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#51
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Need help with a rocket motor ID
On Sun, 4 Feb 2007 12:28:20 +1030, "Dave Kearton"
wrote: wrote in message .. . On Sat, 03 Feb 2007 02:47:10 GMT, "William R Thompson" wrote: I could go on, but I won't. I am the only person in the world completly happy with both systems, and who thinks they are both equally screwed up. Henry H. We all understand the difficulty of migrating from one system to another. So, don't migrate, use what suits, which is what people do, anyway. At least in the U. S. and to my observation, a lot in Europe, too. I use to be involved with some standards activity. (in ordinary language, you could have said I was a mermber of a ISO working group). Some one once told me that the nice thing about standards was that there were so many everyone could have one of their own. After a while, I concluded that the result of having more standards ws that there were more choices, because the old ones don't go away. So, I went away. Australia's change to metrics started on the 14th Feb '66 with the change to decimal currency - dollars and cents. All Aussies over 45 can still remember the TV jingle. A currency based on multiples of 10 makes more sense than one based on 12s (unless your family tree doesn't branch) The US has had decimal currancy for a while. Once that was achieved, switching to Celsius from Farneheit in the mid '70s wasn't such of a chore. The question of temperature scales (very near and dear to me, a mechanical engineer who is suppose to know about thermodynamics) is really quite seperate from the "Metric" issue. The original Metric system didn't even include temperatrue, as the concept was not really established at that time. In promoting the Centegrade scale, the proponents tried to paint Farneheit as being stupid. Who would make a scale that went from 32 to 212 for Gods sake. Well, he didn't. He had variations as the progresed in his work, but basiclly he intended to go from zero to 96 degrees. The zero he had a bit of trouble standardizing, but he intended it to be the coldest temperature that would be expernced. The 96 was suppose t be avrage human body temperature. (Why 96? A bit of numerology, apprently, but it was at least three times a power of two. A power of two is very handy when you are laying out scales. 100 has no advantage.) The fact that water freezes at about zero is handy, maybe. But you have to use negative numbers for ordinary temperatures. Not good in Farneheit's day. Water boiling is not really very relevant. Neither the freezing point or the boiling point have actually be the definitions of the scale for almost almost as long as the scale has existed. The actual definitions now are that there is only one refernce point and that is zero, absolute. The "Celsius" scale is defined in terms of the "Kelvin" or "degree" to ordinary people. The only difference in that and Farneheit now is that a Farneheit degree is 1/1.8 times the size of a Kelvin. Big deal. What is the boiling point of LOX? Who cares what the scale is? At one point, for a couple of years in the early '80s, as I recall, it was illegal to posess for sale rulers with imperial units on them. It was a ridiculous and draconian measure - but effective in getting some of the older farts to consider using metric units. Ridiculous and draconian measure, I say. The law is a fool, I say. Road signs and speeds followed next, closely followed by weights and measures in general. All up, the conversion for the general public was completed by the mid '80s, I'd imagine it was completed a lot faster in specialist industries. Specialist industries in the US converted any time they wanted to, and many, like the drug industry, have been metric forever. The US had a fit of metrication fever about the same time. It got as for as putting up a few speed limit signs. And "kilometer" posts. When people saw those, the said what the F*** is this, and when they figureed out how much money this was going to cost, most states said "Forget it." That was one of those "unfunded mandates" (that is not the right term, maybe). The Federal government mandated it, but the states were going to have to pay for it. I live near the state of Deleware. They not only have mile posts on their turnpike, they have kilo posts, too. In fact, they have HALF kilo posts! Deleware is so small you can almost see all of them at once. There are about 20 or 30 of them. (I am not really sure about the mile posts. They may have the speed limit signs in mph and kph also. They can if they want to.) One thing that I find quirky with the US metric experience is your parochial spelling of metric units. Whereas the rest of the world has adopted the original spelling of Litre, Metre etc, why does the US prefer to use the 'er spelling ? I don't really remember. That has been going on for at least 150 years. I think it has something to do with the idea that we speak, more or less, English here. And we couldn't pronounce "metre." I think that the US was the first country other than France to adopt the meter/metre. A long time before the British. We just didn't make it mandantory. A few years ago, the inch was redefined so that it is now 2.54 cm, EXACTLY. You just don't have to say it in cm. When that happened, the US shrank by 20 feet. No big deal except to those with beach property. In the metrication exercise, there was one part of it that did "catch on." That was that the BATF (Bureau of Alcohol, tobacco and Firearms) did mandate compulsory metric bottle sizes for all Alcoholic beverages. Of course, they completly screwed it up. Actually, they jsut made brand new metric sizes for the old bottle sizes. So they are metric, but wierd metric. The main size is 750 ml, which is very close to the old 4/5 US quart size (746 ml, IIRC). Not worth the effort. "Twice" that is not 1.5 l., as you might suppose, but accordign to the BATF is 1.75 l. Beats me. Just makes it hard to compare prices. The people who squeeled the loudest? The French wine industry, who not only had to change bottle sizes, they had to have STANDARD sizes. 200 years and there was not a standard size for wine bottles! The French said that was because the wine bottle was a standard in its self, the perfect size for two people to consume at a meal! Known to them, even if not to you. There are several "funny" thing about the liter/litre. It has driven the SI guys, who have a lot of time on thier hands, in to various fits of stupid. It is not as simple as I once thought, but the liter got "double defined" like a lot of other stuff in the orginal metric system. The kilometer was the orignal "base" unit, and was 1/40000 the Earths circumference, (Paris meridian, of course. ) Before they even got the survey done, the scratched lines on a bar for a "practical standard". Of course, those don't agree, and on, and on. The kilogram was based on the weight (or mass, take your pick) of 1/1000 of a cubic meter. The liter was either 1/1000 o f a cubic meter or the volume of one kilogram of water, it fluctuated. And, those were not the same, of course. Just a few years ago, the SI banned the liter entirely. No matter how you spelled I think maybe it was out for 6 years. Then they let it back in, with the cobic meter definition. The other oddity of the liter/liter is that the SI says you cannot abreviate it except as "l.". Even though that is very confusing to read often. "L." is not allowed because capitals are resereved for units that are named for people. Some genius tried to fix that by submitting a bio of Andre Litre, the great physicist who was a the son of a wine merchant. The Si woudn't by it. No sense of humor. After haveing been following measurement issues for about 100 years, I got a big surprise lately when I discovred the explanation for the size of the US gallon. I always thought it was just dumb. 231 cubic inches. I had read somewere that the people responsible for the British standars at one time just happened to have a nice cup that size. Not so. In Queen Anne's day, there were several gallons, various sizes, used for various things in various parts of Britian. So , Queen Anne, or her agents, decided to have a new standard, so that there would be one more gallon, "Queen Anne's Wine Gallon." In order to demonstrate their scientific talents they defined that as exactly the volume of a cylinder seven inches in diameter and six inches hight. They picked those numbers because using them, you get an exact whole number for the volume. 231 cubic inches! They also defined the gallon as just that, 231 cubic inches. Problem was, those are only the same on days when pi is equal to 22/7. Most days, pi is closer to 355/113/ That is a differnence of 0.1 cubic incehs, or something. OH, well. Later, after we ran them off, the British tried to catch up with the French by defining yet another gallon, This one equal in volume to 10 pounds of water, at some conditions. Well, happy metrication, and have a good 1/365.24 of a mean solar year. Henry H. |
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Need help with a rocket motor ID
wrote in message
... On Sun, 4 Feb 2007 12:28:20 +1030, "Dave Kearton" wrote: Well, happy metrication, and have a good 1/365.24 of a mean solar year. Henry H. If you can fill the unforgiving minute With sixty seconds' worth of distance run, Yours is the Earth and everything that's in it, And--which is more--you'll be a Man, my son! - Rudmetre Kipling (1865-1936) -- Cheers Dave Kearton |
#53
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Need help with a rocket motor ID
wrote in message
... On Sun, 4 Feb 2007 12:28:20 +1030, "Dave Kearton" wrote: Well, happy metrication, and have a good 1/365.24 of a mean solar year. Henry H. If you can fill the unforgiving minute With sixty seconds' worth of distance run, Yours is the Earth and everything that's in it, And--which is more--you'll be a Man, my son! - Rudmetre Kipling (1865-1936) -- Cheers Dave Kearton |
#54
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Need help with a rocket motor ID
