ITS Environmental Control and Life Support System (ECLSS)

[sghill]

Despite Elon’s assertion that the ride on the ITS will "be, like, really fun to go," living aboard the vehicle will be dangerous and decidedly not fun if the types of ECLSS we use on board the space station are utilized on ITS.

Supporting 100 people for months in zero-g requires new systems and techniques.  100 bored passengers needing to eat, poop, and clean themselves are going to be a mess.

IMHO, the basic problem of no up and down in a weightless living environment needs to be addressed. 100 people can’t have non-flushing toilets, no ability to move fluids down a drain, and no ability to cook for dozens several times a day.  OK, cooking isn’t so important, but the space shuttle used to return after two weeks with seven people on board with filth everywhere- and on every possible surface. Space shuttle also dumped its fluids. ITS needs a recycling system and holding tanks 10 times the size of the one on ISS. I don’t see these elements in ITS renderings.

Furthermore, the situation is further complicated because whatever system they come up with must function properly in both weightlessness and in Mars gravity. It also must be simple enough to avoid a catastrophic failure and be repaired during a flight. In other words, they need simple toilets, a functioning galley, and a septic system that operate in both environments.

So how is this accomplished, what will SpaceX's ECLSS look like, and how do we fill in the blank areas in the rendering below with realistic support systems?

[On a personal note, I’d like to think Elon’s upcoming reveal is that they’ll use a tether system to generate low gravity between two ITS ships traveling back and forth to Mars. It makes the above challenges easier IMHO.]

[jpo234]

Supporting 100 people for months in zero-g requires new systems and techniques.  100 bored passengers needing to eat, poop, and clean themselves are going to be a mess.

I don't think that this is a high priority item for SpaceX. Initially we will mostly see unmanned freighters and manned ships with a relatively small exploration crew (less than 20, I assume). That's based on Paul Woosters recent presentation were he said: "We have a lot of margin for early missions, which is quite helpful.". "a lot of margin" IMHO precludes 100 passengers.

So, an ECLSS for 100 passengers is something that will need to happen after the "early missions". When do the early missions end? My guess is at least 20 years after the first one. At that point SpaceX could be well on its way to the ships that make the initial ITS "look like a rowboat". So, trying to fit an ECLSS for 100 passengers into the initial ITS version is something that might never happen.

[redliox]

Supporting 100 people for months in zero-g requires new systems and techniques.  100 bored passengers needing to eat, poop, and clean themselves are going to be a mess.

I don't think that this is a high priority item for SpaceX. Initially we will mostly see unmanned freighters and manned ships with a relatively small exploration crew (less than 20, I assume). That's based on Paul Woosters recent presentation were he said: "We have a lot of margin for early missions, which is quite helpful.". "a lot of margin" IMHO precludes 100 passengers.

Right - it's going to be a while yet before we see 100-person crews.  It is indeed going to be a massive pain supporting 100 people for 6-month-some voyagers...but developing an ECLSS precursor that can handle something in the 5-20 person range ought to be possible and also possible to incrementally refine.  It will likely take a combination of NASA input and SpaceX's 'aggressive persistence' to go from 5 to finally 100.

In the meantime, I've heard water recycling is approaching 100% although I doubt it has the capacity to handle 100 people, and oxygen recycling is something like 50% (probably varies depending on what system utilized).  The practice between the STS and ISS seems to be paying off, and even without artificial gravity I believe we could handle a trip to Mars now with the following guidelines:

-Crew of less than 10
-Keep the inbound/outbound trips under 9 months
-Habitat with supplies awaiting at Mars

[RonM]

Nice thing about early missions with a small crew is the very large cargo capacity. Extra life support supplies such as oxygen and water to replenish ECLSS can be carried. Spare parts too. Of course, that won't work with 100 people on board, but there will be many years to develop large capacity systems.

[sghill]

Supporting 100 people for months in zero-g requires new systems and techniques.  100 bored passengers needing to eat, poop, and clean themselves are going to be a mess.

I don't think that this is a high priority item for SpaceX. Initially we will mostly see unmanned freighters and manned ships with a relatively small exploration crew (less than 20, I assume). That's based on Paul Woosters recent presentation were he said: "We have a lot of margin for early missions, which is quite helpful.". "a lot of margin" IMHO precludes 100 passengers.

