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#1 2018-07-14 17:18:04

Yuri Pilipishin
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From: Lviv, Ukraine
Registered: 2017-05-21
Posts: 26
Website

Some objections concerning the Elon Musk's Martian project

Hi all.

I have some objections concerning the Elon Musk's Martian project. It seems, it wouldn't even be possible to reach Mars, using Elon Musk's recommendations.

First, the BFR uses liquid oxygen as an oxidizer. Liquid oxygen is cryogenic component, and so, how do you think, wouldn't it evaporate during long trip from Earth to Mars? The body of spaceship is heated by sunlight and cooled by it's own radiation of heat; therefore, it's temperature during the trip between Earth and Mars is dependent of its albedo, and lays somewhere near to average temperature on surface of these planets, presumably at least not below temperature on polar regions of Mars. Liquid oxygen evaporates at this temperature.

Second, Elon Musk have no possibility to change the fuel/oxidizer pair of BFR, because he planned to synthesize the fuel/oxidizer, needed for back trip to Earth, directly on Mars. This means, it is impossible to select non-cryogenic rocket fuel pair, because much more energy is needed to synthesize that kind of fuel/oxidizer. There is not enough sunlight on Mars for photovoltaic arrays, in order to generate the energy needed to synthesize enough non-cryogenic fuel/oxydizer, in a reasonable period of time.

This means, all that Martian project of SpaceX appears to be not more than unrealistic adverticement.

Also, it is interesting to me, whether SpaceX re-invented by its own the refueling of reusable spaceships, used in their Martian project, or this invention was "borrowed" from my project of three-staged spaceplane, published on the Net nearly a 5 years before, 12 Apr. 2011?
https://lychakivsky.dreamwidth.org/8214.html

In my description of such a variant of space refueling, it was clearly stated, that cryogenic fuel would evaporate during long-time space trips, and so, only non-cryogenic fuel/oxidizer pairs could be used. Again, I would say, using of all my inventions without my written permission is prohibited by all possible measures.

Last edited by Yuri Pilipishin (2018-07-14 17:27:57)

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#2 2018-07-14 19:19:56

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Some objections concerning the Elon Musk's Martian project

"There is not enough sunlight on Mars for photovoltaic arrays, in order to generate the energy needed to synthesize enough non-cryogenic fuel/oxydizer, in a reasonable period of time."

I presume you mean that we get about 43% of insolation on Mars compared with Earth.

Why do you think that prevents a PV array from generating the energy required to synthesise enough propellant/fuel? 

You can only say that if you have done a calculation and know what the power requirement is...so what do you say the power requirement will be to get one BFR spaceship back to Earth in terms of propellant/fuel production?


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#3 2018-07-14 19:48:05

kbd512
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Registered: 2015-01-02
Posts: 7,431

Re: Some objections concerning the Elon Musk's Martian project

Yuri,

The BFS (upper stage / spaceship portion of BFR) uses header tanks, or tanks within the primary propellant tanks, to hold the propellant required to land on Mars.  That is effectively a vacuum jacket design, which is how cryogens are stored here on Earth.  For soft cryogens like LOX and LCH4, that's mostly sufficient.  If SpaceX wanted a more realistic upper stage design, they would use LOX/LH2 to reduce the upper stage mass to increase the payload or structural fraction (structure being most likely) of BFS.

There's still plenty of sunlight on Mars when dust storms aren't covering the entire planet, but huge solar arrays are required to collect lots of it.  The solar powered NASA rovers use static electricity to clean the solar panels.  In a stationary array, both static electricity and gravity would be required to remove the dust loading from dust storms.  We already have lots of threads covering those topics.

ISS already uses on-orbit refueling of liquid storable chemical propellants for attitude control and periodic orbital re-boost, so you're a little late to that party.  I don't think SpaceX needs to worry about any patent infringements.

GW already explained why your 3 stage reusable space plane, as depicted on your website, won't work.  Shock impingement heating appears to get rather nasty around Mach 6 and refractory structural metal alloys turn to silly putty.  According to GW, ablatives were also tried and that didn't work, either.

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#4 2018-07-15 07:16:27

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,874

Re: Some objections concerning the Elon Musk's Martian project

I have trouble with trying to move from LEO a payload that is 150 mT once the second stage is refueled only to have an empty rocket on arrival to the mars surface.

This also all goes back to what we are doing with that payload and what is in it.

We also know that we are landing 2 seperate unmanned cargo ships as well with the same tonnage all of this is bringing the total to under the 450 mT of which some of the is support for crew.

I think there is a lessen to be learned in what we land needs to be itemized in a manifest for each ship that lands in the 3 ships that go. There is also the timing of the landings, distance from each other and of course if there is a ship landing failure of 1 going to stop a crewed mission from going seeing that we would be now down an unknown cargo of 150 mT.

