TheRPGSite

The Agarthanians transport cargo across a dried out salt sea with cargo sail wagons like this:

[ATTACH=CONFIG]1030[/ATTACH]

Who builds their wheels?

Quote from: Headless;966320Who builds their wheels?

The Agarthanians build them themselves, I guess. Why do you ask?

Here's some info on land sailing.

https://en.wikipedia.org/wiki/Land_sailing

I like the idea, especially for Dark Sun, and I want to run some combats!

Here's one in action:
https://www.youtube.com/watch?v=97fjOmGg2jc

Quote from: Pyromancer;966321The Agarthanians build them themselves, I guess. Why do you ask?

Cause if they neex somevone else to build them then they have have a relationship.  

As it is I'm not sure what to do with them.

I notice you put the steerable wheel in back.  Very smart, WAY more stable than the wheel in front design.

Quote from: Headless;966334Cause if they neex somevone else to build them then they have have a relationship.  

As it is I'm not sure what to do with them.

That's the way my worldbuilding works. I get hung up on ONE detail, in this case the sail wagons. :)

But a little bit of background:

Agarthi was once a powerful empire, its center located under the Gobi desert is. It was ruled by a race of snake people, but with a few humans in the "middle management", and lots and lots of human slaves. The reasons are unknown, but one day all the snake people retreated to the underground part of their kingdom and sealed all the entrances, leaving the humans stranded on the surface. Under pressure from surrounding human barbarians, the Agarthi retreated to their core land, mighty mountain fortresses in the Gobi desert, where they remain - mostly unknown - until today (today = 1245AD).

They trade with human settlements at the edge of the desert (gold and diamonds for food and slaves, mostly), and from time to time man one of their smaller fortresses there and use them as trade posts.

There is a centuries old struggle between the faction that wants to remain in the desert and await the return of their snake masters, and the faction that want to "abandon the old ways" and conquer a little bit of more hospitable land, with smaller factions siding with one or the other as they can gain politically from it. But the argument has become more heated, and a few "suspicious deaths" among powerful figureheads have happened.

All of this is unknown in Karakorum, there are only a few unreliable rumors of a mighty kingdom in the desert. But there isn't much else to do, so Töregene Kathun sends out a small diplomatic mission, to locate and find this kingdom, establish contact, and - depending on what they find - demand submission and tribute, raid, or spy the defenses for future campaigns.

What do they transport that is valuable enough to pay extra for fast movement?  Like a lecture I heard at MIT on maglev; "nobody's going to pay to move coal at 300 mph."

Quote from: Gronan of Simmerya;966346What do they transport that is valuable enough to pay extra for fast movement?  Like a lecture I heard at MIT on maglev; "nobody's going to pay to move coal at 300 mph."

They don't have transport animals, and don't want to walk a few hundred kilometers across the desert.

And dusting off the old sail wagon every once in a while is way more convenient than caring for a herd of camels all year around.

Neat! I would give this the following stats in my new Earthdawn 4th edition Ship rules:

Agarthi Sailing Wagon
 
Speed: * (as sailing ship, base speed is 1/2 wind speed on Speed Step table, can be pushed by the crew)
Maneuverability: 4 (as maneuverable as a canoe or rowboat)
Armor Rating: 9
Wound Threshold:10
Derelict Rating: 94
Destroyed Rating: 123
Captain Rating: 3
Crew Rating: 2
Cargo (duari): 12/40 (a duari is a large barrel first made by the t'skrang lizard men trading houses, it can hold 300 pounds of rice or 36 gallons of water)

The Agarthi sailing wagon is a land vehicle rigged like a sailing ship, often seen at trading posts near the Gobi desert. These unwieldy vehicles work best on terrain with few obstacles, such as at the edges and flat areas of deserts or wastes, dried lake beds, or beaches at low tide. The largest of these sailing wagons are the size of 4 large horse drawn wagons, and may carry up to 40 duari (12,00 pounds/ 6 tons) of crew, passengers, and/or cargo. These wagons must make a Hazard test each turn when exposed to winds over 15 mph or when traveling faster than Speed step 9 (21+ mph) on rough terrain to see if they capsize.

