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The plus for the hydrogels is that its a pressurized system and not pumps. I am liking the upward increase of possiblepayload and I think some of that is the change in mass of the heatshield for mars versus whats needed for earth.
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For a one-way shot to Mars with Red Dragon, you can use a thinner, lighter heat shield. That may well explain the recent uptick in claimed payload masses. Maybe; PICA-X is not all that dense.
I rather doubt they are seriously considering increasing propellant tank volume, which would require a new pressure cabin of different shape. That's a whole new capsule design to prove out. Thinning the heatshield is not.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Here is the Mars Sample Return Using Commercial Capabilities
Which was to use the samples as collected by the 2020 rover to be brought back on a Red Dragon modified with a payload of a MAV,ERV and Capsule for Earth re-entry simular to StarDust as sent by 2022 onward.
MAV + ERV length 2.80 m
Maximum Diameter 1.02 m
GLOM 1,300 Kg
SpaceX's Red Dragon mission will cost around $320 million, NASA hints
SpaceX still has a few crucial goals to meet before the Red Dragon mission can happen.
First, it has to launch its Falcon Heavy, the huge heavy lift rocket that is basically three Falcon 9s strapped together. The rocket will have enough thrust to get a heavy payload like the Red Dragon to Mars, but the massive rocket has yet to fly.
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Very good New Year News! At last things are beginning to sound very real - we have moved from the theoretical processes of colonisation to being on the cusp of an actual colonisation effort! What could be more pleasing at this juncture?
$320 million is in reality small change.
I wonder whether Space X might actually begin to seek sponsorhip as well to offset some of the costs? Perhaps not but that option is there.
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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It also tells me that we could make a 1 manned mission as well which would be short stay if we can get a Mav off the ground to get back to awaiting orbital unit.
Just going to keep dumping any document that I find into the topic as it happens.
http://www.lpi.usra.edu/meetings/marsco … f/4315.pdf
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Searching still for the specifics for the Red Dragon...
http://www.space.com/24984-spacex-mars- … ragon.html
http://www.space.com/24982-red-dragon-m … mages.html
The new study demonstrates the viability of the entry, descent and landing of the unmanned Dragon space capsule at Mars. Moreover, the spacecraft's descent technique would help set the stage for future human missions to the Red Planet, researchers said.
The study group spent a couple of years reviewing the engineering problem. They concluded that a minimally modified Dragon capsule — dubbed "Red Dragon" — could indeed successfully perform an all-propulsive entry, descent and landing on Mars "without violating the laws of physics," Lemke said.
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This article is about a year later...Future In-Space Operations (FISO) working group.
http://spirit.as.utexas.edu/~fiso/archivelist.htm
http://www.space.com/30504-spacex-red-d … eturn.html
http://www.space.com/12033-spacex-drago … aphic.html
http://www.space.com/26025-spacex-falco … aphic.html
http://spirit.as.utexas.edu/%7Efiso/tel … 21-16.pptx
http://spirit.as.utexas.edu/%7Efiso/tel … 9-9-15.pdf
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Collecting manned use details for Red Dragon /Draghon VII
According to Spacex's web site Falcon-Heavy can send 13.6 metric tons to Mars. The payload sendable to the moon should be about the same number plus a tad, but far short of the 22 tons sendable to GTO. My best guess is that a Dragon v.2 maxes out fully loaded just under 13 tons, the payload to GEO of the Falcon-9 said to be capable of sending it there.
What that means, is that Falcon-Heavy/Dragon v.2 is capable of a lunar swing-by, but not entry into lunar orbit. For entry and exit into lunar orbit, you need delta-vee capability about twice the difference between lunar escape (near 2.4 km/s) and lunar orbit speed (near 1.7 km/s). So you need twice 0.7 for about 1.4 km/s sec capability.
My numbers are faked-up best guesses, but with 2 tons on board out of the rated 6, and with no trunk to act as dead inert weight, the Super Dracos have about 0.85 km/s delta-vee available. I actually was estimating Red Dragon, but the numbers are fuzzier than the differences between them. With a reduced crew and no trunk, it can enter lunar orbit, but it is stranded there. One-way trip.
