Author Topic: NASA Launch Services Program outlines the alternative launcher review for EM-1  (Read 28339 times)

Offline Chris Bergin

Support NSF via L2 -- Help improve NSF -- Site Rules/Feedback/Updates
**Not a L2 member? Whitelist this forum in your adblocker to support the site and ensure full functionality.**

Offline Tim S

  • Full Member
  • ****
  • Posts: 583
  • MSFC
  • Liked: 878
  • Likes Given: 22
Great article! Might be hard for SpaceX fans to stomach, but it shows how deep this study went.

Offline Rocket Science

  • Senior Member
  • *****
  • Posts: 10586
  • NASA Educator Astronaut Candidate Applicant 2002
  • Liked: 4549
  • Likes Given: 13523
Meaty article Philip, thank you! :)
"The laws of physics are unforgiving"
~Rob: Physics instructor, Aviator

Online Coastal Ron

  • Senior Member
  • *****
  • Posts: 9108
  • I live... along the coast
  • Liked: 10485
  • Likes Given: 12181
Yes, not the ending SpaceX fans may have wanted to hear, but oh my gosh, what a story!

Wonderful writing job by Philip Sloss, and I must say that the NASA Launch Services Program (LSP) looks like a VERY smart group, and they did a very detailed analysis.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline GWH

  • Full Member
  • ****
  • Posts: 1746
  • Canada
  • Liked: 1936
  • Likes Given: 1278
Great article!

I don't think most SpaceX fans with a little background knowledge would have expected any different, it was well understood by most that FH isn't quite enough rocket for Orion.

I will however take offence with that lead image.... who did the scaling on that thing   :o
The tip of FH should be part way up the tapered payload adapter...
« Last Edit: 04/19/2019 10:08 pm by GWH »

Offline Lars-J

  • Senior Member
  • *****
  • Posts: 6809
  • California
  • Liked: 8488
  • Likes Given: 5390
Not a shocking conclusion... But that's what you get, when you try to take a spacecraft that has basically been designed purposefully for over a decade to NOT work with any commercial providers and then you try to answer the question "can we launch this on a commercial rocket anyway?"

The bit about the LAS rings very false, though. So they considered launching with a LAS, or with Orion inside a regular fairing. Uh... Did no one consider the obvious option? (see image - Orion ogive fairing without LAS)

And if we only had the technology breakthrough to launch a capsule without a fairing... ::) (CST-100, Dragon)
« Last Edit: 04/19/2019 10:40 pm by Lars-J »

Offline Khadgars

  • Full Member
  • ****
  • Posts: 1751
  • Orange County, California
  • Liked: 1133
  • Likes Given: 3164
Not a shocking conclusion... But that's what you get, when you try to take a spacecraft that has basically been designed purposefully for over a decade to NOT work with any commercial providers and then you try to answer the question "can we launch this on a commercial rocket anyway?"

The bit about the LAS rings very false, though. So they considered launching with a LAS, or with Orion inside a regular fairing. Uh... Did no one consider the obvious option? (see image - Orion ogive fairing without LAS)

And if we only had the technology breakthrough to launch a capsule without a fairing... ::) (CST-100, Dragon)

So you're saying your expertise single handily is superior to the entire team that considered all the options outlined in this three page article?

From the article, they considered as many options as they could.
Evil triumphs when good men do nothing - Thomas Jefferson

Offline Lars-J

  • Senior Member
  • *****
  • Posts: 6809
  • California
  • Liked: 8488
  • Likes Given: 5390
Not a shocking conclusion... But that's what you get, when you try to take a spacecraft that has basically been designed purposefully for over a decade to NOT work with any commercial providers and then you try to answer the question "can we launch this on a commercial rocket anyway?"

The bit about the LAS rings very false, though. So they considered launching with a LAS, or with Orion inside a regular fairing. Uh... Did no one consider the obvious option? (see image - Orion ogive fairing without LAS)

And if we only had the technology breakthrough to launch a capsule without a fairing... ::) (CST-100, Dragon)

So you're saying your expertise single handily is superior to the entire team that considered all the options outlined in this three page article?

From the article, they considered as many options as they could.

I'm not saying that at all. Just pointing out that if the only options they considered was A) the full LAS and B) inside a regular fairing, they missed some rather obvious choices and thus did a bad job. Or perhaps the article failed to list those alternatives.

Sometimes there are 'real' open studies, and sometimes there are rubber-stamping studies where the outcome was known in advance. This seems to fall in the latter category, from what I can tell in the article.