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#5 2018-07-15 10:27:17

Oldfart1939
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Registered: 2016-11-26
Posts: 2,384

Re: Some objections concerning the Elon Musk's Martian project

I'll respond to this by saying the original proposals by Robert Zubrin and David Baker (Mars Direct) adequately covered some but not all of these objections. The Mars power requirements, Louis not withstanding, were (and still should be) centered on Nuclear reactor power for the first few missions. There is obviously a lot of ground to cover before any flight to the Red Planet actually takes place, and the unmanned missions (optimistically scheduled) for 2022 will need to address these problems.

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#6 2018-07-15 15:57:59

Yuri Pilipishin
Member
From: Lviv, Ukraine
Registered: 2017-05-21
Posts: 26
Website

Re: Some objections concerning the Elon Musk's Martian project

louis wrote:

Why do you think that prevents a PV array from generating the energy required to synthesise enough propellant/fuel?

You can only say that if you have done a calculation and know what the power requirement is...so what do you say the power requirement will be to get one BFR spaceship

back to Earth in terms of propellant/fuel production?

Concerning all the needed calculations, I probably won't do them by myself, instead reading the numbers from the old thread on this forum:

http://newmars.com/forums/viewtopic.php?id=7993

The only thing needed to change is, if we try to synthesize not cryogenic, but non-cryogenic fuel from H2O and CO2, this could lead to increasing of energy consumption approximately by one order of magnitude. This follows from the very basic considerations, as for creation of much economical cryogenic fuel, hydrogen/oxygen, we need only to dissolute existing molecules of water into hydrogen and oxygen, while for synthesizing of non-cryogenic fuel/oxidizer we need also to construct new molecules, often - by complicated chemoelectrical process with catalyst. Practically, it is trying to set up on Mars a small synthetic fuel generating facility, something like e-diesel which was adverticed few years ago. This technology is not worked out even here on Earth, let alone the dreams to move it to Mars and synthesize there all the fuel/oxidizer to return to Earth (and let not forget, to synthesize non-cryogenic oxidizer is more difficult than non-cryogenic fuel).

This means, the scheme of Mars trip proposed by Elon Musk, with generation of fuel/oxidizer needed to return to Earth by facility created on Mars surface, is too bulky, demands giant spaceships, and creates too much risk for a crew (what if it turned out to be impossible to synthesize fuel/oxidizer on Mars, let's say because this large fuel synthesizing facility failed in Mars conditions?) 

In my Martian project, those problems are solved in much elegant, efficient and universal way.
https://lychakivsky.dreamwidth.org/13658.html

We only use multiple and multistaged refueling, creating temporary reserves of fuel/oxidizer from refueled tankers, placed on basic orbits (low Earth orbit, medium Earth orbit, high Earth orbit, maybe geostationary orbit - than trip to Mars - high Martian orbit, low Martian orbit - and return back to Earth, in reverse order). Automatic tankers fly between those basic orbits, transferring fuel/oxidizer, and returning to Earth (for decreasing of time and cost, we could use some unreturnable tankers, but it's even possible to get along with all returnable modules). After all needed fuel reserves are situated on proper basic orbits, a cargo ship with crew and a Mars lander module fly by those "stairs", one by another, reaching Martian orbit, than visit Martian surface and return back to Earth; and after that, all tankers from basic orbits are returned to Earth. No facility on Martian surface needed, every module is reusable and could be returned to Earth, although using of unreturnable tankers could made all the expedition much cheaper. At that, all of these space modules are standard and could be than used for other space activity, except only one Martian lander module, which could be also returned to Earth. And all this without engaging of the dangerous nuclear power, everything done by conventional engines.

One could argue, this scheme would need thousands of launches of reusable tankers to low Earth orbit. That's right; but, my three-staged spaceplane is completely reusable thing, it is not rocket but aircraft, and there is nothing wrong with aircraft flying thousands of times, day by day. This creates an universal infrastructure for space transportation, and costs for the whole Martian expedition would be much reasonable.   

That way, you could see, why everyone knows Elon Musk's project, but not much people know about my project, which was disclosed before Elon Musk's one - just because honest comparation of those two projects is too infavorable for Elon Musk and SpaceX

Last edited by Yuri Pilipishin (2018-07-15 16:19:27)

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#7 2018-07-15 16:03:24

Yuri Pilipishin
Member
From: Lviv, Ukraine
Registered: 2017-05-21
Posts: 26
Website

Re: Some objections concerning the Elon Musk's Martian project

kbd512 wrote:

The BFS (upper stage / spaceship portion of BFR) uses header tanks, or tanks within the primary propellant tanks, to hold the propellant required to land on Mars.  That is effectively a vacuum jacket design, which is how cryogens are stored here on Earth.  For soft cryogens like LOX and LCH4, that's mostly sufficient.  If SpaceX wanted a more realistic upper stage design, they would use LOX/LH2 to reduce the upper stage mass to increase the payload or structural fraction (structure being most likely)

of BFS.