On 3 Feb 2007 00:12:02 -0600, jc wrote:
On Fri, 2 Feb 2007 18:38:32 +1030, "Dave Kearton" wrote: [snip] The other thing is the way the fluid lines wrap around the can looks like preheat to me. That either means a fuel that doesn't vaporize easily, like kerosene, or a cold soaked environment. That goes along with the idea that it's designed for vacuum. Well, yes. It does preheat the propellant. But that is not the main idea, or usually isn't. Almost all liquid propellant rockets are "regen" cooled. That keeps them from melting down and burning through. All your usual engines are like thta. Atlas, Delta, F-1, SSME, etc. American LOX/RP engines use RP cooling. the temp rise is fairly small, doesn't have much effect on combustion. Note that the engine has to start so it has to run on "cold" propellant. It is a bit different with LOX/LH2 engines. In fact, AFAIK, there are NO "LH2" engines. The hydrogen picks up enough heat in the jacket so that it enters the combustion chamber as a gas. One of those engines, the P&W RL-10, the Centaur engine runs the H2 thru a turbine which drives the turbo pump. They call it the "expander cycle." At one time, there was a great series of studies of new engine designs, and P&W was pushing "their" expander cycle. One of the advantages they claimed was that the expander cycle has "graceful degradation." Say you get a hot sopt in the jacket and it starts to burn through (just the inner wall). That cuts the flow to the trubine which reduces the heat flux and stops the burn through. That sounded good. As as vehicle design team participant in the study, I backed them all I could. For my own vested interests. It turned out that P&W could find no other mode that the expander was more graceful at than the competing "GG" cycle, And, the GG cycle was not at all prone to burn thru. So it was something like a protection agains a problem that you were causing. P&W and I gracefully degraded, together. Henry H. [snip] |
#55
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Need help with a rocket motor ID
On 3 Feb 2007 00:12:02 -0600, jc wrote:
On Fri, 2 Feb 2007 18:38:32 +1030, "Dave Kearton" wrote: [snip] The other thing is the way the fluid lines wrap around the can looks like preheat to me. That either means a fuel that doesn't vaporize easily, like kerosene, or a cold soaked environment. That goes along with the idea that it's designed for vacuum. Well, yes. It does preheat the propellant. But that is not the main idea, or usually isn't. Almost all liquid propellant rockets are "regen" cooled. That keeps them from melting down and burning through. All your usual engines are like thta. Atlas, Delta, F-1, SSME, etc. American LOX/RP engines use RP cooling. the temp rise is fairly small, doesn't have much effect on combustion. Note that the engine has to start so it has to run on "cold" propellant. It is a bit different with LOX/LH2 engines. In fact, AFAIK, there are NO "LH2" engines. The hydrogen picks up enough heat in the jacket so that it enters the combustion chamber as a gas. One of those engines, the P&W RL-10, the Centaur engine runs the H2 thru a turbine which drives the turbo pump. They call it the "expander cycle." At one time, there was a great series of studies of new engine designs, and P&W was pushing "their" expander cycle. One of the advantages they claimed was that the expander cycle has "graceful degradation." Say you get a hot sopt in the jacket and it starts to burn through (just the inner wall). That cuts the flow to the trubine which reduces the heat flux and stops the burn through. That sounded good. As as vehicle design team participant in the study, I backed them all I could. For my own vested interests. It turned out that P&W could find no other mode that the expander was more graceful at than the competing "GG" cycle, And, the GG cycle was not at all prone to burn thru. So it was something like a protection agains a problem that you were causing. P&W and I gracefully degraded, together. Henry H. [snip] |
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Need help with a rocket motor ID
On Sun, 04 Feb 2007 03:40:31 GMT, "William R Thompson"
wrote: Henry_H@Q_wrote: I see that there was a lot of discussion I didn't read. I am glad to see that the source was tracked down. But, I am I bit surprised to see it was from Rocketdyne. It looks like someone issued specs that said, basically, "make it reliable and simple, and don't worry too much about the weight." As I said, it doesn't look like it goes to far "up the stack". I though about it being an "airplane" but I couldn't imagine which one. But, it looks better, "all dressed up." (For airplanes, RATO lost out to the army developed "JATO" solid propellant "boosters.") I can see why. RATO could be throttled and restarted, but I think the only application anyone saw for that was in seaplane take-offs. JATO looks a lot less maintenance-intense than RATO (see attached picture). Hey, looks simple to me! I have done my tour on both the liquid and solid