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#1540 by woods170 on 19 Jun, 2020 07:53
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Another fine example is the very shape of the outer mold line of Orion and Starliner. Geometrically they are identical to the shape of Apollo CM. Never mind that there is a more volumetrically efficient shape for almost the same mass (bell shape such as used by Soyuz and Crew Dragon).
I can understand this argument for Starliner as it's a LEO capsule, but isn't part of the argument for Orion to have such a shape that it allows higher lift to reduce peak g loads during high energy reentries? The side walls being further from the plasma sheath produced by the primary heat shield?
That argument is effectively nullified by the Zond skip re-entries when those returned from their slingshots around the Moon. The Zond capsules have the exact same bell shape as the Soyuz capsules. Yet Zond still performed successful skip re-entry from lunar return velocities. Primary objective of the skip-reentry was to reduce peak G loads. Remember: Zond was to eventually send Soviet cosmonauts around the Moon. And those didn't like high G loads any better than their US counterparts. -
#1541 by woods170 on 19 Jun, 2020 08:41
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My point here, to be explicit, is not that Starliner is a good design. But, whatever your opinion may be of Boeing, or Boeing Management, or Boeing designs, the reality is that Boeing engineers are good engineers. Those Boeing engineers are the ones who made all the design decisions around Starliner, and, right or wrong, they reached the decision that they did for a reason, and only after many hours spent studying the alternatives. We shouldn't just dismiss this work off-hand as:
... a basic unwillingness to implement new ways of doing things.
Respectfully I disagree. Without the willingess to implement new ways of doing things there won't be progress. Starliner is, technologically speaking, a spacecraft mostly from the late 1990s, not the 2010s. Even the approach the Starliner team took to test the on-board software is 20 years out of date. As proven by the spectaculair failure of the flight software on OFT-1. -
#1542 by woods170 on 19 Jun, 2020 09:06
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Starliner design is sound and innovative, they use pusher LAS/SM, airbags for land landing. Landing on land makes refurbishing easier and gives quicker access to crew and cargo.
Testing is where Boeing has dropped ball especially in regards to SW.
If Starliner can keep its 7 seats for commercial launches maybe competitive with Dragon which has been forced to go with 4 seats. Those extra 3 seats mean their missions costs can be twice SpaceX and still charge same per seat. I'm assuming one seat for crew.
Unfortunately pusher LAS and airbags for land landing are not proof of Starliner being innovative.
Airbags for land landing was developed by NASA, originally for Orion. When NASA ditched it (pun intended) Boeing realized that the essential development work had already been done, free of charge, by NASA. In other words: Boeing was being cheap by applying something that, at that time, was absolutely no longer new, no longer innovative and, most important to Boeing, didn't cost a helluvalot to develop.
Something similar for pusher LAS. Boeing realized that adding a traditional tractor LAS to Starliner would require a boost protective cover. Both items (LAS and BPC) add substantial mass and are discarded during ascent. It would require launching Starliner on a more powerful (and very much more expensive) version of Atlas V.
Boeing also noticed that NASA had the fully developed RS-88 engine sitting around, almost free of charge, after the demise of Bantam.
So, again, Boeing took NASA developed technology to do a pusher LAS (which in itself had already been proven, again by NASA, via the MLAS demonstrator in 2009). Boeing didn't invent anything new. They were not innovative. They just applied what already was available, courtesy of US tax payer's dollars. So, also in this case, Boeing was being cheap.
And despite all this they are still the (way) more expensive of the two CCP providers. Hard to explain.
The two areas where Starliner actually is innovative is where Boeing managed to screw up: clamshell pressure vessel (it leaked more than expected during OFT-1 and needs improvements) and software for a fully autonomous spacecraft. And we all know how that software performed in flight. -
#1543 by ChrisWilson68 on 19 Jun, 2020 10:34
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And despite all this they are still the (way) more expensive of the two CCP providers. Hard to explain.
I think you mean hard to justify. It's not hard to explain why the more innovative approach can get more cost savings.
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#1544 by woods170 on 19 Jun, 2020 12:38
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And despite all this they are still the (way) more expensive of the two CCP providers. Hard to explain.
I think you mean hard to justify. It's not hard to explain why the more innovative approach can get more cost savings.
Yes, you are correct. Hard to justify.
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#1545 by freddo411 on 19 Jun, 2020 16:49
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Starliner design is sound and innovative, they use pusher LAS/SM, airbags for land landing. Landing on land makes refurbishing easier and gives quicker access to crew and cargo.
Testing is where Boeing has dropped ball especially in regards to SW.
