Author Topic: The fate of SLS after Falcon Heavy debut  (Read 34875 times)

Offline Deep_Space_Housecat

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Re: The fate of SLS after Falcon Heavy debut
« Reply #180 on: 02/14/2018 12:28 pm »
What does that mean? We have delays in development? So what? Falcon Heavy was 5 years late. Welcome to the space business.

The point is not the delay but the utter lack of payloads that could actually use the unique capabilities of SLS.
It's true we do not know exactly what payloads the SLS will carry. That's because they haven't been built, yet, but they will be. And we do know the payloads for a Human Mars expedition are going to be heavy. Very heavy. Far, far, heavier than anything we have sent to Mars before, like the rovers.

Falcon Heavy is designed to put satellites into low earth orbit. SLS is in a different league.

Offline su27k

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Re: The fate of SLS after Falcon Heavy debut
« Reply #181 on: 02/14/2018 12:38 pm »
How do you think the successful flight of Falcon Heavy will impact SLS? Will there be consequences? Will development of the rocket continue as planned, will the status quo will be maintained?

Or is there any chance for the Adminstration to redirect the Lunar efforts to Falcon Heavy?
I do not think the Falcon Heavy flight will effect the SLS at all. The SLS is a much more capable rocket and should continue to move forward as planned.

Is it?

https://twitter.com/SciGuySpace/status/963493015091326977

Quote
SLS maiden launch slips to 2020. That's three years to the right, at a cost of about $7 billion. For comparative purposes, NASA could buy nearly 80 Falcon Heavy launches for that price. SpaceX might even give 'em a bulk discount.
Yes, I think so.

If Wikipedia is correct, the SLS has more than double the payload capacity to LEO. Falcon Heavy does not compete in lift capacity.

The "more than double the payload capacity" version of SLS is Block 2, which wouldn't be ready until 2028 at the earliest. SLS Block 1B has less than double the payload capacity, it wouldn't be ready until 2023 (i.e. 5 years from now). What is flying in 2020 is the SLS Block 1 which is 70t to LEO, about 6t more capable than FH, and just for this 6 extra tons you're willing to pay $7 billion?
« Last Edit: 02/14/2018 12:39 pm by su27k »

Offline envy887

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Re: The fate of SLS after Falcon Heavy debut
« Reply #182 on: 02/14/2018 12:39 pm »
What does that mean? We have delays in development? So what? Falcon Heavy was 5 years late. Welcome to the space business.

The point is not the delay but the utter lack of payloads that could actually use the unique capabilities of SLS.
It's true we do not know exactly what payloads the SLS will carry. That's because they haven't been built, yet, but they will be. And we do know the payloads for a Human Mars expedition are going to be heavy. Very heavy. Far, far, heavier than anything we have sent to Mars before, like the rovers.

Falcon Heavy is designed to put satellites into low earth orbit. SLS is in a different league.

SLS Block 1 and Block 1B are far too small for single-launch manned missions to the Moon or Mars surface. Even Block 2 would just barely be large enough for a Moon mission, but is still too small for Mars.

Any sustained missions to the Moon or Mars will require distributed lift. SLS with its atrocious flight rate and cost per kg has no part in any distributed lift scheme. It's much simpler and cheaper to repurpose commercial vehicles.

Online Robotbeat

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Re: The fate of SLS after Falcon Heavy debut
« Reply #183 on: 02/14/2018 12:47 pm »
How do you think the successful flight of Falcon Heavy will impact SLS? Will there be consequences? Will development of the rocket continue as planned, will the status quo will be maintained?

Or is there any chance for the Adminstration to redirect the Lunar efforts to Falcon Heavy?
I do not think the Falcon Heavy flight will effect the SLS at all. The SLS is a much more capable rocket and should continue to move forward as planned.

Is it?

https://twitter.com/SciGuySpace/status/963493015091326977

Quote
SLS maiden launch slips to 2020. That's three years to the right, at a cost of about $7 billion. For comparative purposes, NASA could buy nearly 80 Falcon Heavy launches for that price. SpaceX might even give 'em a bulk discount.
Yes, I think so.

If Wikipedia is correct, the SLS has more than double the payload capacity to LEO. Falcon Heavy does not compete in lift capacity.

