Quote from: Dudely on 10/17/2014 12:21 pmCST-100 has integrated LAS too. It also aims to be a re-used capsule (not sure if they plan to do this when flying for Bigelow or what, but I did hear about it), including the heat shield and presumably the LAS too.It has a pusher LAS in the trunk. It is abandoned before reentry.
CST-100 has integrated LAS too. It also aims to be a re-used capsule (not sure if they plan to do this when flying for Bigelow or what, but I did hear about it), including the heat shield and presumably the LAS too.
After reentering the atmosphere, the CST-100's three main parachutes open at an altitude of approximately 12,000 feet. When the capsule reaches about 5,000 feet, the base heat shield drops away and six air bags inflate with a mixture of air and nitrogen two minutes before landing to cushion the passengers from the impact.
There was a letter circulated from a NASA higher-up that explained the reasoning behind dropping SNC. The big issue was Dreamchaser could run into production or testing delays, which at this point would make the program laughably pointless if the ISS gets decommissioned in 2020. Not a difficult choice at all.
Quote from: bob the martian on 10/15/2014 04:07 pmQuote from: Proponent on 10/15/2014 09:17 amQuote from: cuddihy on 10/07/2014 11:32 amSince their [SpaceX's] bid was lower to begin with, it's less risk to proceed and if the GAO rules against NASA, it's likely the higher cost bid goes away than the lower cost.I'm not so sure about that.It's not just about cost, it's also about technical and schedule risk. Say what you will about Boeing, their processes are such that NASA has a higher confidence in their ability to meet schedule. NASA is less confident in SpaceX, whose processes are not as mature, and who've had issues with schedule in the past. They're a damn sight better than they were two years ago, but still. Better to spend $4 bn on a system that's almost guaranteed to come in on time and to spec than $2 bn on a system that may be late or fail to meet spec. Not that I expect SpaceX to fail or even be late; I'm just presenting the reasoning why it doesn't strictly come down to cost. If it comes down to choosing a single provider (which would be stupid for any number of reasons, but that's another thread), there's no way it won't be Boeing. That's not (just) politics or pork. NASA can make a good technical case for picking Boeing over SpaceX, regardless of the cost difference.Completely missing from your analysis: unmanned Dragon capsule in orbit right now. SpaceX has demonstrated and operated a nearly identical design capsule in orbit (and, for most, at ISS) 6 times, now (with two Dragon 2 vehicles under advanced construction), while Boeing barely even has a pressure vessel and hasn't built a similar capsule system in decades. Also, SpaceX is way closer to demonstrating abort, both pad and in-flight. Also, they JUST developed Dragon v1 and flew to ISS, which proves they know how to get the job done quickly and at low budget, just like they claim.Calling SpaceX "higher risk" than Boeing at this point is /absurd/.
Quote from: Proponent on 10/15/2014 09:17 amQuote from: cuddihy on 10/07/2014 11:32 amSince their [SpaceX's] bid was lower to begin with, it's less risk to proceed and if the GAO rules against NASA, it's likely the higher cost bid goes away than the lower cost.I'm not so sure about that.It's not just about cost, it's also about technical and schedule risk. Say what you will about Boeing, their processes are such that NASA has a higher confidence in their ability to meet schedule. NASA is less confident in SpaceX, whose processes are not as mature, and who've had issues with schedule in the past. They're a damn sight better than they were two years ago, but still. Better to spend $4 bn on a system that's almost guaranteed to come in on time and to spec than $2 bn on a system that may be late or fail to meet spec. Not that I expect SpaceX to fail or even be late; I'm just presenting the reasoning why it doesn't strictly come down to cost. If it comes down to choosing a single provider (which would be stupid for any number of reasons, but that's another thread), there's no way it won't be Boeing. That's not (just) politics or pork. NASA can make a good technical case for picking Boeing over SpaceX, regardless of the cost difference.
Quote from: cuddihy on 10/07/2014 11:32 amSince their [SpaceX's] bid was lower to begin with, it's less risk to proceed and if the GAO rules against NASA, it's likely the higher cost bid goes away than the lower cost.I'm not so sure about that.
Since their [SpaceX's] bid was lower to begin with, it's less risk to proceed and if the GAO rules against NASA, it's likely the higher cost bid goes away than the lower cost.
Quote from: guckyfan on 10/17/2014 12:49 pmIt has a pusher LAS in the trunk. It is abandoned before reentry.CST-100 does not have a trunk. Only Dragon has that.
It has a pusher LAS in the trunk. It is abandoned before reentry.
You are right. Is it called a SM with CST-100?
As far as "off the shelf" non rad-hardened components. . . have you seen the equipment that flies on the ISS? They use basic laptops with no problem. Many modern rockets and satellites don't use rad-hardened components. Lets also not forget that they had triple redundancy for Dragon 1 too, including the rocket, and they were not required to do this. They also had 30% engineering margins.
Quote from: clongton on 10/18/2014 12:13 amQuote from: guckyfan on 10/17/2014 12:49 pmIt has a pusher LAS in the trunk. It is abandoned before reentry.CST-100 does not have a trunk. Only Dragon has that.You are right. Is it called a SM with CST-100?
1) They use basic laptops with no problem.2) Many modern rockets and satellites don't use rad-hardened components.3) Lets also not forget that they had triple redundancy for ... the rocket4) They also had 30% engineering margins.
[You are right. Is it called a SM with CST-100?
1) Not for safety critical systems2) They do for CPUs, memory, etc.3) V1.0 was not three-string4) 40% in most cases
I'm actually very surprised to hear V 1.0 was not triple redundant.
Quote from: Patchouli on 10/23/2014 05:10 amI'm actually very surprised to hear V 1.0 was not triple redundant.It was triple redundant. More here http://www.parabolicarc.com/2012/11/14/44264/
Quote from: guckyfan on 10/18/2014 03:29 amQuote from: clongton on 10/18/2014 12:13 amQuote from: guckyfan on 10/17/2014 12:49 pmIt has a pusher LAS in the trunk. It is abandoned before reentry.CST-100 does not have a trunk. Only Dragon has that.You are right. Is it called a SM with CST-100?The names are descriptive. The thunk is little more than a mechanical transfer tube. Yes, it holds the solar panels and act as radiator. That's it. The CST SM has the LaS, the RCS, propellant and many extra things. Is a different way or arranging the vehicle.