Questions tagged [sls]
Space Launch System, the putative replacement for the Space Shuttle for future large missions.
84
questions
1
vote
0
answers
71
views
Does SLS reuse any actual shuttle flight hardware besides engines? [duplicate]
Will any SLS use flown (eg. SRB casings) or unflown (eg. ET tankage) hardware built for the shuttle program besides the engines (RIP)?
3
votes
2
answers
193
views
What would have happened if lightning struck the Orion LES instead of the umbilical tower?
Yesterday, a lightning struck the SLS' umbilical tower during a scrubbed wet dress rehearsal.
Is it normal for a lightning to strike the umbilical tower instead of the 3 lightning arresters around the ...
7
votes
2
answers
290
views
How can Artemis 1 take so much longer for Earth-Lunar transit than the Apollo missions did?
The Artemis I mission will take 8-14 days to get from Earth to the Moon. Apollo 11 only took 3 days. Similarly the return will be 9-19 days for Artemis I and just over 2 days for Apollo 11.
Why is the ...
6
votes
1
answer
175
views
What is the time sequence for SRB burn-out and separation?
I understand that SRBs cannot be throttled or shut down, they need to "burn out". Since they are often used in pairs, I assume there is a statistical spread in the burn duration of the two ...
14
votes
1
answer
1k
views
Black/White patterns on SLS boosters, fairings - Are these still roll patterns
The main purpose of the large black/white patterns on many of the early rockets was to make it easier to spot whether the rocket is rolling. The pattern on the Saturn V was changed to avoid picking up ...
5
votes
1
answer
183
views
Will the Artemis I SLS do a static fire on the pad following rollout?
Following the rollout for the Artemis I wet dress rehearsal, or the rollout for launch, will the core stage perform a static fire on the pad?
1
vote
0
answers
95
views
Are there any plans on replacing the shuttle-era RS-25D's during the Artemis III/IV missions?
The last two Artemis missions which use the shuttle-era RS-25D engines will fly in 2025 and 2026. Is there ever a possibility that, in the case that Aerojet Rocketdyne delivers their RS-25Es (or at ...
4
votes
1
answer
147
views
Why aren't ejectable engine blocks in use today?
Related to my previous question regarding expending the RS-25s. Why aren't engine blocks, especially those expensive RS-25s on the SLS, made ejectable from the fuel tank assembly and parachute to be ...
4
votes
1
answer
1k
views
Why isn't NASA planning on saving some of the RS-25Ds due to their historical significance?
A while ago, Scott Manley made a video about the Artemis program and how NASA will expend all its Block II RS-25D engines through the SLS's first four launches. Why isn't NASA planning on putting some ...
6
votes
1
answer
182
views
What hardware does SLS actually share with STS?
I was thinking about it for a while and realized I really don't know. I'm guessing it's:
The RS-25s
The SRB segments
SRB seals/joints
SRB nosecone assemblies +(avionics/separation motors/housings)?
...
5
votes
2
answers
168
views
Are there any currently studied or hypothesized crewed Mars missions that utilize the Space Launch System?
Space Launch System is finally beginning to see the light at the end of the tunnel. If everything goes smoothly (fingers crossed!), we should see the Artemis program kicked into full drive by the end ...
9
votes
2
answers
2k
views
What do the banana values mean in this tweeted plot of heavy lift vehicle capabilities?
@FreddieR's answer to What are the longest current rocket payload fairings, capable of carrying long space station sections? contains the following graphic. It's attributed to Ken Kirtland and I found ...
2
votes
1
answer
133
views
Could Four SRBs Be Stacked on SLS, Thereby Generating 17.9 Million LLBs Thrust at Liftoff
I'm not sure about the total thrust of SLS Block II (Crew Stack). So the math could be wrong. Since the Atlas 5 has a version where 4 SRBs are used, is this also possible for SLS?
6
votes
1
answer
315
views
RS-25E cost estimate but sentence confusing (approximately: help; maybe)?
So recently someone found out that the industry studies for SLS had been FOIAed by a site called government attic. While the other studies are interesting in their own right (check them out honestly), ...
4
votes
1
answer
138
views
What specific device failed, causing engine #4 in the Core Stage Green Run to report a Failure Identification?
(See this Q&A for context if needed: What is a "Major Component Failure" referred to in news reports about the unsuccessful Space Launch System core stage test firing?)
In the post-test ...
3
votes
0
answers
206
views
Likely explanation for the bottom of the SLS rocket being covered with reflective silver "muffler" tape?
NASA.gov's First Artemis Rocket Stage Moved onto NASA Barge Ahead of Green Run contains a high resolution image of the rocket. The bottom end of the rocket's cylindrical shape is closed flat and ...
