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#160
by
TripleSeven
on 03 Aug, 2018 13:13
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With the shuttle, NASA used what they called "success-oriented management" https://go.nasa.gov/2OxYcwP. To reduce cost, they did not do thorough testing on all components but instead assembled them and tested the assembled unit as a whole. As the Challenger explosion demonstrated, operating outside previous test parameters with crew onboard is a bad idea. NASA was scarred by the loss of two crews (they use the term "scarred" in discussions with SpaceX) and as a result have become much more conservative about crew protection. Perhaps too conservative. Elon Musk has been clear that people will die as a result of Mars colonization. Hopefully, as few as possible.
Strangely enough although as I am told there were some pretty close calls..."success oriented management" worked with the shuttle
As you imply, No shuttle was ever lost due to a failure of a component ...like what caused the loss of the last Boeing on a test flight, the B29 that killed Eddie Allen and his crew when the engines caught on fire.
they were all lost by a failure of management and the need to operate the shuttle with a known component failure tree.
Pilots were on board the Triple 7 when on its maiden flight the engines both compressor stalled (which is the worst problem Boeing has had on the maiden test flight of a commercial airliner) and were responsible for the "fix"
NASA HSF has a well lets call it a "unique" view toward flight safety. In large manner it is because all the expertise to do it, retired a long time ago...and just a thought occurred here...with the stand down of human spaceflight for the last bunch of years...its unclear that any real expertise in operation of a crewed vehicle exist...
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#161
by
Alexphysics
on 03 Aug, 2018 13:18
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You may be talking about US crewed spacecraft capabilities since Soyuz spacecrafts can rendezvous and dock with the ISS autonomously while the crew checks the spacecraft systems and if something fails they can take over the control of the spacecraft. So it's all pretty much like Dragon 2 and Starliner.
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#162
by
marsbase
on 03 Aug, 2018 13:45
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As you imply, No shuttle was ever lost due to a failure of a component
Not at all. The Challenger was lost due to the failure of an O-ring component of the solid booster. It was being operated outside the tested range of acceptable temperatures. You are correct that this was also a management failure since NASA engineers told management the solid booster should not be flown at those untested temperatures.
Columbia was also lost due to a component failure, in that case the breakage of foam insulation on the shuttle fuel tank. I call it a failure since it was not designed to break in that way. This was a double management failure since the shuttle was allowed to launch with known faulty foam and NASA management ignored efforts to photograph the shuttle for damage.
NASA management could have prevented both tragedies by requiring testing and modification of those components or modification of launch conditions to match tested scenarios.
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#163
by
TripleSeven
on 03 Aug, 2018 13:59
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As you imply, No shuttle was ever lost due to a failure of a component
Not at all. The Challenger was lost due to the failure of an O-ring component of the solid booster. It was being operated outside the tested range of acceptable temperatures. You are correct that this was also a management failure since NASA engineers told management the solid booster should not be flown at those untested temperatures.
Columbia was also lost due to a component failure, in that case the breakage of foam insulation on the shuttle fuel tank. I call it a failure since it was not designed to break in that way. This was a double management failure since the shuttle was allowed to launch with known faulty foam and NASA management ignored efforts to photograph the shuttle for damage.
NASA management could have prevented both tragedies by requiring testing and modification of those components or modification of launch conditions to match tested scenarios.
had the O rings been operated in the temp range that NASA knew did not allow blowby they could have flown forever with that "known defect"
I am in more agreement with you about the foam. but its still more a management issue then a component one. IN both cases as you and I point out management could have fixed the problem but elected to continue flying
none of these are in the range of the failure that cost the first B29...ie the engines were simply a component failure due to design issues. it would have been like an SSME exploding
edit...it is to me unlikely that Dragon2 has any "exploding engines or other parts" in it...Starliner has never flown so you dont know but thats doubtful as well
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#164
by
LaunchedIn68
on 03 Aug, 2018 14:28
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Any word yet that for DM1 the Crew Access Arm will be in place on the FSS at 39A? While not required, I would imagine they'd want to test procedures, fit checks, and access the capsule on an actual flight.
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#165
by
Roy_H
on 03 Aug, 2018 19:05
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So DM1 is ready to fly September, but ISS scheduling has no time until November. Even November looks busy.
How many crew hours will be required for DM1? Berthing and de-berthing, unloading some supplies (I would expect minimal, but does anyone know how much supplies, and time required?) Also apparently re-packing for some items to return to earth.
