Mars 9 tons at a time.

[j05h]

The Delta IV Heavy can put 17,600 lbs into Trans Mars Injection. What crewed, in-situ utilization or scientific development can be accomplished at these available throw-weights?<br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[owenander]

I don't know, but don't the suits alone weigh like 200 lbs?<br />So assuming 3 crew average 175 lbs each with a suit, that is half a ton right there. <br /><br />I don't know, but good topic!

 

[scottb50]

Then it starts to become a matter of throw away and re-usability. Four or five launches to support a small mission gets pretty expensive if you need a new rocket for each of them. <div class="Discussion_UserSignature"> </div>

 

[jimfromnsf]

RLV would still be more expensive to develop until the launch rates are in the 40-60 per year

 

[nyarlathotep]

How long in particular do you need the crew to survive? With a closed loop ECLSS, you're still going to need a couple kilograms of consumables per day per crewmember. Add a very very tiny capsule, and a landing system and you might be able to send a midget (say Tom Cruise) on a one way suicide run. <br /><br />Whether the midget would be sane for their few remaining days once they land is another question.

 

[nyarlathotep]

"Four or five launches to support a small mission gets pretty expensive if you need a new rocket for each of them."<br /><br />Depends on the complexity of the rocket and the size of the run. Delta IV's are built meticulously by hand to extremely tight tolerances. A mass produced (many thousands of units) pressure fed could be a whole lot cheaper.<br /><br />And before Jim starts on aerospace cost models, car manufacturers and ship builders routinely engineer machines with precise tolerances and tens of thousands of parts for less than a hundredth the per pound cost of aerospace hardware. Even the Wehrmacht could figure out how to control costs.

 

[jimfromnsf]

They aren't "hand crafted" Just low production rates. There is a minimum labor force (fixed cost) to kept the factory open and still produce a product. Delta is operating at this level. <br /><br /><br />"A mass produced (many thousands of units) pressure fed could be a whole lot cheaper. "<br /><br />But very useless, since you can't launch that many, and the smaller payloads make the onorbit ops harder.<br /><br />"car manufacturers and ship builders routinely engineer machines with precise tolerances and tens of thousands of parts for less than a hundredth the per pound cost of aerospace hardware"<br /><br />car manufacturers and ship builders don't care about weight, fuel/energy costs are cheaper and energy density is lower. Not an applicable analogy. <br /><br /><br />Again it is production rates, they aren't cars but more like speciality trucks and earthmoving equipment, which aren't built on production lines neither. That is the proper analogy<br /><br /><br /><br /><br /><br />

 

[j05h]

Mars via Delta IV H doesn't necessarily mean one 9-ton package only, but can. It could mean flotilla of craft staged in LEO or L1, it could mean a single seat in a Soyuz-derived lander. When we talk about starting now to go to Mars, these are the tools we have. <br /><br />You could develop a 9t heatshield or tug-stage, a capsule for getting there and another for getting back. They might dock and fly together or each get flung TMI by their Delta. The thread title indicates the Delta providing the outward burn. With a transit window every 26 months, you would be saturating the Delta pads each cycle, plus whatever other vehicles you use. Pad limitations would probably limit you to 2-6 9t packages per window (two pads, 10-30 day process time). Can this support human activity? It definitely can support a robotic science plan.<br /><br />Each package would need cruise capability and a heatshield, plus terminal guidance. I'm assuming direct descent, especially for robotics and supplies.<br /><br />Possibilities include using Atlas V 401 for capsule to LEO, then burn to rendezvous with other departing hardware. A Soyuz capsule could be stripped down and changed for 2 people (or 1) and made just for the outbound trip and descent. The crew would exit the spent capsule as on Earth, but with suits pressurized and walk/ride to their hab. Separate vehicles could be used for Mars Ascent, Earth transit and possibly reentry - all in 9t packages and based on heritage hardware. <br /><br />I don't think it's a suicide run. Is it something practical and potentially profitable? <br /><br />What modules would be needed, including various exploration/science kit? Departure capsule/descender, ascender, Earth transfer, possibly a modular heatshield, cargo or resource modules, tankers, self-deploying power stations and ISRU, rovers and tractors. What else?<br /><br />J <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[scottb50]

