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#51
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The Melting Deck Plates Muddle - V-22 on LHD deck....
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#52
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The Melting Deck Plates Muddle - V-22 on LHD deck....
On Dec 11, 8:35 am, "Ken S. Tucker" wrote:
On Dec 10, 4:09 pm, frank wrote: On Dec 10, 1:00 pm, "Ken S. Tucker" wrote: On Dec 10, 7:24 am, Jack Linthicum wrote: On Dec 10, 8:53 am, "Roger Conroy" wrote: "Bill Kambic" wrote in message .. . On Thu, 10 Dec 2009 02:57:36 -0800 (PST), Jack Linthicum wrote: snipped for brevity Or use the rocket launch technique and spray water across the take-off area. Probably less than optimal. Large clouds of hot, salt water steam would be an annoyance (at a minimum) to the deck crew. It would also be a highly corrosive material that could serious complicate maintenance of both ship and aircraft. Use of fresh water would likely be an excessive demand on the evaporators. The piping of cooling water suggested earlier would be a better idea. It would likely be cheaper that major modifications such as a "ski jump" and permit the continued use of the vertical capability of the aircraft. A water cooled heatsink built into a part of the deck designated for "hot" aircraft makes a lot of sense. You could have a place underneath to stash beer, like the old sub- mariners did. In electronics, we have similiar problems, we usually solve using Al heat sinks, fan air cooled, as the cheapest. Screw a few Al heat sinks to the bottom of the locations of the deck permited to take the heat and engage any fluid to cool it, even water if space is tight, yawn. Ken Pray tell, young Skywalker, what type of electronics have you designed that has a few thousands pounds of metal land on it, controlled by a navel aviatrix, blasting used JP4 and other noxious and profane gasses as high speeds and easily a thousand degrees of the Farenheits? I'm getting a case of beer and a lot of popcorn, this is going to be a good one. Note to Wiki: another cite for the 'Why do EE degrees have a BS in front of them....' Frank, note you've replied to me 3 times, somewhat sarcastically on a topic that is borderline boring for most, but I own a patent on a 'new and improved' woodstove, so I have an extra interest and specialized knowledge on the subject, so I find the problem intriguing, About "degrees", and "diploma's" mine are buried somewhere in archives, rusting away. Ken Too add, 'refractory concrete' is a material we've considered to form super high quality woodstoves, I suppose I could sell the USN some to drowel over their selected deck portions. Ken |
#53
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The Melting Deck Plates Muddle - V-22 on LHD deck....
In article
318346c5-4734-47d5-9883-9ee8872cc6a7@c3 g2000yqd.googlegroups.com, frank wrote: On Dec 10, 11:58*pm, "Malcom \"Mal\" Reynolds" atlas- wrote: In article 93ee764a-0400-499b-b519-37e47ef04416@v2 5g2000yqk.googlegroups.com, *Richard wrote: On Dec 9, 11:23*pm, "Malcom \"Mal\" Reynolds" atlas- wrote: In article 3f72b032-2be2-4377-a180-01d7a81404fe@d2 1g2000yqn.googlegroups.com, *Mike wrote: StrategyPage.com December 2, 2009 The Melting Deck Plates Muddle by James Dunnigan Earlier this year, the U.S. Navy discovered that the heat from the MV-22's gas turbine engines, which blow their exhaust right on to the deck of the LHD while waiting to take off, caused high enough temperatures to the steel under the deck plates, to possibly warp the understructure. This was already a known potential problem with the new F-35B vertical takeoff jet fighter. So now the Navy has two hot new aircraft that require an innovative solution to the melting deck problem. The Navy also discovered that the exhaust heat problem varied in intensity between different classes of helicopter carriers (each with a different deck design.) The Navy is looking for a solution that will not require extensive modification of current carrier decks. This includes a lot of decks, both the eleven large carriers, and the ten smaller LHAs and LHDs. This is shaping up as another multi-billion dollar "oops" moment, as the melting deck problem was never brought up during the long development of either aircraft. Previously, the Harrier was the only aircraft to put serious amounts of heat on the carrier deck, but not enough to do damage. But when you compare the Harrier engine with those on the V-22 and F-35B, you can easily see that there is a lot more heat coming out of the two more recent aircraft. Someone should have done the math before it became a real problem. Use what NASA uses for the shuttle? Wouldn't cost that much at all Yeah except for not walking, parking, raining, hailing or dropping a wrench on the coating it would be great. Actually I was thinking of what they do at the launch pad during launch, not the tiles on the shuttle Ever see photos of the pad, there is a large water tower near it. I think 3 seconds before launch, when engines start up, there is a water infusion into the bucket that thrust goes into. Think multiple streams of water. Sucker lights up, hits the water, massive steam and thrust go out the channels away from the launch pad. That's the big clouds that occur. Makes pad much more reusable. I think Shuttle was first system to use that, could be wrong. Makes entire complex much more reusable. If you can get some old Shuttle launch footage, that's one of the standard shots from NASA and main engine start. Awesome. Lots of plumbing though. That's why I suggested it. Of course the massive steam wasn't in my thinking when I did. I suppose the idea of running cold water under the deck to absorb the heat would be best, might even be able to use the heat for something (pre-heating the water to be desalinated?) |
#54
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The Melting Deck Plates Muddle - V-22 on LHD deck....
