Sailing ships at TL3

[whswhs]

Originally Posted by roguebfl

hence the word "effectively" meaning in context while not directly moving in that direction that is your over all movement direction.

If that's the meaning you take "effectively" to have, then yes.

[Celjabba]

There are -today- supertanker and container ships that uses or plan to uses wind power to assist propulsion. Kite sail are in use, Flettner Rotor either on trial or in use.

The "stop the ship dead in water" is not a problem, it would be the same if using draw power on a diesel ship engines.

The change direction is also imho not relevant.

The way I see the spell, you can use it if you have a way to hook the power source to an arbitrary device. The spell become/suppleant that device.
A sail ship doesn't really qualify imho, it moves itself but you cannot use his sails to move something else, the ship itself staying in place.

[Tomsdad]

Originally Posted by whswhs

If that's the meaning you take "effectively" to have, then yes.

Ultimately I think the point is in terms of the topic at hand, a sail boat is a "machine" that is not limited to only move in the direction of the wind, but can sail off the wind.

I.e it uses a mechanism to covert the energy of the wind into thrust that can be applied in a different direction from that of the wind. Now weather or not that's enough mechanism to satisfy the spell I'm not sure, it's not really my area

[Tomsdad]

Originally Posted by David Johnston2

There is an inherent problem with this analysis quite apart from clippers being TL 5 sailing ships. (Clippers were not clearly inferior to steam ships. They were actually very competitive). You can't simultaneously get magic and electricity out of the same dynamo using the spell. The spell is converting the output into magic. The use of this spell to immobilize sailing ships while the wind blows would be just...goofy.

Actually if you doing this to generate magical energy is that a problem? In fact if I can safely moor up all my boats in a harbour, or on a sea anchor or even on a lake and have them stay at full sail and generate energy like this and have them stay still that would make life easy! Obviously I can't use them to go anywhere when they are used like this, but then that means I can in theory design boats that are specifically good at meeting the spells requirements without having to compromise with the needs of seaworthiness or capacity.

[AlexanderHowl]

But a sailboat is not a machine in GURPS because it is an unpowered vehicle (Supers, p. 106, the Mechanical Hierarchy).

[Ulzgoroth]

Originally Posted by Celjabba

The "stop the ship dead in water" is not a problem, it would be the same if using draw power on a diesel ship engines.

No, it wouldn't. If you use Draw Power on a ship's engine, the ship's propellers will stop and it will drift to a halt from drag. But the spell won't do anything to the ship's motion directly, which it would have to to draw power from a sailboat.

(...drawing power from a rotating shaft seems a bit goofy on its own, since the power generating bit doesn't actually work if the shaft isn't rotating, and if the shaft is rotating downstream devices can use that...)

[Tomsdad]

Originally Posted by AlexanderHowl

But a sailboat is not a machine in GURPS because it is an unpowered vehicle (Supers, p. 106, the Mechanical Hierarchy).

Well I have to say I'm not that up on this spell (or the Mechanical hierarchy), so if sailboats are disqualified by dint of being in GURPS terms terms unpowered vehicles, then cool. It's just there seems to be some debate on this

But then the debate seems to be based on some pretty precise distinctions!

[Tomsdad]

Originally Posted by Ulzgoroth

No, it wouldn't. If you use Draw Power on a ship's engine, the ship's propellers will stop and it will drift to a halt from drag. But the spell won't do anything to the ship's motion directly, which it would have to to draw power from a sailboat.

(...drawing power from a rotating shaft seems a bit goofy on its own, since the power generating bit doesn't actually work if the shaft isn't rotating, and if the shaft is rotating downstream devices can use that...)

Wouldn't the equivilent be removing the impetus derived from the sail, and the sail boat like the propelled boat would slow to a halt*?

Similarly if you furl your sails your boat doesn't come to a instant and complete stop any more than a boat that switches off it's propeller.


*well subject to the wind and water acting directly on the hull of course

[roguebfl]

Originally Posted by Tomsdad

Well I have to say I'm not that up on this spell (or the Mechanical hierarchy), so if sailboats are disqualified by dint of being in GURPS unpowered vehicles. than cool. It's just there seems to be some debate on this

But then the debate seems to be based on some pretty precise distinctions!

The sole point of the restriction of the spell is the Spell is in the Technology Collage and it was thematically inappropriate to use the spell directly on natural forces, but instead its meant to merge technology with magic. And sail boat is way more technology involved in that many of the thing people don't bat their eye at use this spell on. It makes less seances to be quibbling over why type of machine it is when and your kidding yourself it not a machine is when a Slope and Wedge have been considered machines siance the founding of physics. the have zero problem recognize the thematic limitation of the staff spell when it get in the way of fiction artctyl of a sword wielding wizard.

A sailing bow harnesses natural energy (wind) to do use full work (transport passengers and cargo) it is a technology based machine. a technology more over of key importantce in the history of techlnoly it only been over showed by electricity and gunpowder in how it has shaped the modern world.

[Fred Brackin]

Originally Posted by Tomsdad

But then the debate seems to be based on some pretty precise distinctions!

The definition that applies to this spell is that the power to be drawn upon must be in a form that would be usable to a machine. At TL6 this usually means mechanical power or electrical power.

It can't just be "energy" whether that be kinetic energy of a vehicle's motion, the thermal energy of a fire or several other things. It isn't the energy that's the important part it's the "in a form usable by a machine" that is.

It might be illuminating to look at Draw Power's predecessor Spell, Lend Power. If you wanted your sailing ship to go faster could you cast Lend Power on it? No, the spell for that is Propel. That would make your ship go faster even if there was no wind at all.