Author Topic: SLS General Discussion Thread 2  (Read 209544 times)

Online Chris Bergin

SLS General Discussion Thread 2
« on: 07/13/2015 02:02 PM »
New Discussion Thread for SLS.

SLS Articles (lots of them):
http://www.nasaspaceflight.com/tag/sls/

L2 SLS:
http://forum.nasaspaceflight.com/index.php?board=48.0

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Do not post unless it's useful, on topic and interesting. This is not a place for the politics (that's in Space Policy), this is a place about the vehicle.

Online rayleighscatter

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Re: SLS General Discussion Thread 2
« Reply #1 on: 07/20/2015 09:55 PM »
A NASA rendering.

Offline russianhalo117

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Re: SLS General Discussion Thread 2
« Reply #2 on: 07/21/2015 12:05 AM »
A NASA rendering.

The ML shown above does not match the present design for the converted ML.

Offline Zed_Noir

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Re: SLS General Discussion Thread 2
« Reply #3 on: 07/21/2015 08:34 AM »
A NASA rendering.

The ML shown above does not match the present design for the converted ML.
Hope NASA is not thinking of modifying the current ML or possibly even build a new ML. :o Doesn't make much financial sense with the current launch rate of record.

Online the_other_Doug

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Re: SLS General Discussion Thread 2
« Reply #4 on: 07/21/2015 04:11 PM »
A NASA rendering.

The ML shown above does not match the present design for the converted ML.
Hope NASA is not thinking of modifying the current ML or possibly even build a new ML. :o Doesn't make much financial sense with the current launch rate of record.

Well, if they're going to use the ML for SLS, it has to be modified from STS configuration.  I'm assuming you're trying to push an anti-SLS point, here, saying the ML shouldn't be modified because you don't think the SLS should ever fly.  But since it is being built and will fly, your point is moot.  They have to have at least two SLS-configured mobile launchers, one for backup in case the other gets stuck on a glitched C-T, as happened early in the Apollo flow.
-Doug  (With my shield, not yet upon it)

Offline Jim

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Re: SLS General Discussion Thread 2
« Reply #5 on: 07/21/2015 04:15 PM »
Hope NASA is not thinking of modifying the current ML or possibly even build a new ML. :o Doesn't make much financial sense with the current launch rate of record.

Well, if they're going to use the ML for SLS, it has to be modified from STS configuration.  I'm assuming you're trying to push an anti-SLS point, here, saying the ML shouldn't be modified because you don't think the SLS should ever fly.  But since it is being built and will fly, your point is moot.  They have to have at least two SLS-configured mobile launchers, one for backup in case the other gets stuck on a glitched C-T, as happened early in the Apollo flow.

There is only one ML and it was built for Ares I and is being converted for SLS.  The three shuttle MLP's are not being used for anything.
« Last Edit: 07/21/2015 04:17 PM by Jim »

Online the_other_Doug

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Re: SLS General Discussion Thread 2
« Reply #6 on: 07/21/2015 04:22 PM »
Hope NASA is not thinking of modifying the current ML or possibly even build a new ML. :o Doesn't make much financial sense with the current launch rate of record.

Well, if they're going to use the ML for SLS, it has to be modified from STS configuration.  I'm assuming you're trying to push an anti-SLS point, here, saying the ML shouldn't be modified because you don't think the SLS should ever fly.  But since it is being built and will fly, your point is moot.  They have to have at least two SLS-configured mobile launchers, one for backup in case the other gets stuck on a glitched C-T, as happened early in the Apollo flow.

There is only one ML and it was built for Ares I and is being converted for SLS.  The three shuttle MLP's are not being used for anything.

Gotcha, thanks for the clarification.  Interesting, I would have thought that they would have used the MLPs as the basis for the new MLs, just as they used the Apollo MLs as the basis for the MLPs.  I'm also a little surprised they would only plan on having one of them, since as I say there was an Apollo ML that got stuck off to the side of 39A for several months when its C-T failed after a test drive of just the ML to the pad, and needed to be repaired in-place, back in 1968, IIRC.
-Doug  (With my shield, not yet upon it)

Offline darkenfast

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Re: SLS General Discussion Thread 2
« Reply #7 on: 07/22/2015 05:44 AM »
This rendering still has the phony "Saturn V" looking paint-job as well.  Somebody at NASA just won't let that one go away.