Imagine NASA purchasing 5 FH launches for $500mln and spending the remaining $6.5bn on payloads for them. They could fund and launch 5 missions in the Cassini/New Horizon/Juno class just from the current budget.
If I'm putting people on a round trip to Mars, I want to do that with as few launches as possible. Launches are risky, and I like as few risks as possible. Especially in human spaceflight. I'd go with the SLS.

And it's not a very fair comparison to compare the entire development cost of the SLS to the speculative per launch cost of the Falcon Heavy. 

The SLS and Falcon Heavy are different rockets with different missions. The SLS has a much more ambitious objective. Putting people on a round trip to Mars. I don't expect their cost to compare.
Ya got that backwards. If you’re launching people to Mars, you want to launch them on a rocket family that flies super often for safety reasons. If you fly a rocket once every couple years, not going to be safe enough. And for the cargo: don’t want all of your eggs in one, rarely-launched (and therefore high-risk) basket.

63tons is very close to the 70tons of the initial SLS. The 100 ton SLS won’t be flying until at least 2023 (after BFR), and the heavier SLS block 2 for 120-140 tons just got cut from future plans in the Trump budget (if I hear correctly).
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Offline woods170

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Re: The fate of SLS after Falcon Heavy debut
« Reply #184 on: 02/14/2018 12:56 pm »
Is it?

https://twitter.com/SciGuySpace/status/963493015091326977

Quote
SLS maiden launch slips to 2020. That's three years to the right, at a cost of about $7 billion. For comparative purposes, NASA could buy nearly 80 Falcon Heavy launches for that price. SpaceX might even give 'em a bulk discount.
Yes, I think so.

If Wikipedia is correct, the SLS has more than double the payload capacity to LEO. Falcon Heavy does not compete in lift capacity.

Tell me... When was the last time there was a 130 MT payload ready for SLS. Or a 105 MT payload? Or a 70 MT payload?

The answer is never.


What does that mean? We have delays in development? So what? Falcon Heavy was 5 years late. Welcome to the space business.
 
What it means is that there are no payloads - planned or existing - other than Orion that justify the existence of SLS.
The only raison d être for SLS is Orion. Everything else can be done by existing commercial launchers given that there are no single-piece payloads (again: other than Orion) that can be lifted by SLS only.
« Last Edit: 02/14/2018 12:58 pm by woods170 »

Offline woods170

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Re: The fate of SLS after Falcon Heavy debut
« Reply #185 on: 02/14/2018 01:03 pm »
What does that mean? We have delays in development? So what? Falcon Heavy was 5 years late. Welcome to the space business.

The point is not the delay but the utter lack of payloads that could actually use the unique capabilities of SLS.
It's true we do not know exactly what payloads the SLS will carry. That's because they haven't been built, yet, but they will be. And we do know the payloads for a Human Mars expedition are going to be heavy. Very heavy. Far, far, heavier than anything we have sent to Mars before, like the rovers.

You state it yourself: the payloads don't exist. They are not even being designed yet. Which means that the bolded part of your post is one massive assumption.

Offline Deep_Space_Housecat

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Re: The fate of SLS after Falcon Heavy debut
« Reply #186 on: 02/14/2018 01:12 pm »
How do you think the successful flight of Falcon Heavy will impact SLS? Will there be consequences? Will development of the rocket continue as planned, will the status quo will be maintained?

Or is there any chance for the Adminstration to redirect the Lunar efforts to Falcon Heavy?
I do not think the Falcon Heavy flight will effect the SLS at all. The SLS is a much more capable rocket and should continue to move forward as planned.

Is it?

https://twitter.com/SciGuySpace/status/963493015091326977

Quote
SLS maiden launch slips to 2020. That's three years to the right, at a cost of about $7 billion. For comparative purposes, NASA could buy nearly 80 Falcon Heavy launches for that price. SpaceX might even give 'em a bulk discount.
Yes, I think so.

If Wikipedia is correct, the SLS has more than double the payload capacity to LEO. Falcon Heavy does not compete in lift capacity.

