Speeding up a sailing ship with planar bound huge air elemental.

The party is currently travelling on a ship. The journey is taking too long and they want to speed it up. The Wizard decides to clear a part of the main deck between the masts, draws a summoning circle, then casts Tongues to speak Auran and finally casts Planar Binding to conjure a Huge Air Elemental. He commands it to "without damaging this ship and without blowing anyone or anything overboard, I command you to make this ship go faster in the direction and for the duration dictated by me".

Air elementals have no ability to cast gust of wind or anything like that at will, but it makes sense that a big air elemental could make enough wind to move a ship. I rather like the idea of an air elemental blowing in the ship's sails and if it worked, it would mean always getting good wind and always from the back of the ship.

I assume that the captain can be placated, and a heated argument between party and ship crew is not a problem here. I also know that journeys are usually hand-waved by the GM and when there is a lull, it happens for story-related reasons and this is also not part of my question.

So:
1) Would it work? What would be the bonus to charisma check, assuming nothing is offered to the elemental? This task is not against the nature of the elemental, but probably not fun enough to grant a bonus on opposed charisma test.

2) Would a water elemental work better or just as well? Would planar binding something else work even better?

3) The silver for the summoning circle has no cost, but silver costs around 5gp per pound, so would assuming 25 gp cost for the circle be reasonable?

4) What could go wrong with this plan? I think on failure the Elemental would just leave or perform a single Whrilwind attack, possibly throwing someone overboard, and then leave. Maybe the presence of all that air and water around the ship would make controlling elementals more difficult. Would a room below deck be better for binding? Less air and less chance to disrupt the circle during the rest of the journey, but also not enough room for the whole elemental.

is the air elemental on the ship or in the water cuz if its on the ship no matter how much wind it makes it wont make the ship move

is the air elemental on the ship or in the water cuz if its on the ship no matter how much wind it makes it wont make the ship move

O RLY?

Lady-J wrote:

is the air elemental on the ship or in the water cuz if its on the ship no matter how much wind it makes it wont make the ship move

O RLY?

each action has an equal and opposite reaction if the elemental is on the boat blowing wind into the sails the boat wont go any were as the elemental will equally be pushing the boat backwards from the force he is exerting, if the elemental blows the other way they are negating the natural wind going into the sails and not gaining any speed, if they take the sails down and the elemental blows behind them they will probably just move at the same speed that they were going in the 1st place, however if the elemental is off the boat then the only force they will be exerting will be to move the ship forward and not have any of their force holding the ship back

is the air elemental on the ship or in the water cuz if its on the ship no matter how much wind it makes it wont make the ship move

It is an air elemental, it flies. The elemental is first planar bound on the ship, but once it agrees to perform forced labour, it is supposed to fly behind the ship and push it. Also, this is Pathfinder/DnD, so Newtonian physics doesn't fully apply :)

I find the thought of ship sailing fast with a "Deja vu" music in the background hilarious :)

I suppose if this worked, it might have some practical applications for expensive and fast spoiling cargo and the like (VIPs would probably rather use teleportation). Bonus points when pirates see that something weird is going on with this ship and avoid it like if it was plagued :)

Lady-J wrote:

is the air elemental on the ship or in the water cuz if its on the ship no matter how much wind it makes it wont make the ship move

It is an air elemental, it flies. The elemental is first planar bound on the ship, but once it agrees to perform forced labour, it is supposed to fly behind the ship and push it. Also, this is Pathfinder/DnD, so Newtonian physics doesn't fully apply :)

I find the thought of ship sailing fast with a "Deja vu" music in the background hilarious :)

I suppose if this worked, it might have some practical applications for expensive and fast spoiling cargo and the like (VIPs would probably rather use teleportation). Bonus points when pirates see that something weird is going on with this ship and avoid it like if it was plagued :)

would have it need a full round action to blow into the sails then need to spend a round flying to the new location of the boat, whirlwind special ability most likely wouldn't work as its wind force in a tornado pattern so it would just move the ship around in circles

If you like the idea then let it work, rule of kewl

blahpers wrote:

Lady-J wrote:

is the air elemental on the ship or in the water cuz if its on the ship no matter how much wind it makes it wont make the ship move

O RLY?

each action has an equal and opposite reaction if the elemental is on the boat blowing wind into the sails the boat wont go any were as the elemental will equally be pushing the boat backwards from the force he is exerting, if the elemental blows the other way they are negating the natural wind going into the sails and not gaining any speed, if they take the sails down and the elemental blows behind them they will probably just move at the same speed that they were going in the 1st place, however if the elemental is off the boat then the only force they will be exerting will be to move the ship forward and not have any of their force holding the ship back

Did you follow my link?

