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Post by the light works on Aug 10, 2014 4:20:42 GMT
Is The Last Ship’s USS Nathan James Based on a Real Ship?"Are parachute style kite sails really used to pull ships? Yes. On The Last Ship TV show, crew members of the USS Nathan James fire three parachutes into the air, which deploy and begin to pull the ship. The concept is based on a real technology that debuted in 2008 as a way for modern steel ships to harness wind power and in turn cut down on fuel consumption. The episode simplifies the launching process of the kite sails (they’re not fired into the air out of handheld guns) and exaggerates the number of sails (normally just one). The sky sail is also controlled and monitored by a complicated computer system and is designed to assist a working engine, rather than make up for a non-functioning one." It includes a video of the SkySails system being used. These end of the world virus series/movies are just stupid. Ebola has a fatality rate of 90%. If the entire planet became infected with ebola, the survivors are the ones with the immunity system to kill it. Those are the ones are the ones you want to survive. They haven't even eradicated the common cold. But Hollywood, and sadly the American public, always get it wrong when it comes to viral diseases. On the power generating side: The Arleigh Burke class destroyer is equipped with 3 Allison AG9140 Generators for electricity and 4 General Electric LM2500-30 gas turbines for propulsion, so losing the propulsion system would have no impact on power generation and moving the propeller wouldn't generate electricity. Most US Navy ships have generators in addition to a propulsion system. The planned Zumwalt class destroyer will have 2 Rolls Royce engines for propulsion and 2 for power generation. Kidd class (predecessor of Arleigh Burke class) had 3 engines for propulsion and 2 for electricity. The nuclear ships have steam turbines for propulsion and other steam turbines for electricity. The Nimitz class carrier has 4 turbines for propulsion and 8 for electricity. the skysail company debuted in 2008. the ides of kites for sails has been around at least since 87, when I first heard of it.
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Post by silverdragon on Aug 10, 2014 8:41:12 GMT
As per Toms post, getting the prop shaft connected to the generators would then require some hefty re- engineering of the engine room.... If thats even where they keep the generators.
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Post by silverdragon on Aug 10, 2014 8:43:43 GMT
They have been around longer than that...? "Spinnaker", its a triangular sail at the front of a ship that is no more than a Kite on a very short leash?....
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Post by the light works on Aug 10, 2014 13:38:43 GMT
They have been around longer than that...? "Spinnaker", its a triangular sail at the front of a ship that is no more than a Kite on a very short leash?.... too short to count as a kite.
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Post by silverdragon on Aug 11, 2014 7:18:09 GMT
So when is a sail a kite then?.... Or when is a kite just a sail?... What defines a kite....
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Post by the light works on Aug 11, 2014 14:16:58 GMT
So when is a sail a kite then?.... Or when is a kite just a sail?... What defines a kite.... my definition of a kite would be that the kite supports its shape independently of the anchor points of the main flying lines. - which is to say, all of the connecting lines between the kite and an anchor point could come through a single point (or as close to a single point as the diameter allows) and be of any length without affecting the shape of the kite (again, within reason - if the lines are so short they collapse the kite, that doesn't count) or for the short answer: a kite doesn't require a mast.
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Post by silverdragon on Aug 12, 2014 7:35:38 GMT
Define "mast". If that is a "Stick" that controls the shape of the "sail" then the kites that have long control bars to "Fly" them, as in stunt kites, are therefore not a kite?....
You can see where I am going here. Its all down to pedantic's of definition.... As Spinnakers can be controlled and "Flown" in certain circumstances to change their shape and amount of force, I suspect that there has been crossing technology between them and Kites.
Kite boards both Water and Land based are using a Kite as a sail..... The idea of using Kites to move a ship, well, thats just backwards, they are re-inventing the sail, are they not?... The term Sky-sail actually refers to the top most sail on a sailing ship .. which is the origin of the term Sky-Scraper.....very high, very tall, again a naval term is used by land-lubbers.
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Post by the light works on Aug 12, 2014 14:06:57 GMT
Define "mast". If that is a "Stick" that controls the shape of the "sail" then the kites that have long control bars to "Fly" them, as in stunt kites, are therefore not a kite?.... You can see where I am going here. Its all down to pedantic's of definition.... As Spinnakers can be controlled and "Flown" in certain circumstances to change their shape and amount of force, I suspect that there has been crossing technology between them and Kites. Kite boards both Water and Land based are using a Kite as a sail..... The idea of using Kites to move a ship, well, thats just backwards, they are re-inventing the sail, are they not?... The term Sky-sail actually refers to the top most sail on a sailing ship .. which is the origin of the term Sky-Scraper.....very high, very tall, again a naval term is used by land-lubbers. it is a stick attached to a secure basis, which directly controls the shape of the cloth, and has at least one point of the cloth attached on a short lead. the control bar on a stunt kite is not attached by a short lead, and does not directly control the shape of the kite - as the kite may do a complete 360 degree rotation in relation to the stick (twisting the control lines around themselves) without losing its shape. a spinnaker is not a kite. if you tie the lines of a spinnaker to the end of a 100' rope and attempt to fly it, it will collapse. no, Sky sail refers to a registered international company that produces a giant version of a kiteboarding kite, for use by ships. the uppermost sails on a square rigged ship were referred to as topsails.