Net result: lunar swing-by is possible with Falcon-Heavy/Dragon v.2, but entering lunar orbit is not unless more delta-vee (to the tune of 1.4 km/s) can be supplied separately. The Falcon second stage is restartable in space, but not configured for on-orbit refuelling, so sending up more propellants in a Falcon-9 or -Heavy wouldn't work. It would take more than a year or so to modify the stage for this refuelling and man-rate it. And a proper set of tanks to fit the payload shroud has to be designed from scratch.
You would need another small stage "ready to use" from somewhere to be sent up on a second launch. The Dragon v.2 would have to dock with it. But the acceleration under thrust would be 180-degrees out the wrong direction for the seats in the Dragon.
The only possibility might be to modify the Dragon v.2 slightly so that it could draw the added propellant directly from the extra tanks in the trunk, with a disconnection either automatic or by astronaut intervention, at the time the trunk is shed, before entry upon return. My numbers are just too fuzzy to evaluate whether a reduced crew and 2-3 tons of NTO-MMH in the trunk added to the 1.8 tons in the Dragon v.2 could get you up past the 1.4 km/s delta-vee required.
Not sure where the extra life support supplies would be stored. It's a 6 day mission, min. Dragon was not really intended for that.
But it does sound barely doable, if such a stunt is deemed desirable.
GW
http://www.space.com/17411-apollo-11-mo … aphic.html
https://en.wikipedia.org/wiki/Apollo_Lunar_Module
Apollo LM descent engines has 10,000 lbf thrust (Mass including fuel: 22,783 lb (10,334 kg)) , and 3,500 lbf thrust (Mass, gross: 10,300 lb (4,700 kg)) for ascent (the lander part is left behind).
https://en.wikipedia.org/wiki/SpaceX_rocket_engines
The Dragon's SuperDraco are intended for launch abort escape has 16,000 lbf (73,000 newtons)thrust used on a Dragon 2 capable of 6.5 t (14,000 lb) plus payload 1T.
Red Dragon concept was conceived to use a modified 3.6-meter (12 ft) diameter Dragon module and an interior volume of 7 cubic metres (250 cu ft).Burn time 25 seconds
Propellant capacity 1,388 kg (3,060 lbs)
Red Dragon 1,900 kghttp://exoscientist.blogspot.com/2012/0 … -cost.html
SpaceX has said two Falcon Heavy launches would be required to carry a manned Dragon to a lunar landing. However, the 53 metric ton payload capacity of a single Falcon Heavy would be sufficient to carry the 40 mT (Earth departure stage + lunar lander) system described below. This would require 30 mT and 10 mT gross mass Centaur-style upper stages. This page gives the cost of a ca. 20 mT Centaur upper stage as $30 million:
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I'm new to the Mars Society and this forum. In fact, this is the first forum that I've participated in. I have to say that the thought and quality of the information here is remarkable. Something you don't see on social media like Facebook. It also makes it a little intimidating to post. There's been a lot said years before I came along on this particular subject and others that are related, so please forgive me if some of this is 'old news.'
When I first heard about the Red Dragon proposal, it seems like many people were encouraged by the possibility. Also, the use of the craft did seem logical; an existing craft capable of re-entry with thrusters for landing. You can envision it getting and landing on Mars. It would even send a good statement about future human missions because it's designed to carry humans. However, after that, it kind of reminds me of the round hole-square peg problem. It seems every time I hear something new about this mission, the square peg is being hammered into the round hole. Please don't be offended, because the Dragon is a really nice square peg! It will be perfect for it's intended purpose. But, I'm seeing more hints that people are having their doubts about using this craft with all the necessary modifications. But, as I know too from personal experience, after you have been hammering on that peg for awhile, it gets more difficult to stop.