I still think the best alternative is a TSTO with a fly back first stage. The same concept as SS-1, except closer to the scale of the Shuttle. Shuttle facilities can also be used pretty much as is and current employees would be guaranteed work for the foreseeable future.<br /><br />I see two versions, a medium launcher for smaller payloads and passengers and a heavy launcher for cargo and outsize payloads. Medium launchers use two liquid and two solid engines and heavies use four liquid and two solid engines.<br /><br />Identical Modules become either tanks, for liquid engines or housings for solid engines. Nozzles and motors attach independently in the same manner as the tank Segments.<br /><br />Having a strong outer structure, allows any use for the inner Tube. Four Segment Modules are the largest needed and I would recommend two or three Segment Modules for habitation. <br /><br />I see something closer to the X-34 or Shuttle, to carry people, except with engines, to allow a controlled descent like Shuttle and then maneuverability. Cargo, passengers and other payloads would attach to the same first stages.<br /> <div class="Discussion_UserSignature"> </div>

 

[owenander]

3 days to get to the moon<br />3 months to get to mars<br /><br />in 5-10 years the technology to make it to mars in a much shorter time spam will be available and we will have a full time lunar colony<br /><br />better to just focus on the more economically feasible objective (or just turn private enterprise loose).

 

[gunsandrockets]

<The Delta IV Heavy can put 17,600 lbs into Trans Mars Injection.><br /><br />The rule of thumb I believe is 1/5 of a rockets LEO payload mass equals the payload mass to the surface of Mars. So for a standard Delta IV heavy rocket, that would equal a Mars surface payload of about 10,000 lbs.<br /><br />The first thing to consider is very simple ways to increase that payload.<br /><br />I asked a ULA representative at the JPL open house some questions about the Delta IV. He confirmed that the Delta IV does not need redesign and is ready for the simple upgrade of adding some small solid rocket boosters to the stack. That would boost the Delta IV LEO payload up past 62,000 lbs.<br /><br />The Mars payload rule of thumb assumes a typical LOX/LH2 rocket engine for departure from LEO. If a more efficient rocket such as solar-thermal or solar-electric were used, the payload to Mars could double or even more.<br /><br />It's interesting to consider the possibilities because SpaceX intends to field a Delta IV heavy class rocket eventually, and Elon Musk has ambitions for travel to Mars. Imagine what might be possible with the Falcon 9 heavy!<br /><br />If the payloads of two launches of the Falcon 9 heavy were mated in LEO, and the departure stage uses solar-thermal-propulsion, then the payload to Mars approaches the capability of the old Saturn V rocket.

 

[jimfromnsf]

That's what you get for talking to a PR person. The D-IV IS going thru a minor redesign which includes an RS-68 upgrade. SRM's were excluded

 

[j05h]

<i>> The first thing to consider is very simple ways to increase that payload. </i><br /><br />Actually, the question was what can be done with current state-of-the-art rockets. I'm all for Delta/EELV evolution but would like to keep this to that subject. Upper stage/payload changes, such as SEP or STR would be my #1 first upgrade, especially if it could incorporated as a tug/aerobrake stage for other cargo. <br /><br />From Boeing's web page, the Delta IV H as currently flown can put 17,600 TMI - roughly what your 1/5th rule indicates. That means a certain amount for aerobraking and other EDL hardware, but not necessarily half of the 9t TMI. If a 1-launch or 2-launch architecture (with mid-course rendezous) could put usable payload on the surface, it is a start. Past that, what would be the added in-situ resources to leverage? <br /><br />The idea is (roughly, if it works) a two-launch scenario where a 9t Mars Capsule is launched at the Mars window, followed by a high-IsP tug. The tug catches up with the capsule, docks and provides additional resources for crew, mainly power. At Mars insertion the tug aerobrakes to some Mars orbit and releases the capsule which descends to surface. Various aerobraking schemes (one-pass, direct entry, multipass, etc) are possible. The crew meets with an 6-8t ERV on the surface. <br /><br />Cargo missions could be a 9t capsule with limited cruise stage that does precision, hi-G entry, or could meet with tug. <br /><br />Taking Zubrin's greatest point (put something on Mars, fast) and what is actually available, what can we do today? If you had a GIANT roll of cash, where would you start knowing that you have access to Delta, Atlas, Ariane, SeaLaunch, Soyuz and Proton, later Falcon? This is about in-space systems more than the launch vehicle. <br /><br />Can a single 9t capsule support 2-4 people and land them safely? Does it need a tug? What about final landing? The next step is to surge-launch from several pads during the 26 month window - d <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[keermalec]