The "more than double the payload capacity" version of SLS is Block 2, which wouldn't be ready until 2028 at the earliest. SLS Block 1B has less than double the payload capacity, it wouldn't be ready until 2023 (i.e. 5 years from now). What is flying in 2020 is the SLS Block 1 which is 70t to LEO, about 6t more capable than FH, and just for this 6 extra tons you're willing to pay $7 billion?
The SLS is designed to put humans back into space. Deep space. A new opening of human space exploration. That's what it is designed for.

The Falcon Heavy is not going to carry people. Never, ever. Just satellites to LEO. That's what it is designed for.

You want to go to Mars, the Moon, or an Asteroid, with people? Then you're going on a SLS, or you're not going.

Apples and oranges.

Offline Eerie

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Re: The fate of SLS after Falcon Heavy debut
« Reply #187 on: 02/14/2018 01:17 pm »
How do you think the successful flight of Falcon Heavy will impact SLS? Will there be consequences? Will development of the rocket continue as planned, will the status quo will be maintained?

Or is there any chance for the Adminstration to redirect the Lunar efforts to Falcon Heavy?
I do not think the Falcon Heavy flight will effect the SLS at all. The SLS is a much more capable rocket and should continue to move forward as planned.

Is it?

https://twitter.com/SciGuySpace/status/963493015091326977

Quote
SLS maiden launch slips to 2020. That's three years to the right, at a cost of about $7 billion. For comparative purposes, NASA could buy nearly 80 Falcon Heavy launches for that price. SpaceX might even give 'em a bulk discount.
Yes, I think so.

If Wikipedia is correct, the SLS has more than double the payload capacity to LEO. Falcon Heavy does not compete in lift capacity.

The "more than double the payload capacity" version of SLS is Block 2, which wouldn't be ready until 2028 at the earliest. SLS Block 1B has less than double the payload capacity, it wouldn't be ready until 2023 (i.e. 5 years from now). What is flying in 2020 is the SLS Block 1 which is 70t to LEO, about 6t more capable than FH, and just for this 6 extra tons you're willing to pay $7 billion?
The SLS is designed to put humans back into space. Deep space. A new opening of human space exploration. That's what it is designed for.

The Falcon Heavy is not going to carry people. Never, ever. Just satellites to LEO. That's what it is designed for.

You want to go to Mars, the Moon, or an Asteroid, with people? Then you're going on a SLS, or you're not going.

Apples and oranges.

Never, ever? Wut?

SLS is a rocket, Falcon Heavy is a rocket. Both can be certified to carry humans in space, if necessary.

Offline envy887

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Re: The fate of SLS after Falcon Heavy debut
« Reply #188 on: 02/14/2018 01:21 pm »
How do you think the successful flight of Falcon Heavy will impact SLS? Will there be consequences? Will development of the rocket continue as planned, will the status quo will be maintained?

Or is there any chance for the Adminstration to redirect the Lunar efforts to Falcon Heavy?
I do not think the Falcon Heavy flight will effect the SLS at all. The SLS is a much more capable rocket and should continue to move forward as planned.

Is it?

https://twitter.com/SciGuySpace/status/963493015091326977

Quote
SLS maiden launch slips to 2020. That's three years to the right, at a cost of about $7 billion. For comparative purposes, NASA could buy nearly 80 Falcon Heavy launches for that price. SpaceX might even give 'em a bulk discount.
Yes, I think so.

If Wikipedia is correct, the SLS has more than double the payload capacity to LEO. Falcon Heavy does not compete in lift capacity.

The "more than double the payload capacity" version of SLS is Block 2, which wouldn't be ready until 2028 at the earliest. SLS Block 1B has less than double the payload capacity, it wouldn't be ready until 2023 (i.e. 5 years from now). What is flying in 2020 is the SLS Block 1 which is 70t to LEO, about 6t more capable than FH, and just for this 6 extra tons you're willing to pay $7 billion?
The SLS is designed to put humans back into space. Deep space. A new opening of human space exploration. That's what it is designed for.

The Falcon Heavy is not going to carry people. Never, ever. Just satellites to LEO. That's what it is designed for.

You want to go to Mars, the Moon, or an Asteroid, with people? Then you're going on a SLS, or you're not going.

Apples and oranges.