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Post by the light works on Aug 12, 2014 14:20:13 GMT
Kite. __________________________________________________________________________ sail. any questions?
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Post by rick4070 on Aug 12, 2014 16:43:16 GMT
I hope I'm not hijacking the thread, I've been watching the show too, and the part about the solar stills to purify water might have a "myth" in it too. I saw that they were using beer, (Coors, I'm pretty sure, which is almost all water anyways..) and they also opened up what looked like large cans of fruit, and poured all the fluids into their stills. Why not just use sea water, would it not work as well or better? Ideas could be: could you make a working solar still from things found on the ship? Would fruit juice and beer work better than sea water in a solar still?
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Post by Lokifan on Aug 12, 2014 18:58:57 GMT
I hope I'm not hijacking the thread, I've been watching the show too, and the part about the solar stills to purify water might have a "myth" in it too. I saw that they were using beer, (Coors, I'm pretty sure, which is almost all water anyways..) and they also opened up what looked like large cans of fruit, and poured all the fluids into their stills. Why not just use sea water, would it not work as well or better? Ideas could be: could you make a working solar still from things found on the ship? Would fruit juice and beer work better than sea water in a solar still? Very good point. Since alcohol has a lower boiling point then water, would it be a waste of time to try to distill it? Or are they distilling the alcohol first, then, once it's the distillate, drinking the now-alcohol free beer?
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Post by rick4070 on Aug 12, 2014 20:57:46 GMT
I hope I'm not hijacking the thread, I've been watching the show too, and the part about the solar stills to purify water might have a "myth" in it too. I saw that they were using beer, (Coors, I'm pretty sure, which is almost all water anyways..) and they also opened up what looked like large cans of fruit, and poured all the fluids into their stills. Why not just use sea water, would it not work as well or better? Ideas could be: could you make a working solar still from things found on the ship? Would fruit juice and beer work better than sea water in a solar still? Very good point. Since alcohol has a lower boiling point then water, would it be a waste of time to try to distill it? Or are they distilling the alcohol first, then, once it's the distillate, drinking the now-alcohol free beer? I guess that they could use the alcohol for something else. And, I would guess that the left over "beer" would be pretty nasty tasting. I think I would just leave the beer out, even if alcohol is a diuretic, beer is still mostly water, (Coors is what, around 4% ABV?) and could be used sparingly.
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Post by silverdragon on Aug 13, 2014 12:36:05 GMT
I call on Cybermortis here to verify that Sky-sail was the name of the top most sail on a square rigger. It also appears as a term in my Spellchuckler... so not a registered trade mark, which would require me to "OK" it as acceptable.
I also cite my family member who reckons if you tie it right, a Spinnaker would act as a parachute... not a very good one, but it would slow you down if you tried to tow it. Therefore, dont try to tow a sailing ship backwards.....
I know we are arguing pedantic, "Just for fun", but sometimes that gets results. I have asked that family member about use of parachute as a sky-sail.... He says why didnt they just rig up the cute from a mast on the ship, the winds down at ship level are more reliable than high level winds, and as you can see them, you can change direction of the "Sail" quicker.... He got a point there I think?.... If the wind shifts at high altitude, the chute may just drop, hit the water, and become an anchor. You would have to reel it in and start again... If the chute was a sail on a mast, you just change trim to suit the change in wind?....
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Post by the light works on Aug 13, 2014 14:05:14 GMT
I call on Cybermortis here to verify that Sky-sail was the name of the top most sail on a square rigger. It also appears as a term in my Spellchuckler... so not a registered trade mark, which would require me to "OK" it as acceptable. I also cite my family member who reckons if you tie it right, a Spinnaker would act as a parachute... not a very good one, but it would slow you down if you tried to tow it. Therefore, dont try to tow a sailing ship backwards..... I know we are arguing pedantic, "Just for fun", but sometimes that gets results. I have asked that family member about use of parachute as a sky-sail.... He says why didnt they just rig up the cute from a mast on the ship, the winds down at ship level are more reliable than high level winds, and as you can see them, you can change direction of the "Sail" quicker.... He got a point there I think?.... If the wind shifts at high altitude, the chute may just drop, hit the water, and become an anchor. You would have to reel it in and start again... If the chute was a sail on a mast, you just change trim to suit the change in wind?.... the winds must work different where you are... over here, the higher level winds - above tree level - will blow at essentially the same speed and direction all day and into the night. surface winds can fluctuate as much as 10 knots and 25 degrees at any given time; and are always at least a few knots slower than winds out of the surface effect. so, according to wikipedia, some square riggers did call their topsail a skysail - though sometimes topped by a moonsail or moonraker. en.wikipedia.org/wiki/Full-rigged_shiphowever, look at what comes up if you simply google skysail. www.google.com/search?q=wikipedia+parts+of+a+square+rigger&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&channel=fflb#channel=fflb&q=skysail&rls=org.mozilla:en-US:official
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Post by Cybermortis on Aug 13, 2014 15:38:31 GMT
The sails on a square rigged ship were, from bottom to top, Main or Course, top, top gallant and Royal. It does appear as if some ships had 'sails' of sorts located above the royals, which would probably have been a small sail attached to the rigging rather than the mast itself. (Certainly not on a yardarm).
