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The Space Race was about Power Projection - Miles O'Brien
On Saturday, February 4, 2017 at 10:42:55 AM UTC-5, Jeff Findley wrote:
In article , says... Scott Kozel wrote: Columbia could have been saved; if they used ground based telescopes to find the damage, then they would have had 2 weeks to come up with a patch from either material on board or material sent up on an expendable rocket, then EVAs to apply the patch. The ability to patch would have been marginal, but they would have had a good shot at a safe landing. Do you understand what was damaged on Columbia? I don't think you could have seen it with a ground based telescope and even if you could the Shuttle would have been a write off because there was no way to effect a repair on orbit. There's no way to 'patch' that kind of damage. No way? Au contraire. It is quite possible that *duct tape* might have gotten them home. The Air Force has a program called "ABDR" that teaches how to do such repairs. They will cut things like soda cans and flatten them out and then duct tape them onto holes on a jet's wing or fuselage as a viable patch. So for doing a MacGyver-style Aircraft Battle Damage Repair of Columbia's wing leading edge, you scour the crew cabin for some flat bendable piece of metal. Maybe use clipboards. Whatever. Then go out and tape it over the gaping hole. On day of Entry, hope it holds long enough to get you home. Wrong. The wing leading edge was reinforced carbon-carbon composite. This was the material on the shuttle which could withstand the most reentry heating. This isn't something you can "MacGyver" with any spare parts on board Columbia. That depends on the exact nature of the damage, and given that it wasn't surveyed by EVA or by shuttle-based camera or by telescope, we don't know whether it was a big hole or a small hole, or whether it was on the leading edge or behind of there. That could not be ascertained after the fact from the debris on the ground. Sending another shuttle on a rescue or repair mission would have had its own risks to that vehicle and crew, so that would need to be considered carefully before making that decision. That is why I suggested sending an expendable rocket with materials to for Columbia crew to make an emergency patch. Titanium sheets and sheets of ablative material and fasteners, for example. As far as to whether an emergency patch would work well enough to at least make a normal landing, NASA investigators determined that on-orbit repair by the shuttle astronauts was possible but overall considered high risk, primarily due to the uncertain resiliency of the repair using available materials and the anticipated high risk of doing additional damage to the Orbiter. And again, that would depend on the exact nature of the damage, and that is unknown due to the fact that they never made any attempt to examine it. The smaller the hole the higher the chance of a successful emergency repair. A huge hole might be impossible. The problem is that they could have known the nature of the damage on day 2 of a 14-day flight, but there was never any effort to determine the nature of the damage let alone try to repair it or come to a conclusion about whether or not it could be repaired. Saying stuff like, "Well given issues in the STS there was bound to be a disaster sooner or later" is not an acceptable conclusion, IMHO. Never the case in aviation or aerospace. Yes there are risks in flying 120+ STS missions, but on this particular mission there could have been a much better outcome, but they didn't even -try- to assess the damage let alone make a decision about what to do about it. That is what I meant by this mission being a management failure and not a purely technological failure. |
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The Space Race was about Power Projection - Miles O'Brien
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The Space Race was about Power Projection - Miles O'Brien
On Saturday, February 4, 2017 at 2:54:34 PM UTC-5, Jeff Findley wrote:
In article , says... Wrong. The wing leading edge was reinforced carbon-carbon composite. This was the material on the shuttle which could withstand the most reentry heating. This isn't something you can "MacGyver" with any spare parts on board Columbia. That depends on the exact nature of the damage, and given that it wasn't surveyed by EVA or by shuttle-based camera or by telescope, we don't know whether it was a big hole or a small hole, or whether it was on the leading edge or behind of there. That could not be ascertained after the fact from the debris on the ground. True there was no direct evidence. But, based on camera video the size of the chunk and its velocity when it hit the wing leading edge was estimated. So, a ground test was performed which was quite shocking in the size of the hole it created. From Wikipedia: As demonstrated by ground experiments conducted by the Columbia Accident Investigation Board, this likely created a 6-to-10-inch (15 to 25 cm) diameter hole, allowing hot gases to enter the wing when Columbia later re-entered the atmosphere. That's a huge hole when you consider the aerodynamic heating at hypersonic speeds encountered during reentry. It is still unknown how large the hole was and whether it was on the leading edge, or rearward where it would have considerably lower reentry temperatures. Also the nature of the damage, was there enough internal structure to support a patch or was that severely damaged? We don't know because nobody looked. If they did an EVA or had a Canadarm with a remote camera, they could have made a very accurate assessment of whether it was repairable, and on day 2. If clearly unrepairable, then a rescue mission