Wrong. Falcon Heavy is designed to be human rated. It can carry crew.

Offline jpo234

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Re: The fate of SLS after Falcon Heavy debut
« Reply #189 on: 02/14/2018 01:24 pm »
The SLS is designed to put humans back into space. Deep space. A new opening of human space exploration. That's what it is designed for.

There is no deep space habitat. You can't do long duration missions in a small capsule (e.g. Orion).

The Falcon Heavy is not going to carry people. Never, ever. Just satellites to LEO. That's what it is designed for.

FH could launch people. In fact, SpaceX planned to, but is now convinced that BFR will make that obsolete. And: I doubt that FH will ever put satellites into LEO(1). It's bread and butter market are big GEO satellites.

You want to go to Mars, the Moon, or an Asteroid, with people? Then you're going on a SLS, or you're not going.

Apples and oranges.

There are New Glenn, New Armstrong and BFR in the pipeline. At least one of them will deliver.

(1) unless it's larger fairing makes StarLink launches economically viable.
« Last Edit: 02/14/2018 01:26 pm by jpo234 »
You want to be inspired by things. You want to wake up in the morning and think the future is going to be great. That's what being a spacefaring civilization is all about. It's about believing in the future and believing the future will be better than the past. And I can't think of anything more exciting than being out there among the stars.

Offline jpo234

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Re: The fate of SLS after Falcon Heavy debut
« Reply #190 on: 02/14/2018 01:32 pm »
Imagine NASA purchasing 5 FH launches for $500mln and spending the remaining $6.5bn on payloads for them. They could fund and launch 5 missions in the Cassini/New Horizon/Juno class just from the current budget.

https://arstechnica.com/science/2018/02/three-years-of-sls-development-could-buy-86-falcon-heavy-launches/

Quote
For the sake of argument, consider the costs of this three-year delay against the lift capability NASA could have bought by purchasing Falcon Heavy rockets from SpaceX in 2018, 2019, and 2020. That $7.8 billion equates to 86 launches of the reusable Falcon Heavy or 52 of the expendable version. This provides up to 3,000 tons of lift—the equivalent of eight International Space Stations or one heck of a Moon base. Obviously NASA does not need that many launches, but it could buy several Falcon Heavy rockets a year and have the funds to build meaningful payloads to launch on them.

Just what I said...
You want to be inspired by things. You want to wake up in the morning and think the future is going to be great. That's what being a spacefaring civilization is all about. It's about believing in the future and believing the future will be better than the past. And I can't think of anything more exciting than being out there among the stars.

Offline Deep_Space_Housecat

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Re: The fate of SLS after Falcon Heavy debut
« Reply #191 on: 02/14/2018 01:33 pm »
The SLS is designed to put humans back into space. Deep space. A new opening of human space exploration. That's what it is designed for.

There is no deep space habitat. You can't do long duration missions in a small capsule (e.g. Orion).

The Falcon Heavy is not going to carry people. Never, ever. Just satellites to LEO. That's what it is designed for.

FH could launch people. In fact, SpaceX planned to, but is now convinced that BFR will make that obsolete. And: I doubt that FH will ever put satellites into LEO(1). It's bread and butter market are big GEO satellites.

You want to go to Mars, the Moon, or an Asteroid, with people? Then you're going on a SLS, or you're not going.

Apples and oranges.

There are New Glenn, New Armstrong and BFR in the pipeline. At least one of them will deliver.

(1) unless it's larger fairing makes StarLink launches economically viable.
People will never sit on top of a Falcon Heavy and ride it anywhere. SpaceX has already said this. It's easy to say we are going to do this and that but delivering is the thing you see.

SLS is going to deliver.

Offline jpo234

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Re: The fate of SLS after Falcon Heavy debut
« Reply #192 on: 02/14/2018 01:37 pm »
People will never sit on top of a Falcon Heavy and ride it anywhere. SpaceX has already said this. It's easy to say we are going to do this and that but delivering is the thing you see.

Let's hope there will never be a manned FH. This would mean that BFR stays on target.

SLS is going to deliver.

Once or twice.
You want to be inspired by things. You want to wake up in the morning and think the future is going to be great. That's what being a spacefaring civilization is all about. It's about believing in the future and believing the future will be better than the past. And I can't think of anything more exciting than being out there among the stars.