Well I did a quick calculation on the Earth return Vehicle, as this is the critical part of the project.<br /><br />Assuming a 9 ton empty crew launcher on the martian surface which produces its own LOX and LCH4 fuel, it will need about 5.6 km/s only to get up to Mars orbit. There I suppose it will rendez-vous with an Earth Return Vehicle in orbit:<br /><br />Desired acceleration (Gs): 0.532 Gs<br />Desired delta-v: 5.6 km/s<br />ISP: 372 s<br />Fuel: LOX/LCH4 <br />Thrust: 1'558'259.64 N<br /> <br />Weight allocation of Lunar Lander/Lifter: <br /> <br />Fuel: 78.44% of ship mass<br />Thruster: 1.16% of ship mass<br />Structure: 10.00% of ship mass<br />Heat Shield: 0.00% of ship mass<br />Payload: 10.40% of ship mass<br /><br />Ie useful payload will be about 4.34 tons.<br /><br />The Apollo lander for example had a useful payload of 2.5 tons for 2 astronauts.<br /><br />I believ there should be four 9t launches:<br /><br />1 for the martian surface to orbit lifter<br />1 for the surface ressearch and life-support equipement<br />1 for the mars orbiting return vehicle<br />1 for the lander<br /><br />A critical issue is having only 9t for the Earth return vehicle, considering the crew will live together for several months in cramped quarters. The apollo command and service modules for example massed about 30 tons with fuel but were only intended for two 6-day journeys... <div class="Discussion_UserSignature"> <p><em>“An error does not become a mistake until you refuse to correct it.” John F. Kennedy</em></p> </div>

 

[gunsandrockets]

<That's what you get for talking to a PR person.><br /><br />And I should believe you instead? Why? <br /><br />The person I talked to at JPL seemed very cautious and freely admitted not knowing the answers to some of my questions, only answering those questions that he was confident about.<br /><br /><The D-IV IS going thru a minor redesign which includes an RS-68 upgrade. SRM's were excluded /><br /><br />Post your proof.

 

[jimfromnsf]

"1. And I should believe you instead? Why?"<br />"2.Post your proof.<br /><br />1. I am privy to such information daily and have contacts all over the industry and NASA's ELV program as well as other projects. I don't have to wait for an "open house" to go into JPL, I can go in anytime. If you want to take advantage of an insider's view, then believe me. If not, then wallow with masses in ignorance<br /><br />2. Can't post the design review package, ITAR and propriety

 

[j05h]

Thanks for the numbers, Kermalec.<br /><br />If you chose a site on a softer soil the craft could be pentrators. If it was on a glacier or possibly Elysium (which is a dirt-covered ice pack) the ISRU landers could incorporate the penetrator as part of their drilling rig. Autonomous, self-setting water mining. <br /><br />One mass-reducing option for ISRU is to store fuel as methane hydrate ice wrapped in mylar or kapton. As an autonomous fuel plant, the ISRU unit might rover to a water extractor, plug in and produce shelf-storable methane. Obviously this means another step to fueling the ERV, but it also leaves fuel stockpiling long-term on the surface.<br /><br />For exploration, yes, 4 or 5 craft makes sense especially with direct entry and Mars orbit rendezvous. For industrial and base-building purposes it is as many flights as often as possible.<br /><br />With this sort of architecture, the basic lander system can be tested out with cheap(er), storable hardware and food. Maybe it explodes, maybe you get the extra four-wheeler and 5kw kit.<br /><br />What kind of robots make sense in this scenario? Does it require/need a robot that can do pre-crew base preparation? I'm mostly thinking of dragging cargo together and aiding solar panel deployment, since any solar farm needs to be set up ASAP in almost any Mars scenario. <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[j05h]

<i>> I still think the best alternative is a TSTO with a fly back first stage...</i><br /><br />Whatever launcher you want, as long as it matches Delta IV H. The discussion is "Mars Lite" not launchers. Knowing that you are confined to flying 17,600 lb payloads trans-Mars, where do you start and what do you bring? <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[j05h]