For long-time space trips, e.g. from Earth to Mars and Mars to Earth, even genuine vacuum jacket heatproof propellant tanks seems not sufficient. In every possible vacuum jacket tanks, still there are some small heat leaking, first because of thermal conductivity via construction elements linking inner tank to outer frame, and second, because of small thermal conductivity by heat radiation. On the long-time space trips, about a few months or more, this small heat leaking seems enough for evaporization of cryogenic propellant. And moreover, implementing of vacuum jacket technology for big main fuel tanks means catastrophic decrease in mass efficiency of the whole thing, probably it wouldn't even be able to reach on low Earth orbit with this vacuum jackets (have you ever seen vacuum-jacket containers for cryogenic liquids, and how much they weight even empty?)

One more way to solve the problem of evaporization of cryogenic propellant on long-time space trips, proposed by one Russian space engeneer when we discussed with him what project is better, my three-staged spaceplane or Russian MG-19 nuclear spaceplane (which, by design of its nuclear engine, only could use cryogenic hydrogen fuel), was implementing of small refrigerator, cooling the cryogenic propellant during long-time trip, and using energy from nuclear reactor or photovoltaic array. This method of solving the problem of evaporization of cryogenic propellant seems quite ugly and inefficient, but it was the only method for Russian MG-19 spaceplane enthusiast to try to employ my invention of the said multistaged spaceplane refueling, creating for their MG-19 a possibility to reach much far than low Earth orbit and even accomplish trip to Mars (of course, I specifically prohibit all my inventions to Russians, we Ukrainians wage war with them, it was only their attempt in discussion).

For conventional non-nuclear spaceships, when we are not restricted to use liquid hydrogen, it seems decisively more convenient to standartize on non-cryogenic fuel/oxidizer, which makes all the construction significantly simpler, much more reliable and mass-efficient.

Last edited by Yuri Pilipishin (2018-07-15 16:34:58)

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#8 2018-07-15 16:09:14

Yuri Pilipishin
Member
From: Lviv, Ukraine
Registered: 2017-05-21
Posts: 26
Website

Re: Some objections concerning the Elon Musk's Martian project

kbd512 wrote:

ISS already uses on-orbit refueling of liquid storable chemical propellants for attitude control and periodic orbital re-boost, so you're a little late to that party. 

I don't think SpaceX needs to worry about any patent infringements.

Of course, I know about refueling of orbital space station by cargo spaceship, it was known even in Soviet Union. But the invention I am talking about is something very different. It is a kind of space refueling, when we refuel not a space station, but a space carrier; it means, refueling is done in the same fuel tanks of orbital stage of space carrier, which were used when the orbital stage of the carrier accomplished it's final ascent to Earth orbit. And the refueling is done by the other orbital stage of space carrier, transferring the small rest of fuel/oxidizer, kept in its fuel tanks after final ascent to orbit, into fuel tanks of the said first orbital stage. After a few, presumably 10 - 15 such refuelings, we could end up with orbital stage of space carrier, completely refueled on orbit, and ready to fly further, carrying payload, or fuel for next stage of such multiple and multistaged refuelings.

Particularly, in case of completely reusable spaceships, it means that we could launch one spaceship on low Earth orbit, and constantly fly some another spaceship between Earth and this first spaceship, one time after another, every time transferring a small rest of fuel/oxidizer, staying in tanks of the another tanker spaceship after climbing to orbit, and addind this small amount of fuel/oxidizer into fuel tanks of the first spaceship - presumably, until fuel tanks of the first spaceship would become completely full. For completely reusable spaceships, this method of refueling is especially useful, because their fuel tanks, provided for final ascent to orbit, are sufficiently large, and no non-reusable parts, like external fuel tank, are needed for every flight; and therefore, characteristic velocity of completely refueled spaceship on orbit is sufficiently high, and cost of one refueling flight to orbit is very low.

Of course, for such a refuelings, it is needed to use non-cryogenic fuel/oxidizer, which would not evaporate during all the process of these multiple refuelings, which could take quite a lot of time. Also, every time we got a completely refueled spaceship on some orbit, we could use it as a tanker to transfer a rest of fuel even further, for some spaceship waiting on higher orbit, and so on. That way, constantly transferring fuel by these multiple and multistaged refuelings, we could fly our spaceships higher and higher, on next and next stages, on Moon, Mars, asteroids, an so on.