Lady-J wrote:

blahpers wrote:

Lady-J wrote:

is the air elemental on the ship or in the water cuz if its on the ship no matter how much wind it makes it wont make the ship move

O RLY?

each action has an equal and opposite reaction if the elemental is on the boat blowing wind into the sails the boat wont go any were as the elemental will equally be pushing the boat backwards from the force he is exerting, if the elemental blows the other way they are negating the natural wind going into the sails and not gaining any speed, if they take the sails down and the elemental blows behind them they will probably just move at the same speed that they were going in the 1st place, however if the elemental is off the boat then the only force they will be exerting will be to move the ship forward and not have any of their force holding the ship back

Did you follow my link?

i am aware of boats that have fans on them they are also light weight and only support a small number of people and if they were to use the elemental like that on the boat they would be going slower-maybe the same speed as they would with the sails but definitely not faster

True, but the principle is that you can propel a boat with sufficient wind blown behind you. If the boat is constructed with that in mind and the OP captures a sufficiently strong directional wind generator, the ship will move.

A regular old air elemental, however old, won't suffice. You'd need something capable of generating ridiculous amounts of directional wind. I don't know of an outsider that would suffice off the top of my head. You're probably better off with a magic item that can control the weather, like an orb of storms. It's not as fancy, but it's more reliable.

I bet an Anemos could do it.

I would allow it, either with an Air or Water Elemental. Either the Air Elemental is 'pushing' the ship or sails (not enough to rip them off) from the air or the water elemental is pushing from behind the ship. This is likely considered a simple command, not dangerous (unless you were traveling through some really strange water), so I doubt you'd fail to convince the creature.

Deciding how fast they move depends on the size and weight of the boat. It would probably depend on the creature's Strength and modified for its Huge size (Water elemental is just a bit stronger than an air elemental, so that's probably a better choice for this task.) Assume that as long as it's within the heavy load of the creature, it can move the ship reasonably. Wind or water currents or additional rowing might enhance or alter this. If the ship is heavier, the creature might be able to drag it at 5x max load, but then it's basically just moving 5 feet per round anyway, so unless you're trying to get off a sandbar or out of a current, you're gonna need a stronger (or multiple) creature.

I would allow it, either with an Air or Water Elemental. Either the Air Elemental is 'pushing' the ship or sails (not enough to rip them off) from the air or the water elemental is pushing from behind the ship. This is likely considered a simple command, not dangerous (unless you were traveling through some really strange water), so I doubt you'd fail to convince the creature.

Deciding how fast they move depends on the size and weight of the boat. It would probably depend on the creature's Strength and modified for its Huge size (Water elemental is just a bit stronger than an air elemental, so that's probably a better choice for this task.) Assume that as long as it's within the heavy load of the creature, it can move the ship reasonably. Wind or water currents or additional rowing might enhance or alter this. If the ship is heavier, the creature might be able to drag it at 5x max load, but then it's basically just moving 5 feet per round anyway, so unless you're trying to get off a sandbar or out of a current, you're gonna need a stronger (or multiple) creature.

Problem is, an air elemental can't actually generate directional wind at all, much less with enough power. You'd need something like the anemos Chromantic Durgon <3 mentioned, which is basically control winds with feet.

Problem is, an air elemental can't actually generate directional wind at all, much less with enough power. You'd need something like the anemos Chromantic Durgon <3 mentioned, which is basically control winds with feet.

My example wasn't about 'blowing' it was basically just pushing, either by billowing into the sails (like a harness on a mule pulling a plow) or pushing against the back of the ship. I understand the OP wanted the air elemental to be flying behind puffing it's cheeks, my answer was just about how the elementals would actually work for purposes of accomplishing the task.