fronts. Both have advantages, both have problems. I will take the liquid problems any day. But, I am in the minority it seems. I think it turns out that rockets are much to expensive for general use whether they are liguid or solid. I meant to say that although Truax didn't have the right answer for airplanes, that work lead drrectly on to the whole world of hypergols in the US, many, many vehicles and engine/motors. T-Stoff, was a mixture of 80% hydrogen peroxide plus oxyquinoline or phosphate as a stabilizer. [most of the other 20 percent would have been water. _hh] And that C-Stoff was a mixture of 57% methanol + 30% hydrazine hydrate + 13% water, with traces of either cupro-potassium cyanide or copper oxide (probably as a stabilizer). I accept those as being correct. Methanol the kind of stuff you would want as a fuel. The hydrazine hydrate would be added to provide "smooth combustion" and the water may have resulted from using the highest concentration of hydrazine hydrate that was available, or possibly it was just added as coolant. (Usually wiki is a really good place for this kind of stuff, but I didn't find the exact numbers there) Those are the same figures in Sutton's "Rocket Propulsion Elements." I figure that Mano Zeigler gave different numbers in "Rocket Fighter" due to conditions in Axisland--with the Allies bombing their plants and supply lines, they may have had to settle for anything that could flow through the lines and burn. If I remember the book, and I am pretty sure I do, it was sort of a "quick and dirty" account based on very limited sources. I think I first read it myself only a couple of years after the war, so it has been around a while. A lot of documentation dhowed up later that the author didn't have then. It is hard to find people in the rocket biz that have had long term exposure to hydrazine that have not also be exposed to N2O4 so when there are stories about long term effects, you don't know which to blame. But I will take the alternative to "in a couple of more days, they die." Better chronic than prompt. As I recall, Vance Brand passed out from exposure to dumped fuels during the Apollo-18/ASTP descent, and the crew was taken to the hospital afterward. They didn't seem to suffer any long-term effects. I remember somethign about tat, but I don't even know as much as you said. (In ordnance circles, I got into this thing of distinguishing between "high order" explosions or "detonations" and "low order" explosions or deflagrations. Then there are "no yield" ones, like tank ruptures. I use to rankle when people talked about auto gas tanks exploding, or example. Then I read some dictionaries. The "sufficient" definition of an "explosion" seems to be some event in which a noise was heard.) I know people who think that a proper footnote is anything with an asterisk. (Sorry, but citing a newspaper gossip column isn't quite the same as citing, say, a trial transcript.) One thing that was more hazardous on the Me163 than the exotic (for then) propellants was the operational scenario. Take off, climb to combat altitude, run out of propellant, glide to a landing spot, and be stuck on the ground on the landing skids. The allied pilots quickly figured that out, and that there was little to be done about powered flight, so they just waited and followed them down and nailed them on the ground. It is a wonder that anyone had any stories about explosions, they should have all been killed. My conclusion from trying to find out what happened was that the Luffwaffe was totally negligent in keeping any useful accident reports in the WW II era, at least that I found. That was a typical condition in the Reich. And, given how hard it was to find self-confessed Nazis after the war, the condition persisted. Albert Speer's "Inside the Third Reich" is a classic example. You have to be careful about testimony of participants. You have to be ten times more careful when they are under duress. And, being a POW after having lost a war is a LOT of duress. But there are all to many examples of people thinking up stories and then feeding them to people just like that to get them to play them back. The worst one I think of off hand was some guy who was on the interrogation team of the Japanese Navy participants in PH. His own personal theory was that the Japanese should have left the ships alone and gone for the oil tanks. So he asked that question over and over again until all the Japanese got the answer right. There was a similar deal about the pre war demands, whch are totally unclear as to whether they mean "China" or IndoChina" or both. Some different guy (I guess he was different) got all sorts of people to say it would have been entirely different, "If they had only known" what we said. The Japanese were unusually eager to cooperate, be everyone is eager in those circumstances. Designers are often told that "You have to listen to what the user says, they were the ones that know what is going on. I agree that you should listen. But you should evaluate what you