ApolloHoax.net
Apollo Discussions => The Hoax Theory => Topic started by: inconceivable on March 26, 2013, 07:24:11 PM
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Some of the wiring during the 1960's was banned by the Air Force and the Navy. Some have very low temp ratings for space travel. Did NASA create their own wiring and sheathing protection. PVC/Nylon rated to 221F, kynar 302F and Kapton which was one of the most dangerous wires of the time rated at 392F. Is Kapton the wire used for Apollo? Could the wiring or the sheathing have survived in the extreme temperatures of space or even on the moon?
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Some of the wiring during the 1960's was banned by the Air Force and the Navy.
Can you please be more specific about this? It would be helpful if you cited the type of wiring, it's reason for "banning", and the USAF /USN documents detailing the "banning".
Is Kapton the wire used for Apollo?
Kapton is not a wire, it is an insulator used for wiring. http://en.wikipedia.org/wiki/Kapton (http://en.wikipedia.org/wiki/Kapton)
Kapton which was one of the most dangerous wires of the time rated at 392F.
Kapton is not a wire, and according to Wikipedia, it can remain stable in a range temperature from −273 to +400 °C (−459 – 752 °F / 0 – 673 K). Do you have any information that contradicts this, if so can you share it with us?
Could the wiring or the sheathing have survived in the extreme temperatures of space or even on the moon?
None of the wiring, electronics etc would not be directly exposed to the vacuum or sunlight and would be enclosed in shielded, insulated bodies that would have their own temperature regulation systems. See my post below for more detailed information.
The temperature of space is approximately 3K, and so the sheathing would certainly be able to withstand that, but as I said above it would not be exposed directly.
The Apollo CSM had a number of methods of thermal control, the most interesting in my opinion, being Passive Thermal Control (PTC) also known as "barbeque mode" -- a very slow rotation (one revolution per ten minutes or slower) about the spacecraft roll axis and with the desired roll axis direction fixed in space.
Also, don't you think these questions would be better placed in The Reality of Apollo section?
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Whilst looking around for more information on thermal control of Apollo spacecraft, I came across an excellent answer on Yahoo Answers by a gentleman called Clavius who I presume to be a certain JayUtah, which I'll reproduce for you, as his explanation is far better than anything I could muster:
How was the Apollo Lunar Module temperature maintained while on the moon? (in layman's terms, please)?
Insulation combined with reflective coatings.
You have to consider what the sources of heat are: solar influx, metabolic heat from the astronauts, and heat from the electrical equipment. Managing those isn't difficult.
Solar influx is controlled by coating the spacecraft in various places with different materials. The descent stage was not pressurized or inhabited, but contained equipment that had to be kept within certain temperature ranges. So the outer skin was made of aluminized Mylar and Kapton. That reflects 40-60% of the sunlight it receives. So comparatively little of the sun's energy is absorbed. Some parts were covered in a more black film that absorbed more sun.
The ascent stage was covered in aluminum that was painted, etched, or anodized to give each panel precise absorptive properties. The ascent engine fuel likes to be kept at about room temperature, so the bulbous tank enclosures had a reasonable fraction of black panels. The electronics bay was in the back and subjected to the full brunt of the rising sun. Its panels are therefore quite brightly colored to reflect away most of that. The crew cabin was on the shady side and so simply didn't get much sun.
So much for solar heating. The metabolic heat of the astronauts is carried away by the cabin air or by the suit circuit (if they happened to be in their space suits and hooked up to the spaceship's environmental circuit). The heated cabin air is cooled by passing it through a heat-exchanger circulating a water-glycol coolant. The heat transfers to the coolant and cool air comes out the other side. This is largely how any air conditioner works.
There is a special emergency method of cooling the suits where you supply the oxygen at "high flow" rate. The oxygen is kept as a liquid in the suits and in the LM's cryo tank. Naturally as it boils off into a gas to be used for breathing, it's still relatively cold. It's often heated prior to being used in the suit. But at low-flow rate it doesn't trickle into the suit fast enough to chill the astronaut. But at high-flow rate, there is a faster stream of cold oxygen than can be used to cool astronauts in their space suits if any of the other cooling mechanisms fail, but at the cost of more rapid oxygen consumption.
The electronics are mostly mounted outside the habitable volume of the LM, in the back. The temperature-critical components are mounted on rails called coldplates (often called water-blocks today). These are solid metal heat sinks that carry the heat away from each component. More of that same water-glycol mixture circulates through passages in the coldplates carrying away their heat.
So what happens to all the heat in the water-glycol coolant? The coolant passes through a gadget called a sublimator, which is kept in the shade. The sublimator allows water to seep very slowly into the vacuum environment through porous plates, and form an ice cake on the outside. It doesn't flash away as ice or vapor if it is let out into space very slowly. The coolant goes through passages in the sublimator that transfer the heat into the ice. The ice sublimes (converts directly from solid to gaseous water) under that heat load. That phase change from solid to gas takes a measured amount of heat (the "heat of sublimation") to accomplish, and cools the coolant by that amount. Sublimed ice is replaced by more water from below.