would be the only way to rescue the crew. They would have another 12 days to mount that. Sending another shuttle on a rescue or repair mission would have had its own risks to that vehicle and crew, so that would need to be considered carefully before making that decision. So? Make it an all volunteer crew (you'd only need a minimal crew anyway to make room for the crew being rescued). Besides, rescue crews of all sorts are quite often at higher risk than when performing training. When you're trying to save someone's life, many people will take that risk. Considering many of them came to NASA from the military, I'd wager that you'd far more volunteers than you'd need. I mentioned the vehicle as well, you have one in orbit that may already be lost, and then a second one that you are rushing to launch. If the rescue mission meets disaster then the one in orbit doesn't get rescued, the fleet drops from four orbiters down to two orbiters, and at Endeavour's 1992 cost we're looking at least $3 billion per orbiter to replace the two that were just lost, and NASA will have a very difficult time finding that kind of funding. If the fleet stays at two orbiters then its functionality is rather limited. Plus the STS rescue mission will cost the typical $500+ million. That is why I suggested sending an expendable rocket with materials to for Columbia crew to make an emergency patch. Titanium sheets and sheets of ablative material and fasteners, for example. But that quite simply would not work for the RCC wing leading edge. The best NASA could do was make a repair kit for the tiles. Again, they didn't know whether it was the leading edge or the exact nature of the damage. The expendable rocket could send up several tons of various materials, using whatever was deemed necessary. As far as to whether an emergency patch would work well enough to at least make a normal landing, NASA investigators determined that on-orbit repair by the shuttle astronauts was possible but overall considered high risk, primarily due to the uncertain resiliency of the repair using available materials and the anticipated high risk of doing additional damage to the Orbiter. Almost certainly such a "repair" would have been higher risk than mounting a rescue mission. Again, rescue crews routinely risk their own lives. This wouldn't have been any different. They had no chance of surviving with the current damage. Repairing or attempting repairing would not have increased risk on a 0% chance of survival. Using an expendable rocket would not have risked human lives and it would have been far less expensive than a shuttle mission. Again, a damage assessment could have determined whether it was repairable. .... I have no disagreement with the remainder that was snipped, I agree that spaceflight is inherently risky, and about how Apollo/Saturn V was fortunate that no lives were lost. I fully accept the fact that it is risky and that disasters can occur. I just find it regrettable in how Columbia was lost, more on the basis of management failure than any technological failure. |
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The Space Race was about Power Projection - Miles O'Brien
In article ,
says... On Saturday, February 4, 2017 at 2:54:34 PM UTC-5, Jeff Findley wrote: In article , says... Wrong. The wing leading edge was reinforced carbon-carbon composite. This was the material on the shuttle which could withstand the most reentry heating. This isn't something you can "MacGyver" with any spare parts on board Columbia. That depends on the exact nature of the damage, and given that it wasn't surveyed by EVA or by shuttle-based camera or by telescope, we don't know whether it was a big hole or a small hole, or whether it was on the leading edge or behind of there. That could not be ascertained after the fact from the debris on the ground. True there was no direct evidence. But, based on camera video the size of the chunk and its velocity when it hit the wing leading edge was estimated. So, a ground test was performed which was quite shocking in the size of the hole it created. From Wikipedia: As demonstrated by ground experiments conducted by the Columbia Accident Investigation Board, this likely created a 6-to-10-inch (15 to 25 cm) diameter hole, allowing hot gases to enter the wing when Columbia later re-entered the atmosphere. That's a huge hole when you consider the aerodynamic heating at hypersonic speeds encountered during reentry. It is still unknown how large the hole was and whether it was on the leading edge, or rearward where it would have considerably lower reentry temperatures. Also the nature of the damage, was there enough internal structure to support a patch or was that severely damaged? We don't know because nobody looked. Bad enough it was starting to cause the control system to have trouble keeping the orbiter straight due to the increased drag on the side with the hole. You would not have gotten that with a small hole. See page 73 of the Columbia Accident Investigation Board's report. https://spaceflight.nasa.gov/shuttle/archives/sts- 107/investigation/CAIB_medres_full.pdf If they did an EVA or had a Canadarm with a remote camera, they could have made a very accurate assessment of whether it was repairable, and on day 2. I do not believe there was a Canadarm on that mission. EVA to that location would have been "sporty" for sure but could have confirmed the location and size of the hole. If clearly unrepairable, then a rescue mission would be the only way to rescue the crew. They would have another 12 days to mount that. From page 173 of the Columbia Accident Investigation Board's report: Because the NASA team could not verify that the repairs would survive even a modified re-entry, the rescue option