First half of September and first half of November there are only 3 crew members on ISS due to crew rotations. Most of October has full crew of 6. Original schedule FIFP (Feburary 2018) showed both Starliner and Dragon demo missions in September (sequentially one in first half of month then the other). HTV7 will occupy crew time between second half of August to first half October, and Dragon supplies via SPX second half of November to late December and finally Orbital from early November to January. So to my eyes, the crew is busier in November than September and best time would be second half of September to mid October.
If HTV7 was so time consuming, why was the demo originally scheduled during that time? Why is it now not acceptable?
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#166
by
abaddon
on 03 Aug, 2018 19:16
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So DM1 is ready to fly September
I must have missed that, where was that stated?
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#167
by
ChrisGebhardt
on 03 Aug, 2018 19:23
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So DM1 is ready to fly September, but ISS scheduling has no time until November. Even November looks busy.
How many crew hours will be required for DM1? Berthing and de-berthing, unloading some supplies (I would expect minimal, but does anyone know how much supplies, and time required?) Also apparently re-packing for some items to return to earth.
Enough that this becomes a problem with HTV-7 at the same time the crew handovers, Soyuz rotations, and crew reductions take place. Remember, beginning in October, total ISS crew will be reduce temporarily from 6 to 5 as Russia cuts back its crew compliment to just 2 people. There will also be internal elements to DM-1 that the Station crew will perform with this being the first Crew Dragon at ISS.
First half of September and first half of November there are only 3 crew members on ISS due to crew rotations. Most of October has full crew of 6. Original schedule FIFP (Feburary 2018) showed both Starliner and Dragon demo missions in September (sequentially one in first half of month then the other). HTV7 will occupy crew time between second half of August to first half October, and Dragon supplies via SPX second half of November to late December and finally Orbital from early November to January. So to my eyes, the crew is busier in November than September and best time would be second half of September to mid October.
If HTV7 was so time consuming, why was the demo originally scheduled during that time? Why is it now not acceptable?
HTV-7 is launching NET- 10 Sept. So crew time will not be dedicated to it in August.
DM-1 was never scheduled for the same time at HTV-7. DM-1 had a "work to" NET (No Earlier Than) date of 31 August. That is not, and was never, a scheduled launch date.
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#168
by
ChrisGebhardt
on 03 Aug, 2018 19:23
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#169
by
Comga
on 03 Aug, 2018 19:34
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So DM1 is ready to fly September, but ISS scheduling has no time until November. Even November looks busy.
How many crew hours will be required for DM1? Berthing and de-berthing,...
(snip)
Dragon 2 (and CST-100) will dock autonomously, not be berthed.
It's certain that the astronauts will be fully engaged in monitoring the approach and docking, probably with a hand over a safety switch, but just not in active control and not executing a berthing.
However, the time to monitor approach and docking shouldn't be all that much.
Interesting priorities.
And if Boeing's second flight can be extended to a full ISS rotation, as a lifeboat for three astronauts, wouldn't it make sense to let SpaceX's DM-1 launch early and wait for astronaut availability on orbit while docked?
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#170
by
Alexphysics
on 03 Aug, 2018 19:35
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One note to remember, Dragon 2 WON'T BERTH.
Dragon 2 WILL DOCK
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#171
by
ChrisGebhardt
on 03 Aug, 2018 19:41
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So DM1 is ready to fly September, but ISS scheduling has no time until November. Even November looks busy.
How many crew hours will be required for DM1? Berthing and de-berthing,...
(snip)
Dragon 2 (and CST-100) will dock autonomously, not be berthed.
It's certain that the astronauts will be fully engaged in monitoring the approach and docking, probably with a hand over a safety switch, but just not in active control and not executing a berthing.
However, the time to monitor approach and docking shouldn't be all that much.
Interesting priorities.
Not sure what you mean by interesting priorities. Are you saying an uncrewed test flight carrying minimal supplies to ISS should take precedent over a needed crew rotation and a needed and large-scale resupply and science delivery mission (HTV-7)? If so, why?
And if Boeing's second flight can be extended to a full ISS rotation, as a lifeboat for three astronauts, wouldn't it make sense to let SpaceX's DM-1 launch early and wait for astronaut availability on orbit while docked?
Boeing's CFT being potentially being extended to a six month mission has nothing to do with SpaceX's 14-day DM-1 flight. They are in no way connected to each other.
And how would launching the uncrewed DM-1 Dragon in September and having it loiter on orbit for two months before approaching ISS be a realistic test of its launch, rendezvous, docking profile it will fly to Station -- a key component of the DM-1 test flight?