Re: The fate of SLS after Falcon Heavy debut
« Reply #193 on: 02/14/2018 01:43 pm »
The SLS was developed under the assumption that BEO is NASA's exclusive territory. That's clearly not true anymore, and FH is not an outlier, it's just the beginning. SpaceX is not alone too.
The BEO missions that are being developed for SLS should be redesigned to leverage new commercial capabilites.

NASA has time: at the current pace those plans for cislunar space, never mind Mars won't concretize into actual launches until 2024 at best. Comparable commercial capability starts NOW with Falcon Heavy, and its redundancy and scope will keep evolving and expanding with new systems and players at a pace that will always see SLS behind.
Vulcan and New Glenn in 2020-2021, the outstanding capacity and low cost of BFR, ULA ACES in 2024: all of them are likely to come before SLS flies operationally and almost certainly before Block 2. Those have one thing in common: they're designed for reusability and sustainability, key in developing viable BEO architectures, something that NASA couldn't do with its budget and the costly SLS.

Nasa has to cancel this program and change their plans to leverage those capabilities NOW. They don't even have to pay for their development, all it takes is supporting them with BEO missions.
Not only they would accomplish the same missions as with SLS (even if it takes more launches), they would probably do so cheaper, faster and, most importantly the returns to the broader US space community would be huge.

NASA would nurture and help the development of a thriving commercial ecosystem, founded upon reusability and accessibility, with the potential of expanding way beyond what NASA envisions with SLS.
Ditching the SLS would free up resources to develop actual missions that leverage these new commercial capabilities and at the same time financing the deployment of new technologies that would usher us into a new era of spaceflight.

That's the only way we can establish a sustainable presence in cislunar space, on the moon and on Mars: with a thriving commercial ecosystem, which intrinsically provides cheap and viable architectures for BEO human spaceflight. With the SLS we are not going to Mars, we are not going to exploit cislunar space.

NASA has to play a role in this, that's what an agency that has enabling and expanding human spaceflight as a goal should do.
« Last Edit: 02/14/2018 01:53 pm by AbuSimbel »
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Offline Deep_Space_Housecat

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Re: The fate of SLS after Falcon Heavy debut
« Reply #194 on: 02/14/2018 01:43 pm »
People will never sit on top of a Falcon Heavy and ride it anywhere. SpaceX has already said this. It's easy to say we are going to do this and that but delivering is the thing you see.

Let's hope there will never be a manned FH. This would mean that BFR stays on target.

SLS is going to deliver.

Once or twice.
That would be once or twice more than a BFR will ever fly.
« Last Edit: 02/14/2018 01:44 pm by Deep_Space_Housecat »

Offline jpo234

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Re: The fate of SLS after Falcon Heavy debut
« Reply #195 on: 02/14/2018 01:47 pm »
That would be once or twice more than a BFR will ever fly.

If not BFR, then New Armstrong.
« Last Edit: 02/14/2018 01:59 pm by jpo234 »
You want to be inspired by things. You want to wake up in the morning and think the future is going to be great. That's what being a spacefaring civilization is all about. It's about believing in the future and believing the future will be better than the past. And I can't think of anything more exciting than being out there among the stars.

Online Robotbeat

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Re: The fate of SLS after Falcon Heavy debut
« Reply #196 on: 02/14/2018 01:58 pm »
People will never sit on top of a Falcon Heavy and ride it anywhere. SpaceX has already said this. It's easy to say we are going to do this and that but delivering is the thing you see.

Let's hope there will never be a manned FH. This would mean that BFR stays on target.

SLS is going to deliver.

Once or twice.
That would be once or twice more than a BFR will ever fly.
Ever? How much are you willing to bet, and what odds would you accept? :)
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Offline su27k

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Re: The fate of SLS after Falcon Heavy debut
« Reply #197 on: 02/14/2018 02:59 pm »
The "more than double the payload capacity" version of SLS is Block 2, which wouldn't be ready until 2028 at the earliest. SLS Block 1B has less than double the payload capacity, it wouldn't be ready until 2023 (i.e. 5 years from now). What is flying in 2020 is the SLS Block 1 which is 70t to LEO, about 6t more capable than FH, and just for this 6 extra tons you're willing to pay $7 billion?
The SLS is designed to put humans back into space. Deep space. A new opening of human space exploration. That's what it is designed for.

