Author Topic: NASA finally sets goals, missions for SLS - eyes multi-step plan to Mars  (Read 29678 times)

Online Coastal Ron

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I think they expect the ISS to be shut down by then, freeing a similar amount of funds (unless of course Congress cuts that off the budget entirely, something space advocates rarely consider).

Today the ISS represents our only continuous foothold in space, and the only reason to keep it going is if it is helping us to understand how humans will be able to live and work in space.  I hope we don't end the ISS before we have figured that out, since the DSG and DST are not meant to replace the functionality of the ISS - they are meant to utilize the knowledge that we have gained from the ISS to perform specific new functions.

Let's hope though that if we are still making new discoveries and still testing out new solutions for keeping humans alive in space, that we don't shut down the ISS in order to maintain a flat budget profile for NASA.  That could be shortsighted, and impact BLEO plans.

As to the DSG & DST, the funding for that has to start well before 2024, so either NASA will get a short-term bump in it's budget to cover that, or an existing program or department has to take a budget hit as their funding is shuffled away.  No good choices there...

If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline ncb1397

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I think they expect the ISS to be shut down by then, freeing a similar amount of funds (unless of course Congress cuts that off the budget entirely, something space advocates rarely consider).

As to the DSG & DST, the funding for that has to start well before 2024, so either NASA will get a short-term bump in it's budget to cover that, or an existing program or department has to take a budget hit as their funding is shuffled away.  No good choices there...

Completing commercial crew will save ~$700 million/year. Completing JWST also will save another ~200 million from the NASA topline budget. So, there is room for another $1 billion/year program very soon(within roughly 1 year). You can do DSG, DST and a planetary lander in sequence. Move to the next project when one is completed. DST can last about a decade before solar panel degradation starts to become an issue, and even then, it can probably be used for less taxing missions than Mars after that. So, the sequential approach will most likely have the lander complete before major refurbishment would take place. Regardless, you can create one or two ground spares that would be launched only after lander development is complete. Ideally, you would need $2 billion per year to do parallel development, but that would require ~5% increase to NASA's budget or, like you said, taking away from other programs like ISS. Regardless, ISS won't last forever from a safety standpoint so the point is moot long term.

Online MATTBLAK

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Make it so the solar arrays and other components are replaceable and good long-term use can be had of the thing.
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Offline oldAtlas_Eguy

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I just looked up some performance figures for an additional Vulcan ACES configuration that does not get much discussion. That is the VHA8 Vulcan Heavy ACES (with 8m faring). The vehicle could put into LEO and then with 2 Vulcan ACES prop launches delivering 75mt in total of prop these three launches combined would be able to outperform an SLS 2 on any BEO mission. 50+mt to a Lunar orbit where the ACES performs both the TLI and LOI burns. With the 8m faring would have the same volume as the SLS 2 cargo version would have.

So as I stated earlier the SLS is not a non-replaceable element in this plan. The other item here is that the max launch rate of this sized of payload delivered to ci-Lunar space is up to 6/yr. Using 2 pads the existing Atlas V for single stick Vulcan) and the existing Delta IV pad for the triple core Vulcan Heavy a combined total launches for Vulcan could be 12-24 single + 6 triple core.

From a brute force max payload weight standpoint the VHA8, FHE, and the NG would have very similar LEO capability. But add distributed (on-orbit refueling) and these three vehicles combined could support a program with mission rate/yr to cis-Lunar space at 5 times that described in this plan. The VHA8 + the on-orbit refueling charge would be at a price of ~$.5B per mission delivering 50mt to cis-Lunar space. Now also replace Orion with the commercial delivery of supplies and personnel to cis-Lunar space at an average of $.2B/mission on any of the 3 vehicles VHA, FH, or NG and you could support (2 supply missions for each personnel) on a $1.8B Orion budget of 3 personnel flights and 6 supplies. This is enough to operate the cis-Lunar gateway year-round. Now add the delivery of heavy deep space mission hardware elements 3 50mt deliveries/yr and this dwarfs the current plan's level of activity for the same operational budget for manned and unmanned missions. Only an additional budget would be required for those 3 50mt payloads and the cost of the small scale supplies delivered to the gateway for manned occupation support.