This new method of multiple and multistaged refueling was invented by me sometime near 1999, after I invented the first version of the said three-staged spaceplane. It was clear that such a system of multiple and multistaged refuelings demands to select some standard fuel/oxidizer, used for all operations in space (and preferably a standard docking device for refueling). First version was to use standard non-cryogenic fuel, UDMH/DNTO, but it was clear that some other variant could appear to be better after a thorough research. At the moment, it seems the best fuel would be some kind of "enchanced artificial kerosene" (syntin), and the best standard oxidizer would be concentrated hydrogen peroxide. It is also understood, that possibility to synthesize those standard components on Moon, Mars, asteroids, using local hydrogen, oxygen, carbon, and electric energy from photovoltaic arrays or nuclear reactor, would be also very important. This could create the whole interplanetary infrastructure, when different spaceships travel freely in space, refuel on some base points, or transfer fuel in their tanks for other spaceships.

That way, this particular variant of space refueling is very important, especially for the era of completely reusable spaceships. One could argue that similar space refueling was previously invented a long time ago, by Konstantin Tsiolkovsky. But, as far as I know, there were significant differences. First, as far as I know, Tsiolkovsky didn't mention the need of non-cryogenic fuel, recommending cryogenic hydrogen/oxygen fuel, which is most efficient but very inconvenient due to evaporation under sunlight. Second, Tsiolkovsky mentioned the straight-line space flight, when lots of spaceship (say, 1024) run in one parallel direction, burning half of their fuel, then one half of them transfer rest of fuel to other half, which continue running in this direction, again burning half of their fuel, again one half of spaceships refuel the other half, and so on, until we end up with only one spaceship, obtaining in that manner a very high velocity. On the difference, this my method of multiple and multistaged refueling took into account that we could fly not only in free space, but in our real Solar System, with all planets and moons on their orbits. That way, we could select some base orbit, for the first stage - low Earth orbit, where the first spaceship is waiting while the other one constantly fly between Earth and base orbit, accomplishing multiple refuelings of the first spaceship. After refueling is complete, the first spaceship could move to higher base orbit, and again wait until a few (presumably two) other tanker ships collect fuel on low base orbit ant then move it to the next, higher base orbit, further refuelling the first spaceship. That way, by completing multiple refueling on base orbits, and climbing on higher and higher base orbits, like on stairs, it is possible to reach Moon, Mars, asteroids, and other planets, usind not so many reusable spaceships. This is the difference in the method, as compared to the one proposed by Tsiolkovsky.

One more important difference of my invention of this variant of space refueling, as compared to Tsiolkovsky's (and maybe someone else), is that I have a realistic project of completely reusable spaceship, enabling the best implementation of this method of refueling. Nearly all of the previous completely reusable spaceships, as far as I know, were designed for using cryogenic fuel, because of its better impulse - but this is a proof, that their inventors never took into account possibility of such a refueling, being quite agree that their reusable spaceships could fly not higher than low Earth orbit. And even these few completely reusable spaceships which used non-cryogenic fuel, which I could find on the Net, were barely able to reach orbit, and there were no slightest mention about possibility of space refuelings, either. Therefore, the whole concept of this possibility, to refuel completely reusable spaceship into the same fuel tanks that were used when climbing into orbit, seemed to be completely unknown to other inventors of spacesheps, at the time when I disclosed this my invention of multiple and multistaged refuelings on the Net, on 12 Apr., 2011.

https://lychakivsky.dreamwidth.org/7865.html
https://lychakivsky.dreamwidth.org/8214.html

It's interesting to mention, knowing of that possibility of multiple space refuelings would be useful even in the era of non-reusable rockets. For example, if Soviet designers, for their Lunar project, used that approach of multiple refuelings by tanker rockets, staying with good-known rocket "Proton" instead of creation of the new giant rocket N-1, they could simply create one two-staged base rocket with Lunar spaceship, with second stage and spaceship reaching low Earth orbit, and 10 simple tanker rockets, for refueling that base rocket 10 times on LEO by rest of fuel/oxidizer staying in their tanks, in the same fuel/oxidizer tanks of the second stage of base rocket. After complete refueling, the second stage of base rocket, with spaceship, would be able to reach the Moon and return to Earth; in that way, Soviet Union could win the Moon race, by much cheaper cost. This is one more proof, that the concept of multiple refuelings of space carrier, made in the same fuel tanks which were used during final ascend to orbit, was not known at that time.

That is the explanation, why I am interested, whether SpaceX re-invented this multiple refuelings, used in their Martian project, by their own, or if they "borrowed" this invention from me. This invention is critical for the whole Martian project of SpaceX, without that they couldn't claim reaching and colonization of Mars. Of course, it is not pleasant to me, when my Martian project, disclosed early, is better, more elegant technically and more universal, and still unknown to most people, while Elon Musk's Martian project is proclaimed out loud for the whole world, as the highest achievement of human race or something like that. That way, I would like to ask, if they use my invention or not, because it seems, at least, unethical. First of all, this is a scientific priority, and if Elon Musk used some of my invention in his project, it should be mentioned in his officially published documents, who is the real author of the inventions - because if not, it seems like a tricky attempt of plagiarization.