Minimum Crew: 2 (Land Sailing)         Total Crew: 7 (Officers count as double)
[ ] Derelict [< 2, adrift]   
[ ] Skeleton Crew [>= 2, ½ Speed, -4 mod]
[ ] Competent Crew [>= 4]
[X] Crack Crew [>= 6, allows certain maneuvers]
[ ] Legendary Crew [>= 8, +2 mod]

Crew Roster (5 duari)
Officers (2, 2 duari):
Agarthi Captain (Rating 3)
Agarthi First Mate (Rating 3, Navigator, Quartermaster)
Deck Crew (3, 3 duari):
Agarthi land-sailors x3 (Rating 2)

Ram +4
Batteries (3 duari):
Starboard Bow (1): Ballista x1 (Step 17, arcs 1/2/3)
Port Bow (1): Ballista x1 (Step 17, arcs 5/6/1)
Ammunition: 20 spears

Notes: Crew Rations (3 weeks): 1 duari of rations, 3 duari of water. Various ammounts of trade cargo, slaves, etc.

I don't know the Earthdawn system, but this writeup looks nice.
Regarding weapons: I'm not sure yet what weapons my Agarthanians use. A military sail wagon would surely have a ram, and some ranged weapons. Agarthean warriors might have some kind of mystic "lightning rod" leftovers from their snake masters.

Thinking about military sail wagons: How do they fight?

1) Shooting
Nothing much to say about that. Ballistas wouldn't do much damage, and it would be difficult to hit with a catapult. On the other hand, you can't build the wagons much bigger than the cargo wagon, and they have a few critical points, so it could either be drawn out battles, or a lucky hit early on that decides the victor.

2) Ramming
I'm not sure how viable this would be. Ancient warships could use this tactic because they were powered by oars which made them very fast and maneuverable. Here, everyone is powered by wind. I think it will be done, but not the primary tactic.

3) Boarding
This could work, although a hard brake at the moment the enemies want to board you can ruin their day...

4) My favorite: Small, fast wagons, shaped like wedges, trying to drive under the bigger wagons to flip them over.
This seems very dangerous for the attacking wagon, but there's not much the defending wagon can do against it. They need the ground clearance. So they would be escorted by similar small wagons that try to drive them off.

Quote from: Pyromancer;966462Thinking about military sail wagons: How do they fight?

1) Shooting
Don't attack the wagon body. Attack the sails. Chain and bar shot were used in the Napoleonic period to take down rigging, sails, and masts. Something similar fired from a ballista sounds possible. Fire arrows and hurled fire pots would also work. Or take a tip from the Byzantines and mount Greek fire siphons on the war sail wagons.

2) Ramming
I don't see this as viable. A better tactic might be scythes on the wheels like some ancient chariots. Useful against infantry and possibly to attack the wheels of another sail wagon.

3) Boarding
If the wagons are large enough swinging on ropes like in a pirate movie sounds fun and at least as feasible as most of the tactics in Mad Max Fury Road (which is to say somewhere between not very and not at all, but once you are doing sail wagons your veering into gonzo territory anyway).

Poles could be used either to fend off enemy wagons trying to board or with hooks on the end, to catch enemy wagons. And if the wagons are large enough a version of a Roman corvus (spike ended boarding plank) could be entertainingly gonzo.

Quote4) My favorite: Small, fast wagons, shaped like wedges, trying to drive under the bigger wagons to flip them over.

I don't see this as very viable, but it fits into the Mad Max sort of gonzo tactics, even success sounds dangerous for the wedges.

5) Grapnel & anchor: another tactic would use grapnels and anchors. Hook a grapnel attached to an anchor onto an enemy wagon then toss the anchor overboard. The sudden drag could easily overturn the enemy sail wagon or cause it to crash.

6) Kites: the Chinese invented war kites. These could either be large enough to lift a single attacker or unmanned and equipped with fire pots that could be dropped on enemy wagons or the kites could have razor tails or razor lines to cut away enemy rigging or sails.