Edit: the . was misplaced its .2B not 2.B
« Last Edit: 04/19/2017 07:47 PM by oldAtlas_Eguy »

Offline RocketmanUS

I just looked up some performance figures for an additional Vulcan ACES configuration that does not get much discussion. That is the VHA8 Vulcan Heavy ACES (with 8m faring). The vehicle could put into LEO and then with 2 Vulcan ACES prop launches delivering 75mt in total of prop these three launches combined would be able to outperform an SLS 2 on any BEO mission. 50+mt to a Lunar orbit where the ACES performs both the TLI and LOI burns. With the 8m faring would have the same volume as the SLS 2 cargo version would have.

So as I stated earlier the SLS is not a non-replaceable element in this plan. The other item here is that the max launch rate of this sized of payload delivered to ci-Lunar space is up to 6/yr. Using 2 pads the existing Atlas V for single stick Vulcan) and the existing Delta IV pad for the triple core Vulcan Heavy a combined total launches for Vulcan could be 12-24 single + 6 triple core.

From a brute force max payload weight standpoint the VHA8, FHE, and the NG would have very similar LEO capability. But add distributed (on-orbit refueling) and these three vehicles combined could support a program with mission rate/yr to cis-Lunar space at 5 times that described in this plan. The VHA8 + the on-orbit refueling charge would be at a price of ~$.5B per mission delivering 50mt to cis-Lunar space. Now also replace Orion with the commercial delivery of supplies and personnel to cis-Lunar space at an average of $.2B/mission on any of the 3 vehicles VHA, FH, or NG and you could support (2 supply missions for each personnel) on a $1.8B Orion budget of 3 personnel flights and 6 supplies. This is enough to operate the cis-Lunar gateway year-round. Now add the delivery of heavy deep space mission hardware elements 3 50mt deliveries/yr and this dwarfs the current plan's level of activity for the same operational budget for manned and unmanned missions. Only an additional budget would be required for those 3 50mt payloads and the cost of the small scale supplies delivered to the gateway for manned occupation support.

Edit: the . was misplaced its .2B not 2.B
This could support Mars, moon , and gateway station, along with other BLEO missions.
Another reason I would support having Vulcan/ACES funded over SLS.

Having payloads sized for the commercial launchers means having the other launchers as backups for launch if needed.

The gateway station is not a bad idea, it just is not needed for Lunar return or first Mars missions.
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Offline Brovane

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I just looked up some performance figures for an additional Vulcan ACES configuration that does not get much discussion. That is the VHA8 Vulcan Heavy ACES (with 8m faring). The vehicle could put into LEO and then with 2 Vulcan ACES prop launches delivering 75mt in total of prop these three launches combined would be able to outperform an SLS 2 on any BEO mission. 50+mt to a Lunar orbit where the ACES performs both the TLI and LOI burns. With the 8m faring would have the same volume as the SLS 2 cargo version would have.

So as I stated earlier the SLS is not a non-replaceable element in this plan. The other item here is that the max launch rate of this sized of payload delivered to ci-Lunar space is up to 6/yr. Using 2 pads the existing Atlas V for single stick Vulcan) and the existing Delta IV pad for the triple core Vulcan Heavy a combined total launches for Vulcan could be 12-24 single + 6 triple core.

From a brute force max payload weight standpoint the VHA8, FHE, and the NG would have very similar LEO capability. But add distributed (on-orbit refueling) and these three vehicles combined could support a program with mission rate/yr to cis-Lunar space at 5 times that described in this plan. The VHA8 + the on-orbit refueling charge would be at a price of ~$.5B per mission delivering 50mt to cis-Lunar space. Now also replace Orion with the commercial delivery of supplies and personnel to cis-Lunar space at an average of $.2B/mission on any of the 3 vehicles VHA, FH, or NG and you could support (2 supply missions for each personnel) on a $1.8B Orion budget of 3 personnel flights and 6 supplies. This is enough to operate the cis-Lunar gateway year-round. Now add the delivery of heavy deep space mission hardware elements 3 50mt deliveries/yr and this dwarfs the current plan's level of activity for the same operational budget for manned and unmanned missions. Only an additional budget would be required for those 3 50mt payloads and the cost of the small scale supplies delivered to the gateway for manned occupation support.

Edit: the . was misplaced its .2B not 2.B
This could support Mars, moon , and gateway station, along with other BLEO missions.
Another reason I would support having Vulcan/ACES funded over SLS.

