Author Topic: MCT Speculation and Discussion Thread 4  (Read 505613 times)

Offline JamesH

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Re: MCT Speculation and Discussion Thread 4
« Reply #1640 on: 02/11/2016 10:26 AM »
I like the way he listed space tourism as something *other* companies are doing.. and he specifically mentioned orbital space tourism in that list. I'd love to know when SpaceX decided they were too good for this market.

By too good, do you really mean not really interested in it because it's not what they want to do?

Or did you deliberately use the phrase "too bad" just to have a strawman dig at SpaceX?

Online llanitedave

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Re: MCT Speculation and Discussion Thread 4
« Reply #1641 on: 02/11/2016 02:23 PM »
I like the way he listed space tourism as something *other* companies are doing.. and he specifically mentioned orbital space tourism in that list. I'd love to know when SpaceX decided they were too good for this market.

By too good, do you really mean not really interested in it because it's not what they want to do?

Or did you deliberately use the phrase "too bad" just to have a strawman dig at SpaceX?


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Offline A_M_Swallow

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Re: MCT Speculation and Discussion Thread 4
« Reply #1642 on: 02/12/2016 08:35 AM »
I like the way he listed space tourism as something *other* companies are doing.. and he specifically mentioned orbital space tourism in that list. I'd love to know when SpaceX decided they were too good for this market.


Airlines and aircraft builders like Boeing and Airbus are different companies. The same applies to the builders and operators of ships, buses, trains and taxis. It was only a matter of time before space tourism was separated from launch vehicle construction.

Offline The Amazing Catstronaut

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Re: MCT Speculation and Discussion Thread 4
« Reply #1643 on: 02/12/2016 12:47 PM »

Airlines and aircraft builders like Boeing and Airbus are different companies. The same applies to the builders and operators of ships, buses, trains and taxis. It was only a matter of time before space tourism was separated from launch vehicle construction.

Indeed, they were separate since inception. The world's first  (sorta) hypothetical space tourist vessel (Space Ship 1), could hardly be regarded as something optimised for commercial orbital use. It was however optimised to do what it was meant to do - do multiple big ballistic arcs in a short period of time. Space Adventures are the only ones to use traditional LVs, but only to fill an opportunity left by a pre-existing service.

Blue are some of the first would-be tour providers to step away from rockets with wings (barring Space Adventures) and to head to single stage VTVL suborbital launchers for capsules, which is certainly on the same evolutionary path to commercial orbit, but again, you wouldn't use a New Shepherd to launch crew into LEO or higher.

We can safely divide at this stage commercial rocket manufacturers who make use of their own hardware between those focused on tours, and those focused on transport, with Blue the obvious hybrid.


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Offline jsgirald

Re: MCT Speculation and Discussion Thread 4
« Reply #1644 on: 02/12/2016 01:42 PM »
The 3 km/s separation seems to be the more likely scenario and the T/W ratio sounds reasonable at 0.75 so we can extrapolate different masses for the 2nd stage at separation based on an engine count and the target Raptor thrust.

7 Raptors:  16100 kN thrust,  2200 mt mass at separation.
6 Raptors:  13800 kN thrust,  1880 mt mass at separation.
5 Raptors:  11500 kN thrust, 1570 mt mass at separation.
4 Raptors:  9200 kN thrust, 1260 mt mass at separation.

I believe the 5 engine configuration is getting on the small end, my bet would be to use a hexagonal 6 engine arrangement which would provide a space for a smaller central landing engine (I dub this mini engine 'Robin').

Isn't that a bit too big? Wouldn't a 1260 mt BFS second stage, fully fueled, be enough to lift ~200 mt (50% of it being structural mass)?

And for the return trip, a 4 Raptor BFS would have a T/W > 1 in Mars anyway, even with full tanks and cargo.

I like your 'Robin' idea, I wonder if it could be a pressure fed, for safety reasons, lox/methane engine, a bit like the Superdracos but using a different propellant (Hyperdracos, anyone?). You don't need super efficient engines to reach LMO.
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Offline Burninate

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Re: MCT Speculation and Discussion Thread 4
« Reply #1645 on: 02/12/2016 03:44 PM »
The 3 km/s separation seems to be the more likely scenario and the T/W ratio sounds reasonable at 0.75 so we can extrapolate different masses for the 2nd stage at separation based on an engine count and the target Raptor thrust.