Offline Markstark

  • Full Member
  • ***
  • Posts: 351
  • Liked: 457
  • Likes Given: 83
The LAS has three motors. The attitude control motor, abort motor and jettison motor. The jettison motor allows the LAS tower to pull away the ogive fairings safely. You get rid of the LAS tower = you get rid of the ogive jettison capability. Sure you can come up with another way to jettison the ogives but I just wanted to explain how the current design works

p.s. excellent article Philip and great work by the LSP team.
« Last Edit: 04/19/2019 11:58 pm by Markstark »

Offline DaveS

  • Shuttle program observer
  • Senior Member
  • *****
  • Posts: 8575
  • Sweden
  • Liked: 1292
  • Likes Given: 67
The LAS has three motors. The attitude control motor, abort motor and jettison motor. The jettison motor allows the LAS tower to pull away the ogive fairings safely. You get rid of the LAS tower = you get rid of the ogive jettison capability. Sure you can come up with another way to jettison the ogives but I just wanted to explain how the current design works

p.s. excellent article Philip and great work by the LSP team.
Precisely. There's no interface to explosively jettison the ogive panels. They're bolted together and rely on the LAS jettison motor to pull the entire LAS assembly away, very much like the old Apollo LES, where if I am not mistaken the Boost Protective Cover (BPC) was one entire structure unlike the Orion BPC which is made up of four separate panels that are bolted together. The actual LAS tower is mated first to the Forward Bay Cover (FBC) of Orion, then the ogive assembly is mated to the LAS tower.
"For Sardines, space is no problem!"
-1996 Astronaut class slogan

"We're rolling in the wrong direction but for the right reasons"
-USA engineer about the rollback of Discovery prior to the STS-114 Return To Flight mission

Offline Lars-J

  • Senior Member
  • *****
  • Posts: 6809
  • California
  • Liked: 8488
  • Likes Given: 5390
The LAS has three motors. The attitude control motor, abort motor and jettison motor. The jettison motor allows the LAS tower to pull away the ogive fairings safely. You get rid of the LAS tower = you get rid of the ogive jettison capability. Sure you can come up with another way to jettison the ogives but I just wanted to explain how the current design works

p.s. excellent article Philip and great work by the LSP team.
Precisely. There's no interface to explosively jettison the ogive panels. They're bolted together and rely on the LAS jettison motor to pull the entire LAS assembly away, very much like the old Apollo LES, where if I am not mistaken the Boost Protective Cover (BPC) was one entire structure unlike the Orion BPC which is made up of four separate panels that are bolted together. The actual LAS tower is mated first to the Forward Bay Cover (FBC) of Orion, then the ogive assembly is mated to the LAS tower.

There are ways around it, but that means that you have to be willing to consider the alternative(s). Developing a mini-fairing with that ogive shape to replace the BPC to sit on top of Orion as I described it should NOT take 18 months. Not if you found a competent and efficient contractor.

Look at that image again of the Orion LAS, the absurdity of it. This cannot be the only way it can be done, can it?
« Last Edit: 04/20/2019 01:06 am by Lars-J »

Offline jarmumd

  • Full Member
  • ****
  • Posts: 411
  • Liked: 177
  • Likes Given: 70

There are ways around it, but that means that you have to be willing to consider the alternative(s). Developing a mini-fairing with that ogive shape to replace the BPC to sit on top of Orion as I described it should NOT take 18 months. Not if you found a competent and efficient contractor.

Look at that image again of the Orion LAS, the absurdity of it. This cannot be the only way it can be done, can it?

It's not just that though.  Gust, buffet, STEL for a rocket are major loads / structural drivers.  The LAS is pretty well characterized at this point.  Putting a mini fairing is an immense aerodynamic change.  Not impossible, but also not trivial - especially in 18 mo.

Offline butters

  • Senior Member
  • *****
  • Posts: 2418
  • Liked: 1731
  • Likes Given: 615
Orion EM-1's lack of docking capability made it impossible to do this in any reasonable way. If Orion EM-1 could dock with a passive ring on a Falcon upper stage, then the NASA engineer quoted in this article wouldn't have spent so much time worrying about the heavy tractor LAS. That's only a bummer if you're limited to a single FH launch. It's obvious that dual-launch was rejected first, then came the futile mass-reduction studies.

If we want to declare "victory" by doing a lunar free return in 2020, we can do that -- with Dragon. Orion is joined at the hip to SLS, and it's hard to imagine either of them surviving the cancellation of the other.

Offline Steven Pietrobon

  • Member
  • Senior Member
  • *****
  • Posts: 39630
  • Adelaide, Australia
    • Steven Pietrobon's Space Archive
  • Liked: 33369
  • Likes Given: 9598
I will however take offence with that lead image.... who did the scaling on that thing   :o
The tip of FH should be part way up the tapered payload adapter...

Yes, the RSRMV boosters and Falcon boosters have the same diameter of 3.66 m. I measure RSRMV to be 30 pixels wide and Falcon to be 26 pixels wide, so FH should be about 15% bigger.

One way to solve the LAS mass issue is to delete the abort and attitude control motors, leaving only the jettison motor. That is a new configuration though, which would take time to implement and aerodynamically simulate.
Akin's Laws of Spacecraft Design #1:  Engineering is done with numbers.  Analysis without numbers is only an opinion.

Offline wholmeswa

  • Full Member
  • *
  • Posts: 106
  • Liked: 18
  • Likes Given: 149
Great article and an example of good reporting. Asked the right questions and reported the answers.

Cleared up a lot of the questions I had after hearing about EM-1 commercial options.