Having payloads sized for the commercial launchers means having the other launchers as backups for launch if needed.

The gateway station is not a bad idea, it just is not needed for Lunar return or first Mars missions.

By NASA not having a separate SHLV for just BLEO missions, there would be significant savings that could be had in fixed costs when compared to the SLS. 

So far the fixed costs, unique to the Vulcan Heavy I can come up,
   SLC-37B pad costs
   Production and ground Support for ACES with an 8M fairing
   Support for a tri-core 1st stage
 
The VH-ACES would share the same booster with the Vulcan and the same upper stage.  So this way the same hardware can be used for Commercial, USAF and NASA payloads.  This spreads your production and support fixed costs over wide number of launches, instead of 1 to 2 a year. 

By leveraging ACES with Propellant transfer in theory you could also break up missions between multiple providers. 

For example in the 3 launch example given.

Launch 1- Is FH delivering an OrbitalATK Propellant transfer vehicle to LEO.
Launch 2- Is NG delivering an OrbitalATK Propellant transfer vehicle to LEO.
Launch 3 - Is a VH/ACES delivering crewed Components to Orbit and the ACES refuels from Orbital ATK Tankers and then is launched BLEO.

All these launches would utilize separate pads and in theory and the launch, the timing would only be restricted by what the range could support.  This also spreads the work across multiple launch providers which I think would be good for the industry. 

I really like the idea, but it makes way to much sense for the powers that be in Congress to consider. 
"Look at that! If anybody ever said, "you'll be sitting in a spacecraft naked with a 134-pound backpack on your knees charging it", I'd have said "Aw, get serious". - John Young - Apollo-16

Offline A_M_Swallow

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{snip}
The gateway station is not a bad idea, it just is not needed for Lunar return or first Mars missions.

A reusable lunar lander needs a spacestation, unless you bring it back to Earth.

Offline Martin.cz

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{snip}
The gateway station is not a bad idea, it just is not needed for Lunar return or first Mars missions.

A reusable lunar lander needs a spacestation, unless you bring it back to Earth.

Can't you just leave it in some (preferably stable) orbit - then refuel and use it once needed again ? The reusable lander might need more robust systems for long-term independent flight, but that should still be doable in the given mass margins.

Offline A_M_Swallow

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{snip}
The gateway station is not a bad idea, it just is not needed for Lunar return or first Mars missions.

A reusable lunar lander needs a spacestation, unless you bring it back to Earth.

Can't you just leave it in some (preferably stable) orbit - then refuel and use it once needed again ? The reusable lander might need more robust systems for long-term independent flight, but that should still be doable in the given mass margins.

Moon orbits are not very stable so a significant amount of station keeping is required. A spacestation with ion thrusters can perform this for itself and a lander (and occasionally for a visiting vehicle bringing astronauts).
Refuelling is not just fuel other consumables such as food, water and air also need replacing. This gets complicated when performed unmanned. Unless the transfer vehicles are gigantic multiple docking will probably be needed.
Modern consumer cars can go for 6 months between services but Formula 1 race cars need to be serviced before each race. The first stage of launch vehicles need refurbishing before they can be reused. I therefore strongly suspect that even with robust systems lunar landers will need some refurbishing. The appropriate tools, including robotic arms, are best kept at a spacestation. The spacestation's habitat module can also act as the control room.

With planning only a few more functions will need adding to the proposed cis-lunar Deep Space Gateway to support a lander.

Online Coastal Ron

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Refuelling is not just fuel other consumables such as food, water and air also need replacing. This gets complicated when performed unmanned. Unless the transfer vehicles are gigantic multiple docking will probably be needed.

Humans are going to be present, so humans can do a little manual labor to refuel and replenish between trips.

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Modern consumer cars can go for 6 months between services...

Far more than that, but I understand the point you're trying to make.

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The first stage of launch vehicles need refurbishing before they can be reused.

If you're talking about the Falcon 9, they are refurbishing today because they are not yet using the Block 5 versions.  With the Block 5 the intent is to not do any repairs or refurbishment in between many sets of flights.

Quote
I therefore strongly suspect that even with robust systems lunar landers will need some refurbishing. The appropriate tools, including robotic arms, are best kept at a spacestation. The spacestation's habitat module can also act as the control room.

Space-only vehicles will likely have far different maintenance needs than vehicles that plunge through atmospheres to land on planets.