had a considerably higher chance of bringing Columbia's crew back alive. Sending another shuttle on a rescue or repair mission would have had its own risks to that vehicle and crew, so that would need to be considered carefully before making that decision. So? Make it an all volunteer crew (you'd only need a minimal crew anyway to make room for the crew being rescued). Besides, rescue crews of all sorts are quite often at higher risk than when performing training. When you're trying to save someone's life, many people will take that risk. Considering many of them came to NASA from the military, I'd wager that you'd far more volunteers than you'd need. I mentioned the vehicle as well, you have one in orbit that may already be lost, and then a second one that you are rushing to launch. If the rescue mission meets disaster then the one in orbit doesn't get rescued, the fleet drops from four orbiters down to two orbiters, and at Endeavour's 1992 cost we're looking at least $3 billion per orbiter to replace the two that were just lost, and NASA will have a very difficult time finding that kind of funding. If the fleet stays at two orbiters then its functionality is rather limited. Plus the STS rescue mission will cost the typical $500+ million. From page 173 concerning a rescue mission using Atlantis: This rescue was considered challenging but feasible. To succeed, it required problem-free processing of Atlantis and a flawless launch countdown. If Program managers had understood the threat that the bipod foam strike posed and were able to unequivocally determine before Flight Day Seven that there was potentially catastrophic damage to the left wing, these repair and rescue plans would most likely have been developed, and a rescue would have been conceivable. Also, there is a heck of a lot of data in the report (mostly in Chapter 3) which led NASA to conclude that yes there was about a 6 inch diameter hole in the RCC panel(s) on the wing leading edge. This wasn't speculation or based solely on one test which fired foam at an RCC panel. It was supported by a lot of data gathered on launch (ground camera footage), on orbit (detailed radar data of debris which separated from the orbiter) and during reentry (various sensor failures, anomalies, and high temperature readings inside the wing). Jeff -- All opinions posted by me on Usenet News are mine, and mine alone. These posts do not reflect the opinions of my family, friends, employer, or any organization that I am a member of. |
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The Space Race was about Power Projection - Miles O'Brien
"Scott M. Kozel" wrote:
On Saturday, February 4, 2017 at 10:42:55 AM UTC-5, Jeff Findley wrote: In article , says... Scott Kozel wrote: Columbia could have been saved; if they used ground based telescopes to find the damage, then they would have had 2 weeks to come up with a patch from either material on board or material sent up on an expendable rocket, then EVAs to apply the patch. The ability to patch would have been marginal, but they would have had a good shot at a safe landing. Do you understand what was damaged on Columbia? I don't think you could have seen it with a ground based telescope and even if you could the Shuttle would have been a write off because there was no way to effect a repair on orbit. There's no way to 'patch' that kind of damage. No way? Au contraire. It is quite possible that *duct tape* might have gotten them home. The Air Force has a program called "ABDR" that teaches how to do such repairs. They will cut things like soda cans and flatten them out and then duct tape them onto holes on a jet's wing or fuselage as a viable patch. So for doing a MacGyver-style Aircraft Battle Damage Repair of Columbia's wing leading edge, you scour the crew cabin for some flat bendable piece of metal. Maybe use clipboards. Whatever. Then go out and tape it over the gaping hole. On day of Entry, hope it holds long enough to get you home. Wrong. The wing leading edge was reinforced carbon-carbon composite. This was the material on the shuttle which could withstand the most reentry heating. This isn't something you can "MacGyver" with any spare parts on board Columbia. That depends on the exact nature of the damage, and given that it wasn't surveyed by EVA or by shuttle-based camera or by telescope, we don't know whether it was a big hole or a small hole, or whether it was on the leading edge or behind of there. That could not be ascertained after the fact from the debris on the ground. We know with as much certainty as you can ever know anything. It was an approximately 12"x12" hole in RCC Panel 8, located toward the root of the left wing. So what don't you think we know? Sending another shuttle on a rescue or repair mission would have had its own risks to that vehicle and crew, so that would need to be considered carefully before making that decision. There was no such Shuttle ready for launch, so it's a moot point. That is why I suggested sending an expendable rocket with materials to for Columbia crew to make an emergency patch. Titanium sheets and sheets of ablative material and fasteners, for example. You suggest that because you don't understand things. As far as to whether an emergency patch would work well enough to at least make a normal landing, NASA investigators determined that on-orbit repair by the shuttle astronauts was possible but overall considered high risk, primarily due to the uncertain resiliency of the repair using available materials and the anticipated high risk of doing additional damage to the Orbiter. That's true if the damage is to heat tiles. However, the damage was not to heat tiles. It was to the RCC leading edge. And again, that would depend on the exact nature of the damage, and that is unknown due to the fact that they never made any attempt to examine it. The smaller the hole the higher the chance of a successful emergency repair. A huge hole might be impossible. ANY hole in the RCC is impossible. snip silliness -- "Ignorance is preferable to error, and he is less remote from the truth who believes nothing than he who believes what is wrong." -- Thomas Jefferson |