My name got bolded
I feel special

blahpers wrote:

Problem is, an air elemental can't actually generate directional wind at all, much less with enough power. You'd need something like the anemos Chromantic Durgon <3 mentioned, which is basically control winds with feet.

My example wasn't about 'blowing' it was basically just pushing, either by billowing into the sails (like a harness on a mule pulling a plow) or pushing against the back of the ship. I understand the OP wanted the air elemental to be flying behind puffing it's cheeks, my answer was just about how the elementals would actually work for purposes of accomplishing the task.

Pushing the sails would run into the physics problem Lady J mentioned earlier. I guess it could just back up and ram the sails over and over, but unless it has a lot more mass than I'd expect a creature made of living air to have, it's gonna take a while.

A Huge Air Elemental has a 22 strength. Under favorable conditions, that would allow it to drag around 2.5 tons as a heavy load. It could drag such a load at a top speed of 225' per round.

By flying into a ship's sails, I would allow an air elemental to increase a ship's speed by (225'/round) x (2.5 tons/ship's tonnage), up to a max speed of 300'/round.

Wikipedia/Google will give you the approximate tonnage of various historical ships. A two-masted ship might weigh around 50 tons, so with this system your party's bound elemental could speed it up by 10'/round--that's a little more than 1 MPH, 27 miles more each day. Which could cut quite a lot of time off of long voyages--transatlantic crossings took about six weeks, back in the days of wind power.

A Huge Air Elemental has a 22 strength. Under favorable conditions, that would allow it to drag around 2.5 tons as a heavy load. It could drag such a load at a top speed of 225' per round.

By flying into a ship's sails, I would allow an air elemental to increase a ship's speed by (225'/round) x (2.5 tons/ship's tonnage), up to a max speed of 300'/round.

I am getting 520 for a heavy load at 22 Str, x4 for Huge to 2,080 (about 1 ton), then x5 for dragging, which would let him drag about 10,000 pounds-ish or 5 tons.

Since his Fly speed is 100, at a heavy load, his speed would drop to 70 (which it would have been at medium load) meaning it could move 140 feet (28 square) per round as a double move.. If he were dragging (anything above his heavy load), his speed would only be about 5 feet per round (full round action) and he'd be without his Dex AC (that's the penalty for lifting up to 2x weight, dragging is a much higher weight, so I don't see that the penalties would be different). The 5 foot distance can be modified by favorable or unfavorable conditions (wind speed and direction, currents, etc.) Dragging it probably won't add too much to the current speed of the ship, though it can help in the short term, pulling off a shoal (carefully) or out of a Sargasso field or adverse current or whirlpool.

So basically if their ship is over 1 ton, then you will need multiple elementals or you will only be going 5 feet per round (prevailing winds notwithstanding) up to 5 tons. At least, if my math is right.

I second rule of cool on this one. The idea that an air elemental can be used to propel a ship is so fantasy tropey that not letting it happen starts to interfere with suspension of disbelief.

Let your players have this, have some aspect of whatever they're doing work out favorably for them because they got where they were going earlier and be glad they aren't just teleporting around and forgoing travel adventures at all.

It is very rare that me and Ryan Freire agree on a thing! Rule of Kewl folks! its g#* d+$n unifying.

I am getting 520 for a heavy load at 22 Str, x4 for Huge to 2,080 (about 1 ton), then x5 for dragging, which would let him drag about 10,000 pounds-ish or 5 tons.

Since his Fly speed is 100, at a heavy load, his speed would drop to 70 (which it would have been at medium load) meaning it could move 140 feet (28 square) per round as a double move.. If he were dragging (anything above his heavy load), his speed would only be about 5 feet per round (full round action) and he'd be without his Dex AC (that's the penalty for lifting up to 2x weight, dragging is a much higher weight, so I don't see that the penalties would be different). The 5 foot distance can be modified by favorable or unfavorable conditions (wind speed and direction, currents, etc.) Dragging it probably won't add too much to the current speed of the ship, though it can help in the short term, pulling off a shoal (carefully) or out of a Sargasso field or adverse current or whirlpool.