On Dec 10, 2:21*pm, Jack Linthicum
wrote: On Dec 10, 3:44*pm, "Mr.Smartypants" wrote: On Dec 9, 9:22*pm, Mike wrote: StrategyPage.com December 2, 2009 The Melting Deck Plates Muddle by James Dunnigan Earlier this year, the U.S. Navy discovered that the heat from the MV-22's gas turbine engines, which blow their exhaust right on to the deck of the LHD while waiting to take off, caused high enough temperatures to the steel under the deck plates, to possibly warp the understructure. This was already a known potential problem with the new F-35B vertical takeoff jet fighter. So now the Navy has two hot new aircraft that require an innovative solution to the melting deck problem. The Navy also discovered that the exhaust heat problem varied in intensity between different classes of helicopter carriers (each with a different deck design.) The Navy is looking for a solution that will not require extensive modification of current carrier decks. This includes a lot of decks, both the eleven large carriers, and the ten smaller LHAs and LHDs. This is shaping up as another multi-billion dollar "oops" moment, as the melting deck problem was never brought up during the long development of either aircraft. Previously, the Harrier was the only aircraft to put serious amounts of heat on the carrier deck, but not enough to do damage. But when you compare the Harrier engine with those on the V-22 and F-35B, you can easily see that there is a lot more heat coming out of the two more recent aircraft. Someone should have done the math before it became a real problem. Distortion or warping of steel plating due to expansion from high temperatures is a far cry from "melting". 1700 degrees was mentioned in one article.- That would still be "distortion" not "melting". |
#55
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The Melting Deck Plates Muddle - V-22 on LHD deck....
On Dec 11, 4:45*pm, "Mr.Smartypants"
wrote: On Dec 10, 2:21*pm, Jack Linthicum wrote: On Dec 10, 3:44*pm, "Mr.Smartypants" wrote: On Dec 9, 9:22*pm, Mike wrote: StrategyPage.com December 2, 2009 The Melting Deck Plates Muddle by James Dunnigan Earlier this year, the U.S. Navy discovered that the heat from the MV-22's gas turbine engines, which blow their exhaust right on to the deck of the LHD while waiting to take off, caused high enough temperatures to the steel under the deck plates, to possibly warp the understructure. This was already a known potential problem with the new F-35B vertical takeoff jet fighter. So now the Navy has two hot new aircraft that require an innovative solution to the melting deck problem. The Navy also discovered that the exhaust heat problem varied in intensity between different classes of helicopter carriers (each with a different deck design.) The Navy is looking for a solution that will not require extensive modification of current carrier decks. This includes a lot of decks, both the eleven large carriers, and the ten smaller LHAs and LHDs. This is shaping up as another multi-billion dollar "oops" moment, as the melting deck problem was never brought up during the long development of either aircraft. Previously, the Harrier was the only aircraft to put serious amounts of heat on the carrier deck, but not enough to do damage. But when you compare the Harrier engine with those on the V-22 and F-35B, you can easily see that there is a lot more heat coming out of the two more recent aircraft. Someone should have done the math before it became a real problem. Distortion or warping of steel plating due to expansion from high temperatures is a far cry from "melting". 1700 degrees was mentioned in one article.- That would still be "distortion" not "melting". Here are some numbers some from an amendment BAA 09-031 Amendment 0001 Side note: [Iron, out of the ground, melts at around 1510 degrees C (2750°F). Steel often melts at around 1370 degrees C (2500°F).] ONR is looking for thermal management technologies that can keep the deck surface temperature below 300ºF when exposed to MV-22 exhaust plumes for 90 minutes before takeoff, and F-35B exhaust plumes for 2 minutes when landing. And cooling the deck is not enough - any solution has to be compatible with the deck's non-skid coating. It also has to be affordable and capable of being installed below deck or retrofitted above deck. Tall order. “Structural Evaluation of an LHD-Class Amphibious Ship Flight Deck Subjected to Exhaust Gas Heat from a MV-22 Osprey Aircraft,” they note that deck buckling occurs at a temperature of 160oF to 170oF. Where does the 300oF limit originate? Response: The 300 degree F is derived from the temperature limit of the tires on aircraft. How concentrated is the heat flux, how large an area is involved in the 24,000BTU/min heating? I have had difficulty getting any numbers and the information heat flux given in the BAA did not include an area component. Response: A range of 3-foot to 10-foot diameter is suggested. Max exhaust temperature anticipated? Response: This is tightly controlled. A range of max temperatures could be 1000– 1700 deg. F. http://www.onr.navy.mil/~/media/File...amend0001.ashx |
#56
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The Melting Deck Plates Muddle - V-22 on LHD deck....
