YumonStudios
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56 minutes ago, Pipcard said:
[12] It is getting a bit excessive.
Sorry.
I can't help but do it. You're not the only one to have this problem with me.
56 minutes ago, Pipcard said:[10] That was not the final design. One of the docking ports is supposed to be used for temporary visits or crew rotations.
Ok, but isn't that what a backup docking port is for? The only reason I can see the 3rd one being needed is in case to abandon ship in an emergency, but in that case, it's definitely not ideal, but still excusable.
56 minutes ago, Pipcard said:[9] I moved the cupola so that there could be a free berthing port for a UTV at the nadir.
Ah. It's not a huge loss then, the orginal ISS design had the coupula like that too
56 minutes ago, Pipcard said:[7] They are supposed to be radiators, and that was not the final design. I wanted to combine form and function in a way that seemed somewhat plausible.
It's still kind of stupid to put it there, but I guess since you already made the station, there's not much you can do about it now. I think.
56 minutes ago, Pipcard said:[6] Downmass is a few hundred kilograms.
Well, that's better than what Mir had to work with.
56 minutes ago, Pipcard said:[5] The adapter needs to be brought up in the first place. Making the adapter wider at the top would have made it too tall for the back of the RCV.
...And you can't bring it up with the module?
Either way, the modules also lack a propulsion system in the video. How did they get up there in the first place?
56 minutes ago, Pipcard said:[5] The adapter needs to be brought up in the first place. Making the adapter wider at the top would have made it too tall for the back of the RCV.
Looking at the videos above again, that hole between the adaptor and the RCV is pretty darn skinny. Dang, I guess this station has a pretty strict waist diameter and cup size limit
(seriously though, it couldn't be designed wider? What if someone gets stuck?)
56 minutes ago, Pipcard said:[4] Stage masses (a lot of that was guesstimated based on real stage propellant fractions) and payload capacities
Thanks
And this http://www.silverbirdastronautics.com/LVperform.html
is a good tool to use for your rockets.
56 minutes ago, Pipcard said:[2] Whatever you want to do.
[3] Negishima | M-II/Negi-5 | Reusable Crew Vehicle | Space Station Mirai | M-III Launch Vehicle
Thanks.
56 minutes ago, Pipcard said:[1] I meant Epsilon seeing as Epsilon is basically a Mu-V but with the H-IIA SRB as its first stage. But in-universe, Negi-5 was introduced in the 90s, like Mu-V.
Oh. The IRL Mu-V stopped being used due to high costs, but I guess since it could be used as an ICBM, it could benefit from Mass production and make the Epsilon unnecessary...
Ok, I'll stop.
I'm actually a fan of this project, if I didn't care, I wouldn't be bothering to reply to this thread.
It's pretty impressive.
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17 hours ago, Pipcard said:
10. Not really that complex. They "look more complicated despite being more efficient to build with (a hexagon has a greater area for the length of its sides than a square, hence why bees use hexagonal honeycombs for storage)" (TVTropes link)
17 hours ago, Pipcard said:11. The trusses need to rendezvous with the station by themselves.
17 hours ago, Pipcard said:15. The plan is to use multiple launches of the 3-core M-II Heavy. And it does not need a solid upper stage when it can scale through reusability.
If my assumption that the M-II is replaced by the M-III, and the M-II is smaller than the M-III in payload, then the M-II heavy is a bad decision to use on a Moon mission. You want the biggest rocket you can make and launch in reasonable amounts (reducing complexity of the spacecraft), and a 4-core expendable supercooled M-III is a great way to make that happen.
The solid upper stage was just an idea, I knew you'd reject it anyways. It wouldn't fall under a commonly used payload class.
17 hours ago, Pipcard said:16. About 10-11 tonnes.
Thanks. But that means the M-III is OP for the RCV.
17 hours ago, Pipcard said:17. It's painted. See Vulcan with it's 'Murican decals on the LNG (liquid natural gas, mostly methane) first stage
Those were just for marketing and aesthetic purposes, like the original paint job on the SLS. Noone in their right mind would actually paint over insulation, it adds a lot of weight for not reason. The newer Vulcan images show an Orange core, which means a non-painted core:
17 hours ago, Pipcard said:12. Raptor (first stage) - 363 s Isp in vacuum (321 at sea level). Merlin (first stage) - 311 s in vacuum (282 s at sea level). Elon Musk made the compelling argument that "Using three kinds of rockets in the same vehicle may optimize its performance, but at a price: 'To a first-order approximation, you’ve just tripled your factory costs and all your operational costs'." Hydrogen/LOX is not a good common propellant for both stages for the reasons you mentioned in [4.]. Switching to an all-methane rocket will "optimize for cost" (per kg) instead of "optimizing for pure performance." Yes, there are R&D costs, but SpaceX is doing it anyway (It is good for reusability because there is less residue buildup, a.k.a. coking). The M-II was designed in the late 1980s (in-universe), decades before SpaceX disrupted the launch industry.
That's because while Merlin uses a gas-generator cycle, Raptor uses a more effcient staged combustion cycle. It's apples to oranges.
http://www.braeunig.us/space/propel.htm
This link shows the max. conventional engine (no altitude compensation or air-breathing) isp and density (minus supercooling)
RP-1 Lox: 289s ISP sea level
Ch4 Lox: 299s ISP sea level
A 10 s isp difference is not worth it. SpaceX is pursuing it because they want to eventually reuse the 2nd stage, and H2 sucks when it comes to reuse due to hydrogen embrittlement. However, it's not impossible to solve and account for, otherwise DC-X, X-33, the Space Shuttle (original, fully reusable design, before it went to sh*t), and the New Shepard all use(d) H2 propellants. And you want to reuse only for 10 flights max anyways.
Not worth it. However, though Methane can self pressurize, the F9R has shown it's not necessary to have, and helium does the job just fine.
IVF can be used if you really need infinite burns, for H2 only though. It offers a nice ~1T payload capacity boost though. I'm not saying you shoulf use it it was just a suggestion.