Naturally such a system is limited by how much liquid water you have on hand. When you run out of water, you run out of cooling capacity by the sublimator method.
Some electronics were cooled directly to space by radiators. The antenna assemblies and other gadgets on the roof of the LM had sensor and motor assemblies that were cooled by direct radiation.
Taken from here:
http://answers.yahoo.com/question/index?qid=20081006022021AABwsaD (http://answers.yahoo.com/question/index?qid=20081006022021AABwsaD)
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Kapton which was one of the most dangerous wires of the time rated at 392F.
Kapton is not a wire, and according to Wikipedia, it can remain stable in a range temperature from −273 to +400 °C (−459 – 752 °F / 0 – 673 K). Do you have any information that contradicts this, if so can you share it with us?
I think the OP is referring to Kapton insulation being dangerous because it has been found culpable as a root cause of numerous fatal aircraft electrical fires, including the deaths in 1980 of 300 passengers in a Saudia Airflines Lockheed L1011, and the 1998 Swissair Flight 111 crash over Nova Scotia.
Kapton has very poor resistance to abrasion within cable harnesses and tends to wear more easily that other insulation (such as PTFE) due movement while the aircraft is in flight. Literally thousands of airliners have had to undergo extensive rewiring to replace Kapton-insulated wiring due to the risk of short circuits and fires caused by abrasion.
The BBC's Panorama series did a programme about it call "Die by Wire"
http://www.iasa.com.au/folders/Safety_Issues/Aircraft_Wire/panorama.html
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Is Kapton the wire used for Apollo? Could the wiring or the sheathing have survived in the extreme temperatures of space or even on the moon?
Are you really intending to ask if all space flight is fake, because the wiring isn't up to snuff?
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Sure, but that's a wear issue, ain't it? I am not an engineer, but would Apollo missions last long enough that such wear would be an issue, especially since most of the flight would in in freefall?
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Sure, but that's a wear issue, ain't it? I am not an engineer, but would Apollo missions last long enough that such wear would be an issue, especially since most of the flight would in in freefall?
Sure, I agree. There wouldn't be enough time for the wear to take place.
I was just pointing out that the OP was talking about Kapton being "one of the most dangerous wires of the time" without bothering to actually say why it was dangerous.
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Sure, I agree. There wouldn't be enough time for the wear to take place.
I was just pointing out that the OP was talking about Kapton being "one of the most dangerous wires of the time" without bothering to actually say why it was dangerous.
I thought so, thanks.
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Following experience with the results of fires caused by hits in action off the Falklands the RN changed the wiring spec on it's ships in the 80s. They removed miles of cables from ships already in service and changed the spec of cables for new ships. As well as giving off toxic fumes when burnig or heated conducted heat through bulkheads and decks damaged existing cables in adjacent compartments.
But, as above, this isn't something that was too much of a worry on Apollo, I don't think anyone was firing missiles at them.
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What is you question Inconceivable? this thread's title is "would the wiring left on the moon be functional"... is that as in would it STILL be functional after being left on the moon these 40 odd years?...or as in your first post " Could the wiring or the sheathing have survived in the extreme temperatures of space or even on the moon?"
If its the first question...why? are you planning a salvage operation? ;D.. sorry couldn't resist that!.... if it IS the first question, what factors would there be to degrade the wiring?
If it is, as I suspect, the 2nd question.....well obviously YES it could and it did! They went, they landed, they minced around a bit on the surface, they came home? next?.... move along nothing more to see here methinks!
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There is a special emergency method of cooling the suits where you supply the oxygen at "high flow" rate. The oxygen is kept as a liquid in the suits and in the LM's cryo tank. Naturally as it boils off into a gas to be used for breathing, it's still relatively cold. It's often heated prior to being used in the suit.
This is actually incorrect, only the SM had cold oxygen storage. All oxygen in the LM, PLSS and OPS was stored as a pressurized, ambient temperature gas. Only the supercritical helium tank in the DPS was kept cold.
The special high-flow cooling system Jay alludes to here is the OPS - Oxygen Purge System - a backup to the PLSS. The PLSS was like a diving rebreather while the OPS was like SCUBA.
As a "once through" system, the OPS is far simpler than the PLSS but consumed oxygen far more quickly. This was necessary not only to get rid of CO2 and humidity without LiOH, but also to remove metabolic heat from a very well insulated suit. When the OPS had to be used, the astronaut pulled the "red apple" on the lower right side of his torso and opened the purge valve to allow oxygen to vent out of his suit at a controlled rate.
As the O2 expanded out of the OPS tank, it would cool adiabatically. Early versions of the OPS warmed the expanded gas electrically to avoid possible regulator freezing. This was eventually removed as unnecessary. This probably helped cool the astronaut, but I don't know how much.