7 Raptors:  16100 kN thrust,  2200 mt mass at separation.
6 Raptors:  13800 kN thrust,  1880 mt mass at separation.
5 Raptors:  11500 kN thrust, 1570 mt mass at separation.
4 Raptors:  9200 kN thrust, 1260 mt mass at separation.

I believe the 5 engine configuration is getting on the small end, my bet would be to use a hexagonal 6 engine arrangement which would provide a space for a smaller central landing engine (I dub this mini engine 'Robin').

Isn't that a bit too big? Wouldn't a 1260 mt BFS second stage, fully fueled, be enough to lift ~200 mt (50% of it being structural mass)?

And for the return trip, a 4 Raptor BFS would have a T/W > 1 in Mars anyway, even with full tanks and cargo.

I like your 'Robin' idea, I wonder if it could be a pressure fed, for safety reasons, lox/methane engine, a bit like the Superdracos but using a different propellant (Hyperdracos, anyone?). You don't need super efficient engines to reach LMO.

Two broad groups of ideas form, with a compromise in between:

Alpha
Two stages to LEO with one RTLS (or possibly barge landing), and one upper stage to orbit
LEO, MS-ISRU refueling
Terminal stage needs ~7km/s for Mars Ascent to Earth Return, plus Earth Return Capture
May be capable of fairly fast transits if a high-efficacy aerocapture method can be found (like MAC).  Earth to Mars quickly is easier than Mars to Earth quickly.

Beta
Three stages to LEO with one RTLS, one barge landing, and one upper stage to orbit
LEO, MS-ISRU, LMO refueling
Terminal stage needs ~4.5km/s for Mars Ascent to LMO (and possibly a little more if Mars EDL is expensive)
Not capable of especially fast transits

And the compromise position, which exerts some pressure on BFR first stage to overperform (4.5km/s plus entry?  dunno), and on MCT to pack lots of thrust (+ dry mass of engines):

Gamma
Two stages to LEO with one barge landing, and one upper stage to orbit
LEO, MS-ISRU, LMO refueling
Terminal stage needs ~4.5km/s for Mars Ascent to LMO (and possibly a little more if Mars EDL is expensive)
Not capable of especially fast transits

Right now I'm leaning towards Gamma but kicking it up to 5.5km/s or 6km/s to deal with pessimistic Mars EDL while reducing pressure on BFR first stage.  The past few weeks, I've been forking on the overall mission mode though, and whether to return hab to HEO & separate a crew capsule to Earth EDL, or return the entire hab to Earth EDL.
« Last Edit: 02/12/2016 03:49 PM by Burninate »

Offline Impaler

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Re: MCT Speculation and Discussion Thread 4
« Reply #1646 on: 02/12/2016 10:21 PM »
jsgirald:
Yes with a 1260 mt mass you would be looking at around a ~200 mt burn out mass at LEO assuming that acceleration after separation is 6 km/s.  At 1880 mt separation mass the burn out mass it approaching 375 mt but that is an upper limit.  A 6 engine configuration allows for engine out (which after symmetrically shut down drops us to 4 engines).  As I expect the vehicle to be launched with cargo that requires a dry mass delivery in LEO of nearly 200 mt, thus the 4 engine configuration provides no margin for a shutdown not to mention the need to retain landing propellant when the goal is to delivery propellant to a depot.  Lastly I see the robin engine as being a sub-scale Raptor running on Methane and Lox.

Burnate:
If favor the Beta configuration but with some minor alterations. 

First I don't believe barge landing a 2nd stage is reasonable because the barge would need to be in the Indian Ocean considering the acceleration and downrange velocity the 2nd stage will achieve.  A once around the Earth orbit and landing at the launch site is more likely.

Second the terminal stage DeltaV I would target is 5.1 km/s because this would allow a launch to LMO with 25 mt of cargo and then (by my estimates) a return to mars surface with another 100 mt of cargo.  In addition with no cargo at all the DeltaV would reach 6 km/s which would be enough for a slow Hohmann transfer back to Earth.

Online Robotbeat

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Re: MCT Speculation and Discussion Thread 4
« Reply #1647 on: 02/12/2016 10:27 PM »
"Symmetrical shutdown" is not required unless you're not gimbaling your engines.
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Offline Impaler

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Re: MCT Speculation and Discussion Thread 4
« Reply #1648 on: 02/13/2016 05:42 AM »
Unlikely, most engines can only gimbal a few degrees, not enough to maintain the thrust axis through the vehicles center of mass which for a short second stage is considerably closer to the engines then it is on a long first stage.