And also, let's not forget about military applications of the invention. I have already mentioned my discussion with one Russian enthusiast of their MG-19 nuclear spaceplane project. After getting to know about these multiple and multistage refuelings of completely reusable spaceships, they didn't thought a lot, and simply tried to use this invention in their project, so instead of staying on low Earth orbit MG-19 become able to fly even on Mars. If we don't respect author's right to his invention, this creates possibilities of stealing it for evil regimes, first of all - for Moscow KGB. Say it to Elon Musk, if he "borrowed" the invention from me, it would be better to mention my authorship in his official documents, because if not, this creates a risk that the invention would be used for Russian military space program - the possibility which should be prevented.

Last edited by Yuri Pilipishin (2018-07-16 04:35:15)

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#9 2018-07-15 16:15:59

Yuri Pilipishin
Member
From: Lviv, Ukraine
Registered: 2017-05-21
Posts: 26
Website

Re: Some objections concerning the Elon Musk's Martian project

kbd512 wrote:

GW already explained why your 3 stage reusable space plane, as depicted on your website, won't work.  Shock impingement heating appears to get rather nasty around Mach 6 and refractory structural metal alloys turn to silly putty.  According to GW, ablatives were also tried and that didn't work, either.

Nothing at the like. My three-staged spacelane would not be affected by these shock impingement heating problems, it's only needed to explain some significant details.

In order to discuss these shock impingement heating, I read the description, and after that, everything seems simple.

http://exrocketman.blogspot.com/2017/06 … -very.html

For the flight with the first stage, the velocity of the thing is too low to be affected by these shock impingement heating. First stage works until h=25km M=2.5, and after separation of the first stage from the second/third stages, the thing runs without these two big nacelles with turbojet engines, which are adjacent from the bottom to the big delta wing, on the right and on the left sides. Probably, it was these two big nacelles, where, you decided, those shock waves would be created?

Please note, this is first stage, it is separated at comparatively low velocity, long time before these shock waves could become a problem. After separation of the first stage, the whole thing become one streamlined aerodynamical body, and no problems with shock impingement heating should appear at all. The only place where the problem could theoretically appear is, how the third stage is connected on the top of the second one. This needs rather a long description.

The top surface of the big fat wing of the second stage is nearly flat, and the bottom surface of the third stage is also nearly flat. That way, if we set the third stage on it's place on the top of the second stage, the two surfaces lays one on another, and the whole construction seems to be streamlined enough.

But, in real implementation, some intermediate separator between the top surface of the second stage and the bottom surface of the third stage would be needed. This separator should be geometrically fit to form of both second and third stage, should be constructively strong to fasten the third stage to the second one, should provide the possibility to transfer fuel/oxidizer from the second to the third stage, the possibility to properly separate the third stage from the second one, and also - it should provide the proper aerodynamical shape, in order to keep all the spaceplane optimally streamlined.

In the drawings, this separator is not shown, in order to keep drawings simple and clear. But, in real implementations, there could be different forms of such a separator. Moreover, taking into account that there could be different variants of the third stage, with different forms of bottom surface, we could implement a few different types of the separator thing, which could fit to different types of the third stage. Universal cargo ship, towing tanker, unreturnable towing tanker, and Martian lander - all these types of the third stage had different outlines of their bottom surface, and that way, needs different types of the said changeable separator thing.

From the aerodynamical point of view, different forms of these separator thing are possible. For example, it could be done in a form of a narrow pylon, connecting second and third stages, where the nose of the third stage is not forvarded by some dissector of air stream, thus forming a kind of nacelle with possibility of shock impingement heating. In this case, wing consoles of the third stage would also be not forwarded by aerodynamical cowls of the serparator thing, making all the thing more lightweight, but with danger of this shock impingement heating. But, this is only one variant of the said separator.

More aerodynamically enchanced separator could be implemented with aerodynamical element, dissecting air stream before nose of the third stage, and forming the one streamlined aerodynamic shape from bodies of the second and the third stages. Even more enchanced separator thing, could provide aerodynamical cowls which would cover not only nose of the third stage, but also a leading edges of its wings. In this case, the separator thing provides a kind of a "nest", where the leading edges of the third stage are sunk, in that way forming one streamlined aerodynamical shape with the second stage, without forming "a kind of nacelle". In this case, shock impingement heating should not be a problem, although the comparatively large aerodynamical separator thing would decrease mass efficiency.