If Starliner can keep its 7 seats for commercial launches maybe competitive with Dragon which has been forced to go with 4 seats. Those extra 3 seats mean their missions costs can be twice SpaceX and still charge same per seat. I'm assuming one seat for crew.
Unfortunately pusher LAS and airbags for land landing are not proof of Starliner being innovative.
Airbags for land landing was developed by NASA, originally for Orion. When NASA ditched it (pun intended) Boeing realized that the essential development work had already been done, free of charge, by NASA. In other words: Boeing was being cheap by applying something that, at that time, was absolutely no longer new, no longer innovative and, most important to Boeing, didn't cost a helluvalot to develop.
Something similar for pusher LAS. Boeing realized that adding a traditional tractor LAS to Starliner would require a boost protective cover. Both items (LAS and BPC) add substantial mass and are discarded during ascent. It would require launching Starliner on a more powerful (and very much more expensive) version of Atlas V.
Boeing also noticed that NASA had the fully developed RS-88 engine sitting around, almost free of charge, after the demise of Bantam.
So, again, Boeing took NASA developed technology to do a pusher LAS (which in itself had already been proven, again by NASA, via the MLAS demonstrator in 2009). Boeing didn't invent anything new. They were not innovative. They just applied what already was available, courtesy of US tax payer's dollars. So, also in this case, Boeing was being cheap.
And despite all this they are still the (way) more expensive of the two CCP providers. Hard to explain.
The two areas where Starliner actually is innovative is where Boeing managed to screw up: clamshell pressure vessel (it leaked more than expected during OFT-1 and needs improvements) and software for a fully autonomous spacecraft. And we all know how that software performed in flight.
Honest question:
Why a bolted clam shell capsule design? I'm certain the rest of the pressure vessel is both machined and welded out of smaller segments ... why not weld the top and bottom with the same FSW technique, or even manual welding. -
#1546 by arachnitect on 19 Jun, 2020 17:12
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Honest question:
Why a bolted clam shell capsule design?
Was supposed to make assembly easier. They wanted to do a lot of the work with the pressure vessel split. Bolt them together at the last minute.I'm certain the rest of the pressure vessel is both machined and welded out of smaller segments ... why not weld the top and bottom with the same FSW technique, or even manual welding.
They were trying to make the domes out of 1 piece of aluminum (spin formed, then machined).
edit if you look at these pictures you can get an idea of how the clamshell conops was supposed to work. Look how much equipment is installed before the domes are mated.
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#1547 by JEF_300 on 19 Jun, 2020 17:51
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The bolted together pressure vessel of Starliner doesn't get enough credit, I think. It's a really neat innovation.
It'd be a lot cooler 50 years ago when we were still expecting to build a new spacecraft for every flight, but the past is in the past and all that. -
#1548 by Jimmy_C on 19 Jun, 2020 20:19
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The bolted together pressure vessel of Starliner doesn't get enough credit, I think. It's a really neat innovation.
It'd be a lot cooler 50 years ago when we were still expecting to build a new spacecraft for every flight, but the past is in the past and all that.
Isn't Starliner CST-100 supposed too be reused? -
#1549 by Athelstane on 19 Jun, 2020 21:37
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The bolted together pressure vessel of Starliner doesn't get enough credit, I think. It's a really neat innovation.
It'd be a lot cooler 50 years ago when we were still expecting to build a new spacecraft for every flight, but the past is in the past and all that.
Isn't Starliner CST-100 supposed too be reused?
Well, part of it.
The service module, nose cone, and aeroshell are obviously discarded, but so too is the heat shield. -
#1550 by JEF_300 on 20 Jun, 2020 00:04
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The bolted together pressure vessel of Starliner doesn't get enough credit, I think. It's a really neat innovation.
It'd be a lot cooler 50 years ago when we were still expecting to build a new spacecraft for every flight, but the past is in the past and all that.
Isn't Starliner CST-100 supposed too be reused?
The main capsule is, yes, which is my point. If you plan on only building a few spacecraft and then reusing them, the fact that you made them easier to build becomes more of a marginal benefit. -
#1551 by erioladastra on 20 Jun, 2020 15:05
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The Boeing 777X will have a touchscreen display interface, replacing the cursor control devices featured in the original 777 and the 787. Starliner is a throwback even by 1990s widebody airliner standards.The iPad electronic flight bag was love at first sight for pilots, and the touchscreen-ification of the cockpit became inevitable much quicker than most had anticipated.And another cockpit photo.
Almost certainly a setup pilots will generally be happier with. But I can't help but think that Crew Dragon's approach is going to be more like the way forward for 21st century spacecraft.