Offline jsgirald

Re: MCT Speculation and Discussion Thread 4
« Reply #1649 on: 02/13/2016 10:43 AM »
jsgirald:
Yes with a 1260 mt mass you would be looking at around a ~200 mt burn out mass at LEO assuming that acceleration after separation is 6 km/s.  At 1880 mt separation mass the burn out mass it approaching 375 mt but that is an upper limit.  A 6 engine configuration allows for engine out (which after symmetrically shut down drops us to 4 engines).  As I expect the vehicle to be launched with cargo that requires a dry mass delivery in LEO of nearly 200 mt, thus the 4 engine configuration provides no margin for a shutdown not to mention the need to retain landing propellant when the goal is to delivery propellant to a depot.  Lastly I see the robin engine as being a sub-scale Raptor running on Methane and Lox.

Well, engine out capability is nice to have, but maybe the MCT needs to be designed simply for safe abort, i.e. if you have engine trouble you won't be going to space, but it doesn't need to end in a wreck.

Regarding tanker missions, a fully fledged, Mars capable, vehicle seems a bit of an overkill for that, probably they'll either use future iterations of Falcon, or more likely a stripped down BFR upper stage that will be their design for common 'bread and butter' missions. I'm assuming here that MCT will be a specialised upper stage for BFR.

The already famous tweet of Chris Bergin, and the last I've heard from Musk et al. make me think that BFR/MCT will represent a break from the past in terms of configuration and design, rather than simply being a bigger rocket. The reduction of the projected power of the Raptor engines also points to this. I think it won't be much heavier than an Energia/Buran stack, probably close to N1.

I suggested the secondary engine idea based on a set of beefed up Superdracos because a 'simple' pressure fed set of engines for Mars landing and take off look more reliable than a single FFSC engine.
The idea is that secondary engines get the ship airborne and then you light up the big ones for the push to orbit. As an added benefit, you don't need a launch pad equiped for big rockets. This also opens the possibility of landing the ship in a horizontal position, an idea already considered for lunar and Mars landers, which simplifies unloading, something like the Centaur derived lander proposed by Masten.

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Offline kaoru

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Re: MCT Speculation and Discussion Thread 4
« Reply #1650 on: 02/13/2016 10:47 PM »
After reading many articles/posts on Raptor, MCT, etc. and applying what I know and what I remember (which is a lot given I have an eidetic memory), I decided to throw in my .02 worth.  Basically, I put some thought as to how a Mars architecture could work.  Decidedly, I took a page out of Elon's book and went to fundamentals.  By this I mean actually functional hardware or could-be functional hardware for the task at hand.  This means reasonably sized tanks, engines, and all the subsystems necessary for a Mars mission, Earth & Mars EDL, and long term on orbit operations.  Of course, I made several assumptions which are:
* Everything is reusable; no stages, fairings, etc. jettisoned and everything has to be serviceable on surface or on orbit.
* Long term on surface or on orbit.
* Upper stage Raptor (vacuum) with CH4 Draco thrusters.  Assumed fuel depots and ISRU.  Required Integrated Vehicle Fluids (IVF) system and closed loop ECLSS.
* Efficient ascent via optimized engine nozzles and EDL via Supersonic Retro-Propulsion (SRP) using only ONE set of engines.  Engine nozzles/bells optimized for thin to no atmosphere (aka Mars thin).
* Common modules; one size fits all.  Cost efficient components in manufacturing.

Given these assumptions I dreamed up the attached image.  Of course, there is a lot more detail that I didn't include.  For example, at the top there would be an "auxiliary control" module which would contain ECLSS components and spacecraft control (aka pilot seats).  The pilot seat(s) is needed since on orbit operations could be complicated.  Like the engine bay, this module would also have a CBM ring with connection ports for fuel/electrical & ECLSS supply.  This "upper stage" is actually a spacecraft but with the benefit of have different payloads attached to the top of it (for launch; fuel, cargo, passenger modules) or can switch around on orbit, aka attach to a BA-330, the ISS, or the fuel depot.