Just for example, I've heard that a rover should be deployed. But, the Dragon has a hatch designed for the egress of humans and we are not sending cp30. But, you got to have a rover; how else are you going to get the image of the Red Dragon sitting on Mars! Maybe after the hatch opens, a really long 'selfie stick' could be deployed. LOL And, if you want to have Red Dragon be part of a sample return mission, OMG
If someone was starting from the beginning and thinking about what present technologies SpaceX had that would be useful for a SRM, I would think there would be some real good ones, but not the Dragon. For example, grid fins, landing guidance to pin-point landing, deployable landing legs, reliable engines that can have multiple starts. Then, you modify something like the second stage of a Falcon 9, land, on-site production of LOX, drill core samples (no rover), have the landing craft hold the return rocket (a longer tube is a good configuration, a relatively short tear-drop shape isn't), and return the samples to an Earth orbit. No direct re-entry. Give something real good for Orion to do; collect the return samples and assure their containment.
The reason I don't think a rover should be included is that rovers are very complex, and complex goes hand & hand with expensive. Expensive to design, build, and operate. An in-place drill rig for core samples, not so complex. Lots of science for the buck.
Have on-site production of LOX for a hybrid motor for the return orbit. I believe that In-Situ production of LOX is science btw. It's a good step towards production of cryo Methane.
There are details, but I don't want for this to be a novel. I already wrote more than I intended, and hopefully, I'm not just suggesting another square peg.
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Thanks for dropping by rdierking and welcome to Newmars....
Nice first post and keep it up...as I am an arm chair rocket specialist jack of no trades.
The square peg and round capsule sure fits....as we are trying to make something that is marginally designed completely possible with a little tweaking....ok alot of tweaking....
When it costs nasa 2 billion for a flag ship mission and they launch it on a 500 million doallr rocket I think they are looking for a cheap way out.
The rover exit is simply a change to the shell with a drop door rather than a hatch.
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Thank you for being kind. It's difficult posting the first time, and if you're joining in kind of a 'devil's advocate' position it's more difficult. I had second thoughts; did I go OT, did some think I was an idiot, make them angry, etc.
Many of you are remarkably capable people with lots of knowledge in trajectories, electronics, chemistry, history, etc. I'm not an aerospace engineer, just a retired contractor and my hobby is rocketry. What I am good at comes from years of walking into a hardware store and thinking, "how can I get this done?" This approach is what is needed if you are going to do big things with less money. I know that SpaceX doesn't have a 'go to Mars aisle" for parts, although that would be a kick. I wouldn't even dismiss the Dragon parts because a good heat shield would be valuable. But, when you have to start spending time and money redesigning things like the hatch, it takes energy away from the project goal. Then, you have to think, OK, now I have the hatch open...
In my opinion, the Mars Society and SpaceX already have the big ideas. But, you need to execute big too. For SpaceX, it's go big or stay home frankly. Otherwise, just let JPL and NASA plug along for like forever. (Hopefully, you still think I'm doing OK :-)
For me, landing Red Dragon on Mars doesn't do it.
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Sounds like you are a perfect fit for these topics...able to something with nothing...and not a devil's advocate....
Nasa its self does not have much either when looking at every mission its a total start from scratch...and just uses the available launchers which can get the job done.
We agree that Red Dragon by its self does not do it but it gives baseline numbers to work within for a sample return mission to mars some time off in the future.
The curiosity rover was 1.5 mT plus sky crane and aeroshell all add up to the capability which dragon can do but its just not the right fit as is.
Of course we are speculating as the Red Dragon numbers are not all out in the open and we are using what we know from the dragon with add on of super Draco engines rather than the original Draco's with calculate fuel tank loading for a landing on Mars.
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SpaceX is very clever; incredibly open about big ideas and goals, but very secretive and tight lipped about the details. But...their accomplishments speak volumes about competency. The latest news from the mouth of Gwenn Shotwell is slightly discouraging, in that Red Dragon may not be realistic in 2018; they already have lots on their plate, ranging from a huge flight manifest backlog, to preparations for the maiden flight of Falcon Heavy this year. Ms. Shotwell stated that by deferring the next Hohmann transfer opportunity, a great payload for Red Dragon could be ready in 2020's launch window.
By the way, welcome to the Forum; I'm kinda' one of the new kids on the block myself.
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I sure would like to see the likes of the other commercial / contractor companies do some of this cutting edge projects without looking for a cost plus contract as it will in the long run benefit them to do so.
Any project is the sum of working backwards from the destination to the launch for capability to pull it off.
Much of the destination is dictated by the EDL design and the payload delivered to the surface.