25
votes
1
answer
3k
views
What is a "Major Component Failure" referred to in news reports about the unsuccessful Space Launch System core stage test firing?
In reporting about the unsuccessful green run of the SLS core stage, Ars Technica mentions
About 50 seconds into what was supposed to be an 8-minute test firing, the flight control center called out, ...
2
votes
1
answer
202
views
Why doesn't NASA just again build the Altair LM or a modified Apollo LM for the Artemis project?
The Altair lunar module was part of the wonderful Constellation program cancelled in 2010; just the Orion spacecraft has been retained which is to deliver a crew into lunar orbit. The new carrier ...
2
votes
2
answers
389
views
Why is the Orion spacecraft so big?
The Orion spacecraft which is to be used for the Artemis missions will be rated for 6 astronauts. Why so many? Given the "political" assignment is to put "a woman and another man to the ...
1
vote
2
answers
214
views
"NASA's Europa Clipper has been liberated from the Space Launch System" How would the "physics" of a Starship-based mission differ from SLS?
The Hill's NASA's Europa Clipper has been liberated from the Space Launch System is quite an illuminating read about the politics of space launch. However, I noticed that it also says:
Both the ...
6
votes
1
answer
219
views
Is there a G-force curve estimated for a SLS launch?
Has the G-force curve for the launch of Block 1, Block 1B, or Block 2 (crew and or cargo) Space Launch Systems been determined? If there is no published estimates for the curve, is the estimate of the ...
8
votes
1
answer
584
views
How many US states receive large amounts of money due to SLS?
That NASA is spread out over so many locations across the US is history and discussed elsewhere in this site. Briefly, Congress approves funding and the funding ends up in many, many of congress' ...
18
votes
6
answers
7k
views
Why does the government still fund SLS while SpaceX is cheaper and has the same capabilities if not better?
Due to SpaceX's recent advancements in now proven rocket tech, why does the government still fund (what some would argue to be bloated) cost-plus contracts with Boeing and Lockheed? Am I missing ...
7
votes
0
answers
73
views
Escape system of SLS vs Ares I
One of the criticism directed at the Ares I rocket was the danger during a launch termination of the solid-propellant 1st stage. As far as I understood it, a terminated Titan IV solid-propellant ...
3
votes
1
answer
311
views
Is SLS capable of launching the core stage into LEO?
After watching the Hazegrayart video If Rockets were Transparent I realized that I didn't really have a clear idea what the Space Launch System (SLS) is capable of doing.
Question: Is SLS capable of ...
16
votes
2
answers
2k
views
Why isn't the Delta IV Heavy ever used for crewed spaceflight?
In 2014 the Orion spacecraft was launched on top of the Delta IV Heavy for the first time. Why do they build another rocket, the SLS, instead of launching the Orion on the Delta also with humans on ...
3
votes
1
answer
323
views
Why is ESA developing the Vinci engine rather than buying RL10Bs?
The Vinci engine seems very very similar to the RL10B. Both are hydrolox expander-cycle engines with 465 s Isp and extendible nozzles with a ~250:1 expansion ratio. The biggest difference is that the ...
6
votes
0
answers
160
views
What are these wires on the side of the SLS core stage?
I was reading about the SLS core being moved for testing and I noticed something odd on the core stage. There's several lines on the stage, which in closer inspection are wires. It's not obvious what ...
13
votes
1
answer
416
views
Where are the lost RS-25D Block 2 engines?
There were 21 RS-25D Block 2 engines made. Two of them never flew. Three of them were lost with the Columbia disaster. 16 of them are tagged for SLS's use, including 14 previously flown, and the two ...
5
votes
1
answer
436
views
Did the shuttle SRBs have separation motors?
Looking at a NASA fact sheet about the SLS SRBs and I noticed it has at the bottom around the nozzle, separation motors.
Watching shuttle launches It looks to me like the SRBs continue to fire ...
7
votes
1
answer
1k
views
What is the status of the F-1B engine development?
In this article https://arstechnica.com/science/2013/04/new-f-1b-rocket-engine-upgrades-apollo-era-deisgn-with-1-8m-lbs-of-thrust/ and in several answers on this site a modernized F-1 engine is ...
4
votes
1
answer
142
views
Could the SSMEs of the SLS do retro burns?
The SLS will use the main engines of the space shuttle. Are these capable of retro-burns in the upper atmosphere like SpaceX’s Merlin engines?
More broadly, could the SLS’ main engines and ...
3
votes
2
answers
192
views
How does the economy of a direct launch (to the Moon) compare with two launches docking in orbit?
How much more efficient would it be to use a launcher big enough to go directly to the surface of the Moon like Apollo did, compared with using two launches with a lesser rocket, say one with the ...