BTW: I didn't add any technical details but the model is sized according to my best guess (via calculations) an upper stage.  4 x Raptor 4400kN@380s (vacuum); 1:3.8 CH4 to LOX ratio with densification.  Combined LOX/CH4 tanks are 31.21m long at 8.4m diameter (common tooling with SLS).  Actual external diameter > 8.4m due to insulation/shielding (micrometeoroid) and solar panels.  Assumed CBMs rated for stresses/loading with supplemental connection points.  Engine module is 8.68m long at 8.4 diameter.  Total length is 41.68m NOT including the upper module (aux control or cargo/fuel).
« Last Edit: 02/13/2016 11:05 PM by kaoru »

Offline Burninate

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Re: MCT Speculation and Discussion Thread 4
« Reply #1651 on: 02/13/2016 11:21 PM »
-snip-

* It's very difficult to parse your diagram.  You should illustrate some more of the things you're captioning.

* I'm not sure anyone really considers an 8.4m diameter plausible for this vehicle anymore.  What we know of the requirements imposed on the vehicle by most the mission architectures suggests there's too much rocket here for things to fit into 8.4m without making the vehicle extraordinarily long and thin and difficult to land.  We examined 10, 12.5, and 15 meters and mostly concluded that we were looking at the upper part of that range, just based on how big the BFR would need to be to get it into LEO.

* If you could include more of your figures and timelines for the mission architecture, we would be able to critique that a lot more productively.

It's nice to see more people thinking about the problem constructively, in any case.
« Last Edit: 02/13/2016 11:28 PM by Burninate »

Offline kaoru

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Re: MCT Speculation and Discussion Thread 4
« Reply #1652 on: 02/14/2016 12:29 AM »

* It's very difficult to parse your diagram.  You should illustrate some more of the things you're captioning.

* I'm not sure anyone really considers an 8.4m diameter plausible for this vehicle anymore.  What we know of the requirements imposed on the vehicle by most the mission architectures suggests there's too much rocket here for things to fit into 8.4m without making the vehicle extraordinarily long and thin and difficult to land.  We examined 10, 12.5, and 15 meters and mostly concluded that we were looking at the upper part of that range, just based on how big the BFR would need to be to get it into LEO.

* If you could include more of your figures and timelines for the mission architecture, we would be able to critique that a lot more productively.

It's nice to see more people thinking about the problem constructively, in any case.
Thank you, the intent is to think about the problem constructively.  I'm sure that Elon's MCT architecture will be completely different but you never know where ideas come from.

Yes, a picture is worth a thousand words, however, the cliche says nothing on how long it takes to document a visual idea from one's mind and put it a 3D model.  Unfortunately, a lot of time especially when your learning new software (aka SketchUp).  I would love to visualize the picture in my head, I just don't have the resources quite as yet.  This is a work in progress to be shared/worked on by all.

I'm more conservative regarding sizes (see my assumption about cost efficiencies).  8.4 diameter means existing tools and knowledge in handling, aka friction stir welding machines, transport (NASA Pegasus Barge), etc.  No matter how you slice and dice the numbers, you can't launch everything at one go.  Either you launch fuel, launch cargo, or launch butts-in-seats.  This "upper stage" is the common part to those three modes using the least amount of dry mass, reuse of proven technology, and within the limitations of existing/known infrastructure.  Going larger diameters may have devils in the details; it's the devils that are the problem.

This idea of an upper stage (but really a spacecraft in its own right) assumes a BFR first stage that's extremely large.  The engine module is not just 4 engines with a really good TWR and simple gimbal.  The engines have to adjust to the atmosphere or lack there of with best efficiencies.  The gimble/cant is for the different flight regimes.  For this reason, the module has to have a lot of structure for SRP (to cant the engines, heat shielding, deflectors), on orbit (IVF, ECLSS, pressurization, CBMs, pumps, shielding, insulation, extra baffles, etc.), and on Mars (cargo movement, fuel movement, airlock, "mud" room, immediately usable solar panels, etc.).  This is all dry mass so bigger means an even bigger first stage which I think is bordering on ridiculous.

As for figures and timelines, I concede that there are folks here better than me in such things.  My figures is based on a slew of posts and articles I've read, which I mashed together using first principals and simple calculations (mostly ratios of known values) to arrive at what I would call an "informed" guess.  Since I can't provide accreditation for everything and my figures are only guesses, I use them in my model but everything is up to interpretation.  Again it's a work-in-progress... Unfortunately, .skp files is not in the allowed file types for attachments.

