[New] Space Launch System / Orion Discussion Thread

[tater]

 

[kerbiloid]

A reality private show.

(They need.)

Challenges.

Kinda "lick the handle in the frost", but "Stick out the hand for three seconds".

Edited November 16, 2022 by kerbiloid

[mikegarrison]

Instead of making some sort of arbitrary definition of what is payload and what is propulsion and what is fuel and yada yada, I suggest doing what we do for airplanes and just going by the takeoff mass.

Edited November 16, 2022 by mikegarrison

[kerbiloid]

2 minutes ago, mikegarrison said:

what is payload

Four worst workers of year.

Edited November 16, 2022 by kerbiloid

[tater]

Just now, mikegarrison said:

Instead of making some sort of arbitrary definition of what is payload and what is propulsion and what is fuel and yada yada, I suggest doing what we do for airplanes and just going by the takeoff mass.

Of the whole stack?

The trouble is that most are expendable, so you could have a really inefficient vehicle massing more, and lifting less, and the mass doesn't tell you anything useful—except broad class like "super heavy."

Even just the total mass delivered to orbit would be fine—sure, the mass might include a core stage dry mass (plus any residuals), but it would be consistent.

[mikegarrison]

Just now, tater said:

Of the whole stack?

The trouble is that most are expendable, so you could have a really inefficient vehicle massing more, and lifting less, and the mass doesn't tell you anything useful—except broad class like "super heavy."

Even just the total mass delivered to orbit would be fine—sure, the mass might include a core stage dry mass (plus any residuals), but it would be consistent.

Yes, of the whole stack.

It works for ships. It works for airplanes.

Airplanes can be more or less efficient at the same takeoff mass. They can have different fuel fractions, different payloads, different ranges (even from mission to mission). But we still categorize them by maximum takeoff mass (weight) because that is an easy and useful way to categorize and compare them.

Broadly speaking, a heavier rocket at takeoff is going to be more capable. The thrust needed at takeoff is dependent on the takeoff mass. The facilities it can be launched from are dependent on the takeoff mass. It's a reasonable way to categorize flight vehicles, even though it can never tell the whole story about that vehicle.

[Beccab]

7 minutes ago, tater said:

Even just the total mass delivered to orbit would be fine—sure, the mass might include a core stage dry mass (plus any residuals), but it would be consistent.

Not really - for instance, the ET and S-II of respectively STS and Saturn V (not INT-21 due to budget shortfalls) were left just short of orbit and reentered before doing a complete trip around the world; however, the Long March 5 notoriously doesn't, which gives it an advantage for something that really shouldn't be one

[PakledHostage]

Forgive me, but was that not all a bit underwhelming? I was totally subscribed to the hype beforehand and I stayed up to watch it launch live ast night, but now as I reflect on it in the sober light of day, I can't help but wonder if it wouldn't be better to spend the money on a robotic mission elsewhere in the solar system? That rocket could easily send a large payload to Uranus and/or Neptune or a lander to a Jovian or Saturnian moon. Instead of groundbreaking planetary science (and amazing photos of places we've only seen from Voyager 2 as it whipped by), we get some grainy images of the inside of a capsule and over-exposed images of a gibbous Earth. So many robotic missions to the moon have provided much better photos. 

I mean sure, if this is the first step towards actually returning to the moon to stay for longer periods of time, then it is probably worthwhile... But the sceptic in me expects the program to be cancelled before we get that far.

What we're probably going to get out of all of this is an extended Apollo 8 type mission with some (in the words of Chuck Yeager) "spam in a can" along for the ride. In the face of limited budgets, I'd love to see these awesome rockets do some truly awesome science instead.

[Gargamel]

10 hours ago, darthgently said:

Everyday Astronaut got better tracking shots than NASA.  8k, beautiful stuff

The streamed broadcast was so bad (I was watching NASAspaceFlight, I assume they were just piggybacking the official stream), that I went to bed before MECO.    Really disappointed.    

[SunlitZelkova]

23 minutes ago, PakledHostage said:

Forgive me, but was that not all a bit underwhelming? I was totally subscribed to the hype beforehand and I stayed up to watch it launch live ast night, but now as I reflect on it in the sober light of day, I can't help but wonder if it wouldn't be better to spend the money on a robotic mission elsewhere in the solar system? That rocket could easily send a large payload to Uranus and/or Neptune or a lander to a Jovian or Saturnian moon. Instead of groundbreaking planetary science (and amazing photos of places we've only seen from Voyager 2 as it whipped by), we get some grainy images of the inside of a capsule and over-exposed images of a gibbous Earth. So many robotic missions to the moon have provided much better photos. 

I mean sure, if this is the first step towards actually returning to the moon to stay for longer periods of time, then it is probably worthwhile... But the sceptic in me expects the program to be cancelled before we get that far.

What we're probably going to get out of all of this is an extended Apollo 8 type mission with some (in the words of Chuck Yeager) "spam in a can" along for the ride. In the face of limited budgets, I'd love to see these awesome rockets do some truly awesome science instead.

