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Post by the light works on Sept 10, 2014 14:12:30 GMT
for specifics, my boat has a 27 foot high aspect ratio sail. that means the mast is 27 feet tall, and the boom is about 7 feet long.
this is on a 17 foot boat that is about 300#.
now for a battleship, the best rig would probably be a catboat rig - this would allow you to step the mast in the forecastle a low aspect mast would be about the length of the vessel, and because of the superstructure, you would have to use a boomless design. but you're looking at a sail close to half the length of the vessel to get anything like an effective size to it. of course, standing rigging will be problematic - because a battleship is not designed to be lifted - so the mooring bollards, while fine for keeping it from going sideways, will not work well for tension going upwards. the next issue is that a battleship does not have a true keel, so your windward performance will be poor at best.
put in simple terms you can understand, putting a mast on a battleship to turn it into a sailboat is going to work almost as well as buying rope at a hardware store and tying down a piece of IDW load with it.
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Post by silverdragon on Sept 11, 2014 8:50:25 GMT
Question, in the trailer, and the last ship pictured by TLW, I know they are Radio masts. And..... Seriously, they look like the rigging used by sail ships...?... I have a plan. I am wondering. It perhaps not a good plan, but I have to ask anyway, just in case we are missing the Mammoth sitting in the corner with a pile of sticky buns?... I guess they are built "Sturdy"... how much extra rigging lines would you need to add to make sure they dont get bent, and how much square feet of Canvas can you hang out to dry from them?.... Can you do some simple strengthening as needed?... Again, you have a ship full of engineers doing not much, get them used for something useful?...
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Post by Cybermortis on Sept 11, 2014 9:48:17 GMT
You mean apart from trying to repair the engines and any additional damage taken when the engines went down?
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Post by the light works on Sept 11, 2014 14:32:37 GMT
Question, in the trailer, and the last ship pictured by TLW, I know they are Radio masts. And..... Seriously, they look like the rigging used by sail ships...?... I have a plan. I am wondering. It perhaps not a good plan, but I have to ask anyway, just in case we are missing the Mammoth sitting in the corner with a pile of sticky buns?... I guess they are built "Sturdy"... how much extra rigging lines would you need to add to make sure they dont get bent, and how much square feet of Canvas can you hang out to dry from them?.... Can you do some simple strengthening as needed?... Again, you have a ship full of engineers doing not much, get them used for something useful?... as one of us already said, no, it is not a good plan. the radio masts are designed to keep the antennae from coming crashing down onto the deck. they are not designed to be a point to anchor a towline onto . what you are suggesting is the equivalent of saying, "hey, this flagpole is hollow, that means it will be good for a cannon."
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Post by silverdragon on Sept 12, 2014 6:17:24 GMT
Designed for and put to use are the difference in human creativity. I doubt the sections of the Chicken Cannon were originally designed to punt Thawed birds into a windscreen.....
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Post by the light works on Sept 12, 2014 14:21:13 GMT
Designed for and put to use are the difference in human creativity. I doubt the sections of the Chicken Cannon were originally designed to punt Thawed birds into a windscreen..... let me explain to you what would have to be replaced to turn a destroyer into a sailing ship: the keel the hull the ballast the rudder system the deck everything constructed above the deck the hardpoints the masts the control system. in short, the easiest way to convert a destroyer to a sailboat would be to unbolt the figurehead and drive a sailboat under it.
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Post by silverdragon on Sept 13, 2014 8:55:26 GMT
You are not rebuilding the ship. You are just using what you have to create some kind of movement. You have got parachutes that you wish to "Tie off" somewhere?... Just where?.... They are providing thrust..... where are those forces attached to the ship?...
For all your rebuild needs to tie down sheets, I say that you are going to need exactly the same to use a Parachute as a sail?.... Its exactly the same forces being applied, instead of pushing, you are now pulling.
Sail or Parachute per 10ft square you have exactly the same force along the tie down lines.
Unless you seriously think the rubber soles of the squaddie hanging on to the other end of the chute have some magic attachment to the deck of the ship?...
100lb of pull is 100lb of pull..... now where you want me to tie this to?.. that figurehead maybe?...