Also,
Quote"Using three kinds of rockets in the same vehicle may optimize its performance, but at a price: 'To a first-order approximation, you’ve just tripled your factory costs and all your operational costs'."
Implies that each stage added increases factory costs by 2x.
A 2-stage vehicle uses 2 rockets.
I'm only adding another rocket. And ULA doesn't seem to think it's a huge deal, they need to reduce prices as fast as they can to compete vs SpaceX on military launches (bribes, and relations to Lockheed and Boeing will only get you so far), and they're still cool about adding boosters to optimize payload.
H-III wants to reduce costs to go into the commerical market, but is still cool about using boosters to optimize payload. https://en.wikipedia.org/wiki/H3_Launch_Vehicle
Hell, Ariane 6 is expected to cost as much as today's F9 per kg to GTO (and possibly better than FH, depending on how well reuse goes), and it still uses boosters to optimize payload. http://spacenews.com/ariane-6-rocket-designers-say-theyll-match-or-beat-todays-spacex-prices-on-per-kilogram-basis/
Even SpaceX wanted to do it with LRBs when F5 was still a thing. http://www.spacelaunchreport.com/falcon9.html
Adding all that together, it can't cost that much more. Especially when you use the same engines and tankage diameter tooling as the core.
And in the launch scales where reuse is better than mass production, you will want to optimize payload, at least a bit.
QuoteSwitching to an all-methane rocket will "optimize for cost" (per kg) instead of "optimizing for pure performance. Yes, there are R&D costs, but SpaceX is doing it anyway (It is good for reusability because there is less residue buildup, a.k.a. coking).
It's better to lower R+D costs to build it based off H-II tech, but with modifications to the engine and processes (like Horizontal vs vertical integration) to save costs, then chase after a 10s isp increase and increase R+D costs (and thus cost per launch) (and coking isn't an enormous problem for the Merlin anyways apparently due to using an O2 rich cycle, which also is the most efficient rocket cycle.)
I guess we have different viewpoints.
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16 hours ago, Pipcard said:
The Negi-5 is the Epsilon-equivalent.
No, it isn't:
This is from the OP:
Quote16 hours ago, Pipcard said:2. At one point I was planning to make sounding rockets, but I decided to focus on things such as crew vehicles and space stations instead.
Can I do it then :3 (in KSP) ?
16 hours ago, Pipcard said:It's several threads in the "add-on development" section of the forum, not a single thread.
Can you show me to them please?
16 hours ago, Pipcard said:4. The M-II core is kerosene (RP-1) /LOX.
Can I have the stats for the M-II in general? Thanks.
16 hours ago, Pipcard said:5. See this as an example. I wanted to have a docking adapter built in (so it wouldn't need to dock to a PMA-style adapter that stuck out of a space station), but couldn't do a Dream Chaser-style adapter because the docking adapter would get in the way when jettisoning. I also wanted to save (virtual, guesstimated) mass.
? I don't see the point. Just keep it on the space station, the docking adapter can be reused then. Also, even the HL-20 attachment is wder than the one for the RCV.
16 hours ago, Pipcard said:6. No cargo version, however, there is an HTV-equivalent called the UTV (Unmanned Transfer Vehicle) "Hikyaku"
Then you probably want to make the crew vehicle carry quite a bit of downmass. How much does it have?
16 hours ago, Pipcard said:8. It's really for aesthetic reasons, I wanted the shape to be reminiscent of 未来 (Mirai). And if you look really closely, there is a station construction arm.
But those diagonal panels are pointless. They're no good as radiators, nor as solar panels (they can't move to face the Sun)
And I could only see the scientific arm for the unpressurized exposure experiments. And speaking of experiements, is this a scientific station? I would think so.
16 hours ago, Pipcard said:9. Which is why I moved it up in a later design. That was only preliminary. There was also a cupola at the bottom.
Ah, didn't notice it. Sorry. The copula looks like it is in a bad position, as it isn't on the Nadir, allowing for better Earth Observations, though.
And it's still kind of a bad position to put a docking port, even as a backup.
On 3/2/2015 at 6:40 PM, Pipcard said:Thanks.
Current WIP: the Hatsunese Space Station
Assuming the positions of the docking ports haven't changed, you can just use the 2 on the front side, which have no obstructions, and get rid of the back one. You only ever need two, (especially since this looks like a small station).
Speaking of docking ports (and assuming you use the ISS US berthing system), it would be ideal to have a 2nd docking port on the nadir. I Know one's on the bottommost module, but a good 2nd one could be located on the bottom of the left module on the back. Berthing is done from the Nadir.
Sorry for all this questioning. I hope you don't mind me criticizing your designs.
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5 minutes ago, Darnok said:
Anyone that thinks you can grow healthy food in huge city is wrong. If you think you can be healthier by running in the morning few kilometers in large city you are very wrong.But doing those things are healthier than not doing them.
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http://www.popularmechanics.com/space/a19728/kickstarter-interstellar-antimatter-engine/
QuoteI promise you, this isn't something from Coast-to-Coast AM: A former FermiLab researcher thinks he can make an antimatter engine, one that could accelerate a spaceship to 40 percent of the speed of light. And he intends to start a Kickstarter to help him build the proof of concept.
For the paltry price of $200,000, Gerald Jackson and Steven Howe (formerly of Fermilab and Los Alamos, respectively) say they can create a thrust measurement device. That device will be used to measure the thrust between a conventional thrust engine and a lightsail that would be bombarded with antimatter to push a spacecraft. They already have some pieces of their elaborate puzzle dreamed up under the banner of Hbar Technologies, LLC, but funding dried up a few years ago.
Keep in mind the $200,000 kickstarter is just for the measurement device. The entire system (minus antimatter) would apparently cost $100 Million.
And the antimatter fuel? $100 Billion per gram.
I wish them luck
. They'll need it.
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16 hours ago, Mare Veris said:
Alive astronauts or dead? You could cheat by dropping dead bodies on all the planets.
And if an alive astronaut is necessary, then when your last astronaut dies, would the land be free again?