The current mode of landing on mars is to use a heatshield until we pop the backshell for a parachute which then with the sky crane was to get rid of the heatshield and fire up the engines for a hoover over the landing site to lower the catrgo to the surface via a cable.
With a Red Dragon we still have a heatshield but its carried all the way to the surface. We still have a parachute to the point at which we fire up the super draco engines cutting the chutes free and landing the hole capsule and cargo on the surface.
So we do have the means to solve a fresh design based on these profiles for landing on mars.
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Perhaps the new administration will move away from Cost-Plus contracting, which only encourages cost overruns and glacial progress?
I'd really like to see the Trump Administration publish a request for bids to accomplish both the Apollo8 redux and the Apollo 9 redux, both on completion-oriented contracts.
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Abit out of the topic but it relates response.
He has in a round about way when asking for the SLS EM-1 launch to be a crewed mission of course which would lead to EM-2 as well having a crew with the newer upper stage which was to be the first manned use of the sls.
We still even at that point do not have the Apollo 11 lunar landing capability which is also just as imporatant to getting the contractors out of the rut....
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I appreciate your knowledge on this topic SpaceNut (mod). You and others know a lot more about Red Dragon and launch vehicles that me. To be honest, I lost interest in Red Dragon kind of early.
I've noticed that I've become a little anxious over the last couple of years. I would like to see some great progress in Mars exploration before I go, including a sample return mission or two. The USA had such promise in space exploration. Now, it seems like things like Red Dragon are just throwing us a bone.
It seems like NASA's goals and SpaceX goals are different for a sample return mission, but perhaps a collaboration would still be best. I suggest get there and get back with landing site subsurface collection of samples, but that's my opinion.
This is an interesting topic with lots of good information and I don't want to take it off topic. Perhaps there will be another topic about sample return missions with SpaceX technologies in the future.
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rdierking, Its not always easy learning how a new forum or how its built in features function but here is a newmars search on key words containing Red Dragon within these topics
This one is key words for Sample Return contained with these topics
You also can pick the correct forum and create a new topic to start a new discussion as you might have already seen.
Back to Nasa and Space x colaboration in getting a sample return, I believe it was JPL that ran the initial numbers for looking into using the upgraded dragon for the sample return but since this was a rogue group not authorized its kind of fallen into slow motion as there is no funding.
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Thank you; that helps to make some sense on why this idea started. I took a look at the info from 2011 on the original Red Dragon topic. The background helps. I've been following the various ideas for a SRM for about 10 years now. Mainly because of my interest in rocketry and the rocket that would be used for the sample return from the surface of Mars.
Currently, I would think that SpaceX would conclude that sending a Dragon capsule to Mars would be a bad idea. Businesses must be very careful about the inadvertent messages they send. The message could be "we can land a capsule on Mars with no hope of survival if there was a crew." You probably don't want to send humans without a significant support system, and this should go first. Also, what if the capsule crashes? That would be a serious public relations problem, and NASA would not be very happy if samples where waiting to be picked up. Usually, you send capsules that are intended for humans on test flight missions to demonstrate their safety. Like the last Orion flight test with the re-entry.
I need to gain more experience with the forum before I try to start a new topic. I noticed that some topics start with some guidelines. I originally considered making my first post to the Sample Return with In-Situ Propellant Production topic, but it listed 250 gram sample return (thought that was a bit small), and a billion dollar constraint. I hear a billion dollars thrown around so much any more it's kind of lost its meaning to me. I know it's not practical, but I have a results based value system now days.
Anyway, that's why I hope someone else that's knowledgeable would take this on.
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http://www.dailymail.co.uk/sciencetech/ … -2020.html
2018 always seemed a little ambitious...
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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It was thought that due togetting the crewed Dragon up and transporting people to the ISS was a more important position to be in.
I do not think these articles have been posted in this topic yet.
http://www.sciencemag.org/news/2016/09/ … will-it-do
Typically, NASA chooses science missions and then purchases rockets to deliver the payloads. Musk has flipped that scenario on its head, saying that he will provide a rocket and a lander, and that the rest will follow. The billionaire hasn’t said how he would pay for Red Dragon missions, although he has indicated that he would use some of his personal fortune for them.