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The Space Race was about Power Projection - Miles O'Brien
"Scott M. Kozel" wrote:
On Saturday, February 4, 2017 at 2:54:34 PM UTC-5, Jeff Findley wrote: In article , says... Wrong. The wing leading edge was reinforced carbon-carbon composite. This was the material on the shuttle which could withstand the most reentry heating. This isn't something you can "MacGyver" with any spare parts on board Columbia. That depends on the exact nature of the damage, and given that it wasn't surveyed by EVA or by shuttle-based camera or by telescope, we don't know whether it was a big hole or a small hole, or whether it was on the leading edge or behind of there. That could not be ascertained after the fact from the debris on the ground. True there was no direct evidence. But, based on camera video the size of the chunk and its velocity when it hit the wing leading edge was estimated. So, a ground test was performed which was quite shocking in the size of the hole it created. From Wikipedia: As demonstrated by ground experiments conducted by the Columbia Accident Investigation Board, this likely created a 6-to-10-inch (15 to 25 cm) diameter hole, allowing hot gases to enter the wing when Columbia later re-entered the atmosphere. That's a huge hole when you consider the aerodynamic heating at hypersonic speeds encountered during reentry. It is still unknown how large the hole was and whether it was on the leading edge, or rearward where it would have considerably lower reentry temperatures. They're pretty damned sure they tracked the departing piece of the RCC during reentry. If the damage was 'rearward' from the RCC the reentry would have been successful, so everyone is just pretty damned sure where the damage was. Read the bloody report. Also the nature of the damage, was there enough internal structure to support a patch or was that severely damaged? We don't know because nobody looked. And nobody looked because nobody thought the RCC could be damage by a foam strike and tile damage wouldn't have led to loss of vehicle. If they did an EVA or had a Canadarm with a remote camera, they could have made a very accurate assessment of whether it was repairable, and on day 2. If they even looked in the right place. Again, nobody believed at the time that the RCC could be damaged by a foam strike. Kits to repair damaged tiles didn't exist until years after Columbia, so even finding tile damage would have made no difference since there was no way to repair that at the time, either. snip That is why I suggested sending an expendable rocket with materials to for Columbia crew to make an emergency patch. Titanium sheets and sheets of ablative material and fasteners, for example. But that quite simply would not work for the RCC wing leading edge. The best NASA could do was make a repair kit for the tiles. Again, they didn't know whether it was the leading edge or the exact nature of the damage. The expendable rocket could send up several tons of various materials, using whatever was deemed necessary. Again, they were pretty sure it was NOT the leading edge until after the fact, since no one believed that a foam strike could damage the RCC. They'd done lots of work on what it took to damage the RCC because of concerns about on orbit damage (which they'd seen on various missions), but all that work assumed relatively small impactors at relatively high velocities. Nobody had looked at impacts from large chunks of foam at several hundred miles an hour and when they did look they quickly discovered that such an impact would blow huge holes in the RCC. snip -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
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The Space Race was about Power Projection - Miles O'Brien
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The Space Race was about Power Projection - Miles O'Brien
"Stuf4" wrote in message
... JF: Imagine if you had two cars and had to pull the cylinder head from one and install it on the other when you wanted to use it. Insane, right?" That is called "cannibalization", and a very common practice in high performance aerospace vehicles. Hardly ideal, but a cost-effective approach to maintenance. It's common, but a bad idea. For many reasons, one, simply being every time you touch an item, the odds of making a mistake goes up. Not getting a screw tight enough, forgetting a seal, etc. JF: "the SRBs ought to have been replaced with reusable liquid boosters" A fact that so many people are willing to ignore is that the SRBs performed totally adequately for 24 straight missions. They never failed a single time. So that's 48 SRB successes in a row. 144 field joints did their job. Umm, no, they failed MULTIPLE times. There was hot gasses reaching O-rings on a number of previous flights. Morton-Thiokol and Marshall were spending a LOT of time trying to quantify the reasons, the limits and improvements. Almost every flight had an SRB anomaly . The only time they failed was when NASA decided to launch with temps WAY OUT OF LIMITS. Here is an exact quote from Thiokol's Bob Ebeling: "[W]e're only qualified to 40 degrees ...'what business does anyone even have thinking about 18 degrees, we're in no man's land.'" (https://www.nasaspaceflight.com/2007...of-challenger/) The Ebeling is remembering things wrongly