hear. Anyone's "eye witness account" is likely to be highly biased and frequently just imaginary. That's what I was taught when getting my degrees in hysteria, er, history. My favorite example has to do with the "Nuts!" event at Bastogne. There are several accounts of exactly what was said; the accounts come from people who were there--and they don't match up. I have read many of those accounts. And there are very different versions of what General McAuliffe initally said. Some say it was profane, othere say that people heard what they wanted to hear, and that McAuliffe never used profanity and that is exactly what he would have said. "It is very true, and if it is not, it should be." Some stories are so well known and are so much a paart of what happened they are as important as "facts." But, there is another aspect of the "Nuts" story. In about 1950 the National Archives put togetner an exibition on a train and it toured the country. It had really "heavy weight" stuff on it. Including the Constitution and the Declaration of Independnce, the originals (I think!). Hard to imagine doing that now. I toured the train. I was there. I SAW the piece of paper that McAuliffe wrote it on. Just like the Germans to file that away. SO, although there can be debate about what he SAID, I KNOW what he wrote, because I saw it. However, I can't find any discussionof anyone else knowing that. (Although the military historian SLA Marshall claims that the Germans did, indeed, get the "Nuts!" message. Marshall interrogated Manteuffel and his staff after the war. At one session Manteuffel kept blaming his mistakes on his staff. At last one of his subordinates leaned forward, waggled a finger in Manteuffel's face and shouted "Nuts! Nuts!") Another sub plot to that story that I have seen in one account was that there was some junior officere there who was an English language expert. He thought up the idea of the surrender demand. And wrote it and got permission to deliver it. But, when he got the answer, he didn't know what it meant. The officer who escorted him back to the German lines explained it in terms the German understood. He may have used any of the expressins that have been suggested. It was also said that when they parted, the German made a last plea "you must accept or many people will die." the escort was said to have said "this is war and that is what it is all about. Many will die and they won't all be on our side." Now, that is a REAL fairy tale. And, what were the seals and all the other bits made of. I was once reading a report on the X-1 which was very like an American Lox Me163 and at about the same time. There was something about an explosion and a fire. The report said they weren't sure what happened, but they though it might have involved a seal. (I think maybe it was in a check valve and lit off when the valve closure slammed on it.) They then started to discuss what sort of special, proprietary LEATHER (!) the seal was made of. I quit reading. The Ulmer leather gaskets, which if memory serves were treated with tricresyl phosphate. The accounts I've read said that the treated gaskets didn't react with the liquid oxygen--but in the presence of lox, the gaskets became *very* sensitive to mechanical shock, making them "slightly" explosive. I think the losses of the X-1A, X-1D and second X-2 were blamed on that. I have though about that a lot. The correct process for making leather LOX compatable doesn't leave ANY leather in the leather. Or as I told a guy once "Send me that (polyethelyne bottle) to be LOX cleaned and I will send you back an empty bag with a tag on it." In those days, I gather, they hadn't come up with impact testing. And such events were how they got the idea. In one sense, most things are "compatible" with LOX, as there is no "attack' in the absece of impact. RP won't react with LOX until you hit or subect it to an ignition source. That is what makes it so dangerous, you can get an accumulationt that will blow the back end of the vehicle into the next county. "Static" compatibility is meaningless for LOX. "Low order" reactions to impact are also pretty meaningless since even a small pop can do a lot of damage, including possibly stuff like igniting some surrounding stuff, like aluminum valve housings, say. It is somewhat hard to see how anything could have been done wiht any useful oxidizer, LOX, peroxide, N2O4 or whatever, untel Teflon came along. But they did do lots of stuff. Even Teflon has a lot of problems. (but is compatable.) Henry H. --Bill Thompson |
#57
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Need help with a rocket motor ID
On Sun, 04 Feb 2007 03:40:31 GMT, "William R Thompson"