Quote from: Bren;9664671) Shooting
Don't attack the wagon body. Attack the sails. Chain and bar shot were used in the Napoleonic period to take down rigging, sails, and masts. Something similar fired from a ballista sounds possible. Fire arrows and hurled fire pots would also work. Or take a tip from the Byzantines and mount Greek fire siphons on the war sail wagons.

2) Ramming
I don't see this as viable. A better tactic might be scythes on the wheels like some ancient chariots. Useful against infantry and possibly to attack the wheels of another sail wagon.

3) Boarding
If the wagons are large enough swinging on ropes like in a pirate movie sounds fun and at least as feasible as most of the tactics in Mad Max Fury Road (which is to say somewhere between not very and not at all, but once you are doing sail wagons your veering into gonzo territory anyway).

Poles could be used either to fend off enemy wagons trying to board or with hooks on the end, to catch enemy wagons. And if the wagons are large enough a version of a Roman corvus (spike ended boarding plank) could be entertainingly gonzo.

I don't see this as very viable, but it fits into the Mad Max sort of gonzo tactics, even success sounds dangerous for the wedges.

5) Grapnel & anchor: another tactic would use grapnels and anchors. Hook a grapnel attached to an anchor onto an enemy wagon then toss the anchor overboard. The sudden drag could easily overturn the enemy sail wagon or cause it to crash.

6) Kites: the Chinese invented war kites. These could either be large enough to lift a single attacker or unmanned and equipped with fire pots that could be dropped on enemy wagons or the kites could have razor tails or razor lines to cut away enemy rigging or sails.

Cool idea. Nice images.

I think the designs would include stretching fabric to provide nice shaded areas for people and sun-sensitive cargo to rest in shade during the day.

I don't expect they would be used as "land galleys" in combat, at least not the same way sea galleys were used, unless there were some magic involved. Mainly because water allows floating ships to be heavier without so much friction, so sea galleys can have rowers to improve ramming speed and maneuver even against or without wind, etc. Without another power source or ability to control wind, both sides maneuvering to ram each other using sails seems improbable. You at least need tactics for what to do when the wind's going the wrong way, or there is little or no wind.

I also think these things would be quite valuable and wanted to keep in good running order, so I'd expect crashing them into things to not be the first choice tactic.

I think a natural use though would be to avoid the fatigue of desert travel. Wind wagons allow travel day and night (when there's wind) without fatigue, and with enough wind in the right direction, the speed to outrun footmen and/or do drive-by attacks. I'd think slings would be natural weapons, especially if convenient-sized rocks are plentiful in the desert. Otherwise, arrows, darts, javelins, long spears.

For land wagons going with the wind, I would expect poles and booms with wheel-entanglers, hooks, grapnels, and trying to shoot the drivers. I'd expect the designs that expect combat would have shielding panels for crew and driver, but drivers have to be able to see, and all weight added slows down the potential speed.

Thanks Pyromancer. I agree with a lot of the advice so far. I have had my head in ship-combat rules for the last few months and your post was inspiring.

One of my crazier ideas was a "walking wagon beast" (with fire cannon!) designed from Theo Jaansen's "strandbeest": https://www.youtube.com/watch?v=MYGJ9jrbpvg&feature=youtu.be&t=3m41s

I have a teaser of my proposed 4E rules up on the FasaGames.com site if anyone is interested. I basically had to re-create OSR mass-combat in order to get the feel I wanted (1 minute turns, morale, etc). http://www.fasagames.com/forum/viewtopic.php?f=10&t=294 :D I also went with Ballista for your wind wagon as, in Earthdawn, they are portrayed more as the roman style huge-crossbows (on a mount/stand) as swivel-gun. There are some other classic weapons in Earthdawn you could use for the magic stuff mentioned, like Dragon's Breath (the greek-fire thrower mentioned, Damage Step 17, area effect, fire hazard), or the Thunderbolt Thrower which you mentioned a take on:

QuoteThunderbolt Thrower
Crew: 2 (or 3, see text)
Damage step: 27 (causes Harried effect)
Short Range: 10-120 yards
Long Range: 121-240 yards
Base Cost: 3,000 Silver
Weight: 75 pounds / 4 per duari (no ammunition required)
Pioneered on troll drakkars during the Second Theran War, thunder bolt throwers are large hardwood rods tipped with living crystal wrapped in a copper and orichalcum wire mesh, which glows with blue light when fully charged. They grant a huge boost to the ship’s effective firepower, but require a dedicated crew and may only be used once each before recharging. The strike of a thunderbolt thrower creates a deafening boom of thunder at the point of impact. All characters on a ship struck by a thunderbolt thrower suffer a Harried modifier until the end of the ship combat turn (additional strikes do not cause Overwhelmed effects). Thunderbolt throwers are not mounted to the ship’s deck and require at least 3 crew for most namegivers to operate (at least 2 trolls or 1 obsidiman), as the recoil can knock a single troll down or across the deck. As they are not mounted to the ship, they have a 360 degree firing arc. Thunderbolt throwers can only be recharged by an Elementalist, Sky Raider, or Weaponsmith while the airship flies through a storm. The character recharging the thunderbolt throwers makes a Recharge test by rolling their Thread Weaving step plus the ship’s Maneuverability step versus the current Hazard Level. Success recharges two thunderbolt throwers, plus one for each additional success. On a Rule of One result the character has been struck by lightning (Air-Electric damage), roll the Hazard Level as a Damage test and apply Physical Armor.

Or, and I ran a preview of this in the forum this week, my new ship-class weapon, the Arcane Focus. I could see some of the snake Wizards return with such crazy firepower.

QuoteArcane Focus
Crew: 2 (see text)
Damage step: Spell Effect Test + Adept’s Circle
Short Range: Spell Range x2
Long Range: N/A
Base Cost: 5,000 Silver
Weight: 150 pounds / 2 per duari
Created by a mysterious windling Wizard in the days after the fall of Sky Point and Vivane, the arcane focus is a rare ship weapon. The major powers of Barsaive (such as Throal, Blood Wood, the major cities, or the t’skrang houses) only possess a handful of these devices each. An arcane focus resembles the tip of a thunderbolt thrower mounted on a gear driven ballista-swivel, with a “sighting tube” above the mass of crystal and orichalcum wire. Runic enchantments are inscribed on every wooden surface and the device hums audibly when a spellcasting adept approaches it. The unstable mana means these weapons may not be placed near each other and each arcane focus counts as a battery when activating ship-weapon units. The arcane focus requires one assistant, and allows the spellcaster operating it to attune one of their matrix talents to the device by making a Patterncraft test against the spell in the matrix’s reattunement difficulty. The attunement will last a number of minutes equal to the number of successes scored. Once attuned, the device may be used once per minute (10 combat rounds) to aid the caster in creating the astral arc to the target sighted. The chosen spell may then be cast at a single target (including ships or units) up to double the normal spell range with a bonus to the Spellcasting test equal to the adept’s Circle. When activated the spellcaster may take up to 4 rounds worth of actions to weave all required threads before spellcasting, and may add a bonus to the Effect test equal to their Circle. These rules replace the normal bonuses Adepts receive in mass combat. Called shots may not be made with an arcane focus.

A light escort wagon:
[ATTACH=CONFIG]1031[/ATTACH]

Weapons.  

Spike the wheels some how.  Anchors.  

Fire ball into the rigging.  

So wizards.  Every wind wagon needs a spell chucker.

One other problem with ramming: rowers can easily reverse direction but you can't easily reverse directions with a sail.

A battle wagon:
[ATTACH=CONFIG]1033[/ATTACH]

Are the Agarthainians the only people riding these wagons?  If so you don't really need all these ship to ship combat designs.  They wouldn't have them.  And If anyone ordered a wagon clearly designed to for war or piracy there might be some questions.

What beasts are out on those salt flats?  Bandits? Nomads?

Quote from: Headless;966668Are the Agarthainians the only people riding these wagons?  If so you don't really need all these ship to ship combat designs.  They wouldn't have them.  And If anyone ordered a wagon clearly designed to for war or piracy there might be some questions.

What beasts are out on those salt flats?  Bandits? Nomads?