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Post by Cybermortis on Sept 13, 2014 10:26:27 GMT
You are not rebuilding the ship. You are just using what you have to create some kind of movement. You have got parachutes that you wish to "Tie off" somewhere?... Just where?.... They are providing thrust..... where are those forces attached to the ship?... For all your rebuild needs to tie down sheets, I say that you are going to need exactly the same to use a Parachute as a sail?.... Its exactly the same forces being applied, instead of pushing, you are now pulling. Sail or Parachute per 10ft square you have exactly the same force along the tie down lines. Unless you seriously think the rubber soles of the squaddie hanging on to the other end of the chute have some magic attachment to the deck of the ship?... 100lb of pull is 100lb of pull..... now where you want me to tie this to?.. that figurehead maybe?... Try the bollards on the weather deck, you know those vertical structures ropes are tied to when a ship is being towed or moored. Or you could use the capstan, which even if it isn't powered is more than strong enough to handle the forces involved by design. The force you are taking about is the thrust coming off the sails/parachute. But with a sailing rig the force placed on the hull isn't just from the wind but also by the shifting mass of the mast itself. It is this shifting mass that is the real danger, and the reason that in windless conditions sailing ships could end up rolling their masts off the ship - the shifting mass of the masts was more than capable of snapping the stays or braces. Using what you have got to provide propulsion...No ship carries 400+ feet of steel tubing that could be made into a mast nor several miles of cable several inches thick. They simply don't have the space to carry such supplies, especially not for a system that is probably never going to be used on a ship outside training exercises.
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Post by the light works on Sept 13, 2014 13:02:57 GMT
You are not rebuilding the ship. You are just using what you have to create some kind of movement. You have got parachutes that you wish to "Tie off" somewhere?... Just where?.... They are providing thrust..... where are those forces attached to the ship?... For all your rebuild needs to tie down sheets, I say that you are going to need exactly the same to use a Parachute as a sail?.... Its exactly the same forces being applied, instead of pushing, you are now pulling. Sail or Parachute per 10ft square you have exactly the same force along the tie down lines. Unless you seriously think the rubber soles of the squaddie hanging on to the other end of the chute have some magic attachment to the deck of the ship?... 100lb of pull is 100lb of pull..... now where you want me to tie this to?.. that figurehead maybe?... Try the bollards on the weather deck, you know those vertical structures ropes are tied to when a ship is being towed or moored. Or you could use the capstan, which even if it isn't powered is more than strong enough to handle the forces involved by design. The force you are taking about is the thrust coming off the sails/parachute. But with a sailing rig the force placed on the hull isn't just from the wind but also by the shifting mass of the mast itself. It is this shifting mass that is the real danger, and the reason that in windless conditions sailing ships could end up rolling their masts off the ship - the shifting mass of the masts was more than capable of snapping the stays or braces. Using what you have got to provide propulsion...No ship carries 400+ feet of steel tubing that could be made into a mast nor several miles of cable several inches thick. They simply don't have the space to carry such supplies, especially not for a system that is probably never going to be used on a ship outside training exercises. put simply: the parachute rig is not putting its pull on the end of a lever. tying off to the bollards or the anchor chain will put the pull more or less forward - rather than trying to pull the bollards out of the deck like pulling nails with a crowbar.
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Post by silverdragon on Sept 14, 2014 9:12:59 GMT
Go back to what I pointed out about using Tie-downs to stabilise the "Mast".... The structure of the mast would be there to keep the ends of the sheet open, the pulling forces would pass down the tie downs to the tie down point. On the deck.
You mast then becomes no more than the spans in a Kite, just at lower level.
We are not trying here to recreate a full mast from a 17th century war ship, just enough mast to keep the ends of a parachute's worth of silk catching wind.
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Post by the light works on Sept 14, 2014 14:07:01 GMT
Go back to what I pointed out about using Tie-downs to stabilise the "Mast".... The structure of the mast would be there to keep the ends of the sheet open, the pulling forces would pass down the tie downs to the tie down point. On the deck. You mast then becomes no more than the spans in a Kite, just at lower level. We are not trying here to recreate a full mast from a 17th century war ship, just enough mast to keep the ends of a parachute's worth of silk catching wind. in that case, why not just tie the parachute off to the towline anchor at the bow and let the very efficient design of the parachute deal with both opening the parachute and keeping it open. (well, on the beach crew, we would hold the leading edge of the chute open to the wind, to help it inflate more reliably.) to elaborate: we would get to work at 8. drive the short bus down to our parking area, lay out our lines on the beach, tie on the line hangers, tie on the parachute, then open the parachute to the wind, and as soon as it was inflated we would let it go. at 6 or 7 or 8 at night, when the wind started slacking off, we would go hand over hand along the line, forcing the parachute back down to where we could reach the risers and "kill" the chute, so we could put everything away for the night.
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Post by silverdragon on Sept 15, 2014 8:17:01 GMT
Because I dont see why you need a cute open at 1,000 yards up where control is difficult, when you would get the same result on deck with instant control.....