If it would not be freed, then you could cheat by sending still-alive expendables to quickly arrive and die on the surface.
If the land would be free, then you could just kill the last astronaut of some other party, and then claim the land. This would mean that you would always have to send your colonists guarded by armies. So, nothing changes.
Why would you air-bomb dead bodies just to claim land? Just send a pressurized rover with alive humans- 3-4 missions can theoretically cover the entirety of Mars. I think that's why you need to base land claims in space on a manned base or outpost of at least 4 people, with a 100km radius around it.
And by the time land is so precious on Mars or asteroids that they'll start killing others, you'll have quite a few people in each base. You'd basically have to slaughter a small village, which could be considered an act of war.
That's probably enough to prevent that from ever happening.
16 hours ago, Spaceception said:Alive, but weapons wouldn't go with them, and would be well trained, which also brings this up: Now, I completely agree with that one, space should not have weapons, it should stay peaceful, unless aliens decide to shoot at us, but after we take care of that, it should return to a peaceful state.
Also, despite relations between the US and Russia, Astronauts and Cosmonauts get along very well together, so in the future, relations between different Astronauts from different countries would likely be relaxed rather than tense.
I think that once space gets used enough, war is inevitable, and someone will just break the treaty anyways.
15 hours ago, Steel said:But that is just a false claim to history. Why would they be the best of humanity if they are from a nation hell-bent on claiming land on another planet with the intent to exclude others?
Also historically explorers claiming new lands represent the worst of humanity, usually bringing disease and destroying cultures that have been around for years
Because people in a rival nation today are generally better off alive than dead due to globalization and free trade.
Also, there is literally nothing to bring disease to and destroy cultures of in the inner solar system, except maybe Martian bacteria.
14 hours ago, sevenperforce said:Nuclear packages are not weapons unless they are intended for offensive use. Hydrazine could be an extremely effective biological WMD but that doesn't mean using it in an engine constitutes "putting a WMD in space".
Likewise, the atmospheric test ban treaty does not prohibit peaceful use of nuclear explosives.
The test ban treaty bans weapons of mass destruction in space in general. There was to be an exception for Orion, but the Soviets didn't like it, since they feared it could be used as a loophole to send nukes in space.
And even if it was legal, you need a very good reason to build an Orion in the first place.
12 hours ago, tater said:2016 election thread
Good idea for a new KSP forums thread
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7 minutes ago, kujuman said:
One of these things is not like the other...
It's just unwise to compare F9 or NS to the STS, in practically any capacity. F9 is designed to be an economically competitive choice. STS was designed to get support from Congress. Re-using F9 stages is an opportunity to reduce costs. If it doesn't work out economically/practically, SpaceX doesn't continue the reuse avenue, and just flies expendable F9s. When the STS wasn't easy to turn around, well, what are you going to do? Tell Congress you need to design a new vehicle? Build new orbiters for each launch?
For a really quick and dirty breakdown of labor costs at SpaceX by type (manufacturing, engineering, overhead), just look at the careers page at SpaceX's site--the vast majority of positions are for manufacturing, so one should not just say, oh, SpaceX overhead isn't reduced, therefore reusability is DOA economically; okay, so what? (Yes, there are differences in wages and costs other than wages per position, and turnover probably doesn't occur at the same rate, but as a first level approximation, it ain't bad). Sure, maybe 20% of departments at SpaceX don't need to see increased labor costs w/ increased flight rate, but that 20% might have 50% of the labor.
20-30% in cost/price reduction w/ reusing first stages doesn't seem like a wildly inaccurate claim. It won't happen for several years, and the launch rate might need to reach some minimum first before it approaches that territory, but it's probably a reasonable guess. Unless we know Musk's assumptions (we don't) we can't judge very accurately the validity of the choice. Betting the company to save 20% might not make sense for established players, but betting the company for 20% if the company is a start-up has a better expected value. Reduced prices by 20% on top of 50% compared to competitors might sway customers who are on the fence already. But all of this without data is just faffing about. :-) Nibb is absolutely right: SpaceX is taking a gamble--if it pays off, others will soon follow suit, if it doesn't maybe SpaceX will vanish or be bought-out. We get to see how things go too; but until then, let's just be glad there are amazing efforts to do things a little better :-)
I already calculated the actual cost savings is 15% vs a cheap expendable rocket due to the major performance hit.
But, I got the Shuttle VS SpaceX message a long time ago, no need to keep hammering it in
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On 9/16/2015 at 5:19 PM, LordFerret said:
With the ice crust estimated to be 30 to 40 kilometers thick, we won't be visiting that ocean anytime soon. Very interesting though.
It's less thick than Europa's. We'll probably drill deep into Enceledus' crust before Europa's
On 9/16/2015 at 6:26 AM, AngelLestat said:Everybody knew about a global ocean underneath the ice. There was not enoght proof, but that explanation had a lot more possibilities to be true than just a water pocket, due how small enceladus is and knowing the source of that heat.
Nice, but I imagine that this test probe device is not RTG by the moment.
But if its mission is to take samples from the geiser, why they dont do it from the surface?
About a probe able to reach the ocean melting several km of ice, I think nuclear thermal is a best solution, they just need to find a good way to transmit info through the ice, which may not be difficult with the right wavelenght.
It's ovbiosuly not using an RTG, those cost an arm and a leg.
And samples from deep in the geyser can uncover less changed samples than those on the surface.
And good luck sending a nuclear probe to Saturn.
You'll need it.
On 9/16/2015 at 7:07 AM, LordFerret said:Thinking about it, looking at the image of the tube/tunnel created by that test probe... I wonder if they've ever looked into using the ice tunnel created by the probe as a microwave waveguide? Maybe data communication could be accomplished using microwave, beaming data back up through the tunnel. The walls of the tunnel appear smooth enough, and ice has very low bulk resistivity.
No, the probe is going to go on a curved trajectory to avoid obstacles. And the hole is likely to close over time.