So basically if their ship is over 1 ton, then you will need multiple elementals or you will only be going 5 feet per round (prevailing winds notwithstanding) up to 5 tons. At least, if my math is right.

Whoops! I left the x4 for huge out of my calculations! The rules say that weight limits for dragging can double under favorable conditions. I'd say that pushing a hydrodynamic vessel over liquid qualifies. So, 520 x 4 (for huge) x 5 (for dragging) x 2 (favorable conditions) = about 10 tons. My bad.

With a heavy load, a run action gives x3 movement. 100' reduces to 75' at a heavy load. Thus, 225'/round.

I would not apply the 5'/round rule for carrying up to double carrying capacity over your head in this instance any more than I would apply it to a dog hauling a sled or a horse pulling a cart.

With the x4 correction, a 50 ton ship would go around 40'/round faster--that's an extra 5 mph, or 108 miles/day, a significant improvement.

Thanks guys. I especially like how you've come up with a way to calculate this.

As for Newton's laws, I simply assume that the Elementals can easily move in their native element while pushing or pulling an object and the "force applied the other way" is just air or water being pushed behind the ship and there is no need to worry about it. (And if you really hate inertia-less drives, DnD already has telekinesis, bull rush and other spells that don't exert "an equal and opposite reaction").

Greater Planar Binding to bind Elder Elementals would be really pushing it, because the bigger the elemental, the greater the chance it will break, leave, attack or just sit in the circle and be uncooperative. Still, I'll include them here.

Elder Air Elemental, 28 str, fly 100
1200 lbs max load, x4 for Huge, x5 for dragging, x2 favourable conditions is 48000 pounds or 21.77 tonnes.
100 ft speed is reduced to 70 ft, which is doubled for double move to 140 ft. (running would be x3, but I assume even Elementals can't run for days without getting tired).
So with the assumption that moving heavier things slows down the elemental proportionally, that 50 tonne boat is being pushed at 60 feet / 6 seconds, which is 6.8 mph or 163 miles per day.

Elder Water Elemental 30 swim 90
1600 lbs max load, x4 Huge, x5 pushing, x2 favourable conditions is 6400 pounds or 29 tonnes.
90 ft speed is reduced to 60 ft, which is doubled for double move to 120 ft. (running would be x3, but I assume even Elementals can't run for days without getting tired).
So with the assumption that moving heavier things slows down the elemental proportionally, that 50 tonne boat is being pushed at 69.6 feet / 6 seconds, which is 7.91 mph or 190 miles per day.

Therefore water elementals are a bit better, which makes sense.

Assuming the Wizard has 20 Int (reasonable, especially with a circlet of intellect +2), level 11 (minimum to cast level 6 spell) and 10 Charisma (dump stat, but the party may have a cloak of +2 charisma), these are the chances for success on planar binding a huge air elemental:

1) The elemental has a will saving throw to avoid being trapped. The only negative consequence of it passing this save is that the Wizard has to start over. HAE has +5 will saving throw and the DC is 10 + 6 + 5 = 21, so there is 30% chance the binding won't work, without further negative consequences.

2) The HAE has no spell resistance or teleport, but it can try to escape with a Charisma check. It pits it's 11 Charisma against DC 15 + 11/2 + 0 = 20. If it fails, it will try again each day. This part is actually dangerous, because when it escapes, it can perform a few attacks against the ship and crew before disappearing. It has 60% chance per day of escaping and possibly causing trouble, which makes this very risky.
EDIT: Charisma check is d20 + Cha modifier, so it has 5% chance of escaping, not 60%.

3) Before the Elemental starts the task, it has to be bargained with an opposed charisma check. The Wizard can have a +0 to +6 bonus, depending on what he offers, how intimidated the elemental is and how it hates the task. I'll use +0 because the Wizard isn't offering anything, they are surrounded by air and water, which makes the elemental more confident, but the task is agreeable. There is 45% chance that the Elemental will agree to perform the service. Otherwise the Wizard should probably just dismiss it or it will sit there until next day, when escape attempt and bargaining start over. It won't hurt anyone while captured, but it will scare the crew. I think once the Elemental agrees to the task, it will stop trying to escape with Charisma check, but will only remain in service for up to 11 days (caster level).