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Post by the light works on Sept 15, 2014 13:55:29 GMT
Because I dont see why you need a cute open at 1,000 yards up where control is difficult, when you would get the same result on deck with instant control..... because 100 FEET up, it is clear of the surface fluctuations and doesn't NEED control. did you not see that we left the lines flying essentially unattended for 10-12 hours at a time? it is only if they are down in the surface winds that they need to be babysat.
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Post by silverdragon on Sept 16, 2014 7:58:15 GMT
But you can then only follow the wind. Down on deck, you can steer the sail and sail "upwind", if you have the skills.
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Post by Cybermortis on Sept 16, 2014 10:17:29 GMT
Except you are not 'down on the deck' but 150 feet or more above it. Sails on the deck have to be high enough to clear the superstructure and any eddies caused by it.
For both sail and chute the sail is NOT used to steer, for that you need a working rudder.
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Post by the light works on Sept 16, 2014 14:05:07 GMT
Except you are not 'down on the deck' but 150 feet or more above it. Sails on the deck have to be high enough to clear the superstructure and any eddies caused by it. For both sail and chute the sail is NOT used to steer, for that you need a working rudder. and a keel and a strong enough mast to withstand the side loading and strong enough standing rigging to withstand the tension, and enough ballast to keep the ship from simply flopping over. and a sail design that is capable of efficient sailing on the wind. - and that means a sail design that is not square rigged. no matter how you try to rephrase it, if you wanted to design a bot that was the opposite of a sailboat, a naval destroyer would come pretty close.
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Post by silverdragon on Sept 17, 2014 6:33:51 GMT
Eight sheets to the wind?... perhaps I need to explain better..... You steer the sails, to collect maximum wind. The rudder just controls the ships direction, if you have your sheets completely sideways to the wind, you aint going nowhere?...
The point I am trying to make is the Chute idea will only work in certain directions, as in you wont be able to steer the ship past 45degree to direction of wind, as past that the chute will just be dragging the ship sideways, with a sail, you can get 90degree to the wind with ease... and further...
The Chute will only be as useful as say a Spinnaker sail.
Again, we are not trying a full mast of six sails here, just one solitary sail, kept "Open" and in shape, by the mast, and all the pull being dispersed by a good bit of rope at four corners (Or more...) to the deck, and strong tie-down points. The mast will ONLY be used to give shape to the sail. The thrust will be collected by the rigging.
If you dont have strong enough tie down points for that, then I suggest you argument is self defeating, because where were you going to tie off your Chute anyway?....
Keel, yes, you may need one... but hang on, Destroyers have "Stabilisers" anyway dont they?... if this idea works and they are producing power, the stabilisers will be in use.
Plus again, we aint trying to get the ship over like a racing yacht here, just getting some momentum that is better than sitting still. 10 knots is a lot better than none at all.
Please note, I am not trying to be awkward or "Right" on this discussion, I am just arguing the other side of the discussion from what little I know about sailing....
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Post by Cybermortis on Sept 17, 2014 11:42:47 GMT
Didn't think you were.
In no particular order;
Trimming sails, to allow them to best catch the wind, requires that you physically move them from side to side. This requires that the yard to which the sail is attached be capable of being rotated around the mast. This requires a lot of men pulling on ropes and more men up in the rigging to further trim the sails while you are doing this. The masts on modern ships don't have movable yards, so you'd have to have one below them. Then you have the problem that the existing masts have cables supporting them (and I'd guess also acting as secondary power and communications lines to the equipment that is carried on the mast). These existing cables would prevent the yard from being moved more than a few degrees. The need to move the yards is another reason for not being able to put sails low down, there is equipment and structures that would get in the way, from the ships weaponry to the bridge. The only place you might be able to put a sail is at the stern, where the helicopter landing pad is located. That area would be clear enough to allow a spanker sail to rotate. But using a sail mounted at the stern makes steering difficult at best, since the stern is going to be pushed sideways with nothing to counter that from further ahead - ships sailing with a spanker sail usually also had a sail in place on the foremast to help with this. As I think I noted the skills needed to work even a basic sailing rig of this size are not something you are going to find on most modern ships, military or not. You *might* be lucky in having one or two men on board who (say) served on the USS Constitution. But even if you had four or five men that is simply not enough to work even a moderately sized sail - old merchant ships could get away with numbers like that because their sails were rather small and the crew experienced - FAR more experienced than anyone you are going to find on a modern ship. (The most inexperienced sailor on an old merchant ship would have been trimming sails and climbing rigging since the age of eight, if not even younger than that)
You are, again, missing that the tie-down points for a mast have to handle not just the force imparted by the wind, but ALSO the force imparted by the mass of the mast itself. With a parachute you have maybe sixty to a hundred pounds of weight to add to the thrust of the wind, which is nothing. Even a sudden burst of wind will not result in more force being passed onto the existing bollards than they can handle, its not going to come even close to doing so. With a mast however you have several tons of weight to add to the thrust, and this mass is not static but continually shifting in several directions at any given moment. This twisting turning force is something that the existing connection points on a modern ship were just not designed to handle. Even if the connections can handle the forces involved to start with, the continual motion is going to damage the ship if not rip those connections free (at which point the mast falls free and will rip the rest of the connections out and then either fall on the deck or possibly worse over the side where it risks tipping the ship). It is rather like having a nail hammered into a wall, you may not be able to putt it straight back out but if you pull on the nail in a circular motion sooner of later it will either pop back out or at least widen the top of the hole it was in - which in a ships context means doing serious damage to the decking.