On 9/16/2015 at 8:28 AM, AngelLestat said:Maybe there is some kind of wavelenght to transmit that is not absorbed by the water, and you let the submarine free of cables that can be stuck in the hole.
Gamma rays. But good luck transmitting and receiving data with those.
On 9/16/2015 at 8:38 AM, Motokid600 said:It doesn't matter if the hole gets closed off I imagine. If you can run a wire down to the ocean you can have an antenna on the end of it in the water. Then the probe swims off and communicates with that.
Problem is... What are the chances of the ice moving and severing the wire?
Doesn't water absorb radio waves? But ice tends to move. Since the global ocean was found by the ice on top moving, the wire is likely to be severed.
On 9/16/2015 at 4:07 PM, LordFerret said:Well, a smart autonomous sub could melt its way down, enter the ocean, swim around and collect data, and then melt its way back up and deliver that data. Yes? No?
No, too risky for a >$1 Billion dollar probe.
17 hours ago, Spaceception said:Revival!!
I didn't see posts about this, but what could life under the surface look like? Would be be extremely similar to possible life on Europa? Or would it be completely different?
Probably like Europa's, which would be similar to Earth's deep sea life centering around deep sea vents. Life would definitely be blind.
13 hours ago, max_creative said:There's also one on europa. I did a group project on it. Mars is ok, but has no water. It does have an atmosphere to protect from radiation. Sorta.
Europa and Enceladus have water, but also lots more radiation. Heat is partially an issue, but there's tidal heating. The radiation is the biggest problem. The soulution is to live under the ice, which block the radiation.
Any life will be under the ice, so it doesn't matter much anyways.
12 hours ago, Nuke said:do we need a cable? can we do some kind of vlf transmission. vlf would require a huge antennea, probibly in orbit, and would use a lot of power, but could penetrate ice and water. possibly even accoustic transmission. underwater acoustic communications is an established technology, used by divers, scientists, and the military. you would just need enough cable to get through the ice, and once you strike ocean, you just anchor your drill in place and deploy your rov and an acoustic transceiver. the rov would need to be semi autonomous, be able to stay in range of the transceiver (should reach pretty far), and avoid alien sharks.
Yes, the previous page has been on if we need a cable or not.
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7 minutes ago, magnemoe said:
Good point, note that an rocket who is used will be less likely to fail as its more likely to fail the first time, less the next and then less and less likely until it get old.
That's no reason to skimp on the testing.
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13 minutes ago, The Yellow Dart said:
So you are saying that inspecting the tankage, test firing, and cleaning off the rocket add up to close to the same amount of labor as manufacturing all of the in-house-made parts and assembling the whole rocket, engine and all?
Besides, they do inspections and test firings for for every new rocket already, so if this is the case (according to you), the only additional cost would be for cleaning the outside. All other costs are essentially the same as a normal launch minus the cost of the entire first stage.
They likely need to take the engines out for inspection too.
But ok, maybe I'm being a little too pessimistic.
But all the testing on a new rocket needs to be done on a reused rocket. The only employees layed off are the manufacturers, and considering a through cleaning of the inside and outside is still needed, the vast majority of the overall workforce will still be there.
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6 minutes ago, sevenperforce said:
The SSMEs couldn't be restarted in-flight. Upon landing, they were immediately removed from the orbiter and essentially rebuilt individually before being reinstalled.
In contrast, the landing of the Falcon 9 first stage already requires multiple mid-flight restarts. They have demonstrated this by successfully re-entering almost a dozen boosters so far. So just like Elon said, they can literally strap the stage down, test fire it a dozen times, and agree that it is certified for relaunch.
The F9 first stage uses nitrogen cold gas thrusters for attitude control; the Dragon uses hypergolics. Of course the Shuttle used hypergolics for both OMS and RCS.
The Merlins run very LOX-rich both to increase thrust and to prevent coking. They don't coke at all. The SSMEs ran fuel-rich because, yay diatomic hydrogen and its marvelous influence on exhaust velocity, but virtually all other fuel combinations run oxy-rich.
The repeated test-firing is intended to ensure that no damage was sustained during launch. These are engines which are test-fired repeatedly without refurbishment as part of their preflight sequence. They are designed not to sustain significant wear from normal operation (start, burn, throttling, cutoff). So we have no reason to doubt that they can simply test fire and refuel+relaunch.
They still need to thoroughly inspect it for cracks and anomalies, and clean it off, which will mean that the labor costs will decrease only minimally. The savings will be material costs.
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7 hours ago, todofwar said:
This is one of those things that still doesn't make sense to me. I understand the velocity of a gas goes up as you decrease its mass, but the rocket equation also depends on mass of fuel exhausted. If you can speed up Argon to match H2 it should give you more umph. I guess if there was a way to do that someone would have done it, but for some reason something in the back of my mind keeps saying that's not right.
You can do that. It's called an Ion drive.
Also, @KSK anything on those alternate NTR propellants?
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16 hours ago, Angeltxilon said:
This hypothesis also can explain the formation of the moon by a extremely big nuclear explosion that broken the planet (changing also the rotation axis of this and creating the required heat to obtain the liquid core), can explain the existence of natural nuclear reactors (like the nuclear reactor of Oklo), and the neutrine anomalies.
We don't need to explain the existance of natural nuclear reactors, we know those form when U-rich magma goes up to the crust.
And the formation of the moon via nuclear fission explosions sounds ridiculous. The mass of the planet above is way too much to allow for that.
16 hours ago, Angeltxilon said:There is a hypothesis that says that the earth core could contain a little subcore of several kilometers of radius, a subcore made of uranium, plutonium, thorium in constant fission and transmutation, and surrounded by a subcluster of nuclear waste of the fission and disintegration of these materials.
This hypothesis is named "georeactor model", and exposes that is possible that the energy produced from earth and others planets is not only in basis disintegration, but also by natural nuclear fission reactors.
Sounds like it would not be able to achieve fission after a few million years, as the waste would clog the reactor up and stop it from running, and the density of U-235 would become too low very quickly.