Offline Spacely

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Re: SLS General Discussion Thread 2
« Reply #8 on: 07/22/2015 04:19 PM »
How major were the modifications to turn the Ares I ML into one for SLS? Was it a total rebuild?

Online the_other_Doug

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Re: SLS General Discussion Thread 2
« Reply #9 on: 07/22/2015 06:56 PM »
When we speak of the Ares 1 ML, we aren't talking about the one they used to launch Ares 1X, are we?  I thought that was a standard Shuttle MLP and the Ares 1X was positioned over one of the SRB fire holes.

I'm taking it that there was an ML that was being constructed for Ares 1 that was mostly finished when the Ares program was canceled?  And this is what is being modified to support SLS?

Sorry if I wasn't following the construction of Areas program support structures all that closely in the mid-aughts.  Had other things that were pre-occupying me at the time...
-Doug  (With my shield, not yet upon it)

Offline Jim

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Re: SLS General Discussion Thread 2
« Reply #10 on: 07/22/2015 07:31 PM »

I'm taking it that there was an ML that was being constructed for Ares 1 that was mostly finished when the Ares program was canceled?  And this is what is being modified to support SLS?


Yes and yes.

Offline Star One

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Re: SLS General Discussion Thread 2
« Reply #11 on: 07/22/2015 08:24 PM »
NASA Developing Solar-sailing Cubesats for Inaugural SLS Launch

Quote
WASHINGTON ó NASA is developing a pair of solar-sailing, science-collecting cubesats that will hitch a ride on the Space Launch Systemís inaugural July 2018 launch.

The two spacecraft, currently envisioned as six-unit cubesats with deployable solar sails, will travel beyond low Earth orbit to conduct scientific observations of an asteroid and the moon.

NASAís Near Earth Asteroid Scout, or NEA Scout, cubesat will conduct a 2020 flyby of asteroid 1991 VG to determine its size, movement and chemical composition.

The aptly named Lunar Flashlight cubesat will sail into a polar orbit around the moon by early 2019 then use its solar sail as a mirror, reflecting sunlight onto the cold, dark regions of the lunar poles. Once the polar regions are illuminated, onboard sensors will help determine the composition and distribution of frozen water and other volatiles hidden in the moonís shadows.

http://spacenews.com/nasa-developing-solar-sailing-cubesats-for-inaugural-sls-launch/#sthash.0Ta4ceDh.dpuf
« Last Edit: 07/22/2015 08:26 PM by Star One »

Offline Vultur

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Re: SLS General Discussion Thread 2
« Reply #12 on: 08/10/2015 04:00 AM »
That will be the EM-1 launch, right? July 2018 is the current date for that?

Also, what's the current plan for the advanced boosters? I've read several different things and I'm not clear on which is right.

Offline Endeavour_01

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Re: SLS General Discussion Thread 2
« Reply #13 on: 08/10/2015 05:14 PM »
That will be the EM-1 launch, right? July 2018 is the current date for that?

Correct on both counts.

Quote
Also, what's the current plan for the advanced boosters? I've read several different things and I'm not clear on which is right.

Right now NASA is proceeding with SLS Block I for EM-1 (Core stage plus current boosters plus ICPS upper stage) and going immediately to Block IB (Core stage plus current boosters plus EUS upper stage). Advanced boosters will come after Block IB (so late 2020s). There are a couple of way NASA could go with this. They could go with Block II (Core stage plus advanced boosters plus another upper stage) or Block IIB (Core stage plus advanced boosters plus EUS upper stage).
I cheer for both NASA and commercial space. For SLS, Orion, Falcon 9, Falcon Heavy, Dragon, Starliner, Cygnus and all the rest!
I was blessed to see the launch of Space Shuttle Endeavour on STS-99. The launch was beyond amazing. My 8-year old mind was blown. I remember the noise and seeing the exhaust pour out of the shuttle as it lifted off. I remember staring and watching it soar while it was visible in the clear blue sky. It was one of the greatest moments of my life and I will never forget it.