Jim-<br /><br />How much modification would be required to Delta IV in terms of cost and end-user price (assuming they agreed to commercial Mars mission) to make D-IV H safe enough to put humans trans-Mars? We've discussed both EELVs being basically ready for LEO capsules, are there any show-stoppers for Mars?<br /><br />Do you think it is possible to explore and settle Mars in small packages? <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[scottb50]

If you limit your perception to Mars you will be well pressed to get much of anything. The idea is Mars should be simply another aspect of the same basic design. With that concept you can custom build various Spaceships in LEO more any mission.<br /><br />A Mars ship would obviously be larger but it would use the same Core Command Modules every other ship uses.<br /><br />I think, using proven Delta Engines, much lighter and cheaper propellant tanks and Shuttle derived SRB's for a first stage you could put 100,000 pound payloads to LEO with a two liquid version and a four engine launcher could launch a loaded Shuttle Orbiter.<br /><br /><br />In the early phases completed Modules would be taken up as payload. Once expended Upper Stage propellant tanks start to accumulate most launches will start bringing up modularized inserts and supplies to modify existing Modules. Once in LEO a Module stays there or further out.<br /><br />Crew an passenger Vehicles will be launched by the First Stage and use the Upper Stage to reach a LEO Station. <br />Roughly the size of the Shuttle Orbiter it would have larger wings and turbo-fan engines. A crew of 2, 20 passengers and tons or cargo room. <br /><br />I also don't see "Mars Lite" as possible except as a repeat of Apollo. Sure, we could put 3 guys on Mars and bring them back in a couple of years, but to just do that eliminates a lot of alternatives.<br /><br />Once in LEO it becomes a simple matter of mating various Modules to create any type of vehicle or structure. As an example a Lunar Mission could have a Core Module, a Passenger or Cargo Module and various other Modules depending on the transfer requirements. Engine Modules dock as needed, depending on the size of the outbound Vehicle or return requirements. <div class="Discussion_UserSignature"> </div>

 

[thereiwas]

I think the proposal is not a one-shot "Mars lite", but a continuing stream of shipments, 9-tons each, fired off as rapidly as possible when the window is favorable.

 

[j05h]

<i>> If you limit your perception to Mars you will be well pressed to get much of anything. The idea is Mars should be simply another aspect of the same basic design. With that concept you can custom build various Spaceships in LEO more any mission. </i><br /><br />I'm not limiting my perception, I'm limiting the subject. Mars via direct throw (no stop in LEO), using existing rockets. Mid-course rendezvous, "flotilla" operations, high-energy upper stages are all possible in this scenario. LEO assembly (I'm a fan) and HLVs (I question) are not what this is about. It's about kit and aerobraking and what you want at Mars to successfully build a base or commence exploration. This has nothing to do with HLVs and "Core Command Modules". <br /><br />What can you do with today's rockets and reasonably near-term payloads?<br /><br />The Mars Lite idea is to present a stable, achievable exploration or base-building system, not a one-shot. Fly early, fly often. It's not to mount a single Mars mission and call it quits, but to build on what's there and what we can put there now. Even if it starts as a robot work site or something, what works under these conditions? Stop dodging, what would you want in those 9t packages?<br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[jimfromnsf]

"How much modification would be required to Delta IV in terms of cost and end-user price (assuming they agreed to commercial Mars mission) to make D-IV H safe enough to put humans trans-Mars? We've discussed both EELVs being basically ready for LEO capsules, are there any show-stoppers for Mars? "<br /><br />If it can place humans in LEO, then there are no other changes needed for any other trajectories

 

[jimfromnsf]

"Roughly the size of the Shuttle Orbiter it would have larger wings and turbo-fan engines. A crew of 2, 20 passengers and tons or cargo room."<br /><br />Still a waste. reuse and wings are not justified. need 40 - 60 flights a year

 

[scottb50]

40-60 flights a year would be minimal. You have to remember it is using the same First Stage as other payloads.<br /><br />Because it goes up and it comes down wings come in very handy. I would prefer a controlled landing and the possibility of a missed approach or diversion. True if it was a Space Ship it would not need wings, but it is a transport.<br /><br />I see the moon and Mars as well as asteroids and even Comets accessible in a very short time. <div class="Discussion_UserSignature"> </div>