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9 minutes ago, The Yellow Dart said:
The shuttle was one of the most bloated govt. projects in history. Perhaps if the Air Force hadn't gotten involved and thrown a nightmare of unnecessary requirements at the project, they had hope of creating a sensible reusable vehicle, but that didn't happen. The Falcon9 as a launch vehicle is already designed, in production in operation and well on its way to reuse. All of the things you list will have already been accounted for by SpaceX. There could certainly be unexpected problems, but the comparative simplicity of the F9 will limit how much they can run up the costs.
Sorry, I know I'm fanboyin' it up right now, but the F9 and the Space Shuttle are not remotely the same thing.
The Shuttle would have never been made unless the USAF got involved.
And the main reason it had a crew cabin was that it was originally intended to service a giant space station, that would grow to 50 men. When it became apparent that was a fantasy, NASA changed the mission to launching satellites, but had to keep the crew cabin because so much work had already been done assuming it was there.
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4 minutes ago, tater said:
Megastructure... I remember thinking it was cool. "Machines for living," etc.
What happened?
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9 hours ago, PB666 said:
I Think they knew this would a have happened sooner or later, it was hobbling around on one leg for the last few years, so I would say its a miracle it has lasted this long.
Not to fear, hubble is still there and JWST is on its way soon.
There are numerous replacements for Kepler on the way.
NASA's is the TESS satellite, which is smaller and less capable than Kepler, but also more modern and optimized after the lessons from Kepler.
http://www.space.com/20943-alien-planet-search-new-missions.html
3 hours ago, YNM said:Hopefully they don't lost the last reaction wheel... That'd practically marks the end of the mission.
They had 2 left.
1 hour ago, PB666 said:That is probably right, iirc after two years they lost a couple. This tells us that the stabilization equipment was of not robust design. Of course its already behind its designed liftime, and basically limping for the last five years.
These telescopes need a service or replacement program, until we can get things that last 100 years (even solar panels lose about half their power in 50 years), we need tonhave a replacement program; the big one will be hubble, when that finally goes there will be a huge gap in our light telescopic capability. We have now no ability to repair or replace. By definition it would be a not like-kind replacement, unless a shuttle comparable comes about, even so no upgrade or repair capability. JWSt is great, but its really far into IR.
Imagine that the graviton hunters find evidence of two black holes merging close by, or a supernova about to blow, you want to view from all spectra, but the hubble is no longer there.
There are plenty of telescopes in all types of spectra, just not as big as Hubble. Hubble is old anyways.
Orion (plus a airlock module and unpressurized cargo module based off the Dragon, or a lunar orbital station resupply vehicle) might be able to do telesope repair, these days most big and important telescopes are in Lagrange points that can only be accessed by men via Orion/SLS. Not to mention it's probably the only way to fund a repair mission (either that, or a commercial repair vehicle based off OrbitalATK's satellite lifetime extension spacecraft http://spacenews.com/orbital-atk-believes-in-satellite-servicing-but-not-in-rocket-reusability/.) And yes, before you say JWST is not designed for servicing, I know, but the Hubble also had major replacements of components never meant to be serviced.
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http://www.silverbirdastronautics.com/LVperform.html
This LV calculator isn't working properly, every time I make a 3 stage custom rocket (or 2 stage with boosters), the results never come out...
Help please? Is anyone experiencing the same problems?
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3 minutes ago, AngelLestat said:
Elon Musk was always clear about the high cost of the first stage, It was something like a 80% to 90% from the manufacture cost of both stages
Then reuse will likely never save more than 15% in the near future.
4 minutes ago, AngelLestat said:Which also has sense for this step.. then increasing the launch rate and increasing by a lot the % of stages recoveries, they can reduce even more the cost, because operation, planning and many different cost become cheaper due experience and other factors.
The question is if launch rates will ever increase to what is needed for RLV mass production. Very unlikely, considering history has shown that the satellite market is about as inelastic as a diabetic's need for insulin.
5 minutes ago, AngelLestat said:
Is important if they can reuse the second stage, no due manufacture cost, the same for the fairings, it is due fast reusability and reduce all the test requirements than new stages take, that is when you achieve the higher cost reduction, a 747 would not be so cheap if once it reach an airport it will take 1 week to fly again.Reduce test requirements? That's a recipe for disaster- a rocket is a controlled explosion. And you still need refurbishment costs, so labor costs will not go down, at all.
7 minutes ago, AngelLestat said:Only 6.2 millons? that is something that should be dropped in your opinion? Taking into account the cost of a parachute and helicopter fuel + pilot profits?
Because if you extrapolate the 10% cost savings from the 1st stage, ou save a mere 0.62 million in launch costs. I don't think you'll recover the r+D money, but Elon is Elon, so
10 minutes ago, AngelLestat said:By the way, as @sgt_flyer said, they are made with aluminum honeycomb cover with carbon fibers.. Carbon fiber dont corrode with sea water, they are very resistant to most types of corrosion.
...and the RCS and quidance are also resistant to salt water? Either way, the aluminum will still corrode in the salt...
12 minutes ago, AngelLestat said:These fairing need a gps of course to be recovered.. so why not add two small actuators, just enough to provide a slow turn, then you set them to open at 8000m or high if is possible (with a proper slow opening), this could be enough to travel back 20 km, enough to save 40km of fuel and time for the helicopter, but the best is that you can fly both half fairings to splash in the same location. So you can recover both with 1 helicopter.
No, the fairings will come in at around the same time. You need 3 helis, one for the 1st fairing piece, one for the 2nd, and one as a backup.
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16 minutes ago, The Yellow Dart said:
All the naysayers keep saying this, that somehow the Falcon9 is going to turn into a Space Shuttle when it comes to reuse/refurbishing. How could anyone ever think that? The complexity of the space shuttle is ridiculous compared to a simple straight-forward rocket; they are simply not comparable vehicles. Furthermore, the F9 and Merlin engines were designed by SpaceX from the beginning with reuse in mind. SpaceX has shown the world many times that they can accomplish their goals, so when there is actually reason to doubt Falcon9 reuse, please let me know.