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Following experience with the results of fires caused by hits in action off the Falklands the RN changed the wiring spec on it's ships in the 80s. They removed miles of cables from ships already in service and changed the spec of cables for new ships. As well as giving off toxic fumes when burnig or heated conducted heat through bulkheads and decks damaged existing cables in adjacent compartments.
I don't think Kapton gives off unusually dangerous fumes...that's more a problem of stuff like PVC insulation. Kapton itself is pretty hard to burn and shouldn't be much worse than anything else that burns, the problem was poor abrasion resistance leading to shorts that set other stuff on fire.
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Kapton has good performance as an electrical insulator because a thinner layer provides suitable electrical protection. That means for large wiring harnesses, considerable weight savings occur when Kapton is the conductor sheath. But as noted, Kapton has poor mechanical performance. Hence we often use a sheath called TKT, meaning a bulk of Kapton with an outer and inner layer of Teflon. The Teflon provides superior abrasion resistance and protects the Kapton underneath, which provides the electrical resistance. The inner layer of Teflon prevents chafing between the conductor and the sheath as the cable harness flexes.
One of the problems with Apollo 1 was the use of PVC insulation. Ordinary flexible PVC has a flammability rating in the mid-20s. The flammability rating is the percentage of oxygen needed to sustain combustion. Under normal room conditions, PVC is self-extinguishing. In a pure oxygen environment it is not, and further releases gaseous chlorine as it burns. Kapton replaced PVC as the Apollo electrical insulator.
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Re-read Lost Moon recently. In many ways, the particular parts dealing with Apollo 1 was more horrific than watching the opening section of Ron Howard's Apollo 13. :'(
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Just some idle thoughts on the issue at hand.
Eletrically, conductors will still conduct. 40 years of exposure, well, who can be sure.
Mechanically, connections would likely be loosened with the temperature extremes. That being said, These things are deliberately designed to survive. Look at voyager 1 and 2, or Pioneer, or Surveyer.
Environmentally, unknown. The expectation was that the cheapy flags would have long since disintegrated, but they are still there as their shadows attest.
Finally, when the LM took off from the lunar surface, explosive bolts were used. Anything explosive will be causing collateral damage.
If you wish to consider whether one could simply go and turn on the remaining descent stage, well, no, not a chance. It is not even that it cannot. It's that it was designed to be abandoned on the Lunar surface.
ETA: I have no issue speculating about the current condition of the various Descent modules, But I can guarantee you none are flight ready.
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Following experience with the results of fires caused by hits in action off the Falklands the RN changed the wiring spec on it's ships in the 80s. They removed miles of cables from ships already in service and changed the spec of cables for new ships. As well as giving off toxic fumes when burnig or heated conducted heat through bulkheads and decks damaged existing cables in adjacent compartments.
But, as above, this isn't something that was too much of a worry on Apollo, I don't think anyone was firing missiles at them.
Did the Type 22's and 42's have Kapton in them? I thought (I am sure I read somewhere!) that a big problem was extensive use of lightweight Magnesium Alloys in the ship construction. Lets face it the Exocet that hit Sheffield didn't explode it was just the Missile fuel that caused the massive fire...magnesium would have gone a long way to help that!.. that and the Polyester works dress trousers didn't bode well for the Matlows on board! (When I got posted to Northern Ireland in 86 we were issued with 1960's 'denims', cotton instead of Polyester, in case we got hit by a firebomb!)
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It was the Type 21 that was the problem and to some extent the 42. They didn't use Kapton but they did have a lot of PVC in the wiring. Type 21 Amazon Class were built by Vospers who were touting for exports and lobbied to be allowed to design ships free from the apparently 'conservative' restrictions of the RN design board. They were liked by the Treasury because they were considerably cheaper than the Leanders that the RN wanted more of (Best AS and General purpose escort ever built imho). and were also seen as export winners. In the end the RN ordered 8 and they looked good and that's about it. Wikipedia has a good summery of their failings.
They shouldn't have been sent to the South Atlantic, they were just overgrown 'Gun Boats' designed to appeal to South American and Asian governments.
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I learned from experience (by guessing the wrong answer to "what's that smell?") that burning Kapton stinks somewhat like decomposing flesh, and nothing at all like an electrical fire.
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Burning Kapton is . . . better? In most circumstances?
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Burning Kapton is . . . better? In most circumstances?
About as healthy as any good kitchen fire. It's better than PVC, which produces large quantities of hydrochloric acid when burned, but Kapton is also more likely to cause a fire due to poor abrasion resistance. Teflon is nearly as heat resistant as Kapton and handles abrasion much better. Its decomposition products will kill birds and make people sick, but if substantial amounts of Teflon insulation are being thermally decomposed, it's probably unhealthy to stick around anyway. (Note: don't leave Teflon-coated cookware empty on a hot stove.)
Silicone is probably the best thing to have in a fire, just don't breathe the silica dust that results.