Heh, Sorcerers are inherently better at Planar Binding than Wizards because of all those Charisma-based checks.

And random encounters be damned, if pirates or aquatic lifeforms see a huge squid made of water pulling a ship or a tornado pushing it, they're not going to mess with that thing :) Navy might attempt to "help" though, which could lead to a role-playing opportunity.

Finally, spells like control weather or control winds could be better suited for this (and much less dangerous), but they're so situational that Wizards and Sorcerers rarely bother with them, while Planar Binding is all-around useful for other things too.

Minor nitpick:

2) The HAE has no spell resistance or teleport, but it can try to escape with a Charisma check. It pits it's 11 Charisma against DC 15 + 11/2 + 0 = 20. If it fails, it will try again each day. This part is actually dangerous, because when it escapes, it can perform a few attacks against the ship and crew before disappearing. It has 60% chance per day of escaping and possibly causing trouble, which makes this very risky.

Because the elemental has 11 CHA, it has a +0 modifier, meaning it has to roll a mat 20 to escape-which it could anyway. So it has closer to a 5% chance of escaping each day.

While the math done here is a really solid start. There is one thing that people are forgetting. Creatures can't run(or even double move) indefinitely, unless they are also immune to fatigue and such. They can't even travel more than 8h a day without forced march checks. Granted a party that has access to planar binding or greater, will have options to handle such conditions as well. Though for the most part running is not gonna happen for any length of time.(can come in handy in naval battle though)

While the math done here is a really solid start. There is one thing that people are forgetting. Creatures can't run(or even double move) indefinitely, unless they are also immune to fatigue and such. They can't even travel more than 8h a day without forced march checks. Granted a party that has access to planar binding or greater, will have options to handle such conditions as well. Though for the most part running is not gonna happen for any length of time.(can come in handy in naval battle though)

Immunity to bleed, paralysis, poison, sleep effects, and stunning.

Not subject to critical hits or flanking. Does not take additional damage from precision-based attacks, such as sneak attack.
Proficient with natural weapons only, unless generally humanoid in form, in which case proficient with all simple weapons and any weapons mentioned in its entry.
Proficient with whatever type of armor (light, medium, or heavy) it is described as wearing, as well as all lighter types. Elementals not indicated as wearing armor are not proficient with armor. Elementals are proficient with shields if they are proficient with any form of armor.
Elementals do not breathe, eat, or sleep.

This implies since they can't be put to sleep and do not sleep, they can't get tired in the first place (how would something made out of pure air get tired anyway? It doesn't have any muscles or organs to overtax or that produce waste).

Not being required to sleep does not mean not getting tired. There is no immunity to fatigue or exhausted. I did check the subtype before posting.

Aren't game mechanics wonderful ...

Another vote for seems cool, seems very fantasy like, ought to work to some degree, create rules as needed as per the rule you are the GM, have fun.

IIRC, Elric of Melniboné uses this exact trick to speed up the fleet that sacks Imrryr -- when he finds that one air elemental isn't pushing his own ship fast enough to escape, he puts them all in his sails and abandons the other ships to their fate.

Moorcock's Elric is cited in the fundamental literature of the game, all the way back to Gygax's Appendix N. If the iconic things he does cannot be replicated in Pathfinder, the game is poorer for it, IMHO.

EDIT: Found a polar diagram for winds speed & direction vs. sailing ship speeds. If we simply treat a Huge air elemental (Spd 100 ft.) as a 10 mph favorable wind, a 1-ton ship gets 9 mph (90 ft./round) from that, even if there is no ambient wind. (Granted, a caravel is a lot bigger than 1 ton, but notice that the half-ton ship is slower, not faster, for the same wind speed & direction, so the relationship is far from linear.)

IIRC, Elric of Melniboné uses this exact trick to speed up the fleet that sacks Imrryr -- when he finds that one air elemental isn't pushing his own ship fast enough to escape, he puts them all in his sails and abandons the other ships to their fate.

Moorcock's Elric is cited in the fundamental literature of the game, all the way back to Gygax's Appendix N. If the iconic things he does cannot be replicated in Pathfinder, the game is poorer for it, IMHO.