In 1999, when I thought about all these possible implementations of aerodynamical separator between second and third stages, I didn't know about danger of shock impingement heating. However, it was clear, that connnection of the second and the third stages could create some problems of aerodynamics on high velocities. In order to properly solve these problems, it's needed to try different aerodynamical shapes of this changeable separator thing, and choosing of proper aerodynamical shape should solve the problem of shock impingement heating, too.

It is impossible to say, what other shape of some new kind of the third stage would be needed in future. For example, aerodynamical shapes of cargo and tanker are similar - but, then I invented to implement Mars lander module, which aerodynamical shape should be quite different. That way, it seems reasonable to provide a general possibility to fix on the nearly flat top surface of the second stage the said changeable separator thing, which would provide all the needed aerodynamical support for the especial shape of the selected third stage.

Last edited by Yuri Pilipishin (2018-07-15 16:37:02)

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#10 2018-07-15 17:22:51

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,874

Re: Some objections concerning the Elon Musk's Martian project

Yuri Pilipishin, By the way welcome to NewMars.

I see you have been doing alot of reading of the website and of what it will take to get to Mars and back using insitu resources.

The Space plane is much like the SLI from long ago as the shuttle was about to end.

98273main_sli-web2.jpg

http://www.spaceref.com/news/viewnews.html?id=443

01.23.02.boeing.rlv.sm.jpg

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#11 2018-07-15 18:20:01

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,431

Re: Some objections concerning the Elon Musk's Martian project

Yuri,

Re: Cryogenic Propellant Storage

* Storable chemicals represent extreme handling hazards and active thermal stabilization is still required to prevent freezing.
* We don't seem to have the technology to make anything but cryogenic propellants using the most readily available chemicals on Mars, which would be CO2 and H2O.
* As far as storage of cryogens for months at a time, some boil-off is necessary or active cooling is required.  NASA has done extensive work on limiting boil-off of cryogenic propellants.  As far as mass is concerned, the environment in orbit is a vacuum.
* The header propellant tanks store the propellant for landing on Mars and the empty main tanks used to transfer the spaceship to Mars functions as a vacuum jacket because it's in a vacuum.  On Earth, the heavy vacuum jackets you see on cryogen storage tanks are required because Earth's atmosphere is constantly trying to collapse the jacket.  There's no atmosphere in space.

Re: On-Orbit Refueling:

* Any practical orbital fuel depot will require active thermal management.  Again, NASA and ULA are actively working on this to store LOX/LH2 on orbit for use with the ACES upper stage for Vulcan.
* People thought about refueling rockets in space multiple times, at least several decades before you had the same idea.  I think you'll find that very few ideas are fundamentally new.  There's nearly always someone else who's had the same idea.  I've not seen anything in your proposal that hasn't already been thought of, tried, or operationally implemented before.

Re: Shock Impingement Heating:

* Unless the second and third stages of your vehicle, as depicted, defy basic aerodynamics, then the second and third stage airframes are still subject to shock impingement heating.  Your claim that they're not does not make it so.  It's the interface between the second and third stages.  That heating from the shock off the nose of your third stage will cut right through the second stage and it doesn't matter what it's made out of.  If the nose of the third stage was faired into the top of the second stage, then you have to figure out how to separate the two vehicles in hypersonic flight.  I've never seen or heard of that being done before on anything of the size you intended.
* Overall, your vehicle looks like Rockwell's Star Raker concept with unnecessary complexity that adds mass and reduces payload.  If you just reprised the Star Raker airframe design, then you'd get more useful payload.
* SpaceX ruled out giant winged vehicles because of the giant aerodynamic penalties associated with all other regimes of flight except gliding onto a runway here on Earth.

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#12 2018-07-16 01:51:55

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Some objections concerning the Elon Musk's Martian project

"There are many ways to skin a cat" to quote the old English proverb.

Musk's approach would not have been mine, but Musk is the only person who is anywhere close to achieving the goal with his Space X mission.

The advantages of Musk's approach include:

1.  The ability to transfer huge amounts of infrastructure and large numbers of personnel to Mars, which means they can develop ISRU very quickly.

2.  Methane compared with some other rocket fuels is relatively easy to handle (ie less dangerous).

3. Multiple rockets will be landing on Mars as part of Mission One.  This allows you to build in fail safe redundancy to the mission.

4.  The cargo BFRs land two years  in advance of the human passenger BFRs, giving added reassurance about the landing site.

Of course, there is the risk that there will be a problem with the ascent from Mars. Any first mission to Mars will carry risks. I would accept that this is perhaps a weakness of the Space X model, though, as the bigger the rocket, the more chances of an abort I would have thought, whereas a much smaller and basic ascent vehicle like the Apollo ascent vehicle is less problematic from that point of view.

I think either nuclear or a PV array can provide the power required for propellant production.