wrote: Henry_H@Q_wrote: I see that there was a lot of discussion I didn't read. I am glad to see that the source was tracked down. But, I am I bit surprised to see it was from Rocketdyne. It looks like someone issued specs that said, basically, "make it reliable and simple, and don't worry too much about the weight." As I said, it doesn't look like it goes to far "up the stack". I though about it being an "airplane" but I couldn't imagine which one. But, it looks better, "all dressed up." (For airplanes, RATO lost out to the army developed "JATO" solid propellant "boosters.") I can see why. RATO could be throttled and restarted, but I think the only application anyone saw for that was in seaplane take-offs. JATO looks a lot less maintenance-intense than RATO (see attached picture). Hey, looks simple to me! I have done my tour on both the liquid and solid fronts. Both have advantages, both have problems. I will take the liquid problems any day. But, I am in the minority it seems. I think it turns out that rockets are much to expensive for general use whether they are liguid or solid. I meant to say that although Truax didn't have the right answer for airplanes, that work lead drrectly on to the whole world of hypergols in the US, many, many vehicles and engine/motors. T-Stoff, was a mixture of 80% hydrogen peroxide plus oxyquinoline or phosphate as a stabilizer. [most of the other 20 percent would have been water. _hh] And that C-Stoff was a mixture of 57% methanol + 30% hydrazine hydrate + 13% water, with traces of either cupro-potassium cyanide or copper oxide (probably as a stabilizer). I accept those as being correct. Methanol the kind of stuff you would want as a fuel. The hydrazine hydrate would be added to provide "smooth combustion" and the water may have resulted from using the highest concentration of hydrazine hydrate that was available, or possibly it was just added as coolant. (Usually wiki is a really good place for this kind of stuff, but I didn't find the exact numbers there) Those are the same figures in Sutton's "Rocket Propulsion Elements." I figure that Mano Zeigler gave different numbers in "Rocket Fighter" due to conditions in Axisland--with the Allies bombing their plants and supply lines, they may have had to settle for anything that could flow through the lines and burn. If I remember the book, and I am pretty sure I do, it was sort of a "quick and dirty" account based on very limited sources. I think I first read it myself only a couple of years after the war, so it has been around a while. A lot of documentation dhowed up later that the author didn't have then. It is hard to find people in the rocket biz that have had long term exposure to hydrazine that have not also be exposed to N2O4 so when there are stories about long term effects, you don't know which to blame. But I will take the alternative to "in a couple of more days, they die." Better chronic than prompt. As I recall, Vance Brand passed out from exposure to dumped fuels during the Apollo-18/ASTP descent, and the crew was taken to the hospital afterward. They didn't seem to suffer any long-term effects. I remember somethign about tat, but I don't even know as much as you said. (In ordnance circles, I got into this thing of distinguishing between "high order" explosions or "detonations" and "low order" explosions or deflagrations. Then there are "no yield" ones, like tank ruptures. I use to rankle when people talked about auto gas tanks exploding, or example. Then I read some dictionaries. The "sufficient" definition of an "explosion" seems to be some event in which a noise was heard.) I know people who think that a proper footnote is anything with an asterisk. (Sorry, but citing a newspaper gossip column isn't quite the same as citing, say, a trial transcript.) One thing that was more hazardous on the Me163 than the exotic (for then) propellants was the operational scenario. Take off, climb to combat altitude, run out of propellant, glide to a landing spot, and be stuck on the ground on the landing skids. The allied pilots quickly figured that out, and that there was little to be done about powered flight, so they just waited and followed them down and nailed them on the ground. It is a wonder that anyone had any stories about explosions, they should have all been killed. My conclusion from trying to find out what happened was that the Luffwaffe was totally negligent in keeping any useful accident reports in the WW II era, at least that I found. That was a typical condition in the Reich. And, given how hard it was to find self-confessed Nazis after the war, the condition persisted. Albert Speer's "Inside the Third Reich" is a classic example. You have to be careful about testimony of participants. You have to be ten times more careful when they are under duress. And, being a POW after having lost a war is a LOT of duress. But there are all to many examples of people thinking up stories and then feeding them to people just like that to get them to play them back. The worst one I think of off hand was some guy who was on the interrogation team of the Japanese Navy participants in PH. His own personal theory was that the Japanese should have left the ships alone and gone for the oil tanks. So he asked that question over and over again until all the Japanese got the answer right. There was a similar deal about the pre war demands, whch