The Falcon Heavy is not going to carry people. Never, ever. Just satellites to LEO. That's what it is designed for.

You want to go to Mars, the Moon, or an Asteroid, with people? Then you're going on a SLS, or you're not going.

Apples and oranges.

No, SLS is going nowhere since there's no money for it, NASA's own life cycle cost analysis shows if you go to 130t SLS Block 2, there's very little money left for anything else. To quote https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20170008892.pdf:

Quote
Taking the Baseline Scenario forward, adding an Advanced Booster as in Figure 10, reveals how costs and ambitions increasing at a pace faster than budgets easily places a lien on 100% of any funding the end of the ISS might make available one day. This is just for the two launches per year, plus a replacement booster development in parallel, not payloads, not Mars or any mission in-space elements like habitation or landers.

Offline AncientU

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Re: The fate of SLS after Falcon Heavy debut
« Reply #198 on: 02/14/2018 03:14 pm »
That little 'bump' for two flights per year is $3B annually...

Quote
The SLS rocket was originally supposed to launch in 2017, but now the maiden flight of the SLS booster has slipped to 2020. That is understandable; most large aerospace rockets experience delays. However, the cost of a three-year delay is $7.8 billion.

This is for the Block 1 vehicle which will fly once.  The first Block 1B vehicle will follow by around three years.  The 130ton version may happen in 2028-2030, if someone finds a plus-up of $3B annually.

Quote
That $7.8 billion equates to 86 launches of the reusable Falcon Heavy or 52 of the expendable version. This provides up to 3,000 tons of lift—the equivalent of eight International Space Stations or one heck of a Moon base.

Quote
"The question is really, why would the government continue to spend billions of dollars a year of taxpayer money for a rocket that will be unnecessary and obsolete?" Lori Garver, a deputy administrator of NASA from 2009 to 2013, told Ars. "If the US continues this travesty, it will siphon off even more funds NASA could otherwise use for science missions, transfer vehicles, or landers that actually get us somewhere."
emphasis mine

https://arstechnica.com/science/2018/02/three-years-of-sls-development-could-buy-86-falcon-heavy-launches/
« Last Edit: 02/14/2018 03:20 pm by AncientU »
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Offline envy887

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Re: The fate of SLS after Falcon Heavy debut
« Reply #199 on: 02/14/2018 03:34 pm »
FH can put 34 tonnes to TMI with one crewed launch, the same mass as SLS. It only requires one additional uncrewed launch, which adds basically no risk to the crew.
The assumption in all of these discussions seems to be that the cost of developing the capability for a LEO rendezvous mission, cryogenic orbital refueling etc., is free.  It certainly is not. 

For example, you forgot to include here the extra two or three or more launches needed to refuel the trans-Mars stage in low earth orbit - assuming all are expendable launches.  If the stages are recovered, count on six or more refueling launches. 

 - Ed Kyle

Cryogenic refueling should absolutely be developed. (It would only take a total of 2 fully expendable, 3 partially expendable, or 4 fully recoverable FH to launch ~34 t to TMI)

But it isn't absolutely required. FH can get 33.6 t to TMI with 2 expendable launches in 16.8 t chunks with post-TMI rendezvous.

Or if you have two mismatched payloads, launch the heavy one (e.g. loaded deep space hab, ~22 t) to elliptical Earth orbit using all its fuel, then the light one (e.g. Crew Dragon, ~11.5 t) to rendezvous in EEO and use the remaining propellant in the crew launch vehicle to complete the remaining 1.5 km/s or so to TMI.

Or if you have one monolithic 33.6 t payload like a fueled MAV then launch 2 fully expendable FH to LEO and rendezvous, and burn the remaining propellant in one upperstage, discard it, flip around, and burn the rest of the propellant. Yes, the docking adapter has to take ~30 tonnes-force of axial load, but this would be uncrewed so there's no odd g-loads on the crew.

There are lots of options if you think outside the single launch per payload box.

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