But everything wears out over time, so I'm thinking initially there won't be much maintenance but just replacement, and then over time maintenance will be added as the number of humans in space increases.

Quote
With planning only a few more functions will need adding to the proposed cis-lunar Deep Space Gateway to support a lander.

I'm not a rocket engineer, but the current DSG does look kind of small for supporting both visiting vehicles and being a permanent parking spot for a lunar lander and/or a DST.  No doubt it can and will evolve...
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline oldAtlas_Eguy

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For those familiar with the electronics industry the key is called "built-in-test". It would allow a team on Earth to do all the real refurbishment work which is the inspection and identification of what parts need to be fixed/replaced if any. This also requires that the station is also a parts depot/warehouse for the Lander. Failed parts can be discarded but the engineers would really like to get the parts that failed back to Earth for further analysis to determine how they could avoid the failure mode in the future. Such that as time goes by the refurbishment/parts replacement tasks go down to an almost gas and go situation. Think massive electrical redundancy and mechanical robustness. This increases weight but in the end reduces the cost $/kg transported from station to surface and back.

To give an example of where the F9 is headed. The first reused F9 booster cost half as much as a new one the next one will cost 1/10th of that booster = 1/20th the cost odf a new one. But even at that level of cost reduction $1M in parts and manpower still means about 5,000 to 10,000 manhours. A crew of 25 would take 5 to 10 weeks to do the inspection/refurbishment.

Offline A_M_Swallow

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An analogue to the wear and tear on a lunar lander is the maintenance and repair needed by the Morpheus Lander and Masten Space's Xodiac. Since these machines have only flown near the Earth they are not perfect models but they should give a good starting point.

Offline Nathan2go

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I re-arranged NASA Deep Space Transport design to be more suitable for spinning for artificial gravity, just to see how it would come out.  It seems to me that subjecting a crew to 3 years without gravity is a rather long time.  I just separated the hab from the propulsion module, and mounted them on a rigid boom with the solar arrays in between.

The simplest thing would be to just spin during the one year in Mars orbit (i.e. no thrusting and spinning at the same time).  This would work well if the crew spends that year operating remotely piloted rovers on Mars, for example digging for ice, drilling for liquid water, and deploying a multi-MegaWatt solar powered propellant plants for subsequent surface missions.  But a Phobos visit takes many weeks of additional Mars-centric thrusting.

For the design to be applicable to subsequent landing missions, spinning during the 305-400 day interplanetary transits is required.  This means that either the thrusters must be mounted on a non-spinning part of the stack (which is very inconvenient, given the need to keep the wide exhaust plume off the solar arrays and the c.g. shift as propellant is consumed and trash is dumped), the thrusters could be mounted on+-45 degree gimbles and the stack could aim 45 degrees between the sun and thrust direction (again inconvenient, and the solar array output drops 30% due to the mis-aim), or the thrusters could pulse once per rotation.

The pulsed thruster system is mechanically simplest, but requires power storage for most of the 10-20 seconds rotation period (perhaps with super-capacitors), and the thrusters must have four times the peak output power.   So the big concern is weight.  Also, the thrusters must be designed for numerous start-stop cycles.

The NASA design is evolved from cargo designs like the Asteroid Redirect Robotic  Mission, as well as cargo Mars missions (which will out-number manned flights about 3:1, assuming the crew flies out separately from their lander and surface hab), which needed to have the solar arrays on gimbles, to support continuous thrust as the vehicle spirals out of low Earth orbit (over a 1 year period).  Once the ship leaves Earth orbit, the needed thrust is always nearly 90 degrees to the sun, so array gimbles are not needed.  For (manned) missions staging at the cis-Lunar Deep Space Gateway (DSG), Earth-spiraling, thus array gimbles, are not needed.

This spinning design looks like it will have much more complicated assembly than the NASA design (which is apparently designed to self-deploy from a single SLS launch).  However, NASA has said the DSG is intended to assemble large vehicles (e.g. it includes a robotic arm), so maybe they are considering a spinning design.
« Last Edit: 04/25/2017 04:11 AM by Nathan2go »

Offline Oli

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Artificial gravity with SEP is a PITA.

I haven't found an easy solution out there. The arrangement in the picture below is a potential solution (a station not a SEP design). The panels do not rotate, the rest does. The thrusters would be in the back at a sufficient distance from the panels.