The Shuttle was also designed for reuse. That didn't stop it from being a disaster. Even the engines were very difficult to maintain.
Also, I think the F9 uses hypergolic RCS. That means more costs from draining, maintaining, and refueling the RCS system.
The Merlins also coke due to using Rp-1.
The tanks and engines undergo significant stresses in ascent, and may crack. You need to inspect for that.
There are numerous reasons why reuse may not pan out like how spaceX and its fanboys want it to.
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1 hour ago, marcushouse said:
I know there are Delta-v calculations all over this form, but I thought I'd make a video on my channel trying to break it right down and demonstrate it. I would love to know what you all think.
Running stock without plugins like Mechjeb and Kerbal Engineer can make it less simple to determine the distance your vessel can travel. These simple calculations show you how to calculate the Delta-v for your rockets stages quickly and easily with this simple formula.
Please do follow and subscribe the the channel if you like.
Why would you do it manually when you have so many delta V calculators?
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20 hours ago, RainDreamer said:
I always thought that is like, the last resort when human finally used up all available land and the only way to make more food to feed more people is to utilize the space above already used land.
The biospheric collapse would probably destroy civilization before that happened. Farms actually produce Co2.
9 hours ago, Angeltxilon said:Arcologies, layered cities, underground cities, all these are interesting concepts, but, we need really this?
I think that we will not have these types of structure until obtain very big space and transport problems, if these appear, of course.
Why? Simple because are more expensive than classical building and difficultly are applied without need.But we already have space problems, especially in East Asia.
8 hours ago, Spaceception said:Why the heck would we build something for living 9.6 km high? It'd be more like .5 kms above ground, and .5 kms below ground, with a circumference of perhaps around hundred meters.
0.5 kms below ground is a bad idea, the water table is often only a couple feet below ground.
It's probably the reason we build up instead of down.
4 hours ago, Stargate525 said:100 meter CIRCUMFERENCE? that's a building less than 100 feet on a side. That's smaller than the WTC towers were.
That's why you break it into villages. Everything you need daily has to be within that 500-1000 person bubble; transit outside that sphere needs to be rare.
Modern cities are heavily interconnected. I agree that once we get everyone into skyscrapers, having park space is essential, but they need to be close enough to make transit between blocks less than 5 minutes.
2 hours ago, YNM said:Vertical cities ??? How about people who already in the slum areas ? Like, uh India ? Or China ? They won't be able to live in one...
If you think europeans and americans already have the problem now, those two countries (continents ?) have them from long ago. Yet we don't see any vertical cities to look at... Take another high-tech example : Tokyo metropolitan area (and a few good amount of cities around it). Same as before, they actually don't have that many tall buildings area compared to the size of the whole sprawl.
How to fix the problem, you ask ? Simple : Build smaller houses. Like in the slums. Or, like in Japan.
And for those of you who think that travel will be cramped, have no worries ; as long as the time-saving worth it, people will use that to the brim. Just find some good videos on how they load the commuter train in rush hour in Japan.
Smaller houses face psychological problems. Look above for the mouse experiments, and how normal behavior broke down in crowded spaces.
If you can build bigger houses economically, and people will buy them, I see no reason not to.1 hour ago, HebaruSan said:World population is probably stabilizing (negative growth is common among first-world countries), and there's still a lot of desert that could be terraformed and settled. We probably won't get much more vertical than we already are.
Only problem is that you need a HUGE amount of water to terraform a desert. Good freaking luck getting that water.
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On 4/9/2016 at 6:57 PM, Spaceception said:
Also, would you be willing to eat lab grown meant? As long as it looks, smells, and tastes like meat?
Why naut?
On 4/9/2016 at 6:57 PM, Spaceception said:CO2 scrubbers on the building of heavily polluted areas will help take out excess CO2 out of the atmosphere, releasing the Oxygen, and using the Carbon for 3-D printing
No. Just no. That's never going to be viable, simply due to the cost of Co2 scrubbers, and high energy use (and noise). Plastics will always be cheaper from hydrocarbons.
Not to mention we have a natural Co2 scrubber that produces viable products. It's called a plant.
On 4/9/2016 at 6:57 PM, Spaceception said:3-D printing will turn junk into materials, making the use of (Most) metals obsolete as 3-D printing makes a large amount of materials almost, or as strong as metal, putting less of a strain on the amount of metal used on Earth, put simply, vertical farms, like space colonization, will greatly help reduce humanity's carbon footprint, and allow ecosystems to recover.
Yeah, not happening. I can see extensive recycling, but it's not going to replace metal mining, and it's definately not going to be able to be done from people's basements. People will probably buy 3D Printers and sell products to people who want them, as not everyone will be able to, or want those things in their houses. Also, metals need huge amounts of heat to melt, and that alone is a good reason to not have that in your house. Aluminium might be excusable though, it's lower temperature, and can be melted in a regular fireplace.
Recycling also needs large equipment to crush, flatten, sort, and melt materials. Not to mention it's an industry all by itself. The two combined kill this idea. Also, that equipment is freaking LOUD.
On 4/9/2016 at 8:57 PM, Northstar1989 said:More compact urban development would require much higher transportation costs.
Why? It should be lower, since you can walk from point A to point B instead of drive...
On 4/9/2016 at 7:13 PM, Robotengineer said:Why the heck build up? Wouldn't it be much easier to dig down, Dwarf Fortress style? (Apologies if this was addressed in one of the vids, I didn't watch them)
We have more experience building up, and it's apparently cheaper.
On 4/9/2016 at 7:21 PM, Spaceception said:True, but I'm talking about fully fledged vertical cities, not just a few here and there, but maybe the entire city being one giant building.
We need moar research!!
Isn't that the point of vertical cities?
No, that's a horrible idea. Building many smaller, but still large buildings is not only easier to build and maintain, it is also something people are a lot more used to. It's also evolutionary, which usually tends to win out, if spaceflight has taught me anything.