EDIT: Found a polar diagram for winds speed & direction vs. sailing ship speeds. If we simply treat a Huge air elemental (Spd 100 ft.) as a 10 mph favorable wind, a 1-ton ship gets 9 mph (90 ft./round) from that, even if there is no ambient wind. (Granted, a caravel is a lot bigger than 1 ton, but notice that the half-ton ship is slower, not faster, for the same wind speed & direction, so the relationship is far from linear.)

Generally because small ships can really only take so much wind before they get capsized and large ships have larger sails so eventually momentum gets them going AND they can take more wind than smaller vessels.

Either way, no one looks back on their game where they summoned an elemental in order to get Elemental speed/X +base speed of ship bonus movement per round fondly. They might look back on the game where they summoned an elemental and it bought them a step against whatever enemy they were working against fondly though.

Either way, no one looks back on their game where they summoned an elemental in order to get Elemental speed/X +base speed of ship bonus movement per round fondly. They might look back on the game where they summoned an elemental and it bought them a step against whatever enemy they were working against fondly though.

I think you're far too quick to assign your own preferences to everyone else. The very existence of this thread implies that your assertions regarding what "no one" wants are erroneous.

I also know that journeys are usually hand-waved by the GM and when there is a lull, it happens for story-related reasons and this is also not part of my question.

I think this is an important question, though. If journeys happen at the speed of plot, all PCs should be dwarves, and no one should play a ranger. In that case, of course ship speeds don't matter -- speeds don't matter, period. If that's the kind of game the group wants, fine, but in my home game we track movement speeds and journey speeds, and a group that's too slow might end up getting somewhere too late.

Ryan Freire wrote:

Either way, no one looks back on their game where they summoned an elemental in order to get Elemental speed/X +base speed of ship bonus movement per round fondly. They might look back on the game where they summoned an elemental and it bought them a step against whatever enemy they were working against fondly though.

I think you're far too quick to assign your own preferences to everyone else. The very existence of this thread implies that your assertions regarding what "no one" wants are erroneous.

No the existence of this thread implies that there are a lot of people who enjoy crunching numbers and arguing about rules interactions on a forum. Not that there are a lot of people who enjoy doing that math mid game to figure out travel times from adventure to adventure. Nor that there are a lot of people who carry the memory they did a bunch of math to figure that out fondly as they reminisce about Pathfinder games they've played.

If in the campaign ships are just journey enabling plot devices, then rule of cool certainly suffices and I'd let it go at that.

The problem with 'rule of cool' though, is that what is cool and fun once, can become a major issue, as well as totally uncool and distracting when repeated ad nauseum, which is likely to happen if the cool thing adds too much of an advantage.

In this case, that is only likely to happen if ship-to-ship combat is going to be featured in your campaign, but if it is you are likely going to have to actually tighten up the rules effects for this, and make sure it isn't unbalancing.

No the existence of this thread implies that there are a lot of people who enjoy crunching numbers and arguing about rules interactions on a forum. Not that there are a lot of people who enjoy doing that math mid game to figure out travel times from adventure to adventure. Nor that there are a lot of people who carry the memory they did a bunch of math to figure that out fondly as they reminisce about Pathfinder games they've played.

I think you're far too quick to assign your own preferences to everyone else.

I still think that. Your preferences are not universal. You don't get to tell everyone else what they want.

Is consulting polar charts mid-game too much? Maybe so, depending on the participants (I've gamed with people who would have loved it). But being able to make tactical decisions about stuff other than direct combat -- and have those decisions actually matter -- is important to some groups, if not to yours.

Yes and I think that forum communities tend to vastly overestimate the way their preferences are distributed. What do we have, 35 posts 80% of which are from the same half dozen people? The OP even mentions that the air elemental is being summoned because the journey is taking too long and they want to speed it up.

So really, thats the important thing. The players feel their game is lagging and are willing to burn the gold on a planar binding to wrap this travel time up B.

Which camp do you suppose those players belong to?