It is possible that 'skysails' and 'skyscrapers' were from sailing ships in the mid to late 1800's, since I've seen a couple of paintings of ships that had at least five distinct sails rather than four. I'm not aware of ships in earlier periods having that many sails on any mast - or at least not yards.
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Post by Lokifan on Aug 13, 2014 15:48:33 GMT
According to Merriam-Webster, the definition of skysail is the sail above the royal.
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Post by silverdragon on Aug 14, 2014 7:19:35 GMT
From Wikapedia, .... first page of any search results of sky sail. I have also noted that Sky Scraper was original used as a description of the taller tall rigger ships that came into port. Before they built that high, some of the ships were taller than any building known to man... And we are talking of Man who hadn't discovered or known about Pyramids or ancient artefact buildings, just Man that worked lived and probably never went much further than 50 mile from his home port on land, or sailors that had never seen a buidling in port as high as the ships he sailed on. That reference to a Moon sail is a new one to me even?... The sky-scraper as a sail may be then a ba$tardization of the sky-sail, or maybe the flag that was above that, or may be the rigging that carried that sail. Its original meaning has bee bent over the centuries?.... However, Sky-Scraper has been used for anything tall, as much as Jumbo, which originally was the name of an elephant is used for anything BIG. All sources I can quote here are now only are Web based, and lots of knowledge existed before we invented the internets?... [Edit][Late addition... I just read that the Sky Sail its self was only loosely tied on to the mast... That it, the long pole that held it out, the rigging, was lashed on above the royal sail, it was to all extents removable. Does that count as a one piece "Kite"..... ]
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Post by Cybermortis on Aug 14, 2014 10:00:34 GMT
I've heard of 'skyscraper' in relation to a sail. I guess it is also possible that the term was an older one for what became known as a skysail, or a generic term for the highest sail a ship could carry. I've not seen skysails on any rigging plans, which implies that anything above the royals was probably not part of a ships 'official' sailing rig. Or at least not for the ships I'm familiar with - which had wooden masts.
From what I can tell skysails on earlier ships must have been attached to the flag pole that rose up above the Royal Mast. This was not a mast as such, rather a literal pole on which the ship carried flags, pendents etc (used for signaling). As such any sail attached to it would have to be small, and probably couldn't be used in strong wings lest the pole break.
I'm actually wondering if the original Skysails might not have been a yard and sail taken from a ships boats, rather than 'officially' issued.
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Post by the light works on Aug 14, 2014 13:51:16 GMT
From Wikapedia, .... first page of any search results of sky sail. I have also noted that Sky Scraper was original used as a description of the taller tall rigger ships that came into port. Before they built that high, some of the ships were taller than any building known to man... And we are talking of Man who hadn't discovered or known about Pyramids or ancient artefact buildings, just Man that worked lived and probably never went much further than 50 mile from his home port on land, or sailors that had never seen a buidling in port as high as the ships he sailed on. That reference to a Moon sail is a new one to me even?... The sky-scraper as a sail may be then a ba$tardization of the sky-sail, or maybe the flag that was above that, or may be the rigging that carried that sail. Its original meaning has bee bent over the centuries?.... However, Sky-Scraper has been used for anything tall, as much as Jumbo, which originally was the name of an elephant is used for anything BIG. All sources I can quote here are now only are Web based, and lots of knowledge existed before we invented the internets?... [Edit][Late addition... I just read that the Sky Sail its self was only loosely tied on to the mast... That it, the long pole that held it out, the rigging, was lashed on above the royal sail, it was to all extents removable. Does that count as a one piece "Kite"..... ]if you can tie it on a 100' line and fly it above the ship.
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Post by memeengine on Aug 14, 2014 16:43:13 GMT
From Wikapedia, .... first page of any search results of sky sail. [Edit][Late addition... I just read that the Sky Sail its self was only loosely tied on to the mast... That it, the long pole that held it out, the rigging, was lashed on above the royal sail, it was to all extents removable. Does that count as a one piece "Kite"..... ]Skysails, like most of the other sails in the sail plan, evolved over time. By the end of the clipper era, the skysail was a square sail on its own mast above the royal, with a small square moon sail above. Anyone really interested might want to look up a copy of "Fast Sailing Ships, 1775-1875" by David R. MacGregor (Nautical Publishing co, 1973), which includes many diagrams and photos of these vessels. Of passing relevance to this thread, that author refers on several occasions to a ship's "flying kites". A term which appears to apply collectively to the supplementary sails such as the studding sails, spritsails, watersails and skysails, used when a ship was carrying every bit of available canvas. The same term in the same context is mentioned in Captain Hall's "Sketches of sea life" (published in the Quarterly Review, Vol. 45, 1831) when he mentions "...fanning out the skysails and other flying kites, generally supposed to be superfluous, but which, on occasions as this, do good service by catching the first breath of air that always seems to float far above the water" which also gives an explanation of their purpose.
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