_Augustus_

NASA SLS/Orion/Payloads

Recommended Posts

7 hours ago, sevenperforce said:

For EM-1, we know FH expendable has a payload of 26.7 tonnes to GTO. If my math is right, TLI is only 460 m/s beyond GTO. That's within Orion's capabilities five times over. No sweat.

Same with EM-2, though they would either have to man-rate FH or send crew up on Dragon 2, which runs into pad issues.

Orion's whole point is to be able to dock with LOP-G. Well, first Altair, then DSG, and now LOP-G. Have they not even figured THAT out yet?

Or they can send crew first to ISS in Dragon 2 for few days? While Orion gets in orbit crew uses Dragon 2 to dock with Orion?

Share this post


Link to post
Share on other sites
4 minutes ago, Cassel said:

Or they can send crew first to ISS in Dragon 2 for few days? While Orion gets in orbit crew uses Dragon 2 to dock with Orion?

The issue here would be how long stage 2 endurance is. Currently they’ve only gone what, 6 hours between burns?

besides, if F9 is crew rated, and SLS could be crew rated literally on the first flight, why not call FH crew rated after an uncrewed test flight?

Hmm, what about the LES, that thing is huge.

Share this post


Link to post
Share on other sites

Could NASA give a SLS development to some other companies like SpaceX or ULA rather then developing it by themselves? Or give SpaceX/Boeing/whoever a task like "Develop a huge SLS-class lifter in 5 years" and be good to go? It just seems like SpaceX could do that with SLS money?

Share this post


Link to post
Share on other sites
50 minutes ago, NiL said:

Could NASA give a SLS development to some other companies like SpaceX or ULA rather then developing it by themselves? Or give SpaceX/Boeing/whoever a task like "Develop a huge SLS-class lifter in 5 years" and be good to go? It just seems like SpaceX could do that with SLS money?

That’s not how NASA rolls. They ordered the SLS, not an SLS-class booster.

Otherwise Energiya (the company) would have responded to their RFPs, even if in jest.

Share this post


Link to post
Share on other sites
3 minutes ago, DDE said:

They ordered the SLS, not an SLS-class booster.

Slight correction, the Congress ordered NASA to build SLS, from specific parts made by specific manufacturers (who have political power). I'm not sure if NASA had any say in this.

Share this post


Link to post
Share on other sites
Posted (edited)
2 minutes ago, sh1pman said:

Slight correction, the Congress ordered NASA to build SLS, from specific parts made by specific manufacturers (who have political power). I'm not sure if NASA had any say in this.

I cant imagine congressmen and congresswomen being aerospace engineerers.

"We should store ClF3 and RP1 together!"

Edited by Xd the great

Share this post


Link to post
Share on other sites
2 hours ago, tater said:

The issue here would be how long stage 2 endurance is. Currently they’ve only gone what, 6 hours between burns?

besides, if F9 is crew rated, and SLS could be crew rated literally on the first flight, why not call FH crew rated after an uncrewed test flight?

Hmm, what about the LES, that thing is huge.

Here's how you do EM-2 without man-rating FH.

  1. Send crew and Dragon 2 to ISS on Falcon 9. 
  2. Reconfig 39A for FH.
  3. Integrate Orion (with or without LES) to FH; roll to pad; test fire.
  4. Dragon 2 departs ISS with Orion crew for nominal parking orbit.
  5. Orion launches to nominal parking orbit on FH.
  6. Dragon 2 performs rendezvous and docking within 1-2 orbits; crew is transferred; Dragon 2 undocks.
  7. FH upper stage burns residuals for TLI.
  8. Dragon 2 deorbits without crew.

 

Share this post


Link to post
Share on other sites
16 minutes ago, sevenperforce said:

Here's how you do EM-2 without man-rating FH.

  1. Send crew and Dragon 2 to ISS on Falcon 9. 
  2. Reconfig 39A for FH.
  3. Integrate Orion (with or without LES) to FH; roll to pad; test fire.
  4. Dragon 2 departs ISS with Orion crew for nominal parking orbit.
  5. Orion launches to nominal parking orbit on FH.
  6. Dragon 2 performs rendezvous and docking within 1-2 orbits; crew is transferred; Dragon 2 undocks.
  7. FH upper stage burns residuals for TLI.
  8. Dragon 2 deorbits without crew.

 

ISS is on a pretty bad inclination for EM-2, though.

Share this post


Link to post
Share on other sites
16 minutes ago, Bill Phil said:

 ISS is on a pretty bad inclination for EM-2, though.

IIRC Dragon 2 is rated for at least 7 days of free flight, I'm not sure if that is enough, though.