Edit: for another productive answer, I'm assuming they're in a sailing ship. Maybe treat them as a Galley or longship being rowed and sailing and use the chart on this page

OK guys, it was a hypothetical question. I got that idea before going to sleep and wanted to ask if it would work. I found it amusing to try and pull this stuff on a GM when travelling by ship. Maybe even make it amusing for other party members "You wake up from your nap and hear loud noises upstairs. As you ascend to the main deck, you see a 10 metre tall tornado in the middle of the ship and there is a sparkling circle below it. Your wizard is screaming like a man possessed in some unknown language and making threatening gestures at the tornado, while the captain is yelling death threats at the Wizard. The crew runs around like headless chickens and some stuff is being blown around by strong winds. What do?"

On the plus side, this thread gave me a better grasp of how Planar Binding is supposed to work, because after reading it, I found it wordy and confusing.

I do like the idea of tracking travel time and distance as well as food and doing Survival rolls on land and some kind of weather rolls on a ship. To most people this is much less exciting than hand-waving the journey as having exactly one random encounter before getting to the dungeon proper. The kind of slow-paced exploration I'm describing would be kinda fun at low levels, but by the time the party has a lvl 11 Wizard, they have spells to fly over chasms and rivers, create food and water, create magical shelter and generally make challenging terrain irrelevant.

The crunch answer seems to be that a single Huge Air Elemental would help a little, but would not be amazing. It would still work for 8 hours per day (or continuously, depending on GM ruling on Exhaustion) and add at least 1.5 mph (assuming no running, and no double move) to a 50-ton ship. It is enough to make a difference during escape from a similar class ship or to get out of a windless zone and should even shorten a long journey by a day or two. For anything amazing and memorable, multiple Elder Elementals would be needed, but it would at least look cool.

I assumed a sailing ship, not a galley. I assumed the party wants to go from city A to port B and buys passage on a merchant ship and those usually work better with sails. Rowboats can make pretty good ramming warhips, because while they have sails too, they don't depend on the wind during naval battles, but have less room for cargo and feeding all those rowers gets expensive.

While a water elemental would be stronger and faster, I think that binding an air elemental is safer. If it escapes, it will possibly attack some people or damage the railing, then go away. If it lingers, spells and ranged weapons can take care of it. An escaped and angry water elemental could drown some people by pulling them into the water and under, then sink in the sea after it takes some damage. From down there, it could trash the rudder and throw the ship at some coastal rocks, all with relative impunity, because water blocks most spells and would provide concealment, while PCs aren't usually geared for underwater combat (where ranged weapons are crap and the elemental has speed advantage anyway).

Thanks for the wind/sails chart, I didn't know that having wind at a slight angle and not directly from behind is best for speed.

I think the best thing for the GM to do when some complicated rules question comes up is to make a quick ruling that kinda makes sense, then look that up after the session and probably use the revised version in the future. Spending a lot of time looking up charts and weights and speeds during the session would just grind it to a halt.

You could make the ship lighter. Is mithral lighter than wood?

Given that mithral is half as dense as steel. No not even close as wood is far less dense than half of steel.

Now there are some metal parts on a ship but those would be miniscule part of the total tonnage.

Darkwood is what you'd probably use to make a ship lighter, since most are wooden and even those with metal hulls will still have a sizable amount of wood. It's half the weigh of normal wooden materials but you're adding 10 gp to the price of the ship per pound. Of course, since you're wanting to do it with mithril, I doubt price is what would be stopping you.

Darkwood is what you'd probably use to make a ship lighter, since most are wooden. It's half the weigh of normal wooden materials but you're adding 10 gp to the price of the ship per pound. Of course, since you're wanting to do it with mithril, I doubt price is what would be stopping you.

One of the problems with continually making a ship lighter is that eventually a strong wind just blows it over rather than pushes it along. Its why most ships have stones for ballast underneath the bottom deck.

One of the problems with continually making a ship lighter is that eventually a strong wind just blows it over rather than pushes it along. Its why most ships have stones for ballast underneath the bottom deck.

True, but there are other ways to increase stability as well. Attaching outriggers or extended keels, either along the bottom or extending at an angle from the hull beneath the waterline. Those wouldn't add a significant amount of weight (if wooden and using darkwood) compared to piling stones in.

Lol, a Katamaran (a ship with two thin hulls, connected by a large deck in between them) would be lighter, but I was assuming a normal merchant ship that people just happended to buy passage on. So nothing fancy like Darkwood or anything.