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.
As you imply, No shuttle was ever lost due to a failure of a component
Quote from: TripleSeven on 08/03/2018 01:13 pmAs 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.
So DM1 is ready to fly September
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?
Quote from: Roy_H on 08/03/2018 07:05 pmSo DM1 is ready to fly SeptemberI must have missed that, where was that stated?
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)
Quote from: Roy_H on 08/03/2018 07:05 pmSo 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?
Will Commercial Crew get to unitize 3-6 hr docking? that be nice feature for the Astronauts.
Quote from: Tomness on 08/03/2018 07:55 pmWill Commercial Crew get to unitize 3-6 hr docking? that be nice feature for the Astronauts.They have to. Neither capsule has a toilet.
christinaremter USA 3 points 3 hours ago is there a bathroom on the new commercial flights? dragon and starliner crewnasa NASA 6 points 3 hours ago For Dragon, yes. -Bob
Quote from: whitelancer64 on 08/03/2018 08:08 pmQuote from: Tomness on 08/03/2018 07:55 pmWill 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?Quotechristinaremter USA 3 points 3 hours ago is there a bathroom on the new commercial flights? dragon and starliner crewnasa NASA 6 points 3 hours ago For Dragon, yes. -Bob
Quote from: Comga on 08/03/2018 07:34 pmDragon 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?
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.
Quote from: Comga on 08/03/2018 07:34 pmAnd 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?
Quote from: ChrisGebhardt on 08/03/2018 07:41 pmQuote from: Comga on 08/03/2018 07:34 pmDragon 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.QuoteQuote from: Comga on 08/03/2018 07:34 pmAnd 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.QuoteAnd 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.
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.