Right - it's going to be a while yet before we see 100-person crews.  It is indeed going to be a massive pain supporting 100 people for 6-month-some voyagers...but developing an ECLSS precursor that can handle something in the 5-20 person range ought to be possible and also possible to incrementally refine.  It will likely take a combination of NASA input and SpaceX's 'aggressive persistence' to go from 5 to finally 100.

The initial crew size is a strawman argument. They've got to design the spacecraft now for maximum crew size.  ECLSS isn't something that is bolted on board and changes with crew sizes. Plumbing and storage tanks will be integral to the design from Day 1.

If it's easier on the systems with a smaller crew sobeit, but that doesn't change the immediacy of the design need.

[DanielW]

If you make a per deck modular system, or two per deck, then the only thing that needs to be full scale on early flights is the Atmosphere handling system. Fans and Ducts to avoid dead spaces. Then you only need to outfit one deck with CO2 scrubbing, Oxygen generation, Lavatories etc for early missions. But yes space will need to be allocated to install systems on each deck.

Conversely there are probably economies of scale, with regards to mass, that dictate that you should build it all at once.

[JamesH65]

Supporting 100 people for months in zero-g requires new systems and techniques.  100 bored passengers needing to eat, poop, and clean themselves are going to be a mess.

I don't think that this is a high priority item for SpaceX. Initially we will mostly see unmanned freighters and manned ships with a relatively small exploration crew (less than 20, I assume). That's based on Paul Woosters recent presentation were he said: "We have a lot of margin for early missions, which is quite helpful.". "a lot of margin" IMHO precludes 100 passengers.

Right - it's going to be a while yet before we see 100-person crews.  It is indeed going to be a massive pain supporting 100 people for 6-month-some voyagers...but developing an ECLSS precursor that can handle something in the 5-20 person range ought to be possible and also possible to incrementally refine.  It will likely take a combination of NASA input and SpaceX's 'aggressive persistence' to go from 5 to finally 100.

The initial crew size is a strawman argument. They've got to design the spacecraft now for maximum crew size.  ECLSS isn't something that is bolted on board and changes with crew sizes. Plumbing and storage tanks will be integral to the design from Day 1.

If it's easier on the systems with a smaller crew sobeit, but that doesn't change the immediacy of the design need.

I think I disagree. They could have some idea of the final volume required, but they don't need to fill it with the full version - that could be retrofitted later.

[RonM]

Supporting 100 people for months in zero-g requires new systems and techniques.  100 bored passengers needing to eat, poop, and clean themselves are going to be a mess.

I don't think that this is a high priority item for SpaceX. Initially we will mostly see unmanned freighters and manned ships with a relatively small exploration crew (less than 20, I assume). That's based on Paul Woosters recent presentation were he said: "We have a lot of margin for early missions, which is quite helpful.". "a lot of margin" IMHO precludes 100 passengers.

Right - it's going to be a while yet before we see 100-person crews.  It is indeed going to be a massive pain supporting 100 people for 6-month-some voyagers...but developing an ECLSS precursor that can handle something in the 5-20 person range ought to be possible and also possible to incrementally refine.  It will likely take a combination of NASA input and SpaceX's 'aggressive persistence' to go from 5 to finally 100.

The initial crew size is a strawman argument. They've got to design the spacecraft now for maximum crew size.  ECLSS isn't something that is bolted on board and changes with crew sizes. Plumbing and storage tanks will be integral to the design from Day 1.

If it's easier on the systems with a smaller crew sobeit, but that doesn't change the immediacy of the design need.

It would be wise to plan ahead. However, the crew area is very large and can be significantly modified. SpaceX can move to more of an airplane model as far as crew interior design is concerned.

[Negan]

Had the same questions too. Found this paper that spells out the fundamentals in detail. I agree with others that 100 is the goal, but won't be a gating item for the first missions.

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100036823.pdf

[Norm38]

Why would water vapor be dumped to atmosphere only to be scrubbed back out?  With a bunch of people breathing and sweating (exercise), bathing, I don't think low humidity will be a problem.