Share this post


Link to post
Share on other sites
48 minutes ago, Bill Phil said:

ISS is on a pretty bad inclination for EM-2, though.

Are you sure? EM-2 needs to go over the Van Allen belts anyway, not through.

Share this post


Link to post
Share on other sites
12 minutes ago, sevenperforce said:

Are you sure? EM-2 needs to go over the Van Allen belts anyway, not through.

One issue is less launch windows. If it's supposed to fly by the Moon there would be less launch windows over a given span of time, and they'd likely be shorter windows at that. Since you're not coplanar (or rather since you're significantly out of plane) with the Moon the mission will only be possible when the vehicle is at either the ascending or descending node relative to the Moon's orbit and the Moon is in position to approach the point where the vehicle will be.

Considering those limitations the orbit is really impractical for EOR Moon missions in general. 

The ISS goes through a part of the Van Allen belts - specifically the South Atlantic Anomaly.

Share this post


Link to post
Share on other sites
4 hours ago, Xd the great said:

I cant imagine congressmen and congresswomen being aerospace engineerers.

"We should store ClF3 and RP1 together!"

Go look through some of the Shuttle bashing threads.  There were many, many ways to build a better spacecraft using 1970s technology, but I have yet to see a better proposal that met all of US government's "real" requirements that wasn't the produced Shuttle.

Note "real" requirements scare quote is necessary due to the wild claims about cadence and cost/launch and how badly they were missed.  Missing big requirements *after* huge costs have been sunk and the program is humming along and producing results that are seen on the evening news "NASA is putting astronauts back in space" is much easier than missing some specific requirement like "cross-range capability" or "return keyhole satellite" when you are still in the design phase.  Getting 195 flights out of the thing shows excellent management of Congress.

It isn't a public/private issue between "NASA can't build rockets and should let SpaceX/ULA/Blue Origin build them instead" it is that Congress can't help but micromanage NASA in ways that the commercial resupply/commercial crew contracts won't let them.  So NASA can only build rockets when Congress lets them, which is to say when pigs fly (or we are in the middle of a space race and NASA can say "No.  But fund us anyway.").  Generally speaking NASA's scientific programs are sufficiently low profile to avoid Congressional meddling, so that works out fine (JWST appears to be botched internally by NASA).

Share this post


Link to post
Share on other sites

On March 14, 2019, NASA Administrator Jim Bridenstine sent this message to NASA employees and contractors:

Yesterday, I was asked by Congress about the schedule slip of the Space Launch System and plans to get NASA back on track. I mentioned that we are exploring the possibility of launching Orion and the European Service Module to low-Earth orbit on an existing heavy-lift rocket, then using a boost from another existing vehicle for Trans Lunar Injection. Our goal would be to test Orion in lunar orbit in 2020 and free up the first SLS for the launch of habitation or other hardware in 2021. This would get us back on schedule for a crewed lunar orbital mission in 2022 with the added bonus of a lunar destination for our astronauts.

We are studying this approach to accelerate our lunar efforts. The review will take no longer than two weeks and the results will be made available. Please know that NASA is committed to building and flying the SLS for the following reasons:

  1. Launching two heavy-lift rockets to get Orion to the Moon is not optimum or sustainable.
  2. Docking crewed vehicles in Earth orbit to get to the Moon adds complexity and risk that is undesirable.
  3. SLS mitigates these challenges and allows crew and payloads to get to the Moon, and eventually to Mars, safer and more efficiently than any temporary solution used to get back on track.

I believe in the strength of our workforce and our ability to utilize every tool available to achieve our objectives. Our goal is to get to the Moon sustainably and on to Mars. With your focused efforts, and unmatched talent, the possibility of achieving this objective is real.

Ad astra,

Jim Bridenstine

Share this post


Link to post
Share on other sites
58 minutes ago, Ultimate Steve said:

On March 14, 2019, NASA Administrator Jim Bridenstine sent this message to NASA employees and contractors:

  1. Launching two heavy-lift rockets to get Orion to the Moon is not optimum or sustainable.

Other than being cheaper and safer than launching SLS.

58 minutes ago, Ultimate Steve said:
  1. Docking crewed vehicles in Earth orbit to get to the Moon adds complexity and risk that is undesirable.

As opposed to docking crewed vehicles in Earth orbit to get (in)to the ISS, which is routine.

58 minutes ago, Ultimate Steve said:
  1. SLS mitigates these challenges and allows crew and payloads to get to the Moon, and eventually to Mars, safer and more efficiently than any temporary solution used to get back on track.

Nothing says "efficiently" like launching less than once a year.