are totally unclear as to whether they mean "China" or IndoChina" or both. Some different guy (I guess he was different) got all sorts of people to say it would have been entirely different, "If they had only known" what we said. The Japanese were unusually eager to cooperate, be everyone is eager in those circumstances. Designers are often told that "You have to listen to what the user says, they were the ones that know what is going on. I agree that you should listen. But you should evaluate what you hear. Anyone's "eye witness account" is likely to be highly biased and frequently just imaginary. That's what I was taught when getting my degrees in hysteria, er, history. My favorite example has to do with the "Nuts!" event at Bastogne. There are several accounts of exactly what was said; the accounts come from people who were there--and they don't match up. I have read many of those accounts. And there are very different versions of what General McAuliffe initally said. Some say it was profane, othere say that people heard what they wanted to hear, and that McAuliffe never used profanity and that is exactly what he would have said. "It is very true, and if it is not, it should be." Some stories are so well known and are so much a paart of what happened they are as important as "facts." But, there is another aspect of the "Nuts" story. In about 1950 the National Archives put togetner an exibition on a train and it toured the country. It had really "heavy weight" stuff on it. Including the Constitution and the Declaration of Independnce, the originals (I think!). Hard to imagine doing that now. I toured the train. I was there. I SAW the piece of paper that McAuliffe wrote it on. Just like the Germans to file that away. SO, although there can be debate about what he SAID, I KNOW what he wrote, because I saw it. However, I can't find any discussionof anyone else knowing that. (Although the military historian SLA Marshall claims that the Germans did, indeed, get the "Nuts!" message. Marshall interrogated Manteuffel and his staff after the war. At one session Manteuffel kept blaming his mistakes on his staff. At last one of his subordinates leaned forward, waggled a finger in Manteuffel's face and shouted "Nuts! Nuts!") Another sub plot to that story that I have seen in one account was that there was some junior officere there who was an English language expert. He thought up the idea of the surrender demand. And wrote it and got permission to deliver it. But, when he got the answer, he didn't know what it meant. The officer who escorted him back to the German lines explained it in terms the German understood. He may have used any of the expressins that have been suggested. It was also said that when they parted, the German made a last plea "you must accept or many people will die." the escort was said to have said "this is war and that is what it is all about. Many will die and they won't all be on our side." Now, that is a REAL fairy tale. And, what were the seals and all the other bits made of. I was once reading a report on the X-1 which was very like an American Lox Me163 and at about the same time. There was something about an explosion and a fire. The report said they weren't sure what happened, but they though it might have involved a seal. (I think maybe it was in a check valve and lit off when the valve closure slammed on it.) They then started to discuss what sort of special, proprietary LEATHER (!) the seal was made of. I quit reading. The Ulmer leather gaskets, which if memory serves were treated with tricresyl phosphate. The accounts I've read said that the treated gaskets didn't react with the liquid oxygen--but in the presence of lox, the gaskets became *very* sensitive to mechanical shock, making them "slightly" explosive. I think the losses of the X-1A, X-1D and second X-2 were blamed on that. I have though about that a lot. The correct process for making leather LOX compatable doesn't leave ANY leather in the leather. Or as I told a guy once "Send me that (polyethelyne bottle) to be LOX cleaned and I will send you back an empty bag with a tag on it." In those days, I gather, they hadn't come up with impact testing. And such events were how they got the idea. In one sense, most things are "compatible" with LOX, as there is no "attack' in the absece of impact. RP won't react with LOX until you hit or subect it to an ignition source. That is what makes it so dangerous, you can get an accumulationt that will blow the back end of the vehicle into the next county. "Static" compatibility is meaningless for LOX. "Low order" reactions to impact are also pretty meaningless since even a small pop can do a lot of damage, including possibly stuff like igniting some surrounding stuff, like aluminum valve housings, say. It is somewhat hard to see how anything could have been done wiht any useful oxidizer, LOX, peroxide, N2O4 or whatever, untel Teflon came along. But they did do lots of stuff. Even Teflon has a lot of problems. (but is compatable.) Henry H. --Bill Thompson |