[Tomness]

100 people won't be habitating in these things, they will be asleep

[docmordrid]

100 people won't be habitating in these things, they will be asleep

ISTM that initially torpor won't yet be proven for months long voyages so do it in shifts, perhaps 2-3 weeks at a time, with medical staff also in rotation for addressing problems.

[sghill]

Supporting 100 people for months in zero-g requires new systems and techniques.  100 bored passengers needing to eat, poop, and clean themselves are going to be a mess.

I don't think that this is a high priority item for SpaceX. Initially we will mostly see unmanned freighters and manned ships with a relatively small exploration crew (less than 20, I assume). That's based on Paul Woosters recent presentation were he said: "We have a lot of margin for early missions, which is quite helpful.". "a lot of margin" IMHO precludes 100 passengers.

Right - it's going to be a while yet before we see 100-person crews.  It is indeed going to be a massive pain supporting 100 people for 6-month-some voyagers...but developing an ECLSS precursor that can handle something in the 5-20 person range ought to be possible and also possible to incrementally refine.  It will likely take a combination of NASA input and SpaceX's 'aggressive persistence' to go from 5 to finally 100.

The initial crew size is a strawman argument. They've got to design the spacecraft now for maximum crew size.  ECLSS isn't something that is bolted on board and changes with crew sizes. Plumbing and storage tanks will be integral to the design from Day 1.

If it's easier on the systems with a smaller crew sobeit, but that doesn't change the immediacy of the design need.

I think I disagree. They could have some idea of the final volume required, but they don't need to fill it with the full version - that could be retrofitted later.

That is impractical with a production run that can be counted on one hand. They're not building 737's (or even Falcon 9's) and then stretched versions after numerous unit sales. The initial version is the final version.

100 people won't be habitating in these things, they will be asleep

Source for that statement please. If we could do that now, we'd have tested it on ISS- or at least heard of it being done in the news.

It would be wise to plan ahead. However, the crew area is very large and can be significantly modified. SpaceX can move to more of an airplane model as far as crew interior design is concerned.

Take a look at a space shuttle schematic. The crew interior area is not dominated by plumbing and fixtures, it's dominated by storage lockers and open space. Everything else is behind the walls and in the floors and ceilings. That part has to be designed from the outset because it affects structure, COG, the design of the pressure wessel, and how the thing is constructed.

And if anything, Elon Musk has proven again and again across all of his companies that he builds the capability of future upgrades into his designs even if he doesn't have them on future versions. 

So, yes, the ECLSS system may be smaller on the first flight, but the time and the expense of this machine dictates it will move to 100 passengers as soon as habitat systems on Mars can support their arrival. 

Ergo, a scaled version of ECLSS is still a strawman argument that makes little business sense. Furthermore, because the ECLSS is a mission critical component, it's not something that's going to be retrofitted in after the first flight. Retrofitting, testing, and validation would require missing a launch window to make a modification that could have been baked in from the start.
This thread is intended to discuss the needs and systems that address those needs, and not how fast the needs are realized.

[Kaputnik]

The ITS ship is capable of being built as a tanker, speculatively as an Earth-orbit sat launcher, as a Mars carg lander, as a combined cargo/crew lander, and as a pure crew lander. That is a lot of different configurations.

IMHO they could take the unmanned cargo lander design and bolt on the necessary ECLSS to support a minimal pioneer crew, without any detriment to the eventual 100-person design.

[RonM]

Something like the International Standard Payload Rack used on ISS would make it easy to reconfigure ITS spacecraft. Might be useful if the racks were a little bigger (whatever can fit through the larger hatch). Every detail of the ECLSS doesn't have to be decided from the start if there are equipment racks that can be swapped out.

[AncientU]

Supporting 100 people for months in zero-g requires new systems and techniques.  100 bored passengers needing to eat, poop, and clean themselves are going to be a mess.

I don't think that this is a high priority item for SpaceX. Initially we will mostly see unmanned freighters and manned ships with a relatively small exploration crew (less than 20, I assume). That's based on Paul Woosters recent presentation were he said: "We have a lot of margin for early missions, which is quite helpful.". "a lot of margin" IMHO precludes 100 passengers.