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#172
by
Tomness
on 03 Aug, 2018 19:55
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Will Commercial Crew get to unitize 3-6 hr docking? that be nice feature for the Astronauts.
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#173
by
whitelancer64
on 03 Aug, 2018 20:08
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Will Commercial Crew get to unitize 3-6 hr docking? that be nice feature for the Astronauts.
They have to. Neither capsule has a toilet.
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#174
by
DigitalMan
on 03 Aug, 2018 20:20
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Will Commercial Crew get to unitize 3-6 hr docking? that be nice feature for the Astronauts.
They have to. Neither capsule has a toilet.
That's what I thought, but what do you make of this from reddit?
christinaremter USA 3 points 3 hours ago
is there a bathroom on the new commercial flights? dragon and starliner crew
nasa NASA 6 points 3 hours ago
For Dragon, yes. -Bob
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#175
by
whitelancer64
on 03 Aug, 2018 20:21
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Will Commercial Crew get to unitize 3-6 hr docking? that be nice feature for the Astronauts.
They have to. Neither capsule has a toilet.
That's what I thought, but what do you make of this from reddit?
christinaremter USA 3 points 3 hours ago
is there a bathroom on the new commercial flights? dragon and starliner crew
nasa NASA 6 points 3 hours ago
For Dragon, yes. -Bob
That's news to me, and probably also to everyone else here!!!
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#176
by
Comga
on 03 Aug, 2018 21:23
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Dragon 2 (and CST-100) will dock autonomously, not be berthed.
It's certain that the astronauts will be fully engaged in monitoring the approach and docking, probably with a hand over a safety switch, but just not in active control and not executing a berthing.
However, the time to monitor approach and docking shouldn't be all that much.
Interesting priorities.
Not sure what you mean by interesting priorities. Are you saying an uncrewed test flight carrying minimal supplies to ISS should take precedent over a needed crew rotation and a needed and large-scale resupply and science delivery mission (HTV-7)? If so, why?
Because the future of the ISS depends on Commercial Crew certification and time is ticking, with a pretty firm deadline approaching vis-à-vis Soyuz availability.
And if Boeing's second flight can be extended to a full ISS rotation, as a lifeboat for three astronauts, wouldn't it make sense to let SpaceX's DM-1 launch early and wait for astronaut availability on orbit while docked?
Boeing's CFT being potentially being extended to a six month mission has nothing to do with SpaceX's 14-day DM-1 flight. They are in no way connected to each other.
Of course they are connected. They are the competing entries in the Commercial Crew program.
If Boeing was to have a significant problem (which they probably do not) SpaceX as the other Commercial Crew provider is supposed to take up the slack. If there was a delay to Boeing's first mission with crew, where they are planning on bringing along a third crew member and staying for a full rotation, the same should apply to SpaceX.
If it's a necessary service, both providers should be primed to provide it. That's the point of two contractors.
And how would launching the uncrewed DM-1 Dragon in September and having it loiter on orbit for two months before approaching ISS be a realistic test of its launch, rendezvous, docking profile it will fly to Station -- a key component of the DM-1 test flight?
That is not what was suggested, which was to launch as soon as the time could be found in the astronauts' schedule for approach and docking, and have Dragon 2 "loiter" docked. That reduce the amount of quick unload cargo on DM-1, like fresh fruit or biological samples, but those would be the tradeoffs for getting a Commercial Crew flight in ASAP.
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#177
by
ChrisGebhardt
on 03 Aug, 2018 23:01
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Dragon 2 (and CST-100) will dock autonomously, not be berthed.
It's certain that the astronauts will be fully engaged in monitoring the approach and docking, probably with a hand over a safety switch, but just not in active control and not executing a berthing.
However, the time to monitor approach and docking shouldn't be all that much.
Interesting priorities.
Not sure what you mean by interesting priorities. Are you saying an uncrewed test flight carrying minimal supplies to ISS should take precedent over a needed crew rotation and a needed and large-scale resupply and science delivery mission (HTV-7)? If so, why?
Because the future of the ISS depends on Commercial Crew certification and time is ticking, with a pretty firm deadline approaching vis-à-vis Soyuz availability.
And if Boeing's second flight can be extended to a full ISS rotation, as a lifeboat for three astronauts, wouldn't it make sense to let SpaceX's DM-1 launch early and wait for astronaut availability on orbit while docked?
Boeing's CFT being potentially being extended to a six month mission has nothing to do with SpaceX's 14-day DM-1 flight. They are in no way connected to each other.
Of course they are connected. They are the competing entries in the Commercial Crew program.