Last edited by louis (2018-07-16 04:35:54)


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#13 2018-07-17 14:48:03

Yuri Pilipishin
Member
From: Lviv, Ukraine
Registered: 2017-05-21
Posts: 26
Website

Re: Some objections concerning the Elon Musk's Martian project

kbd512 wrote:

Overall, your vehicle looks like Rockwell's Star Raker concept with unnecessary complexity that adds mass and reduces payload.  If you just reprised the Star Raker airframe design, then you'd get more useful payload.

The mentioned single-staged Rockwell's Star Raker is not able to reach orbit, at least when using the existing, or even realistically imagined on the level of our Earth science, constructive materials. It is rather a long discussion to explain, why single-staged vehicles were not able to reach orbit all the time of space era. I could explain it, but it is understandable that the explanation is not even needed. I know, and you know, that the old Star Raker project, from 1979, is not going to be implemented, that it would be not able to reach orbit if implemented, that there are much better new projects. It is understood, the only thing you are interested by saying these words, is making a false impression that your mafia managed to find some hidden method to force me to confess something quite contrary to my beliefs. Your phrase could be understood as a metaphorical proposal, that I'll get something much better, maybe lots of money, if I'll agree that the stupid Star Raker is better than my project. This methaphorical method of communication is used in business and politics in order to say something in quite understandable, but deniable manner. Of course, I know these methods very well: everyone who dare to confront against Moscow KGB knows these doublespeak methods, they often speak to you in this manner, there is nothing new in this.

Surely, you would deny this methaphoric interpretation of your words; this method of speaking is designed to be quite deniable. And sometimes, especially if some powerful hidden forces are interested, the one who write such words with second meaning, could even not see or understand this second meaning, for example being programmed by psychotronics or other mind control method (and this creates misunderstandings, leading to long-time enmities and bloodshed). In order to avoid these misunderstandings, I would say, in this discussion I deny every possible interpretation, except the straight understanding. No metaphors, no hinting, no second meaning, etc. It shold be taken into account, that Ukraine is waging war against Moscow KGB regime, and we are tired to see lots of such invectives from Moscow internet trolls; for example, some of your other words could be methaphorically interpreted in a manner that I'm afraid of Vladimir Putin. That is false, he is only despiceful KGB puppet, we call him "Khuylo" (rather a strong invective, but this KGB scoundrel deserves it). You could read my twitter,

http://twitter.com/Lychakivsky

in order to get to know about my political actions.

If someone would say to me something in private, say it in straight words, you could always send me a SMS, on my GSM phone number +380672655277.

kbd512 wrote:

Unless the second and third stages of your vehicle, as depicted, defy basic aerodynamics, then the second and third stage airframes are still subject to shock impingement heating.  Your claim that they're not does not make it so.  It's the interface between the second and third stages.  That heating from the shock off the nose of your third stage will cut right through the second stage and it doesn't matter what it's made out of.  If the nose of the third stage was faired into the top of the second stage, then you have to figure out how to separate the two vehicles in hypersonic flight.  I've never seen or heard of that being done before on anything of the size you intended.

If you thoroughly read my previous post, about the separator thing betweeen the second and the third stage, you could find the general solution, making all the problems with shock waves solved. The separator thing, fixed on the top of the second stage, could be implemented in a manner that the third stage is "sunk" into special "nest", or "pit", made to fit its outlines and hidding it's nose and leading edges from the airflow; in that way, all construction of the second and the third stages become one streamlined aerodynamical shape, without forming something like "nacelle" from the third stage. I have thought about the problem of separation of these two stages in hypersonic flight, having invented a few methods, but after thorough thinking of all the process of climbing on the orbit, this is all even not needed: the separation of the second and the third stages could be done on the height about 100 km, out of atmosphere, where the second and third stages are flown after ramjets weaken and rocket engine of the third stage is ignited, burning rocket fuel from the second stage, which is used like a big flat fuel tank. There is nothing difficult to separate the second and the third stages when they fly out of atmosphere.

kbd512 wrote:

People thought about refueling rockets in space multiple times, at least several decades before you had the same idea.  I think you'll find that very few ideas are fundamentally new.  There's nearly always someone else who's had the same idea.  I've not seen anything in your proposal that hasn't already been thought of, tried, or operationally implemented before.

Of course, I can not search all the possible prior art documents, especially taking into account that some of them could be secret; and, taking into account possible military use of the invention, forgeries are not excluded. I can say for sure, I have not seen other spaceship project with that method of multiple and multistaged refuelings, before Elon Musk disclosed his Martian project; it was disclosed some time after my Martian project, and I'm interested, if they re-invented this method or had "borrowed" it from me.