6
votes
1
answer
478
views
Are the APUs on the SLS SRBs planned to be hydrazine powered?
I recently read that the Space Launch System core stage, which uses renamed / slightly reworked Space Shuttle Main Engines and therefore requires a hydraulic system to service said engines, will use ...
-2
votes
2
answers
549
views
Why doesn't NASA plan a manned Venus flyby first? [closed]
After America will have returned to the Moon, why won't NASA make a Venus flyby mission with the Orion/SLS before going on to manned flights to Mars?
They are planning crewed missions to Venus (...
3
votes
1
answer
1k
views
What exactly is a "Green Run test" for SLS that NASA is considering skipping?
The Ars Technica article Rocket Report: A new Delta 2, Blue Origin inks with NASA, a fiery Falcon Heavy says:
Boeing seeks to ship SLS core stage by the end of 2019. With a renewed emphasis from the ...
3
votes
0
answers
168
views
What is holding SLS back from launching?
I'm kind of confused on this point SLS has engines, a tank, side rocket boosters, a capsule, and seemingly all of the pieces. What is the major technical issue right now that is keeping SLS from ...
1
vote
2
answers
290
views
Why would an 8-minute burn result in a 6-month delay?
The Ars Technica article Vice President may tell NASA to accelerate lunar landings ends with:
And on Thursday, NASASpaceFlight.com reported that the agency is considering skipping a critical test ...
4
votes
0
answers
114
views
Can Delta Heavy launch a fully fueled upper stage with no payload attached?
There is right now talk of a potential dual launch mission to fulfill EM-1, where a Delta Heavy would launch a fully fueled upper stage to LEO, to there bet met with the Orion spacecraft, likely ...
5
votes
2
answers
1k
views
NASA's RS-25 Engines shut down time
As a follow up to my other question about RS-25's ramp-up time, I was wondering what would be the ramp-down times for the RS-25, i.e. what would be the time that takes to go from 100% thrust to 0% ...
5
votes
1
answer
293
views
NASA's RS-25 Engines
I am developing a FSX-based space flight simulator FSX SpacePort. I've been trying to get the detailed specs on NASA's RS-25 engine, namely, what were the ramp-up times for this engine? As in, how ...
6
votes
1
answer
371
views
Could the SLS reach orbit without solid rocket boosters?
Could the SLS block 1 reach orbit without solid rocket boosters, and if so, how much payload could it lift?
If it couldn't reach orbit in the block 1 config, could it do so with the Exploration ...
7
votes
1
answer
617
views
What are these discs on the Crawler-Transporter?
I've just watched this footage of SLS's Mobile Launcher Platform being rolled out to LC-39B for fitting tests.
On the front of the drive trucks are two rotating discs with red markings which are ...
2
votes
0
answers
197
views
What is the nature of the sextant tests on the ISS for Orion cis-lunar emergency navigation?
According to the NASA Johnson video Space to Ground: A Star to Steer By: 08/10/2018:
A tool that once helped sailors cross vast oceans for centuries is now being put to the test in space. The crew ...
2
votes
0
answers
93
views
What is the scheduled launch date history for SLS EM-1?
The Falcon Heavy was famous for being "6 months away" for around 6 years, seen in this chart. How has the SLS maiden launch schedule changed since its first proposed date?
P.S. If someone could ...
18
votes
2
answers
5k
views
Do the solid rocket boosters of the Shuttle and SLS have a self-destruct system and was it activated during the Challenger disaster?
Videos of the Challenger shuttle explosion show both solid boosters speeding on after the main tank detonated. Were they eventually self-destructed by the ground control, or why not, and why not ...
6
votes
2
answers
377
views
How much will Europa Clipper weigh?
I realize that NASA will have to change Europa Clipper's loadout based on whether they are launching on the SLS 1b or the Atlas 5 backup, but does anyone know what those two mission masses will be, ...
7
votes
1
answer
545
views
RS-25 Hot Fire Test
Yesterday, NASA Stennis successfully completed a hot fire test of Aerojet Rocketdyne RS-25 a.k.a SSME. It was noted in the webcast before the test started that they were testing the 'engine controller'...
12
votes
2
answers
1k
views
What does the software quality process for NASA's SLS look like?
What does the software quality process for NASA's SLS look like? What are the relevant standards that they have to comply to? Do they have to show that they are CMMI compliant, for example? I'm ...
9
votes
1
answer
576
views
Do Orion's solar panels have adjustable sweep?
In this video overview of NASA's proposed EM-1 mission, the solar panels on the Orion spacecraft are initially shown extending perpendicular to the spacecraft (at around 3:46).
Shortly after that, as ...