On 4/9/2016 at 8:10 PM, todofwar said:I remember a study someone did where they created a rat utopia, but then ramped up the pop density. As the density increased they saw more and more aberrant behavior in the rats, they started eating each other even though they had enough food and things like that. There seems to be something about dense cities that sparks increased crime and other problems, probably because our monkey brains are evolved to handle 150 social relationships at max, anything beyond this and we start seeing people as scenery or obstacles. If we ramp up density like this you're going to have to take into account the psychological stress and have quite a bit of focus on community building.
Yeah, if we have the tech to make vertical farms economical, then we should be able to build more buildings bigger and cheaper, which would mitigate this (more overall space, despite greater density per cubic meter of land). I would argue it is essential to make suburban people go to apartment buildings.
Also, giant parks and urban farms every km2 or so can mitigate this effect. So, for every km2 of city, there is .5km2 of farm or parkland. It should still be more dense than suburbs.
Also, here is a detailed account of one of those rat density studies:http://eprints.lse.ac.uk/22514/1/2308Ramadams.pdf
They apparently stopped interacting with others normally, and died out due to lack of childbirth.
The mice also stopped taking care of their children.
Scary stuff.
20 hours ago, magnemoe said:This, its an question of costs, very high buildings are prestige projects, not something you do to save money / costs. See how large my **** is basically.
Unless you like in Signapore or Japan, and land is $$$ as hell, than building up is cheaper than building out.
20 hours ago, magnemoe said:Vertical farming makes even less sense, the construction cost is the real killer here, yes its an lack of good farmland, however its far cheaper ways to make it than skyscrapers, ways who has been used in thousands of years
20 hours ago, magnemoe said:Even standard greenhouses are far cheaper. Energy cost its also an issue, if you have to supply heat and light it cost far more energy to transport the fruit a 1000 km now anything except expensive fruits make zero sense outside of a few settings like fresh salat in space or an base in Antarctica
You don't need to build skyscrapers, 4-story vertical greenhouses do well, and those are the only kinds of Vertical farms out right now. They are far cheaper, being made out of similar things used to make normal greenhouses, and also don't need a lot of lighting and a lot less extra power than you would expect.
And even a 4-story greenhouse would produce huge efficiency increases- now you can farm even in the Canadian Shield, and not only do you have extra plant space, but also controlled conditions that increase efficiency and reduce pesticide and fertilizer use.
Currently, only building costs are holding it back.
21 hours ago, kerbiloid said:Just calculate: length of your daily road to your job and back * width of the street * 100 m. Then divide it by the number of people you meet there,
You will be surprised what a small volume you indeed use.But just seeing so many people can give the feeling of overcrowdedness. Humans are intended to live in small groups, not huge cities.
22 hours ago, Darnok said:But this is nonsense, we could build like that in times when our main transport vehicle was horse, but today we have small, easy to use and fast vehicles that can transport us on large distances very fast... but we are making towns vertical and put speed limits on cars instead of go other way and build larger horizontally towns with good access for parking spots and roads.
But it makes sense, urban sprawl is a serious problem, especially since cities are often located on prime farmland, and ecologically important deltas.
On 4/9/2016 at 9:44 PM, kerbiloid said:The unavoidable robotization of industry and farming will unavoidably reduce both the cost of production and amount of people occupied in production of something.
As most of people will either be unoccupied or do unneccessary job, an average salary will be permanently decreasing.
This will suppress small companies and cause an agressive competition between the large corporations.
Also this will force all forms of unification and virtualization of the human lifespace (watch "Cloud Atlas" and the remake of "Total Recall" as an example), which will lead this competition to the battle of prices.Will it though? That's happened 3 other times in the past (the 3 other industrial revolutions) and there are usually lots of jobs after words, as new oneas re created from new tech, and increased consumption.
On 4/9/2016 at 9:44 PM, kerbiloid said:You can place millions of people more or less comfortably in a huge building several hundred meters in size - and thus you will need no city transport at all.
All you need to deliver anything from one side of such city to another: a several hundred meters high elevator (welcome to Dubai skyscrapers) and a electric carriage to move it 500 meters sideways.Ideally, yes. However, modern cities are designed so that residential, commercial, and industrial districts are all seperate, primarily to improve real estate value(no one wants to live next to a factory), and since transportation isn't that expensive. Mass transit will become essential in these giant cities, like they are today.
On 4/9/2016 at 9:22 PM, tater said:This will likely go the way of the previous megastructure movement of the 1960s.
??? What happened?
On 4/9/2016 at 9:13 PM, max_creative said:You will need:
- oxygen tanks up high
- really good structural stuff
- really fast elevators
- and lots of other stuff, like really tall cranes.
Plus, what happens when a building collapses? That would be very bad...
Which is why enormous skyscrapers are a bad idea. Build more buildings taller, not one building enormous...
On 4/9/2016 at 8:57 PM, Northstar1989 said:More compact urban development would require much higher transportation costs. Theoretically the oil supply beginning to dry up and being unable to keep pace with demand could drive this, but electric cars will ultimately allow us to just power our automobiles with coal and wind power... (preferably Wind, it's actually the cheapest power source- as coal produces a lot of pollution and CO2 that is not accounted for in its direct costs- some estimates indicate the TRUE cost of coal is as much as 3x the cost currently paid by consumers- as the ecological, health and property damage from the sulfur and nitrogen emissions, increases in lung-cancer and acid-rain from a coal power plant are not currently paid for by the consumer of the electricity...)
But it's already happening. Denser cities are more efficient, and can be serviced by mass-transit. Modern urban planning favours building up, rather than out.
On 4/9/2016 at 8:57 PM, Northstar1989 said:As for more compact farming- there are a lot of solutions to obtain more food from less land we're already not making use of. For one, genetic engineering of crops is still really just in its infancy compared to the increases in crop yields we could obtain with more aggressive adoption of the technology.
Because people hate GM crops.