The reason Boeing - and Orion - went with those screen interfaces even though touch screens were available was because of concerns of how they would perform with gloves on especially under high-g vibrations.
I see that this myth is persistent.
Doubts that touch screens could be used with modified gloves under high-g loads were effectively put to rests even when the shuttle was still flying.
The fact that Orion and Starliner don't have touch screens has more to do with a basic unwillingness to implement new ways of doing things.
Another fine example is the very shape of the outer mold line of Orion and Starliner. Geometrically they are identical to the shape of Apollo CM. Never mind that there is a more volumetrically efficient shape for almost the same mass (bell shape such as used by Soyuz and Crew Dragon).
A third fine example is that Orion is using the same antiquated primary heat shield material that was used on the Apollo CM. When NASA made that choice they knew that there were more modern materials out there that could do the job just as fine, but were cheaper and more efficient to produce, as well as adding less mass to the spacecraft. But a basic fear of "this hasn't been done before on this scale" led them to spend a cr*pload of money on a completely outdated technology with unnecessary high mass penalties for the spacecraft.
Actually no. The NASA crew office fought hard against touch screens convinced they were unsafe. SpaceX had to push hard to demonstrate it was ok and until DM-2 launched there were many who said it was not safe.
Starliner outer mold line was chosen to be the same as Orion (and now it is actually slightly different) so they could leverage off the work and analysis NASA did on Orion. Now if you want to find fault in that design...
As to the Starliner heatshield - it is actually innovative and deviated from the Orion one. NASA, again, fought hard for Boeing to prove to them it was good. Took a lot of extra work and cost and then it performed better than design. -
#1552 by erioladastra on 20 Jun, 2020 15:06
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If Starliner can keep its 7 seats for commercial launches maybe competitive with Dragon which has been forced to go with 4 seats. Those extra 3 seats mean their missions costs can be twice SpaceX and still charge same per seat. I'm assuming one seat for crew.
I've been curious whether the NASA required seating configuration for Dragon can be readily modified by SpaceX for non-NASA private flights?
Not that they would really want to do that for something like the weeklong medium earth orbit mission they're looking at for 2022, given how cramped that would make things...but it might have value for Axiom flights, since the completed Axiom segment/station is supposed to be able to support up to 8 crew by itself on a sustained basis.
The requirement by NASA was to fly 1-4 astronauts. How the seats were arranged were not specified - up to the company. And any reconfiguration, or not, was up to the company. There was no requirement to adjust/change the seats. -
#1553 by erioladastra on 20 Jun, 2020 15:06
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...but but but. These vehicles are automated - there is nothing to really play with on the screens during launch or re-entry (in high-g) and if there is (something that needs manual control), Nasa/SpaceX took care of that with a couple of important buttons at the bottom of the touch screens. No real need to have everything old school.
Why couldn't Boeing? Again I suspect they went with what they were used to and comfortable with, rather than challenging and pushing the design.
Ok, see this is where you're losing me. Of course Boeing could have also chosen to use touch screens. I'm not arguing that they couldn't. What I'm saying is that their reasons for choosing not to use touch screens go beyond, 'we're not familiar with them'. There is a logic to it.
Nominal design requirements are autonomous. However, the vehicle is required to also have manual override capability and the crew to do anything needed to prevent a catastrophic hazard. Many contingency cases require the crew to interact. -
#1554 by woods170 on 20 Jun, 2020 20:56
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Actually no. The NASA crew office fought hard against touch screens convinced they were unsafe. SpaceX had to push hard to demonstrate it was ok and until DM-2 launched there were many who said it was not safe.
Yes, the NASA crew office was against it. But a lot of the astronauts themselves were NOT against it. Because contrary to the crew office management several astronauts had actually bothered to study the results of several tests done, even before SpaceX had to push hard. You'll have to remember that initial investigations into the use of touch screens for crew interfaces began as early as 2007. That's long before the first CCP contracts were awarded. Courtesy of a little-known side-study ordered by NASA. Those tests clearly showed that the crew office's worries were ill-founded from the get-go.
But this is not the first time, and it won't certainly be the last time, that NASA's crew office is wrong about certain things.Starliner outer mold line was chosen to be the same as Orion (and now it is actually slightly different) so they could leverage off the work and analysis NASA did on Orion. Now if you want to find fault in that design...