Right - it's going to be a while yet before we see 100-person crews.  It is indeed going to be a massive pain supporting 100 people for 6-month-some voyagers...but developing an ECLSS precursor that can handle something in the 5-20 person range ought to be possible and also possible to incrementally refine.  It will likely take a combination of NASA input and SpaceX's 'aggressive persistence' to go from 5 to finally 100.

The initial crew size is a strawman argument. They've got to design the spacecraft now for maximum crew size.  ECLSS isn't something that is bolted on board and changes with crew sizes. Plumbing and storage tanks will be integral to the design from Day 1.

If it's easier on the systems with a smaller crew sobeit, but that doesn't change the immediacy of the design need.

I think I disagree. They could have some idea of the final volume required, but they don't need to fill it with the full version - that could be retrofitted later.

I know I don't agree.  Maybe you are picturing one of these classical waterfall design and build efforts that takes decades and armies... SpaceX is quite nimble and can easily evolve the balance between travelers supported and cargo carried.  The ECLSS, for instance could be modular, where one unit was capable of handling 10 travelers.  Build three units for redundancy, and use remaining mass/volume budget for surface cargo, supplies, whatever.  As the number on board increases, increase the ECLSS modules, always keeping sufficient spares for redundancy needs.

As a bonus, any modular systems can be left on Mars instead of being lugged back to Earth needlessly when they could have been used on Mars.

[Robotbeat]

100 people won't be habitating in these things, they will be asleep

ISTM that initially torpor won't yet be proven for months long voyages so do it in shifts, perhaps 2-3 weeks at a time, with medical staff also in rotation for addressing problems.

This is for the 500 passenger variant of ITS, not the 10-100 variant.

[su27k]

Supporting 100 people for months in zero-g requires new systems and techniques.  100 bored passengers needing to eat, poop, and clean themselves are going to be a mess.

I don't think that this is a high priority item for SpaceX. Initially we will mostly see unmanned freighters and manned ships with a relatively small exploration crew (less than 20, I assume). That's based on Paul Woosters recent presentation were he said: "We have a lot of margin for early missions, which is quite helpful.". "a lot of margin" IMHO precludes 100 passengers.

Right - it's going to be a while yet before we see 100-person crews.  It is indeed going to be a massive pain supporting 100 people for 6-month-some voyagers...but developing an ECLSS precursor that can handle something in the 5-20 person range ought to be possible and also possible to incrementally refine.  It will likely take a combination of NASA input and SpaceX's 'aggressive persistence' to go from 5 to finally 100.

The initial crew size is a strawman argument. They've got to design the spacecraft now for maximum crew size.  ECLSS isn't something that is bolted on board and changes with crew sizes. Plumbing and storage tanks will be integral to the design from Day 1.

If it's easier on the systems with a smaller crew sobeit, but that doesn't change the immediacy of the design need.

They can redesign it later. I mean how can anyone expect them to come up with the final design on first try, given how many iterations Falcon 9 (and to a less degree, Dragon) has gone though? The first ITS would be like the first Falcon 9/Dragon, which they later joked they didn't know what they were doing, the 100 people ITS would be like Block 5/Dragon 2.

[MP99]

I still like the idea of an open loop system - use the carbohydrates in the food (reclaimed from CO2, water vapour, liquid and solid wastes) to create methalox which then gets dumped in the prop tanks.

The mass saved in prop at TMI could then be retasked to consumables.

Of course, this doesn't make for a simple system (no such thing exists when it comes to ECLSS) but it does reduce the level of recycling which is required to survive the flight.

Cheers, Martin

Cheers, Martin

[IRobot]

My guess is that the 100 passengers number is the same as the Airbus A-380 +800 passengers.
In reality, no company operates it at full capacity, usually they use less than 60%.

My guess is that passengers will mostly book premium passages, with more room, so less pressure on ECLSS.

My prediction for the initial crew is around 12. Several Mars mission proposals have stated that +6 would be ideal and I think SpaceX wants to put up a mission with more crew members than NASA could ever dream by 2030's. So 12.

Also if the initial mission is 100% privately funded (doubt that), it will have some sort of a reality show thing to it, so more characters, more interest it gathers.