On 4/9/2016 at 8:57 PM, Northstar1989 said:And finally, there's a lot to be said for growing crops underground in manmade caves, Dwarf Fortress style (just without the giant man-eating spiders), with growth-lamps, as doing this allows you to carefully control the temperature, humidity, and keep out many pests/weeds entirely (in fact, some studies have shown it's CURRENTLY economical in certain abandoned mining tunnels, with the gains in productivity making up for the costs of electricity). All of these will see more widespread use as increasing population drives increases in the the cost of food, driving farmers to increase yields in progressively more expensive ways, long before we start making serious use of vertical farming...
Energy costs are probably too high for underground farming due to needing artificial lighting. And I doubt mining tunnels have enough ventilation...
Build up in skinny 10-4 story buildings with crops and conveyors to move the crops very slowly. Then you have much lower energy costs, as you have free energy from the Sun.
On 4/9/2016 at 8:57 PM, Northstar1989 said:Further, multi-cropping (that is, planting multiple crops in the same field- such as vegetables beneath apple trees, or potatoes in the same fields as brussel sprouts...) really doesn't see enough use either, mainly as it's difficult to automate and thus requires a lot of labor.
This could change when robots become more advanced.
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11 hours ago, sevenperforce said:On 4/9/2016 at 8:51 PM, YumonStudios said:
I don't think they have any plans for developing second-stage reuse...at least, not for the Merlin engine class. I foresee them testing the Raptor engine as a BLEO Falcon 9 or Falcon Heavy upper stage, but it's anybody's guess whether they'll explore direct reuse on that stage.
They don't have plans for 2nd stage reuse yet, but it might happen if they have a higher capacity F9.
http://spaceflight101.com/spacerockets/falcon-9-ft/
And in any case, it'd apparently by a 1:1 payload penalty to reuse the 2nd stage (to LEO, GTO is probably a bit worse, but not too much, since you can aerobrake in the atmosphere if you have a solar panel or RP-1or CH4/Lox fuel cell) and since the 2nd stage is 4T dry mass, I'll say that there is a 5T to LEO penalty, allowing for margin.
That's not astronomical, and should be possible with a 5m diameter supercooled H2 Lox upper stage, or a full CH4 Lox 5m diameter supercooled F9.
11 hours ago, sevenperforce said:Red Dragon was replaced with Dragon V2. The V2 platform is supposed to be customizable enough to serve as a lander for basically any destination in the solar system.
https://en.wikipedia.org/wiki/Red_Dragon_%28spacecraft%29
It was still rejected by NASA (in the V2 version), and SpaceX would only ever use it if their Mars plans actually start to fruit (very doubtful). And in any case, the sample-return mission proposed for Dragon V2 is very doubtful in possibility- the Dragon V2 almost certainly lacks the Delta V to launch off Mars to LMO.
It would need a extra rocket stage, and at that point, you're probably better off doing the NASA flagship MSR, and get more science off it, and samples from more scientifically interesting locations.
11 hours ago, sevenperforce said:Elon seemed pretty blunt about the recert process: wash it off, do ten test fires to make sure aerodynamic stresses didn't damage anything, then refuel and refly. All from the launch site. Not much more than what Blue Origin did.
That's what the Shuttle was supposed to be like. And we all know how well that plan worked
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9 hours ago, AngelLestat said:I hear from her president that it will be a 30% discount, from 60m to 40m.
Well, F9 v1.0 was about 88% of F9 FT costs. Thus, SpaceX would actually save 18%, according to SpaceX's own words. Of course, the 30% number is likely optimistic, and SpaceX will never publiscise problems with their reusable boosters, (also, SpaceX is planning a huge number of launches, needing 4 pads, even though it seems unlikely to ever materialize) but I'm feeling generous, so I'll round that down to 15-10% overall cost savings vs a cheap expendable rocket. Fairing reuse probably won't add much to reduce the costs.
http://www.spacex.com/about/capabilities
https://en.wikipedia.org/wiki/Falcon_9_v1.0
A 10% cost reduction is nice, but not a game changer. It also probably isn't worth the effort, the R+D costs are likely to exceed the savings unless you have a lot of launches. And then you wonder why only SpaceX is bothering with reuse.
9 hours ago, AngelLestat said:In that case it has sense to recover them, you just need to attach a small parachute in each one..
20 hours ago, magnemoe said:Not sure how much they actual need outside of parachute, with parachute they should survive the splashdown too.
No, you also need a helicopter to capture them (otherwise the value of the fairing goes through the floor due to saltwater contamination) and a RCS and guidance system to keep it reentrying properly, or else it could tumble out of control. The cost of all that means at most, fairing reuse will likely only save $1- 0.5 Million. Not really noteworthy of a savings.
21 hours ago, Motokid600 said:Iirc Elon Musk said the fairing costs is in the tens of millions. And no, no shielding. They have such large surface area and low mass that they fall like feathers.
Then SpaceX is overshooting the numbers, or has some bad manufacturing processes. Ariane 5 fairings are around the same size, and apparently only cost $6.2 Million.
On 4/9/2016 at 9:10 PM, max_creative said:At least the pieces were bigger this time! Only 4 pieces! (Booster, second stage, dragon, and nosecone.)
WHOO SPACEX!!! I know Elon Musk plays ksp, but does he check the forums? I'm sure he would like the thread.
And BTW, immediately after the landing you guys literally went through 5 pages in 10 min. That's a lot of posts.
The Dragons are never reused though, and I'm fairly certain nozecones are just ejected on Dragon V1 during ascent.
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6 minutes ago, daniel l. said:
The problem i saw was that her eyes didnt move, They stayed staring in one direction the whole time, The eyes need to focus on things around her, Especially things that would catch the eye of a human, The eyes should also have a slight random twitch.
I have a feeling that if human robots become a thing, they'll be made cartoonish and obviously not human, just to bypass the uncanny valley.
I'm looking forward to my IRL MegaMan. Hey, if Capcom won't make any games for it...
HASDA - my virtual, (mostly) Japan-inspired space program (non-Kerbal)
in The Lounge
Posted
This. lol.