On Fri, 11 Dec 2009 04:30:02 -0800 (PST), Jack Linthicum
wrote: On Dec 11, 2:42*am, frank wrote: On Dec 10, 11:58*pm, "Malcom \"Mal\" Reynolds" wrote: *Richard wrote: On Dec 9, 11:23*pm, "Malcom \"Mal\" Reynolds" wrote: *Mike wrote: StrategyPage.com December 2, 2009 The Melting Deck Plates Muddle by James Dunnigan Earlier this year, the U.S. Navy discovered that the heat from the MV-22's gas turbine engines, which blow their exhaust right on to the deck of the LHD while waiting to take off, caused high enough temperatures to the steel under the deck plates, to possibly warp the understructure. This was already a known potential problem with the new F-35B vertical takeoff jet fighter. So now the Navy has two hot new aircraft that require an innovative solution to the melting deck problem. The Navy also discovered that the exhaust heat problem varied in intensity between different classes of helicopter carriers (each with a different deck design.) The Navy is looking for a solution that will not require extensive modification of current carrier decks. This includes a lot of decks, both the eleven large carriers, and the ten smaller LHAs and LHDs. This is shaping up as another multi-billion dollar "oops" moment, as the melting deck problem was never brought up during the long development of either aircraft. Previously, the Harrier was the only aircraft to put serious amounts of heat on the carrier deck, but not enough to do damage. But when you compare the Harrier engine with those on the V-22 and F-35B, you can easily see that there is a lot more heat coming out of the two more recent aircraft. Someone should have done the math before it became a real problem. Use what NASA uses for the shuttle? Wouldn't cost that much at all Yeah except for not walking, parking, raining, hailing or dropping a wrench on the coating it would be great. Actually I was thinking of what they do at the launch pad during launch, not the tiles on the shuttle Ever see photos of the pad, there is a large water tower near it. I think 3 seconds before launch, when engines start up, there is a water infusion into the bucket that thrust goes into. Think multiple streams of water. Sucker lights up, hits the water, massive steam and thrust go out the channels away from the launch pad. That's the big clouds that occur. Makes pad much more reusable. I think Shuttle was first system to use that, could be wrong. Makes entire complex much more reusable. If you can get some old Shuttle launch footage, that's one of the standard shots from NASA and main engine start. Awesome. Lots of plumbing though. One of the professed goals of the system is sound suppression. That's one of the events the crowds come to the launches for---that magnificent roar like the end of the world. Well you could hear the damned things 60 miles away at the site of the old NNPS. Dave --- who watched STS-2 take off while on "cigarette break" during Pre NPS. Everyone was out there. The break was supposed to end about a minute or two before launch. The instructors actually tried to get us to go inside. It didn't work. -- "...you know, it seems to me you suffer from the problem of wanting a tailored fit in an off the rack world." Dennis Juds |
#57
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The Melting Deck Plates Muddle - V-22 on LHD deck....