Starliner's outer mold line is not identical to that of Orion, nor is it identical to that of the Apollo CSM. Starliner is however geometrically nearly identical to the Apollo CM. Orion's geometric shape is a direct copy of that op the Apollo CSM. It'w why NASA chose to go with that shape for Orion in the first place: NASA already had a huge amount of data on how that geometric form interfaces with the environments it travels thru. So, for Orion it meant a very much reduced development effort with regards to the geometric shape of Orion. And Boeing being Boeing they went with the same shape because that would be the cheaper option, courtesy of the work done by NASA on that shape in the 1960s and 2010s. Never mind you need to add 0.6 meters to the diameter (which translates into mass) to meet NASA's interior volume requirement.As to the Starliner heatshield - it is actually innovative and deviated from the Orion one. NASA, again, fought hard for Boeing to prove to them it was good. Took a lot of extra work and cost and then it performed better than design.
My point was about Orion's heat shield. But I'll admit that Starliner's BLA is a fine piece of work. But you failed to inform the rest of us that BLA is actually heavily based on work done earlier by NASA. BLA is no more special than is PICA-X, which was based on NASA's PICA development. So, is BLA innovative? IMO not to the extent you are trying to make me believe. -
#1555 by LouScheffer on 21 Jun, 2020 00:18
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Starliner is however geometrically nearly identical to the Apollo CM. Orion's geometric shape is a direct copy of that op the Apollo CSM. It'w why NASA chose to go with that shape for Orion in the first place: NASA already had a huge amount of data on how that geometric form interfaces with the environments it travels thru.
If you really want to see this process in action, check out Mars landers. As far as I know, every Mars lander ever has used the exact same shape during re-entry as the Viking landers, differing only in size. Mars is already hard enough, so no-one is willing to risk a decade of development, a $100M launch, and a 9 month trip, for the benefit of a shape that might be somewhat improved. Better to pick a shape that is known to work, and live with the packaging constraints. Given the consequences of potential failure of a new design, I can't say I blame them.
EDIT: specify this is just for re-entry. After they discard the shell and heatshield, they all look different. -
#1556 by Steven Pietrobon on 21 Jun, 2020 05:58
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My point was about Orion's heat shield. But I'll admit that Starliner's BLA is a fine piece of work. But you failed to inform the rest of us that BLA is actually heavily based on work done earlier by NASA. BLA is no more special than is PICA-X, which was based on NASA's PICA development. So, is BLA innovative? IMO not to the extent you are trying to make me believe.
For those people like me who don't know what BLA stands for, it is Boeing Lightweight Ablator. Couldn't find out much about it. Here are a couple of papers that refer to it, but don't give any information on what it is.
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#1557 by daedalus1 on 21 Jun, 2020 06:19
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My point was about Orion's heat shield. But I'll admit that Starliner's BLA is a fine piece of work. But you failed to inform the rest of us that BLA is actually heavily based on work done earlier by NASA. BLA is no more special than is PICA-X, which was based on NASA's PICA development. So, is BLA innovative? IMO not to the extent you are trying to make me believe.
For those people like me who don't know what BLA stands for, it is Boeing Lightweight Ablator. Couldn't find out much about it. Here are a couple of papers that refer to it, but don't give any information on what it is.
It's good writing practice to always write an acronym in full when first used. Don't assume people know what you know. -
#1558 by woods170 on 21 Jun, 2020 20:33
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My point was about Orion's heat shield. But I'll admit that Starliner's BLA is a fine piece of work. But you failed to inform the rest of us that BLA is actually heavily based on work done earlier by NASA. BLA is no more special than is PICA-X, which was based on NASA's PICA development. So, is BLA innovative? IMO not to the extent you are trying to make me believe.
For those people like me who don't know what BLA stands for, it is Boeing Lightweight Ablator. Couldn't find out much about it. Here are a couple of papers that refer to it, but don't give any information on what it is.
It's good writing practice to always write an acronym in full when first used. Don't assume people know what you know.
Absolutely. Good reminder. I sometimes forget that not everyone here is at the same level of familiarity with this stuff. -
#1559 by woods170 on 21 Jun, 2020 20:36
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Starliner is however geometrically nearly identical to the Apollo CM. Orion's geometric shape is a direct copy of that op the Apollo CSM. It'w why NASA chose to go with that shape for Orion in the first place: NASA already had a huge amount of data on how that geometric form interfaces with the environments it travels thru.
If you really want to see this process in action, check out Mars landers. As far as I know, every Mars lander ever has used the exact same shape as the Viking landers, differing only in size. Mars is already hard enough, so no-one is willing to risk a decade of development, a $100M launch, and a 9 month trip, for the benefit of a shape that might be somewhat improved. Better to pick a shape that is known to work, and live with the packaging constraints. Given the consequences of potential failure of a new design, I can't say I blame them.
For clarity: you are referring to the aeroshell of the landers.