Also attached a similar arrangement for NTP.

This spinning design looks like it will have much more complicated assembly than the NASA design (which is apparently designed to self-deploy from a single SLS launch).  However, NASA has said the DSG is intended to assemble large vehicles (e.g. it includes a robotic arm), so maybe they are considering a spinning design.

By the way, I don't think you can rely on the fuel tanks being the same mass as the habitat, or how do you handle that?
« Last Edit: 04/24/2017 05:34 PM by Oli »

Online Coastal Ron

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I re-arranged NASA Deep Space Transport design to be more suitable for spinning for artificial gravity, just to see how it would come out.  It seems to me that subjecting a crew to 3 years without gravity is a rather long time.  I just separated the hab from the propulsion module, and mounted them on a rigid boom with the solar arrays in between.

The simplest thing would be to just spin during the one year in Mars orbit (i.e. no thrusting and spinning at the same time).  This would work well if the crew spends that year operating remotely piloted rovers on Mars, for example digging for ice, drilling for liquid water, and deploying a multi-MegaWatt solar powered propellant plants for subsequent surface missions.

A crew of 4 housed in that small of space for 3 years?  I know NASA proposed it, but I think it's a proposal that borders on being too extreme.

Which is why I don't see small vehicles like the DST as truly viable interplanetary vehicles.  Short trips out from Earth, sure, but longer trips would push the boundaries of human tolerances to small spaces in challenging environments.

As for spinning such a vehicle, logistics becomes a challenge because you have to have all of your supplies on the spinning vehicle unless you plan to use fuel to de-spin and re-spin the vehicle every time you want to take on supplies or leave the vehicle.  This is one of the core challenges rotation gravity solutions have, so it's not unique to this proposal - meaning we may need to stick with zero-G transportation systems for now.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline RanulfC

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For those familiar with the electronics industry the key is called "built-in-test". It would allow a team on Earth to do all the real refurbishment work which is the inspection and identification of what parts need to be fixed/replaced if any. This also requires that the station is also a parts depot/warehouse for the Lander. Failed parts can be discarded but the engineers would really like to get the parts that failed back to Earth for further analysis to determine how they could avoid the failure mode in the future. Such that as time goes by the refurbishment/parts replacement tasks go down to an almost gas and go situation. Think massive electrical redundancy and mechanical robustness. This increases weight but in the end reduces the cost $/kg transported from station to surface and back.

BITS doesn't allow remote "refurbishment" and it only generally allows inspection and identification of faulty components. You need either a "robot" or human on-site to actually 'fix' the fault and there's some perspective required to clarify this though;

In general BITS (Built-In-Test-System) will ID and isolate about 90+% of the faults and point to a general, (sub-component/board level) R2 (Remove-and-Replace) level "fix". This greatly reduces the amount of time it takes an 'on-site' (human) to troubleshoot/fix a problem but does not in and of itself alleviate the need for human maintenance and repair. in fact being honest BITS tends to generate about 50% on average of the 'faults' which is where redundancy and cross-check comes into play. But as noted that costs both in mass and in complexity, (which in and of itself can generate 'faults' and breakdowns keep in mind) as well as actual monetary costs. How much you can afford to reduce all the above also figures into the "robust-ness" of the system as exampled by several known systems of which the Shuttle is an example as well as aircraft and other transportation systems

A Shuttle flight could be grounded due to a fault in a single sensor system in BITS and while that sounds bad isn't that unusual for a system where mass, cost and complexity are balanced with a high reliability requirement. Simply put the Shuttle tended to have a three-check system where there was at least three sensors so that a failure of any one during flight could still be covered by continued comparison of the remaining two sensors. However this meant that BEFORE flight a failure of any of the three would then drop the 'reliability' of the system below the minimum level and therefore require the faulty sensor be replaced before flight. Now most Earth-bound transport systems, (including aircraft) are only dual if not single layer systems, (even military is often no more than a triple system) simply because the needed repair and troubleshooting infrastructure is close at hand at any given moment but this isn't going to be true of a space based system so the system has to have a 'deeper' redundancy in the BITS. But this gets complicated very quickly as while the addition of a single sensor/point (three to four) would seem to allow a single failure it's often not that simple as you are now down to your 'minimum' number and any additional failure will drop the system below that minimum. So the obvious choice is to add another, (four to five) layer and since you're that close why not go for fully redundant (five to six) level system and so on...