Ken S. Tucker wrote:
On Dec 10, 4:09 pm, frank wrote: On Dec 10, 1:00 pm, "Ken S. Tucker" wrote: On Dec 10, 7:24 am, Jack Linthicum wrote: On Dec 10, 8:53 am, "Roger Conroy" wrote: "Bill Kambic" wrote in message ... On Thu, 10 Dec 2009 02:57:36 -0800 (PST), Jack Linthicum wrote: snipped for brevity Or use the rocket launch technique and spray water across the take-off area. Probably less than optimal. Large clouds of hot, salt water steam would be an annoyance (at a minimum) to the deck crew. It would also be a highly corrosive material that could serious complicate maintenance of both ship and aircraft. Use of fresh water would likely be an excessive demand on the evaporators. The piping of cooling water suggested earlier would be a better idea. It would likely be cheaper that major modifications such as a "ski jump" and permit the continued use of the vertical capability of the aircraft. A water cooled heatsink built into a part of the deck designated for "hot" aircraft makes a lot of sense. You could have a place underneath to stash beer, like the old sub- mariners did. In electronics, we have similiar problems, we usually solve using Al heat sinks, fan air cooled, as the cheapest. Screw a few Al heat sinks to the bottom of the locations of the deck permited to take the heat and engage any fluid to cool it, even water if space is tight, yawn. Ken Pray tell, young Skywalker, what type of electronics have you designed that has a few thousands pounds of metal land on it, controlled by a navel aviatrix, blasting used JP4 and other noxious and profane gasses as high speeds and easily a thousand degrees of the Farenheits? I'm getting a case of beer and a lot of popcorn, this is going to be a good one. Note to Wiki: another cite for the 'Why do EE degrees have a BS in front of them....' Frank, note you've replied to me 3 times, somewhat sarcastically on a topic that is borderline boring for most, but I own a patent on a 'new and improved' woodstove, so I have an extra interest and specialized knowledge on the subject, so I find the problem intriguing, About "degrees", and "diploma's" mine are buried somewhere in archives, rusting away. Ken Great, now post a link to that patent. Dan, U.S. Air Force, retired |
#58
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The Melting Deck Plates Muddle - V-22 on LHD deck....
On Thu, 10 Dec 2009 15:59:24 -0800 (PST), frank
wrote: On Dec 10, 2:41Â*pm, "Ken S. Tucker" wrote: On Dec 10, 11:04 am, Jack Linthicum wrote: On Dec 10, 2:00 pm, "Ken S. Tucker" wrote: On Dec 10, 7:24 am, Jack Linthicum wrote: On Dec 10, 8:53 am, "Roger Conroy" wrote: "Bill Kambic" wrote in message .. . On Thu, 10 Dec 2009 02:57:36 -0800 (PST), Jack Linthicum wrote: snipped for brevity Or use the rocket launch technique and spray water across the take-off area. Probably less than optimal. Â*Large clouds of hot, salt water steam would be an annoyance (at a minimum) to the deck crew. Â*It would also be a highly corrosive material that could serious complicate maintenance of both ship and aircraft. Use of fresh water would likely be an excessive demand on the evaporators. The piping of cooling water suggested earlier would be a better idea. It would likely be cheaper that major modifications such as a "ski jump" and permit the continued use of the vertical capability of the aircraft. A water cooled heatsink built into a part of the deck designated for "hot" aircraft makes a lot of sense. You could have a place underneath to stash beer, like the old sub- mariners did. In electronics, we have similiar problems, we usually solve using Al heat sinks, fan air cooled, as the cheapest. Screw a few Al heat sinks to the bottom of the locations of the deck permited to take the heat and engage any fluid to cool it, even water if space is tight, yawn. Ken Troll them in the water, saves having all those pipes. In conventional PC's like you prolly have, is a small fan sitting on the CPU Al heat sink. In the high watt stuff, oil circulation is used to cool the active components I've used. I'm not keen on oil, a friend of mine had a damn transformer explode on him and was showered with burning oil, it was not pretty, and is very painful. Also in my experience, I had a wood stove that started glowing low red (over heated, but it was cast iron) so I sprayed it with water to cool it, and that worked good. A good cast iron is pretty tough stuff, better than malleable at high temps I'm told. Learn that steam burns, did you? Let me guess, you're an engineer. Reminds me of our last night in boot camp. We had our coke stove glowing a nice comfortable red as we packed to ship out, when our friends from the next hut poured a bucket of water down the chimney. The cast iron lid went airborne and dense clouds of steam and cinders shot out, obscuring the electric lights. A mini Krakatoa. Well, I guess it's tradition that you never leave a perfectly shined floor for the next intake. . . |
#59
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The Melting Deck Plates Muddle - V-22 on LHD deck....