Offline theonlyspace

  • Full Member
  • ****
  • Posts: 566
  • Rocketeer
  • AEAI Space Center, USA
  • Liked: 157
  • Likes Given: 882
If I READ THE ARTICLE CORRECTLY it seems that the  Orion service module is under powered when compared to the  thrust power and the fuel load  it carried and all the ablitys that  the Apollo service module had

Offline darkenfast

  • Member
  • Full Member
  • ****
  • Posts: 1602
  • Liked: 1934
  • Likes Given: 9571
The Number One Rule of the politicians and senior bureaucrats involved here is quite simple: "Thou shalt NOT get between the pigs and their trough".  Boeing, the other contractors and their Government allies will milk this source of money through to the bitter end.  It's their trough.
Writer of Book and Lyrics for musicals "SCAR", "Cinderella!", and "Aladdin!". Retired Naval Security Group. "I think SCAR is a winner. Great score, [and] the writing is up there with the very best!"
-- Phil Henderson, Composer of the West End musical "The Far Pavilions".

Offline MATTBLAK

  • Elite Veteran & 'J.A.F.A'
  • Senior Member
  • *****
  • Posts: 5361
  • 'Space Cadets' Let us; UNITE!! (crickets chirping)
  • New Zealand
  • Liked: 2242
  • Likes Given: 3883
If I READ THE ARTICLE CORRECTLY it seems that the  Orion service module is under powered when compared to the  thrust power and the fuel load  it carried and all the ablitys that  the Apollo service module had
Apollo CSM's Service Module carried more than 18 metric tons of hypergolic propellants and had the SPS engine give a thrust of 91kns - more than 20,000 pounds. The Orion Service Module will be only carrying 9 metric tons of propellant and will be developing about one-third the thrust of the Apollo SPS engine. The Orion's engine - an adapted Shuttle OMS engine - is from the same family line as the SPS unit. They are both helium pressure-fed, hypergolic propulsion systems. Yet it could definitely be pointed out that the Orion's delta-v performance is inferior to the older Apollo system.

Without at least a 50% increase in Service Module propellants; Orion will never really be able to both get itself into and out of Lunar orbit :(
"Those who can't, Blog".   'Space Cadets' of the World - Let us UNITE!! (crickets chirping)

Offline TomH

  • Senior Member
  • *****
  • Posts: 3047
  • Vancouver, WA
  • Liked: 1998
  • Likes Given: 994
If I READ THE ARTICLE CORRECTLY it seems that the  Orion service module is under powered when compared to the  thrust power and the fuel load  it carried and all the ablitys that  the Apollo service module had

The architecture was designed differently. The Apollo SM had to provide the ΔV for the entire 4 component stack of the spacecraft (service module, command module, lunar descent module, lunar ascent module) to achieve LOI (Lunar Orbit Insertion), then also provide the ΔV for TEI (Trans-Earth Injection) of the command and service modules back to Earth.

As designed in CxP (Constellation Program), the Altair lander was to have an enormous descent stage with a high ISP upgraded RL-10 hydrolox engine. This one engine and its tankage would have provided the ΔV for LOI of the full stack, and then the ΔV for the landing. This would have given the landing much greater propellant efficiency than the hypergolic descent engine on Apollo. Altair's ascent engine was to be hypergolic, necessitated by its loiter time on the surface. The single task for the Orion main engine, then, would only have been to provide the ΔV for TEI of the Orion command and service modules.

Within the CxP, Ares I died, Ares V dwarfed into SLS, Altair died, and Orion survived. Any comparison and contrast of the service modules of Apollo and Orion are inherently nonequivocable due to the difference in mission architecture. They simply were not designed to do the same things.

Offline TomH

  • Senior Member
  • *****
  • Posts: 3047
  • Vancouver, WA
  • Liked: 1998
  • Likes Given: 994
Well, at least the fact that this study was made gives us permission to discuss pros and cons of SLS/Orion vs. SpaceX and other commercial entities, as well as the possible integration of components with each other. There was a time when such discussion would have been quickly deleted with warnings about discussing only SLS/Orion within SLS/Orion threads and Falcon/Dragon/ITS within SpaceX threads. There was a lot of concern by many not to upset the pork & gravy train to legacy manufacturers, or the delicate existential permission so tentatively granted to new space.

We are now well past that. SpaceX has been too successful for congressional committee chairmen to sabotage its existence. SLS/Orion is a sinking ship and this study nothing more than an exercise in desperation. The reality is that SLS/Orion is not taking anyone to Luna, much less Mars.

The solution to returning to Luna is simple. It also is obvious. Not to discuss it is silly. To prohibit and censor that discussion is just wrong. Everyone here knows that the most logical and economical solution is to put the albatross out of its misery and commit the resources toward assisting SS/Super Heavy first toward Lunar landing then toward Mars.

How about it, Chris? Isn't it time we stopped pretending that elephant is not in the room, and talk constructively about how such a change in approach can achieve realistic and affordable Lunar and Martian exploration?

Tags:
 

Advertisement NovaTech
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1