts with further destinations could launch unfueled, dock with this flying fuel tank (an orbital support vehicle, as I called it) and take their fuel from there. A single OSV, if large enough, can support multiple outbound spacecraft before running out of stored fuel, and can be simply deorbited later.

What you propose is relatively risky and requires a lot of changes to the procedures, creating new docking ports that allow fuel transfers, etc. . Even if such fuel depot would be creates - there still would be plenty of spacecrafts launching with all the fuel supply they need. And depot cannot stay in space for too long due to fuel degradation... so there we go - you just re-discovered the reason why no fuel depots exist on an orbit as of today.

Although, Ad Astra did say that their more powerful electric engines would require onboard nuclear reactors (their energy consumption is quite significant), so I think the anti-nuke dogma will disappear eventually.

Doubtful.

You'd think that super-safe modern nuclear reactors would negate anti-nuke dogma, but then one of the oldest reactors on the globe got an accident - Fukushima - and suddenly whole dogma comes out again.

And that's the reactor sitting in land, not flying over people's head

[shynung]

It'd be more efficient to simply send a whole upper stage there instead of a separate fuel tank.

Yes, it'd require separate design, but could be cheaper and less risky in a long term.

That full fuel tank could be an entire upper stage without the engine. Of course, having engines onboard means the upper stage can now push other spacecrafts around (and be a tug itself in the process).

What you propose is relatively risky and requires a lot of changes to the procedures, creating new docking ports that allow fuel transfers, etc. . Even if such fuel depot would be creates - there still would be plenty of spacecrafts launching with all the fuel supply they need. And depot cannot stay in space for too long due to fuel degradation... so there we go - you just re-discovered the reason why no fuel depots exist on an orbit as of today.

Does hypergolic fuels degrade with time?

Anyway, being used to KSP with fuel-transfer-capable docking ports, I realize that the concept would need to be adapted to current conditions, maybe even significantly. However, I don't think it would be long before someone established a safe way to transfer fuel between spacecrafts.

Or, one could go with the simpler way, docking a fully-fueled spacecraft with a waiting fully-fueled transfer stage, and use the transfer stage to push the spacecraft to where it needs to go

Doubtful.

You'd think that super-safe modern nuclear reactors would negate anti-nuke dogma, but then one of the oldest reactors on the globe got an accident - Fukushima - and suddenly whole dogma comes out again.

And that's the reactor sitting in land, not flying over people's head

Wasn't it like that when the steam engine first came out? People were afraid of fire and boiler explosions these things occasionally cause, but it was widely used in the end anyway.

I still think that the anti-nuke dogma will disappear eventually, for the energy demand will inevitably rise along with the population. I'm not sure how long are we supposed to wait, though; we might as well be nonexistent when nuclear power is finally widely accepted.

[magnemoe]

Doubtful.

You'd think that super-safe modern nuclear reactors would negate anti-nuke dogma, but then one of the oldest reactors on the globe got an accident - Fukushima - and suddenly whole dogma comes out again.

And that's the reactor sitting in land, not flying over people's head

Main problem with Nerva is lack of missions, nerva or something better is pretty much required for manned Mars missions or other huge deep space projects.

Would be an benefit for some deep space missions but not enough to restart development so far.

LV-N is not the best engine for small probes in KSP either.

An reusable high ISP tug would be useful for going to the moon.

It would also be beneficial for GEO if lightweight so you would save plenty of weight getting where and this is the only commercial marked today.

Both would require significant infrastructure.

Russia has no problems with western special interest groups so the anti-nuke movement is not a factor for them.

[Sky_walker]

That full fuel tank could be an entire upper stage without the engine. Of course, having engines onboard means the upper stage can now push other spacecrafts around (and be a tug itself in the process).

That's nowhere near important as being able to deorbit itself.

Does hypergolic fuels degrade with time?

Important problem with hypergolics is their toxicity which makes keeping them under control in a long term very challenging. But yes, they do degrade over time. Like pretty much everything (each fuel type got it's own "weak point", a reason why it can't really be stored in large amounts for years in space, though obviously some are safer than other). Question is - if you can use the fuel before it expires. If there's enough demand - fuel degradation wouldn't be much of a problem. However currently there isn't. We'd have to regularly go beyond LEO with manned spacecrafts to create such demand - and as of now we're nowhere near that point. (And an eve of electric propulsion for satellites pretty much negates the need for refuelling. We're reaching the point where a fault to the satellite hardware is likely to occur than it running out of fuel - hence satellites grow bigger and bigger: to have redundant equipment onboard).

Anyway, being used to KSP with fuel-transfer-capable docking ports

KSP got no relevance to the real life. Read my signature.

I realize that the concept would need to be adapted to current conditions, maybe even significantly. However, I don't think it would be long before someone established a safe way to transfer fuel between spacecrafts.

Or, one could go with the simpler way, docking a fully-fueled spacecraft with a waiting fully-fueled transfer stage, and use the transfer stage to push the spacecraft to where it needs to go

I'd suggest you read through that for a good start: https://en.wikipedia.org/wiki/Propellant_depot#Engineering_design_issues

Wasn't it like that when the steam engine first came out? People were afraid of fire and boiler explosions these things occasionally cause, but it was widely used in the end anyway.

Only difference being that steam contamination doesn't last years.

That's why people are afraid of nuclear powerplants. Not because they can kill people here now, but because of long-term consequences. (And before you try to defend against it - I know, and I very much agree that nuclear powerplants are a way to go).

I still think that the anti-nuke dogma will disappear eventually,

You mean like an anti-machine dogma disappeared? Oh, wait... people are still pissing their pants over "robots" taking over their jobs. Nothing changed since XIX century.

for the energy demand will inevitably rise along with the population. I'm not sure how long are we supposed to wait, though; we might as well be nonexistent when nuclear power is finally widely accepted.

Yea, just like GMO plants, which are also a response to the raising populations.... *eyerolls*

Humans are really bad in thinking on a global scale.

Edited October 13, 2014 by Sky_walker