Even without dedicated science instruments, Red Dragon could provide a wealth of scientific data to NASA. The space agency isn’t providing any funding for the mission or hiring extra people to operationally support it. But in exchange for technical support, NASA will get access to flight-test data that could help the agency increase the amount of weight it can safely carry to Mars’s surface,
https://spaceflightnow.com/2016/07/29/n … s-mission/
If SpaceX is able to dispatch a robotic Dragon capsule to land on the red planet in 2018 on time and successfully, engineers stand to get a lesson on what it will take to eventually send humans there, capturing key data on an untested Mars landing scheme a decade sooner than NASA could it, space agency officials said this week.
Billed as a high-risk, high-reward test flight, the unpiloted Red Dragon mission aims to be the first commercial spacecraft to go to another planet, and land the heaviest vehicle ever put on the surface of Mars.
“The two technologies that are needed no matter which way we go are precision landing and supersonic retro-propulsion,”
NASA’s investment over four years is estimated at about $32 million in the form of staff hours and technical analysis.
Red Dragon spacecraft will weigh between 8 and 10 tons when it lands.
Manning said SpaceX has already shared data from their Falcon 9 booster stages, which fire up their Merlin engines for a series of re-entry and landing burns. The rocket conducts those maneuvers while flying at up to 4,000 mph (6,300 kilometers per hour), depending on each launch’s specific profile.
http://www.theverge.com/2016/7/27/12297 … 20-million
SpaceX’s upcoming Red Dragon mission — the company’s plan to send one of its Dragon capsules to Mars in 2018 — is estimated to cost around $320 million, Space News reports.
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I have weight statements and delta-vee data posted over in the "interplanetary transportation" thread for Dragon, in its various incarnations.
While it might be sub-optimal for probe applications, it is a proven vehicle in one form or another. Using something that already exists takes precedence over all "theoretical" studies, no matter who does them. Data trumps theory, if you'll excuse my choice of the word "trump".
This is just the opinion of an old hand who knows the value of using what already works, or at least what is still being proven as working, with good evidence to back it up. To land on Mars you do aerobraking, which means you need a heat shield and a back-shell. Red Dragon has those features.
You also have to land after coming out of hypersonics at very low altitude, with only seconds left to impact. This is inherent at entry mass over about 1 ton at Mars. Chutes cannot help you, as JPL already knows (see Justus and Braun, their EDL paper). That leaves only retro-propulsion, which Spacex has experience with, and which NASA does not.
So what else do you need to know before deciding what path to pursue?
GW
Last edited by GW Johnson (2017-02-21 18:23:34)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Just pulling the numbers forward into the topic....
cargo and crewed Dragons
Loadout min medium heaviest units
Capsule-only dry mass 4750 4750 4750 kg
Cargo on board 1000 2000 3200 kg
Capsule-only burnout 5750 6750 7950 kg
Propellant 1890 1890 1890 kg
Capsule-only ignition 7640 8640 9840 kg
Trunk dry mass 1250 1250 1250 kg
Trunk cargo 0 0 0 kg
Total loaded trunk 8890 9890 11090 kg
Nose cap 50 50 50 kg
Total to launch 8940 9940 11140 kgCapsule-only MR 1.328696 1.280000 1.237736 none
Capsule-only delta-vee 0.934 0.811 0.701 km/srealistic capsule-only dry weight:
Crewed Dragon est. dry mass 5150 kg
-delta heat shield 50 kg “educated guess”
-life support equipment 100 kg “WAG”
-crew seats and interior fitments 100 kg “WAG”
-chutes 100 kg “WAG”
-nose cone 50 kg “educated guess”
Est. Red Dragon dry mass 4750 kg
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So chutes do precious little braking at Mars, but do they assist in controlling attitude?
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Entry angle determines attitude; the drogue chutes are principally used to decelerate the vehicle. It's conceivable the Mars Red Dragon could have larger propellant tanks than those for reentry from ISS? They currently are rated at 1900 kg capacity, and a separate tanks of both MMH and NTO. As these are NOT cryogens, weight savings obtain through NO insulation required.
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