Offline brickmack

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Re: SLS General Discussion Thread 2
« Reply #14 on: 08/11/2015 12:28 AM »
Quote
Also, what's the current plan for the advanced boosters? I've read several different things and I'm not clear on which is right.

Right now NASA is proceeding with SLS Block I for EM-1 (Core stage plus current boosters plus ICPS upper stage) and going immediately to Block IB (Core stage plus current boosters plus EUS upper stage). Advanced boosters will come after Block IB (so late 2020s). There are a couple of way NASA could go with this. They could go with Block II (Core stage plus advanced boosters plus another upper stage) or Block IIB (Core stage plus advanced boosters plus EUS upper stage).

Probably more like early-mid 2020s. Last I heard they've only got enough SRB parts leftover from the shuttle to make about 10 boosters (so 5 SLS flights). 1 pair would be used for EM 1, and the next flight would be in 2021 or maybe 2020 if we're lucky, at about 1 launch a year, so that puts 2025 as the latest they could do a launch before switching to advanced boosters, unless they restart production (not exactly cheap). They've got the equipment to fuel and stack them, but thats it

Offline Vultur

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Re: SLS General Discussion Thread 2
« Reply #15 on: 08/11/2015 01:17 AM »
Thank you.

That will be the EM-1 launch, right? July 2018 is the current date for that?

Correct on both counts.

Cool. Wikipedia says September 30 so that's why I was surprised.

Offline Endeavour_01

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Re: SLS General Discussion Thread 2
« Reply #16 on: 08/11/2015 08:48 PM »

Probably more like early-mid 2020s. Last I heard they've only got enough SRB parts leftover from the shuttle to make about 10 boosters (so 5 SLS flights). 1 pair would be used for EM 1, and the next flight would be in 2021 or maybe 2020 if we're lucky, at about 1 launch a year, so that puts 2025 as the latest they could do a launch before switching to advanced boosters, unless they restart production (not exactly cheap). They've got the equipment to fuel and stack them, but thats it

I was under the impression that it was 10 pairs of boosters. If not then you are correct.
I cheer for both NASA and commercial space. For SLS, Orion, Falcon 9, Falcon Heavy, Dragon, Starliner, Cygnus and all the rest!
I was blessed to see the launch of Space Shuttle Endeavour on STS-99. The launch was beyond amazing. My 8-year old mind was blown. I remember the noise and seeing the exhaust pour out of the shuttle as it lifted off. I remember staring and watching it soar while it was visible in the clear blue sky. It was one of the greatest moments of my life and I will never forget it.

Offline Raj2014

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Re: SLS General Discussion Thread 2
« Reply #17 on: 08/11/2015 09:29 PM »
Does anyone know the exact and accurate dimensions of the SLS block 1B? Has NASA discussed what they would do after EM-2? I know they have plans for ARM, Europa and then Mars but do they have plans before ARM of in between?  When will NASA use the USA? Has NASA thought of using aerospike engines for the core stage instead? I read that aerospike engines have had testing and are ideal for launches from the ground to LEO.

Offline Jim

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Re: SLS General Discussion Thread 2
« Reply #18 on: 08/12/2015 12:04 AM »
Has NASA thought of using aerospike engines for the core stage instead?

No, the whole point of the SLS design is to use derivatives of shuttle propulsion elements (SSME and SRB's).    SLS will fly only one to two times a year.  Not enough to justfiy a new engine development program.

These questions are the same as those on Orion.  SLS and Orion are not designed to push the state of the art or to reduce operational costs.

Offline Raj2014

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Re: SLS General Discussion Thread 2
« Reply #19 on: 08/12/2015 11:36 AM »
Has NASA thought of using aerospike engines for the core stage instead?

No, the whole point of the SLS design is to use derivatives of shuttle propulsion elements (SSME and SRB's).    SLS will fly only one to two times a year.  Not enough to justfiy a new engine development program.

These questions are the same as those on Orion.  SLS and Orion are not designed to push the state of the art or to reduce operational costs.

Interesting, I also read that during the use of the SLS it will be improved, is this true? Why not reduce operational costs? I understand with what you have said Jim, that they are re-using technologies but will that not reduce the costs as well?

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