Share this post


Link to post
Share on other sites
2 hours ago, Ultimate Steve said:

On March 14, 2019, NASA Administrator Jim Bridenstine sent this message to NASA employees and contractors:

In no way does my like constitute condoning Bridenstine's message.

My interpretation of this is that they're willing to live with the hypocrisy of proving a better solution and claiming that the pork barrel is necessary.

In short: "Don't worry. We may be furious that you're so many years behind schedule and so many billions above your budget, and we do need to show progress... but do not worry for your jobs, the pork shall continue to flow. We don't give jobs based on antiquated concepts like merit, after all. We're just going to launch Re-Election Mission 1 and go back to wasting the American public's money."

Share this post


Link to post
Share on other sites

NASA is stuck with politics, forever. It’s an occupational hazard of spending other people’s money.

The program will continue until obviated by some commercial option that makes it look crappy.

Share this post


Link to post
Share on other sites
1 hour ago, tater said:

The program will continue until obviated by some commercial option that makes it look crappy.

Would it be practical to skip straight to Block 2, now that FH is a thing? FH can do EM- missions to NRHO (with a kick stage, no co-manifested cargo), Gateway can also be built and serviced with commercial heavy rockets. Only Block 1B can do things that commercials can’t (yet). Block 2 will be useful for things like heavy landers, base modules, pressurized rovers, etc. Of course, when Starship comes, there will be no sense in continuing SLS development. But until then it still makes a bit of sense.

Share this post


Link to post
Share on other sites

The current loss of the EUS is the real issue. An 8m rocket with no suitable US is a waste of time. Better as you suggest, go to block 2, and stop with the comanifested cargo nonsense. The original point (Constellation) was to entirely separate heavy lift from crew, and that was correct. 

Share this post


Link to post
Share on other sites
13 minutes ago, tater said:

The current loss of the EUS is the real issue. An 8m rocket with no suitable US is a waste of time. Better as you suggest, go to block 2, and stop with the comanifested cargo nonsense. The original point (Constellation) was to entirely separate heavy lift from crew, and that was correct. 

Yes, but we’re way past the point where that would yeild the expected benefit - namely, using RS-68s in the core.

They should have never man-rated the SLS.

Share this post


Link to post
Share on other sites
14 minutes ago, DDE said:

Yes, but we’re way past the point where that would yeild the expected benefit - namely, using RS-68s in the core.

They should have never man-rated the SLS.

This.

Share this post


Link to post
Share on other sites
2 hours ago, tater said:

This.

How to shock the laymen?

”This rocket is TOO safe”.

Share this post


Link to post
Share on other sites

So SLS/Orion starts as Constellation.

Constellation sensibly separates heavy (cargo) lift from crew—even if their crew LV idea was stupid (it was). Mission architectures were EOR types, possibly involving ISS. The EDS was a sort of disposable tug, but minus Shelby, could easily have become a tug. Regardless, Ares V puts 188 tonnes in LEO, a perfectly useful number.

Constellation gets cancelled, and replaced with SLS, which comanifests crew and cargo, for reasons that escape me. Architectures moved to LOR, but now stretches timelines (uselessly low cadence) to one such mission per year. Cargo to LEO? With comanifested payloads, cut 26+ tonnes off the top (what’s the LES mass).

Where are we now?

Talk of using another LV to loft Orion to LEO—which is entirely sensible. Using distributed launches, tugs, and propellant transfer. SLS moves to possibly cargo only. This would be good, but it still sucks compared to Ares V in capacity, and to make sense, it needs to be the full 8m Block 2, even then.

What a waste of 10 years since Constellation. (Even if you don’t like that program, it made far more sense)

 

Share this post


Link to post
Share on other sites
Posted (edited)
On 3/15/2019 at 6:42 AM, sh1pman said:

FH

Diameter of FH : 3.66 m.

Diameter of FH/F9 fairing : 5.2 m, height 13 m, roughly cylindrical.

Diameter of Orion CM : 5.02 m, height 3.3 m + LES, fully conical.

You're not going to get away with flying a pancake on top of a pencil.

Edited by YNM

Share this post


Link to post
Share on other sites
Spoiler
23 hours ago, DDE said:

How to shock the laymen?

”This rocket is TOO safe”.

An oversafe rocket with overqualified crew.

 

Share this post


Link to post
Share on other sites
3 hours ago, YNM said:

Diameter of FH : 3.66 m.

Diameter of FH/F9 fairing : 5.2 m, height 13 m, roughly cylindrical.

Diameter of Orion CM : 5.02 m, height 3.3 m + LES, fully conical.

You're not going to get away with flying a pancake on top of a pencil.

 

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.