I think you have to be able to appreciate and support human spaceflight to be in awe of it.

Unlike on Mars or the outer planets where a human presence would contribute scientifically, most of the science that can be done by humans on the Moon that relates to the Moon can be done by robots. The Moon is really only useful for studying how humans do on the Moon.

Humans will be deployed to the Moon in such a capacity* over this decade and the next that we probably could have done the lunar science in a series of robotic missions funded with the same amount of money used for Artemis, except on a slightly better timeline.

*That is, barely

[wumpus]

16 hours ago, Rutabaga22 said:

Is there ANY way SLS could be reusable? I know people constantly ask if it is reusable, but I want to know if it could.

The Senate has gone out of their way to make this as least reusable as possible.  Expend "reusable" RS-25s first and then start on specifically designed non-reusable RS-25s.  Also, rocket reuse has so far required many experiments that can only be done with actual boosters.  I'm pretty sure Spacex lost more boosters (check the blooper video) than the most optimistic SLS launch schedule has launches.  The only other comparison is Rocket Labs, which is 0-2 in recovery (their method is unlikely to work on something the size of SLS).

They are already "reusing" bits of existing shuttle hardware, at a cost that exceeds simply designing a new rocket.  I'd expect SLS project managers (at Boeing/NASA/Senate) to find a way to "reuse" a SLS in a way that costs more than a new build if at all possible (which more or less happened with the Shuttle.  But at least the Shuttle was driving the technology that we need today).

[tater]

Yeah, if it's about science, all things being equal (funding/manpower), robots win. Always. Every year robots get better, too, so their capability to do the tasks we might want improves.

Human spaceflight is not about that.

 

[sevenperforce]

45 minutes ago, mikegarrison said:

Airplanes can be more or less efficient at the same takeoff mass. They can have different fuel fractions, different payloads, different ranges (even from mission to mission). But we still categorize them by maximum takeoff mass (weight) because that is an easy and useful way to categorize and compare them.

Broadly speaking, a heavier rocket at takeoff is going to be more capable. The thrust needed at takeoff is dependent on the takeoff mass. The facilities it can be launched from are dependent on the takeoff mass. It's a reasonable way to categorize flight vehicles, even though it can never tell the whole story about that vehicle.

Concur.

Intended orbit, ascent profile, recovery options…all of these things introduce too much uncertainty. The easiest way is to use total liftoff thrust. That, at least, is consistent.

I suppose an argument could be made that total liftoff power is more descriptive than total liftoff thrust. SLS has more thrust than Energia but Energia had more power. And we use power to describe vehicles often. 

[darthgently]

Given the image issue Artemis has suffered I am a bit confused why there wasn't a team specifically tasked with getting more rocket mounted in-flight video coverage to match the bar SpaceX has set.  To see the animated graphics in 2022 made it look goofy. 

It would have been money well spent, and honestly, could probably have been completely funded by leasing camera/radio space to private parties with a content sharing agreement with NASA 

[mikegarrison]

49 minutes ago, PakledHostage said:

Forgive me, but was that not all a bit underwhelming? I was totally subscribed to the hype beforehand and I stayed up to watch it launch live ast night, but now as I reflect on it in the sober light of day, I can't help but wonder if it wouldn't be better to spend the money on a robotic mission elsewhere in the solar system?

Welcome to the last 60 years of conflict between the people who want crewed space flight and the people who want uncrewed science probes.

[adsii1970]

1 hour ago, wumpus said:

The Senate has gone out of their way to make this as least reusable as possible. 

This statement deserves the understatement of the year. The United States, as well as many of the other Western nations, lack visionary leaders such as JFK, who saw the need for space exploration beyond the politics and policies of the Cold War era. Right now, there's very little interest by any Western politician in space flight or space exploration other than to keep restraint on the commercial development of human spaceflight and to do enough to keep one step ahead of political rivals, such as Russia (the old Soviet rival) and China, a nation that has plans for an ambitious space program not fully recognized by the West nor does the West recognize its full potential. (I will not elaborate further since I do not want to run afoul of forum guidelines).

1 hour ago, wumpus said:

I'm pretty sure Spacex lost more boosters (check the blooper video) than the most optimistic SLS launch schedule has launches.

Yes, it did. But this is a good thing. Each failure teaches us what does not work. SpaceX learned a lot from each failure. NASA learned (or hopefully learned) a lot from each scrubbed launch. But NASA is a government entity and it's budget is a function of government. Unfortunately, no government agency ever learns from its failures - or so it seems. Let's be optimistic and hope NASA has learned something from each of its previous failures.

On a separate thing, it is a shame we could not see more cooperation or sharing of data internationally and among even the private sector space corporations. In the ideal world, and I stress - ideal world - this would happen so each entity would not bog itself down repeating the same mistakes others have already done. If there were more cooperation - and if there had been more international/inter-corporational cooperation since the 1950s, imagine how much further humankind could be in our efforts to colonize and explore space. Maybe some of the 1960s and 1970s science fiction would actually be science-reality.