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Need help with a rocket motor ID
On Sun, 04 Feb 2007 03:40:31 GMT, "William R Thompson"
wrote: [snip] That's what I was taught when getting my degrees in hysteria, er, history. My favorite example has to do with the "Nuts!" event at Bastogne. There are several accounts of exactly what was said; the accounts come from people who were there--and they don't match up. After my first reply to this message I did some Googleing. I still can't find any mention of the "Nuts" document. However, I did find this on wiki: ***************** The 1947-1949 Freedom Train was proposed by Attorney General Tom C. Clark as a way to reawaken Americans to their taken-for-granted principles of liberty in the post-war years. The idea soon got the approval of President Harry S. Truman and everything else fell into place. Top Marines were selected to attend to the train and its famous documents. The Marine contingent was led by Col. Robert F. Scott. The train carried the original versions of the United States Constitution, Declaration of Independence and the Bill of Rights on its tour of more than 300 cities in all 48 states. As Alaska and Hawaii didn't gain statehood until 1959, this train toured all of the US States that existed at the time. ***************** I saw it when it stopped in Atlanta, Ga. on Jan. 2, 1948/ I am very sceptical of authority in reference sources, I certainly don't think the EB is very authorative. "Trust everyone, but cut the cards, anyway." But, as a friend use to say "Even a blind pig finds some nuts." There are a LOT of nuts on wiki. Various kinds. No matter what you know, you don't know that you know everything until you check wiki. Henry H. |
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Need help with a rocket motor ID
On Sun, 04 Feb 2007 03:40:31 GMT, "William R Thompson"
wrote: [snip] That's what I was taught when getting my degrees in hysteria, er, history. My favorite example has to do with the "Nuts!" event at Bastogne. There are several accounts of exactly what was said; the accounts come from people who were there--and they don't match up. After my first reply to this message I did some Googleing. I still can't find any mention of the "Nuts" document. However, I did find this on wiki: ***************** The 1947-1949 Freedom Train was proposed by Attorney General Tom C. Clark as a way to reawaken Americans to their taken-for-granted principles of liberty in the post-war years. The idea soon got the approval of President Harry S. Truman and everything else fell into place. Top Marines were selected to attend to the train and its famous documents. The Marine contingent was led by Col. Robert F. Scott. The train carried the original versions of the United States Constitution, Declaration of Independence and the Bill of Rights on its tour of more than 300 cities in all 48 states. As Alaska and Hawaii didn't gain statehood until 1959, this train toured all of the US States that existed at the time. ***************** I saw it when it stopped in Atlanta, Ga. on Jan. 2, 1948/ I am very sceptical of authority in reference sources, I certainly don't think the EB is very authorative. "Trust everyone, but cut the cards, anyway." But, as a friend use to say "Even a blind pig finds some nuts." There are a LOT of nuts on wiki. Various kinds. No matter what you know, you don't know that you know everything until you check wiki. Henry H. |
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Need help with a rocket motor ID
Henry_H@Q wrote:
"William R Thompson" wrote: [snip] That's what I was taught when getting my degrees in hysteria, er, history. My favorite example has to do with the "Nuts!" event at Bastogne. There are several accounts of exactly what was said; the accounts come from people who were there--and they don't match up. After my first reply to this message I did some Googleing. I still can't find any mention of the "Nuts" document. However, I did find this on wiki: The 1947-1949 Freedom Train was proposed by Attorney General Tom C. Clark as a way to reawaken Americans to their taken-for-granted principles of liberty in the post-war years. The idea soon got the approval of President Harry S. Truman and everything else fell into place. Top Marines were selected to attend to the train and its famous documents. The Marine contingent was led by Col. Robert F. Scott. Well-armed and alert, I trust. The Liberty Bell had been sent on an earlier tour (in the Twenties, I think--details escape me) during which tour bits and pieces were hacked off the rim as souvenirs. I am very sceptical of authority in reference sources, I certainly don't think the EB is very authorative. "Trust everyone, but cut the cards, anyway." The history department's attitude was "multiple references, please, and even then we may laugh." But, as a friend use to say "Even a blind pig finds some nuts." There are a LOT of nuts on wiki. Both metric and SAE. --Bill Thompson |
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