Ken S. Tucker wrote:
On Dec 11, 8:35 am, "Ken S. Tucker" wrote: On Dec 10, 4:09 pm, frank wrote: On Dec 10, 1:00 pm, "Ken S. Tucker" wrote: On Dec 10, 7:24 am, Jack Linthicum wrote: On Dec 10, 8:53 am, "Roger Conroy" wrote: "Bill Kambic" wrote in message ... On Thu, 10 Dec 2009 02:57:36 -0800 (PST), Jack Linthicum wrote: snipped for brevity Or use the rocket launch technique and spray water across the take-off area. Probably less than optimal. Large clouds of hot, salt water steam would be an annoyance (at a minimum) to the deck crew. It would also be a highly corrosive material that could serious complicate maintenance of both ship and aircraft. Use of fresh water would likely be an excessive demand on the evaporators. The piping of cooling water suggested earlier would be a better idea. It would likely be cheaper that major modifications such as a "ski jump" and permit the continued use of the vertical capability of the aircraft. A water cooled heatsink built into a part of the deck designated for "hot" aircraft makes a lot of sense. You could have a place underneath to stash beer, like the old sub- mariners did. In electronics, we have similiar problems, we usually solve using Al heat sinks, fan air cooled, as the cheapest. Screw a few Al heat sinks to the bottom of the locations of the deck permited to take the heat and engage any fluid to cool it, even water if space is tight, yawn. Ken Pray tell, young Skywalker, what type of electronics have you designed that has a few thousands pounds of metal land on it, controlled by a navel aviatrix, blasting used JP4 and other noxious and profane gasses as high speeds and easily a thousand degrees of the Farenheits? I'm getting a case of beer and a lot of popcorn, this is going to be a good one. Note to Wiki: another cite for the 'Why do EE degrees have a BS in front of them....' Frank, note you've replied to me 3 times, somewhat sarcastically on a topic that is borderline boring for most, but I own a patent on a 'new and improved' woodstove, so I have an extra interest and specialized knowledge on the subject, so I find the problem intriguing, About "degrees", and "diploma's" mine are buried somewhere in archives, rusting away. Ken Too add, 'refractory concrete' is a material we've considered to form super high quality woodstoves, I suppose I could sell the USN some to drowel over their selected deck portions. Ken Tucker, have you considered the differences in application? I didn't think so. Let me help. A wood stove is hot, yes, but there's no high velocity jet of extremely hot gases, is there? You would have to "drowel" more on after almost every mission. Dan, U.S. Air Force, retired |
#60
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The Melting Deck Plates Muddle - V-22 on LHD deck....
On Thu, 10 Dec 2009 23:42:41 -0800 (PST), frank
wrote: On Dec 10, 11:58Â*pm, "Malcom \"Mal\" Reynolds" atlas- wrote: In article 93ee764a-0400-499b-b519-37e47ef04416@v2 5g2000yqk.googlegroups.com, Â*Richard wrote: On Dec 9, 11:23Â*pm, "Malcom \"Mal\" Reynolds" atlas- wrote: In article 3f72b032-2be2-4377-a180-01d7a81404fe@d2 1g2000yqn.googlegroups.com, Â*Mike wrote: StrategyPage.com December 2, 2009 The Melting Deck Plates Muddle by James Dunnigan Earlier this year, the U.S. Navy discovered that the heat from the MV-22's gas turbine engines, which blow their exhaust right on to the deck of the LHD while waiting to take off, caused high enough temperatures to the steel under the deck plates, to possibly warp the understructure. This was already a known potential problem with the new F-35B vertical takeoff jet fighter. So now the Navy has two hot new aircraft that require an innovative solution to the melting deck problem. The Navy also discovered that the exhaust heat problem varied in intensity between different classes of helicopter carriers (each with a different deck design.) The Navy is looking for a solution that will not require extensive modification of current carrier decks. This includes a lot of decks, both the eleven large carriers, and the ten smaller LHAs and LHDs. This is shaping up as another multi-billion dollar "oops" moment, as the melting deck problem was never brought up during the long development of either aircraft. Previously, the Harrier was the only aircraft to put serious amounts of heat on the carrier deck, but not enough to do damage. But when you compare the Harrier engine with those on the V-22 and F-35B, you can easily see that there is a lot more heat coming out of the two more recent aircraft. Someone should have done the math before it became a real problem. Use what NASA uses for the shuttle? Wouldn't cost that much at all Yeah except for not walking, parking, raining, hailing or dropping a wrench on the coating it would be great. Actually I was thinking of what they do at the launch pad during launch, not the tiles on the shuttle Ever see photos of the pad, there is a large water tower near it. I think 3 seconds before launch, when engines start up, there is a water infusion into the bucket that thrust goes into. Think multiple streams of water. Sucker lights up, hits the water, massive steam and thrust go out the channels away from the launch pad. That's the big clouds that occur. Makes pad much more reusable. I think Shuttle was first system to use that, could be wrong. Makes entire complex much more reusable. If you can get some old Shuttle launch footage, that's one of the standard shots from NASA and main engine start. Awesome. Lots of plumbing though. Imagine being the pilot taking off through all that steam. Or landing, when visibility suddenly drops to zero as you come over the pad. Now imagine again, this time remembering that there's solid lumps of ship only a few yards from your rotors. . . A strong refractory coating seems much more attractive. |
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