Kaoru

Offline oldAtlas_Eguy

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Re: MCT Speculation and Discussion Thread 4
« Reply #1653 on: 02/14/2016 03:02 AM »
There is not really an such thing as a standard tank (LV) manufacturing equipment. Every provider uses a different machining/setup customized for the tank design even if it happens to be the same diameter of other providers. Making the diameter 8.4m will not save anything. The reasoning behind the SLS being 8.4m is that NASA was experienced with the handling of this size plus having existing transportation assets that is geared for that size. Since SpaceX's experience is with tanks of only 3.66m any size larger is equally plausible from a cost evaluation standpoint.

But here is the kicker. NASA's experience with tank manufacturing equipment for even the 8.4m tank size has been a significant problematic experience. SpaceX's design and subsequent manufacturing equipment design would evaluate the trade-offs between ease of manufacture/light weight/capitol costs into a solution that has the lowest life cycle costs development and operational costs. If you reuse each vehicle 10 times then slightly higher manufacturing costs are not as significant as other operational costs. So SpaceX assumption of the vehicle being operated sole as a reusable vehicle will weigh heavily on how it is designed and how it would be manufactured. Here is the assumptions on manufacturing the tank vertically or horizontally. A horizontally manufactured large diameter tank would be differently designed and possibly weigh more than a vertically manufactured tank like the SLS. Given the problems with getting the vertical manufacturing setup to stay in alignment it may be easier to do the manufacturing horizontally (lower floor weight support required, easier to maintain alignment).
« Last Edit: 02/14/2016 03:03 AM by oldAtlas_Eguy »

Offline kaoru

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Re: MCT Speculation and Discussion Thread 4
« Reply #1654 on: 02/14/2016 05:19 AM »
The problems experienced by NASA (Boeing is doing the tanks I believe at Michoud) is the devils in the details.  I chose 8.4 diameter to leverage the knowledge NASA has.  Of course, you could go with larger but why reinvent the wheel.  Also, dry mass is important for upper stages.  From my calculation, using NASA sleep station dimension plus some (5 cubic meters) per person.  Butts-in-seats (more like first class suite) for 100 passengers only require 500 cubic meters.  13.5m @ 8.4m dia. is 2993 cubic meters which is more than enough for passenger sleep stations, isles/passway, hygiene stations, common/work stations, and recreation stations (which includes ECLSS).  The consumables (fuel, water, air) come from tanker modules in something like the six shooter depot and/or the upper stage.  Note that the "six shooter" would never deorbit and require berths for the tankers, multi-CBM ports a la Unity, and a "auxiliary control" module.  Basically, the entire MCT is a train concept where everything is reusable that needs to be.

Here is an updated model showing the upper stage (the "engine room") and a basic tanker module.  The actual passenger module and auxiliary control module are still works-in-progress.

Note that the legs would have to be little more bigger/beefier with double articulation/shock absorbing.  What's picture is just a copy from another model I found.

Online guckyfan

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Re: MCT Speculation and Discussion Thread 4
« Reply #1655 on: 02/14/2016 08:30 AM »
If you reuse each vehicle 10 times then slightly higher manufacturing costs are not as significant as other operational costs. So SpaceX assumption of the vehicle being operated sole as a reusable vehicle will weigh heavily on how it is designed and how it would be manufactured.

Their declared goal is for 100 reuses. That's for the first stage obviously. A second stage MCT that goes to Mars will have less reuses. If the stage can do mixed service going to Mars and as a tanker they may get 50 reuses.

Offline john smith 19

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Re: MCT Speculation and Discussion Thread 4
« Reply #1656 on: 02/15/2016 01:01 AM »
I'm late to this but I wonder, apart from Karou's estimate has anyone looked at physically how 100 people lying down map into a cylinder? I'm guessing about 8'x3'. A square 8.2m gives 24 spaces, a circle is likely to give substantially less.

I expect the accumulated water, food and air will be much heavier than the passenger (without heavy recycling of all consumables) but occupy less volume (given the density of those items.
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Offline kaoru

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Re: MCT Speculation and Discussion Thread 4
« Reply #1657 on: 02/15/2016 02:09 AM »

I'm late to this but I wonder, apart from Karou's estimate has anyone looked at physically how 100 people lying down map into a cylinder? I'm guessing about 8'x3'. A square 8.2m gives 24 spaces, a circle is likely to give substantially less.