1 hour ago, SunlitZelkova said:

think you have to be able to appreciate and support human spaceflight to be in awe of it.

I agree. And you also have to be able to imagine the future of human spaceflight. Without it as a passion, without being in awe of it, one becomes bored of it. As many times as I've flown on aircraft, never have I ever gotten bored with flight. Now that I cannot fly because of my migraines, I long for flight even more. C'est la vie. But even on the campuses I work, there are people who are more excited over a bagel with cream cheese than they are over spaceflight.

1 hour ago, darthgently said:

Given the image issue Artemis has suffered I am a bit confused why there wasn't a team specifically tasked with getting more rocket mounted in-flight video coverage to match the bar SpaceX has set. 

It's NASA - a government entity. Any government entity never thinks that far ahead. "We're the government. They'll get what we give 'em and be happy about it!" Sadly, they are not accustomed to being challenged by a private corporation such as SpaceX. But I bet that if there is enough outcry, Artemis II will have such a cam feature. Or at least we can hope.

[tater]

25 minutes ago, adsii1970 said:

It's NASA - a government entity. Any government entity never thinks that far ahead. "We're the government. They'll get what we give 'em and be happy about it!" Sadly, they are not accustomed to being challenged by a private corporation such as SpaceX. But I bet that if there is enough outcry, Artemis II will have such a cam feature. Or at least we can hope.

I think they know they are behind the 8 ball on streaming. Once in space the limitation right now is bandwidth, but they really need to up that for crew missions.

[darthgently]

25 minutes ago, adsii1970 said:

It's NASA - a government entity. Any government entity never thinks that far ahead. "We're the government. They'll get what we give 'em and be happy about it!" Sadly, they are not accustomed to being challenged by a private corporation such as SpaceX. But I bet that if there is enough outcry, Artemis II will have such a cam feature. Or at least we can hope.

If Artemis II doesn't have better video, all the way around the moon (recorded if not live during signal loss) then people need to get fired.  It really is inevitable given how badly space needs to be messaged well and how cheap it is to do this.  But mostly we have Apollo as a model.  Given what video/photog tech they had available a much better videography effort was done then

[adsii1970]

6 minutes ago, tater said:

I think they know they are behind the 8 ball on streaming. Once in space the limitation right now is bandwidth, but they really need to up that for crew missions.

Maybe they can ask Musk to borrow some of Starlink’s capacity. To be honest, I was posting it to be funny at first; however, the longer I think of it, he’s a space geek and might do it. 

[darthgently]

Just now, adsii1970 said:

Maybe they can ask Musk to borrow Some of Starlink’s capacity. To be honest, I was posting it to be funny at first; however, the longer I think of it, he’s a space geek and might do it. 

I thought of that, but not sure how well Starlink would work for signals coming from "above" and the frequency ranges really aren't as ideal for lunar distance (pretty sure on that last)

Starlink for launch and recovery could be good

[Pthigrivi]

I don't think it occurred to me what its going to look like to go back to the moon with just better cameras. 

[tater]

4 minutes ago, Pthigrivi said:

I don't think it occurred to me what its going to look like to go back to the moon with just better cameras. 

The Hasselblad 70mm EDC still (film) cameras they used were excellent, but yeah, real time video will be profoundly better.

I would expect extremely high res images, the question is what is the max they can stream at vs saving to storage and releasing after they get home (8k video for that presumably).

[Pthigrivi]

9 minutes ago, tater said:

The Hasselblad 70mm EDC still (film) cameras they used were excellent, but yeah, real time video will be profoundly better.

I would expect extremely high res images, the question is what is the max they can stream at vs saving to storage and releasing after they get home (8k video for that presumably).

True the stills are incredible. But yeah I just mean to watch live it'll be something else. 

[adsii1970]

45 minutes ago, darthgently said:

I thought of that, but not sure how well Starlink would work for signals coming from "above" and the frequency ranges really aren't as ideal for lunar distance (pretty sure on that last)

I wonder if a few of the satellites could be reoriented to face the Moon to act as relays...

Just a thought on an overworked, over-stressed, and under-compensated brain (yes, mine!)

[magnemoe]

3 hours ago, mikegarrison said:

Instead of making some sort of arbitrary definition of what is payload and what is propulsion and what is fuel and yada yada, I suggest doing what we do for airplanes and just going by the takeoff mass.

The shuttle is a bit different. If it was just launching an satellite the shuttle was just an very heavy upper stage. Building IIS or repairing Hubble the shuttle was part of the payload. A bit like an standard truck over one with an huge crane. 
Or how military cargo planes differs from civilian ones, the military has rear ramps who let you airdrop stuff and tend to be able to lower fuselage for easier roll on and off some even has front door. 
This adds weight but also flexibility.  Or how smaller container ships tend to have their own cranes for unloading. 

Still think an shuttle configured starship would make sense down the line, larger cargo hold who is unpressurized, smaller crew cabin because smaller crew, 10 is a lot and shorter missions than going to Mars. 
Multiple robotic arms, construction repair and recover missions from LEO to GEO and moon or L2.