-------

And one more important thing. About a year ago, on that forum, after I described the project to win the war against KGB, by implementing my spaceplane, which could effectively broke the moral of evil Moscow regime (they couldn't stand if Ukrainians overcome them in space), we obtained a lot of important information. First of all, when reading this forum, we saw a clear message from Russian satanic cabal, most likely giving to someone a hint to fear. It was a picture of a woman, depicted in satanic entourage and dressed in clearly satanic style, and a few unlinked words in Russian language, not understandable for everyone but probably with some hints for someone. It was not linked to discussions on the forum, appeared on some random topic, and was quickly cleared by moderators. It could be understood, it was a reaction by satanic KGB cabal, ruling in Moscow, on these my texts about my three-staged spaceplane and Martian project. The satanic KGB cabal, ruling in Russian Federation, was furious, and took measures in order to prevent that my Ukrainian project wouldn't win over them.

It seems, these threats and attemps to block my project, had disclosed hidden ties of Moscow satanic KGB cabal to satanic societies in USA, so-called Illuminati. It is nearly clear, that in order to destroy Ukraine, these KGB people, often - successors of NKVD GULAG executioners, are trying to operate by hands of USA, making secret antiukrainian conspiracies with the satanic Illuminati cabal, which became hidden ruling mafia in USA in result of 9/11. This knowledge could be important for those who stand against these enemies of God.

These links between Moscow satanic KGB and satanic Illuminati are very natural, because they share the same beliefs. They hate democracy, they deny free will, they base their power on mind control practices and terror. Interestingly, in metaphor of Star Wars, they like to describe themselves as a "Dark Side", with all that bla-bla-bla about Darth Vader, centralised empires, destroying free will of common people, etc.

These beliefs of Dark Side could not win in Ukraine. All our history, Ukraine was insurgent nation, and never - imperialistic nation. And that rise of Dark Force after 9/11 in USA, explains lots of mysteries of Ukrainian politics; when satanic Moscow and satanic Illuminati destroyed Ukraine by covert operations; when stupid Poland, afflated by imperialistic dreams, rise a demand of "deheroization" of Ukrainian Insurgent Army; when international Jewry, oftenly linked to Moscow KGB, constantly try to intercept control over our state, killing Ukrainian patriots and doing business on blood, in favor of Moscow. The problem, since failure of Orange Revolution in Ukraine in 2005, was that the Dark Side (secret satanic societies) became the global ruling mafia, in result of 9/11.

The problem for USA is, if you decide to transform into Evil Empire, there are other nations in the world that would appear to be much better for that role. To become Evil Empire, for USA, means lost independence and became degraded cryptocolony of some other nation, maybe Israel, or extraterrestrial beings, of Lucifer itself. It would be good, if some people in USA obtained that knowledge, and organize some resistance. In modern USA, it's not easy, we know that.

We are on the Light Side, and my ability to type this message is an evidence, that we are still operating and have some achievements. Слава Україні.

Last edited by Yuri Pilipishin (2018-07-17 15:04:24)

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#14 2018-07-17 15:47:08

kbd512
Administrator
Registered: 2015-01-02
Posts: 7,431

Re: Some objections concerning the Elon Musk's Martian project

Yuri,

Good grief.  The history lesson and politics was interesting, but I'm not responding here to discuss politics or other topics.  I'm only interested in the engineering of your design.  I don't know anything at all about the KGB, religion or cults, etc.  I'm not speaking in metaphors, I'm being incredibly blunt and honest about the basic design concept, which could be made to work reasonably well with more refinement.

I said your concept, as originally designed, won't work well.  It's not a personal attack.  It's a statement about known aerodynamics problems.  Every aerospace design goes through a refinement process where things that are known to work well, like a reliable propulsion system, are combined with a new airframe design or new avionics, and so on.  Whenever you attempt to combine new propulsion systems, new airframes, solve new aerodynamics problems, and use new avionics to control the vehicle in flight, costs quickly spiral out of control and the project is either terminated for lack of funding or ends up costing so much as to be impractical in realistic use cases.  That's exactly what happened to the Space Shuttle.  Someone tried to make it all things to all customers and there were only a few basic use cases where it was all that useful, as a function of its astronomical cost.

So, refine your basic design concept.  Why do you need three stages?  Just design a two stage vehicle that combines your design concepts that can make orbit, deliver a useful payload for a cost comparable to existing designs, and land.  That's the most important first step in the basic design refinement process you can possibly undertake.

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#15 2018-07-17 18:48:33

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,874

Re: Some objections concerning the Elon Musk's Martian project

Please refrain from politics this folder does not allow for it...

I did find your original topic Three - staged, completely reusable spaceplane, reaching Moon & Mars.

As I was saying the Space Launch Initative was very much a reuseable space plane and its flash in the pan did not last long.

SLI is dead, what comes next?
NASA's RLV plans don't make any sense - Is it just me or...?
Space Initive Launch Vehicle
The death of SLI as we know it

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