I expect the accumulated water, food and air will be much heavier than the passenger (without heavy recycling of all consumables) but occupy less volume (given the density of those items.
I got my numbers from NASA for the sleep stations on ISS.  I assume that if one can live aboard ISS for months on end, it's good for MCT passengers.  The sleep station is more than a bed, it doubles as a work/relaxation space. It doesn't have to be rectangle or box.  Think of it being an enclosed first class suite on a AirBus A380. 

A Dragon V2 has 10 cubic meters of pressurized space for seven people, 5 m3 for one person seems reasonable.   Layout of the stations would be interesting since you don't need floors in zero g.  The stations would have to be oriented for ascent/EDL and require access ways in gravity.

A good question is if the MCT will be used for temporary living space on Mars or just be a transport.

Kaoru

Offline Pipcard

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Re: MCT Speculation and Discussion Thread 4
« Reply #1658 on: 02/15/2016 02:41 AM »
5 m^3 per person is reasonable if the trip lasted a couple of weeks, but this is going to be at least 3-4 months or more.

Based on diagrams of the original Mars Direct plan, I had calculated the volume of the Earth Return Vehicle crew cabin for each of the four astronauts: 36 m^3. And for 6 months, that was thought to be too small.

ISS total habitable volume is 388 m^3. For 6-7 people (permanent crew, living on the station for months at a time), that is 55-65 m^3 per person.
« Last Edit: 02/15/2016 02:46 AM by Pipcard »

Offline kaoru

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Re: MCT Speculation and Discussion Thread 4
« Reply #1659 on: 02/15/2016 05:03 AM »
5 m^3 per person is reasonable if the trip lasted a couple of weeks, but this is going to be at least 3-4 months or more.

Based on diagrams of the original Mars Direct plan, I had calculated the volume of the Earth Return Vehicle crew cabin for each of the four astronauts: 36 m^3. And for 6 months, that was thought to be too small.

ISS total habitable volume is 388 m^3. For 6-7 people (permanent crew, living on the station for months at a time), that is 55-65 m^3 per person.
There's a difference between personal space and common space.  The personal space aboard the ISS is less than 5 m3, the rest is work space and Scott Kelly has gone almost a year with only that amount of personal space.  This is not an airplane, think of it more like a submarine with a lot more personal space (at least they're not hot racking).  AFAICR, ISS in the beginning didn't have (may still not have) not enough sleep stations; 2 stations I believe in the beginning for three astronauts.  One of them just had to sleep wherever they could be tied down.

Not sure about my previous post numbers, the cargo module (top; shown in attachment) is 13m by 8.4 dia cylinder with a 12m cone which is a pressure vessel of 720 m3 + 221 m3 = 941 m3.  Obviously, some of that is taken up by mechanicals and such but there should be a good chunk left over.  Of course, my concept is modular so there's no reason why a BA330 couldn't be added to the MCT.

I'm interested in modelling what the passenger module would look like.  Note that my "engineering" service module has most of the mechanicals for the passenger module.  I'm still working on the models, but here is what I envision as MCT would be (using a "train" paradigm):

Service Module #1 (as shown in attachment) -> Service Module #2 -> Service Module #3 -> Fuel/Consumables Carrier (never lands; contains tanker/cargo modules that can land w/ service module) -> Orbital Habitat Module (i.e. BA330; never lands) -> "Aux Control" module (for on orbit ops; never lands) -> Passenger Module (lands w service module).

At Earth:  Launch modules aux. control, module carrier, and orbital habitat module (i.e.) with two service modules kept in orbit.  Launch fuel & cargo modules to fill up service modules and carrier.  Launch passenger module, service module refuels.  All modules are now in orbit and ready to depart to Mars.

At Mars:  Enter Mars orbit.  Service Module #1 -> Cargo module is lander #1.  Service Module #2 -> Passenger Module is lander #2.  Both land at landing site.

That's an example regime from my ideas.  Here's the updated model (by no means finished) with sudo-Raptors (vacuum nozzle minus extension) added; I haven't put the nacelles on.
« Last Edit: 02/15/2016 06:26 AM by kaoru »

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