And this is before we get into the very real fact that the system itself can generate and propagate "faults" within itself and without 'someone' around to troubleshoot and/or repair THOSE faults or false faults you get additive down-line faults and failures that may or may not be 'real' in the first place.

BITS allows a faster troubleshooting and repair/replacement procedure but it's not without its own faults and quirks :)

Randy
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Offline Nathan2go

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Artificial gravity with SEP is a PITA.
Agreed.


...a potential solution (a station not a SEP design). The panels do not rotate, the rest does....

By the way, I don't think you can rely on the fuel tanks being the same mass as the habitat, or how do you handle that?
Certainly imbalance is a serious issue if part of the stack spins, and the other part doesn't, as in the drawing you've attached.  In my proposal, the whole thing spins and the solar arrays are supported from both sides on booms, so it's no problem when the tanks get lighter during the mission.  The c.g. will shift towards the hab, and with a constant rotation rate, the apparent gravity gets weaker.  Just spin faster to compensate.

A crew of 4 housed in that small of space for 3 years?  I know NASA proposed it, but I think it's a proposal that borders on being too extreme. ...

The 7.2 m diameter hab in the 2016 NASA paper should have about 16 times the volume of a Dragon capsule, or about 800 sq. ft. of floor space on two decks.  I think they'll get enough volunteers to fill the slots.

As for spinning such a vehicle, ... a challenge ... we may need to stick with zero-G transportation systems for now.
 
Well, the ISS astronauts have put a lot of personal sacrifice into showing that 6-7 months in zero G is ok; but three years is a lot more.  A better compromise might be to spin only in Mars orbit (with only one spin-up/down pair); that way, you can demonstrate the same regime that subsequent landing crews will experience (two years of zero-G, separated by 1-1.5 years with Martian gravity).

On the other hand, if someone does resurrect the (non-NASA) Inspiration Mars flyby mission (501 day round trip, non-stop), then maybe NASA will find the courage to skip the Mars orbit mission, and go straight to the surface for a 1.5 year stay, which decreases the need for artificial gravity.
« Last Edit: 04/25/2017 04:03 AM by Nathan2go »

Offline Oli

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...a potential solution (a station not a SEP design). The panels do not rotate, the rest does....

By the way, I don't think you can rely on the fuel tanks being the same mass as the habitat, or how do you handle that?
The c.g. will shift towards the hab, and with a constant rotation rate, the apparent gravity gets weaker.  Just spin faster to compensate.

The faster spin must be tolerable for the crew. Meaning the original spin must be slower and the vehicle longer. But I was thinking about something else. If the thrust is perpendicular to the panels (along the axis of rotation), the lighter side will have a longer lever, meaning the vehicle would start to "tumble" unless the thrust is reduced.

A crew of 4 housed in that small of space for 3 years?  I know NASA proposed it, but I think it's a proposal that borders on being too extreme. ...

The surface hab is not going to be bigger.
« Last Edit: 04/25/2017 12:36 PM by Oli »

Offline IW1DGG

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Hi all
I had a similar idea to the post from Oli some time ago and, after reading the post, I tried to quickly draw it using google scketch-up.
The design is based on re-using MPLMs (4.5m DIA) and Cygnus CPM modules (3m DIA) to have some kind of recurrent design.
Can something like this work? it should fit in the 10m SLS fairing but I am not sure about the "self deploying' mechanism.
Comment are welcome
Cheers
did you know that MPLMs, Node 2&3, Columbus Structure, ATV pressurised section and Cupola (50 % of the ISS) have been built in Torino?....

Offline Mark S

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Hi all
I had a similar idea to the post from Oli some time ago and, after reading the post, I tried to quickly draw it using google scketch-up.
The design is based on re-using MPLMs (4.5m DIA) and Cygnus CPM modules (3m DIA) to have some kind of recurrent design.
Can something like this work? it should fit in the 10m SLS fairing but I am not sure about the "self deploying' mechanism.
Comment are welcome
Cheers

That's very cool! The fact that you could get all that inside a 10m fairing is amazing.

I think that maybe the center section should be 8.4m diameter in order to have commonality of tooling with SLS.

The self-deployment would be tricky, but hey, JWST.

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