Sailing ships at TL3

[Fred Brackin]

Originally Posted by temp

1) With regards to all this discussion of which TL Clipper ships are, I am not sure that is the issue.
a)I used clipper ships for the math because I had decent data, thus they make a good example of how much power you can pull from a sailing rig. As near as I can make out from draw power, it is the amount of power in the machine, not how efficiently it outputs it, to what you can draw.
b) Has the TL chart been changed in 4th edition? In 3ed, (which are the books I own), basic pg 185, sidebar, Tech Levels - Transportation, 3. Sailing Ships 4. Fully-rigged ships 5. Steamships.
2) With regards to this business of "take-off points", if the ship was towing a barge that would otherwise be drifting, then the tow-rope would be a take off point and thus a suitable target for the spell? Seems physically odd, the barge starts slowing down, while the ship continues, and the rope does what? Magically stretches? This would boggle me much worse than David Johnson2's sailing ship immobilization effect...

Ooo-kay, let's actually talk about sailing ships the way Mr. Hackard wants us to. :)

We'll start with b) and yes small changes have been made in the TL chart and the start date of TL5 moved forward to 1730 as I said. Clipper ships are also a later development than the "full-rigged" ship with every thing a full rig has and more courses of sails and "stu'n'sails" and a longer leaner hull too. they really are TL5.

In fact they're basically the ultimate development of sailing ships and a thing which applied to them could be so much reduced in a TL3 sailing ship that it fell below any point of significance. At just a guess a clipper ship had 20x as much sail area as a TL3 round ship. It's certainly a huge advantage for the later ship.

[David Johnston2]

Originally Posted by temp

1) With regards to all this discussion of which TL Clipper ships are, I am not sure that is the issue.
a)I used clipper ships for the math because I had decent data, thus they make a good example of how much power you can pull from a sailing rig. As near as I can make out from draw power, it is the amount of power in the machine, not how efficiently it outputs it, to what you can draw.
b) Has the TL chart been changed in 4th edition? In 3ed, (which are the books I own), basic pg 185, sidebar, Tech Levels - Transportation, 3. Sailing Ships 4. Fully-rigged ships 5. Steamships.
2) With regards to this business of "take-off points", if the ship was towing a barge that would otherwise be drifting, then the tow-rope would be a take off point and thus a suitable target for the spell? Seems physically odd, the barge starts slowing down, while the ship continues, and the rope does what? Magically stretches? This would boggle me much worse than David Johnson2's sailing ship immobilization effect...

No. It breaks. Or would if that qualified. The reason it doesn't is because it isn't moving the barge in a different direction from the way the wind is going the way a windmill would.

As to the TL chart, that's a quick reference guide. Fully rigged ships don't stop existing and being improved at TL5 just as the internal combustion engine didn't stop existing at TL 7. We have better internal combustion engines now.

That being said it wouldn't matter for your purposes because clippers wouldn't really generate much more force than the largest fully rigged ships of the previous tech level. The refinements had more to do with reducing drag. The real problem as I said, is that the machine would have to change the direction of motion (or convert it into something like electricity or visible light).

[roguebfl]

Originally Posted by David Johnston2

The real problem as I said, is that the machine would have to change the direction of motion (or convert it into something like electricity or visible light).

The whole point of triangle sail rigged ships is to change the direction of the motion, hence why they can sail in every direct except directly into the wind. If they didn't chnage the diraction the could only sail down wind

[temp]

As to what sailing ships at TL<5 can be, I submit, https://en.wikipedia.org/wiki/Chinese_treasure_ship
China in the 15th century. It's below TL 5, as they lost badly when the europeans showed up... I don't believe that something that size is are giving up a lot in terms of sail area to a clipper - overall weight of ship, yes, but that's not the issue... (some estimates say 2000 tons of cargo, which is to say a mid-sized clipper ship on board!).

I agree with David Johnson2 that sailing ships have advanced far beyond TL5, see these for a TL7 example , https://www.wired.com/2017/02/oracle...cas-cup-yacht/ .

[roguebfl]

Originally Posted by temp

I agree with David Johnson2 that sailing ships have advanced far beyond TL5, see these for a TL7 example , https://www.wired.com/2017/02/oracle...cas-cup-yacht/ .

The america's cup yachts are cutting edge TL8, that one of the other changes to the 4e tech levels, is the current modern age is TL8 not TL7. They spend fortunes and get every edge the rules allow in that particular race

[temp]

Originally Posted by roguebfl

The whole point of triangle sail rigged ships is to change the direction of the motion, hence why they can sail in every direct except directly into the wind. If they didn't chnage the diraction the could only sail down wind

And in real world terms, you take care of that little into the wind problem with a technique called tacking...You can in fact effectively move due north, with the wind blowing due south.

[whswhs]

Originally Posted by temp

And in real world terms, you take care of that little into the wind problem with a technique called tacking...You can in fact effectively move due north, with the wind blowing due south.

That's what the triangle rig is for; it tacks more efficiently than a square rig does.

But even then, you can't sail straight upwind. What you do is zigzag across the wind, covering significant extra distance, and thus making less speed than if you were sailing, say, perpendicular to the wind.

[roguebfl]

Originally Posted by temp

And in real world terms, you take care of that little into the wind problem with a technique called tacking...You can in fact effectively move due north, with the wind blowing due south.

for those that don't know, tacking is sailing at slight angle to up wind, the "tacking" to change to a mirror angle, so you end up zig-zaging up your true course. This is was regatta racing typically use a triangle course so that at leas one leg regardless the time of the day (hence changing wind direction) everyone has to deal with a slower tacking leg.

[temp]

Originally Posted by whswhs

That's what the triangle rig is for; it tacks more efficiently than a square rig does.

But even then, you can't sail straight upwind. What you do is zigzag across the wind, covering significant extra distance, and thus making less speed than if you were sailing, say, perpendicular to the wind.

And just about every mechanical advantage system, gears, levers, transmisions, etc, changes scale/speed of movement for force... what's your point. You taking a natural source of kinetic energy and re-purposing it to act by moving you, your cargo, and your machine (boat) in whatever direction you want...

[roguebfl]

Originally Posted by temp

And just about every mechanical advantage system, gears, levers, transmisions, etc, changes scale/speed of movement for force... what's your point. You taking a natural source of kinetic energy and re-purposing it to act by moving you, your cargo, and your machine (boat) in whatever direction you want...

Remebr the Wedge is one the 6 classical simple machines, which "functions by converting a force applied to its blunt end into forces perpendicular (normal) to its inclined surfaces."

a sail function takes the wind forces perpendicular to the sail converting it onto force parallel to the bow/keel