If Boeing was to have a significant problem (which they probably do not) SpaceX as the other Commercial Crew provider is supposed to take up the slack. If there was a delay to Boeing's first mission with crew, where they are planning on bringing along a third crew member and staying for a full rotation, the same should apply to SpaceX.
If it's a necessary service, both providers should be primed to provide it. That's the point of two contractors.
And how would launching the uncrewed DM-1 Dragon in September and having it loiter on orbit for two months before approaching ISS be a realistic test of its launch, rendezvous, docking profile it will fly to Station -- a key component of the DM-1 test flight?
That is not what was suggested, which was to launch as soon as the time could be found in the astronauts' schedule for approach and docking, and have Dragon 2 "loiter" docked. That reduce the amount of quick unload cargo on DM-1, like fresh fruit or biological samples, but those would be the tradeoffs for getting a Commercial Crew flight in ASAP.
Regardless of eventual "one provider can pick up the slack if the other has a mishap" built-in element to CCP, that future consideration is not what the uncrewed test flights are meant to demonstrate and certify. It appears to me that you are advocating that NASA and SpaceX radically change just Dragon's uncrewed test flight just to rush to get it launched and then perform a mission that doesn't match the test timelines that have been under development -- and that the only reason for suggested, radical change for the
uncrewed SpX demo is because Boeing's
crewed test flight (not uncrewed test flight) might potentially perhaps be extended (which is has not been decided on) in duration. And you're saying SpaceX and NASA should do that for the uncrewed flight instead of waiting to launch until November when the SpX DM-1 uncrewed test can be carried out as intended. I really do not see the connection. It's apples and oranges; uncrewed by one provider and crewed by the other provider -- all based on a potential scenario of Boeing's CFT maybe getting an extension.
I fully understand and am aware that Soyuz seats expire for the USOS in 2019. But how is rushing and changing things last minute for only 1 provider's uncrewed test going to change that and future timelines? NASA is saying there isn't time to do SpX DM-1 until November. So what do you gain by launching early and "dock loitering"? Nothing.
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#178
by
Comga
on 04 Aug, 2018 03:39
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It’s not rushing, Chris
It’s minimizing wasted time.
And I am not advocating doing anything different with DM-1 than waiting to unpack it.
The only reason to do the unmanned test flights is to learn things about the system ahead of the crewed flights. It will take time to digest whatever is observed and the Commercial Crew safety reviews have all taken longer than originally anticipated. Earlier launch buys more time.
ASAP puts the far end of the probable date range for certification past the end date for Soyuz availability. That’s pretty frightening and NASA should be doing what they can to buy extra time before then. Right now they are prioritizing HTV-7 over DM-1 and the path to Commercial Crew. Although there are a plethora of “moving parts” in the ISS program that need to mesh, I find that curious and concerning.
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#179
by
ChrisGebhardt
on 04 Aug, 2018 14:31
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It’s not rushing, Chris
Needlessly advancing a launch date to satisfy a personal desire to get the capsule off the ground as soon as possible just so it can wait months or weeks for the crew to have time to get to it isn't rushing? OK.
It’s minimizing wasted time.
What wasted time? NASA is saying point blank that there is no time in SpaceX's prep schedule and the ISS schedule to launch before November. Please show me were there is "wasted time" as I'm not seeing it.
And I am not advocating doing anything different with DM-1 than waiting to unpack it.
That, in it's very essence , is "doing [something] different with DM-1" as DM-1 has not been designed or conceived of as a loiter/docked mission.
The only reason to do the unmanned test flights is to learn things about the system ahead of the crewed flights.
Glad you bring this up. This push to November because there is no time to get the mission in before then might actually allow SpaceX time to swap out the parachute reef line cutters on DM-1 Dragon to the new ones that will be use on DM-2 onward. Testing that critical system on DM-1 instead of the first crew test could end up being a nice benefit of there not being time in the overall ISS and crew schedule until November, and as you put it, would allow the teams to "learn things about the system ahead of crewed flights".... something there wouldn't be time for in a scenario you propose of launching as soon as possible just to get the capsule into orbit.
It will take time to digest whatever is observed and the Commercial Crew safety reviews have all taken longer than originally anticipated. Earlier launch buys more time.
Of course it will take time. I see no one on here (and nothing in my answers) that asserts a different stance. But an important element of this is the complete overview of the entire integrated system through the entire flight envelope. Launching early just for the sake of launching early does not "buy more time" when integrated system performance relies on data gathered during EOM ops.
https://www.nasaspaceflight.com/2018/07/crew-dragon-cape-iss-schedule-drive-dm-1-date/
