Quote from: DaveH62 on 08/25/2011 04:15 amJorgeI don't know what you mean by "flight system updates".I thought electronic avionics were added around 2000, and they switched to all digital displays for piloting the Shuttle. Perhaps not for docking though.
JorgeI don't know what you mean by "flight system updates".
Quote from: Jorge on 08/25/2011 04:25 amI don't know what you mean by "flight system updates".I thought electronic avionics were added around 2000, and they switched to all digital displays for piloting the Shuttle. Perhaps not for docking though.
I don't know what you mean by "flight system updates".
This thread just further validates my opinion that the sooner we get CST-100 and Biglow going NASA will still be worrying about window placement, fiber optics, and "piloting".
Quote from: RocketScientist327 on 08/23/2011 03:29 amThis thread just further validates my opinion that the sooner we get CST-100 and Biglow going NASA will still be worrying about window placement, fiber optics, and "piloting".Indeed; what a silly requirement.In the entire history of ISS (and Shuttle-Mir), did an orbiter ever dock solely by eye? Indeed, has any US vehicle performed such a maneuver since ASTP?Modern cameras are so cheap and light that it's lighter (and safer!) to just put on a bunch of redundant cameras on the vehicle...
Maybe I'm all wrong, and someone can explain why hatch windows are only good for seeing the close-out crew give you the "thumbs up".
Quote from: corrodedNut on 08/26/2011 02:52 amMaybe I'm all wrong, and someone can explain why hatch windows are only good for seeing the close-out crew give you the "thumbs up". They aren't forward facing
Indeed; what a silly requirement.In the entire history of ISS (and Shuttle-Mir), did an orbiter ever dock solely by eye? Indeed, has any US vehicle performed such a maneuver since ASTP?
Quote from: simonbp on 08/25/2011 07:44 pmIndeed; what a silly requirement.In the entire history of ISS (and Shuttle-Mir), did an orbiter ever dock solely by eye? Indeed, has any US vehicle performed such a maneuver since ASTP?Yes, just like the lack of a LAS use on Apollo showed that including it as a requirement on shuttle as silly.....Just because a safety system was not needed previously does not mean it is silly or frivolous at all.
Quote from: Ronsmytheiii on 08/26/2011 03:25 amQuote from: simonbp on 08/25/2011 07:44 pmIndeed; what a silly requirement.In the entire history of ISS (and Shuttle-Mir), did an orbiter ever dock solely by eye? Indeed, has any US vehicle performed such a maneuver since ASTP?Yes, just like the lack of a LAS use on Apollo showed that including it as a requirement on shuttle as silly.....Just because a safety system was not needed previously does not mean it is silly or frivolous at all.Just because the word "safety" is used doesn't mean it's actually essential for safety. NASA can make it so that every single bolt must have a stack of pages written about it a foot thick. In the name of safety. If they choose.
Just because the word "safety" is used doesn't mean it's actually essential for safety. NASA can make it so that every single bolt must have a stack of pages written about it a foot thick. In the name of safety. If they choose.
...Just because the almighty SpaceX does not have a window does not mean it is not needed.
Of course not. And just because NASA has "always done it that way" does not mean it's necessarily the only way it can be done or even the safest.As Jorge said, a periscope (or something like it) would probably meet the intent of the requirement, if not the word. That's what I'm concerned about: the way the safety "requirement" is worded becoming more important than the actual safeness inferred by such a feature. The possibility that equivalently-safe ways of doing the same thing will be excluded because of red-tape instead of sound systems engineering reasons. There has to be flexibility on the exact way of accomplishing equivalent levels of safety or commercial crew will not be affordable or on schedule.It'd be ironic if a Soyuz-type approach (i.e. periscope) not being allowed for commercial crew leads to delays causing NASA to continue to be reliant on Soyuz. Ironic, not surprising.
I agree with you on the periscope, but still disagree on the intent. When one is near a large, delicate, and expensive spacecraft like ISS passive ability to back out will be needed, whether it is a periscope or window. I am sure NASA will include a periscope if asked, but I reject the notion that the requirement is frivolous, again NASA has much more experience with docking than commercial.
Quote from: Robotbeat on 08/26/2011 02:08 pmOf course not. And just because NASA has "always done it that way" does not mean it's necessarily the only way it can be done or even the safest.As Jorge said, a periscope (or something like it) would probably meet the intent of the requirement, if not the word. That's what I'm concerned about: the way the safety "requirement" is worded becoming more important than the actual safeness inferred by such a feature. The possibility that equivalently-safe ways of doing the same thing will be excluded because of red-tape instead of sound systems engineering reasons. There has to be flexibility on the exact way of accomplishing equivalent levels of safety or commercial crew will not be affordable or on schedule.It'd be ironic if a Soyuz-type approach (i.e. periscope) not being allowed for commercial crew leads to delays causing NASA to continue to be reliant on Soyuz. Ironic, not surprising.I agree with you on the periscope, but still disagree on the intent. When one is near a large, delicate, and expensive spacecraft like ISS passive ability to back out will be needed, whether it is a periscope or window....
As has already been stated before, there were real concrete reasons for needing a window in the docking process in the first place.
Quote from: Ronsmytheiii on 08/26/2011 01:16 pmAs has already been stated before, there were real concrete reasons for needing a window in the docking process in the first place. Except there isn't. As I said, cameras are small and cheap, so you can put four fully redundant cameras, each with its own separate string to the control panel, and it would still have less than 1/10 the mass impact on the vehicle as forward-looking window. And frankly, if they loose any major sensors during flight, docking will be aborted anyways, regardless of any windows.
Quote from: simonbp on 08/26/2011 04:03 pmQuote from: Ronsmytheiii on 08/26/2011 01:16 pmAs has already been stated before, there were real concrete reasons for needing a window in the docking process in the first place. Except there isn't. As I said, cameras are small and cheap, so you can put four fully redundant cameras, each with its own separate string to the control panel, and it would still have less than 1/10 the mass impact on the vehicle as forward-looking window. And frankly, if they loose any major sensors during flight, docking will be aborted anyways, regardless of any windows.Cameras are not neccessarily better. Yes, cameras *may* have less mass, but you trade that against power and data transfer for the camera plus an extra crew display. So you might not be less mess and you are trading against critical items like power and increasing the complexity of the system (which means cost, risk) etc.
Yeah, the trade could go different ways. But don't you think it should be up to the commercial crew provider to find the most cost-and-performance-optimal solution that meets the required level of safety?