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Prober
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« Reply #15 on: 06/04/2011 08:30 PM » |
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It will certainly be a very exciting experiment that could be a game-changer for in-space propulsion. It's nice to see the capabilities of the ISS being utilised to help us go beyond LEO. 
Actually, this is make work for the ISS. There is nothing unique that the ISS provides for this experiment. In fact, there are more safety hindrances, since it is a manned vehicle. Any other spacecraft would be better for this. The kicker is that it got a free ride.
I would think this might have been a decent payload for the SpaceX heavy?
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Space Pete
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« Reply #16 on: 06/04/2011 08:37 PM » |
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I would think this might have been a decent payload for the SpaceX heavy? I suppose that would depend on the size of the demo payload itself - designing a larger demo would cost more money and take more time. The idea of using ISS is to do small demo payloads and hitch a ride on an already manifested launcher, thus proving concepts cheaper and quicker than developing a larger payload that would need its own bus and dedicated launcher.
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Jim
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« Reply #17 on: 06/04/2011 09:06 PM » |
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The idea of using ISS is to do small demo payloads and hitch a ride on an already manifested launcher, thus proving concepts cheaper and quicker than developing a larger payload that would need its own bus and dedicated launcher.
You just don't get it. Forget the transfer, just leave on the Dragon and test it on there. There is no need for it to go the "extra" distance. Dragon can provide all the same services and will provide most on the basic transfer mission. You don't know if there is less power or data available on the Dragon. Duration is not a factor, this is a short duration experiment. Burn all the prop and it is done. The reason not to go to the ISS is cost. Eliminate the transfer.
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Jim
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« Reply #18 on: 06/04/2011 09:07 PM » |
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I would think this might have been a decent payload for the SpaceX heavy?
No, this is a small payload
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Jim
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« Reply #19 on: 06/04/2011 09:13 PM » |
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Dragon could do that or Cygnus or other spacecraft buses.
I don't doubt that's true, but then you'd have to adapt a currently unproven Cygnus or Dragon or other bus for use with this experiment, which would likely cost more money and take more time than just putting it on ISS, thus harming the NOFBX business case since they want a flight demo as quickly as possible.
Lots of experiments on ISS *could* be done elsewhere, but the question is *should* it be done elsewhere?
How the hell do you think it is getting to the ISS? It is going to have to be integrated on a Dragon. Also, the ISS experiment isn't built yet, there is nothing to adapt. Yes, experiments should be done where it is cheaper and not to make work for the ISS. This is the same thing that happened with the shuttle.
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Space Pete
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« Reply #20 on: 06/04/2011 09:19 PM » |
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You just don't get it. Forget the transfer, just leave on the Dragon and test it on there. There is no need for it to go the "extra" distance. Dragon can provide all the same services and will provide most on the basic transfer mission.
You don't know if there is less power or data available on the Dragon. Duration is not a factor, this is a short duration experiment. Burn all the prop and it is done.
The reason not to go to the ISS is cost. Eliminate the transfer.
A) If we eliminate the transfer, we reduce the scientific return of the experiment. That's one of the reasons why they're going to ISS - to do things that can't be done elsewhere. B) The reason for going to ISS is that if offers the shortest conceivable time to flight (18 months). ISPS have stated that they want to get the demo done as quickly as possible, so that potential customers can gain confidence in the system. In other words: They value short schedules over low cost. C) Duration is not a factor? Not according to the Program Manager for the NOFBX demo: Our company wants to characterize how the system behaves and performs over time by running selected tests after long quiescent/dormant periods when the system is completely unpowered Have you actually read this? http://blogs.nasa.gov/cm/blog/ISS%20Science%20Blog/posts/post_1307128426352.html
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Space Pete
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« Reply #21 on: 06/04/2011 09:24 PM » |
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How the hell do you think it is getting to the ISS? It is going to have to be integrated on a Dragon.
Also, the ISS experiment isn't built yet, there is nothing to adapt.
Yes, experiments should be done where it is cheaper and not to make work for the ISS. This is the same thing that happened with the shuttle.
Yes, Dragon as a cargo carrier will be proven once CRS flights start. But DragonLab, which would have all the capabilities necessary to support this payload, may well take longer to develop and fly. Thus, going to ISS would be faster. I agree that if it's cheaper to go to ISS, then it should be done. But, it isn't always necessarily about cost. ISS may be more expensive, but it may also offer more scientific benefits, such a transfer. Thus, the addition cost may be justified in some cases.
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A_M_Swallow
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« Reply #22 on: 06/04/2011 10:33 PM » |
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That could be a design error.
yeah, right. No, your assumptions are errors.
This is an experiment, there is nothing said about using it for reboost or refueling. The refueling aspect would require testing too. Was that mentioned? So to follow your thought process, since the ISS is doing salmonella vaccination experiments, the astronauts must be using the vaccine because it is there. Think before posting. Others can draw conclusions about your post.
Jim showing that he cannot think strategically again. The ISS will need reboosting several times over its remaining life. The chooses are: a. add a test NOFBX thruster to the ISS and when that works replace it with a refuellable NOFBX to perform the reboosting. b. or add a refuellable NOFBX thruster to the ISS which can do some reboosting work when it has passed the tests.
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Prober
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« Reply #23 on: 06/04/2011 11:38 PM » |
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I would think this might have been a decent payload for the SpaceX heavy?
No, this is a small payload
Think you missed the point i was trying to make Jim. The heavy test would be a "test" and this payload is frankly expendable.
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QuantumG
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« Reply #24 on: 06/05/2011 12:46 AM » |
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Nitrous-based mixed monoprops are still considered "too dangerous" by many. If you look at Firestar's previous activities with their program you'll see that they've been primarily concerned with obsoleting this common wisdom.
Nothing says "it's safe" like a NASA reviewed experiment on the ISS.
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mmeijeri
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« Reply #25 on: 06/05/2011 09:45 AM » |
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Nothing says "it's safe" like a NASA reviewed experiment on the ISS.
Unless it blows up and takes out the ISS...  Which of course it won't.
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Robotbeat
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« Reply #26 on: 06/05/2011 09:55 AM » |
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I'm a little wary of high energy (no catalyst required) monoprops. Is it such a good idea to put the station at risk for the first space test of a mixed-monoprop? If it's slightly contaminated, it's like a pretty good sized bomb waiting to go off right on your porch if the flash-back arrestors fail or if there's a sudden jolt (again, if it's contaminated). It's a "proprietary" technology, so we can't even SPECULATE on what hidden dangers lie there, we just have to "trust" that company's word.
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QuantumG
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« Reply #27 on: 06/05/2011 10:05 AM » |
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You might have to, but I'm pretty sure NASA won't be.
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Space Pete
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« Reply #28 on: 06/05/2011 12:26 PM » |
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You might have to, but I'm pretty sure NASA won't be. Exactly. It is pretty well acknowledged that NASA have a very conservative attitude when it comes to flight crew safety. So if NASA have signed off on it, then that's enough confirmation for me that it's safe.
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Prober
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« Reply #29 on: 06/05/2011 06:03 PM » |
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You might have to, but I'm pretty sure NASA won't be.
Exactly. It is pretty well acknowledged that NASA have a very conservative attitude when it comes to flight crew safety. So if NASA have signed off on it, then that's enough confirmation for me that it's safe.
If this pkg wanted to be put on the Space shuttle a couple of years off the Challenger you might get a different answer. My question, has NASA changed that much?
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