because there was no specific temperature qualification! There was a range of data they were working from. THAT is the one and only proximate cause of the Challenger disaster. No, it's not. ...and the culpability for this fatal error falls not only on NASA top management, nor middle management, but the one level of decision-making that everyone, for whatever reason, chooses to avoid mentioning: - Operations. THEY were the ones whose duty was to know these limits better than anyone else involved in the launch decision. Yet all of them decided to not voice their objections. That goes for the dozens upon dozens of people in Launch Control, the many dozens in Mission Control, and also the crew themselves. Bull****. They had voiced their objections. But they also knew as engineers that NO system is ever perfectly safe. Hell, if anything most them knew better than the big-wigs higher up the food-chain that the shuttle was NOT an operational system and could not be treated as such. At best they could look at the data they were getting (such as burn-throughs and other issues) and try to determine why, what the risk was and if they could solve it. The crew paid for this mistake with their lives. Other people in operations like Gene Thomas, Bob Sieck, Jay Greene, Fred Gregory, etc got *promoted*. That's the most effective way to cover up an egregious error. Everybody pretend that it never happened. That it wasn't their job to stop the launch. It's much easier to blame an inanimate object like O-rings even though they had a track record of a 100% success rate when launched within temp limits. Except reality begs to differ from your "alternative facts". There were issues on almost every single flight. Issues that violated the original design criteria which specified that NO hot gasses were supposed to ever reach the O-Rings. Part of the problem though was that NO one had ever built, let alone FLOWN SRBs that big. After the first flight, the engineers realized their design wasn't working as designed. So they were trying to figure out how and why and what the exact limits of the system were. SRB field joints had a batting average of 1000. 144 successes with 144 at bats. Not a perfect design, to be sure. But it worked when established limits were respected. O-rings are *NOT* what killed Scobee and his crew. It was every person involved in the chain that arrived at the decision that it was a good idea to launch in spite of the freezing cold temps. And it likewise needs to be identified that also culpable for these 7 fatalities is everyone from back in the 1970s who was involved in the decision to not give shuttle crews a viable means of escape. It would have been very easy to have designed the crew cabin as a breakaway structure. Being a pressure vessel, it was already robust. Not much more was needed than a stabilization drogue chute and thermal protection. A set of very light tiles or blankets would have done the trick. From there, all the crews would have needed was pressure suits with parachutes. Sure it would have been simple. And 100% safe because they would have failed to meet their design criteria of payload. Such a simple low cost lightweight low-performance-impact solution would have saved 14 lives. Or if it failed in saving lives, it would have at least given them a fighting chance. Some glimmer of hope for survival. Hardly lightweight. And you'd also have needed pyros to make sure you detached everything (because otherwise one could imagine a situation where say the crew compartment and part of the payload compartment are stuck together and too massive for your parachutes. So next thing you're saying is bigger parachutes. Or other design criteria) And NASA doesn't like to use any more pyros than necessarily. In the case of 51-L, something as simple as a sport parachute might have made the difference between living and dying. This is *half* of what recreational parachutists use on a daily basis. Just give the astronauts the "reserve". But no. They were not even given that much. It would have made zero difference. For one they would not have made it out of the cabin because of the tumbling. For another they would not have made it out of the cabin because they were unconscious. And that assumes NO critical injuries due to the break-up itself. ~ CT -- Greg D. Moore http://greenmountainsoftware.wordpress.com/ CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net |
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The Space Race was about Power Projection - Miles O'Brien
"Jeff Findley" wrote in message
... In article , says... Jeff Findley wrote: Agreed that the system was flawed in that it lacked a crew escape capability on a vehicle that was large, complex, and prone to failure. As for an escape capsule being a viable add-on to the shuttle, I call bull****. And the primary reason that it lacked a crew escape module is because it was impossible to safely and rapidly terminate thrust to the solids to allow such a system to work. Which brings us back to flying human beings on solid boosters is a special kind of stupid. Agreed. And the stupidity continues with SLS with some notable differences. SLS will have a five segment SRB as opposed to the shuttle's four segment SRB (things that are different just aren't the same). And the SLS SRBs will not be reused, so there will be no chance to tear them down and inspect flown SRBs for problems. And THIS is one of the seemingly unlearned lessons of reusability. Even if the mony-savings was a breakeven, the information gained was priceless. Performance uber alles. :-( Jeff -- Greg D. Moore http://greenmountainsoftware.wordpress.com/ CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net |
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