You are also ignoring one other factor in why use parachutes rather than sails - the condition of the ship when you need to use an emergency propulsion system. Ships engines don't breakdown without reason, and on a modern warship the most likely reason for this is damage sustained from an hostile source or hitting an underwater obstruction. In both cases damage to the engines also means damage to the hull, which means that you are almost certainly taking on water and have flooded sections. This means that when you need your 'sail' chances are that the ship is already listing. Putting a mast up at this point is the last thing you want to do. You are trying to put a vertical structure up when the deck is not horizontal, you start with all of the weight of the mast having to be supported by the bollards on one side of the ship and last of all a tall heavy structure further decreases stability making it even more likely the ship will tip. In fact the additional weight high up is likely to increase the list and at best make repairing the hull even more difficult (not that you CAN think about repairing the hull when most of your crew is up on deck putting the mast up) and at worst is going to push that side of the ship down far enough to cause other damaged sections to flood as they are pushed under the waterline.
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Post by the light works on Sept 17, 2014 14:36:23 GMT
Eight sheets to the wind?... perhaps I need to explain better..... You steer the sails, to collect maximum wind. The rudder just controls the ships direction, if you have your sheets completely sideways to the wind, you aint going nowhere?... The point I am trying to make is the Chute idea will only work in certain directions, as in you wont be able to steer the ship past 45degree to direction of wind, as past that the chute will just be dragging the ship sideways, with a sail, you can get 90degree to the wind with ease... and further... The Chute will only be as useful as say a Spinnaker sail. Again, we are not trying a full mast of six sails here, just one solitary sail, kept "Open" and in shape, by the mast, and all the pull being dispersed by a good bit of rope at four corners (Or more...) to the deck, and strong tie-down points. The mast will ONLY be used to give shape to the sail. The thrust will be collected by the rigging. If you dont have strong enough tie down points for that, then I suggest you argument is self defeating, because where were you going to tie off your Chute anyway?.... Keel, yes, you may need one... but hang on, Destroyers have "Stabilisers" anyway dont they?... if this idea works and they are producing power, the stabilisers will be in use. Plus again, we aint trying to get the ship over like a racing yacht here, just getting some momentum that is better than sitting still. 10 knots is a lot better than none at all. Please note, I am not trying to be awkward or "Right" on this discussion, I am just arguing the other side of the discussion from what little I know about sailing.... as far as the hull and stabilizers - the stabilizers on a destroyer are intended to prevent high seas from creating an unstable firing platform. they do next to nothing to prevent the hull being pushed sideways - because they normally just compensate for any lateral drift by pushing the boat in the direction they want it to go. even with the knife hulls, my sailboat requires centerboards to prevent it being pushed sideways when sailing on a tack. Attachment Deletedit is one of those questions - if you have a cask of beer out in the wilderness and you want to get beer out of it, you can knock the bung out - or you can whittle a bar out of fallen trees and build a pressurized delivery system out of bicycle pumps and bamboo. if you have a destroyer and some parachutes and you want the destroyer to move through the water, the best option is to convert the parachutes into kites - a process that takes about 5 minutes - and fly them off the bow of the boat.
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Post by silverdragon on Sept 18, 2014 8:58:02 GMT
I can see both sides of the argument. But even with the "Kit" off the bow of the boat, why so high?.....
If you are "escaping" sending up a big "I am here" sign, is that wise?.....
To clear turbulence from superstructure, so, just higher than the top of the tallest bit.... Does that need a rocket launcher?...
And then, just where did they get a rocket launcher that can deploy a parachute?..... Of course, I carry on at all times in the boot of MY car, dont you all?.....
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