The end points of their trade routes are well within the range of horse nomads, so the war wagons are mostly a defense against them. But there are also other Agarthanians. The factions are mostly separated in their own fortresses or fortress systems, and while there is no open civil war yet, it can't hurt to strap a catapult on a war wagon just in case. Battles between war wagons haven't occurred, so no one knows how effective those are. And I guess those wagons aren't very widespread, either.

Does anyone has formulas to get from sail geometry, wind speed/direction and vehicle speed/direction to wind force?

Its a low magic setting I take it?  

My sorc would want to jump on that fliating disk and go water skiing behind.  :cool:

Quote from: Headless;966688Its a low magic setting I take it?

No or very low magic is my plan, yes. But that shouldn't influence your sorcerer in any way. :)

Ohh?

Low Magic with possible PCs fireball chuckers?  To my mind one fireball into the rigging and the sails go up in flames.  The enemy wagon rolls to a stop and the PC wagon continues on trusting the sun an wind to finnishing killing the enemies.  Fatalities over 90% from sun stroke and dehydration.  

That would end an exciting encounter in one spell.  Instead of enabling exciting ship to ship combat.

No, you can't play your sorcerer in my scenario. ;)

Quote from: Pyromancer;966678Does anyone has formulas to get from sail geometry, wind speed/direction and vehicle speed/direction to wind force?

Get the difference between the wind vector and the vehicle vector to get the relative vector of the wind on the vehicle.
Compare the angle of that vector to the angle of the sails and use trigonometry to get the component of force in the direction that the vehicle is constrained to move by the wheels.
Take the density of air (varies slightly by altitude and humidity), multiply by the air speed component in the direction of the wheels, to get the force.
Divide by vehicle mass.

There would be the same sort of effect from the hull's sides that face the wind.

Also calculate force of friction from the wheel system reducing momentum.

You might be able to get some actual formulae if you ask nicely on either math.stackexchange or engineering.stackexchange.

Everything else is no problem, but this:

Quote from: Skarg;966718Compare the angle of that vector to the angle of the sails and use trigonometry to get the component of force in the direction that the vehicle is constrained to move by the wheels.

In reality, (as far as I know), it isn't as simple as that, but there is some complicated aerodynamics happening at that step. That's the reason why the sail geometry is important, and not only the sail area and angle. But I'm no sailor myself, and live far from the shore...

Something to consider.

How frequent and reliable are the wind currents? Are they seasonal? How strong can and do they get?

From this you can get things like weather diviners who can more or less accurately predict the currents on a given day.

Ohh wind deviners.  I like that. To me thats an interesting Guild in and increasingly detailed world.

Sail formulas just sounds tedious.  If you want to go that route look for a book on elementry sail navigation.

Me I would just read books on Nautical miltary fiction.  Master and Comander might be a good one.  There is a tedious David Webber serries that starts with Off Armageddon Reef, a super advanced space robot from the past is theaching them to sail better in a couple of those books.

The Brothergood of Wind Deviners.

The Honorable Order of Wheel Wrights.

The Ancient and Honourable Porters Guild

The math can and should be front-loaded, unless you're making a computer simulation.

You can use understanding of what's going on in the physics and its math, combined with real-world examples, and extrapolate and estimate to get typical stats based on size, weight, and rigging, and make tables for them that show, for a variety of typical designs, what speed and/or acceleration to expect for each angle of wind direction relative to the wheels. See for example Avalon Hill's Wooden Ships & Iron Men, where every ship has a maneuver class that tells you what table to use, and you look up the current relative wind direction there to find the max speed, modified for rigging settings and damage.

I wouldn't even go so far. I just want to check if the designs are viable at all, and then estimate the rest.

Apparently they were used a fair amount in China and later theres this from the 1600s

(https://upload.wikimedia.org/wikipedia/commons/thumb/9/96/Simon_Stevins_zeilwagen_voor_Prins_Maurits_1649.jpg/1024px-Simon_Stevins_zeilwagen_voor_Prins_Maurits_1649.jpg)

At wind strength 4 (moderate breeze), the cargo wagon goes ~20 km/h, even perpendicular to the wind, and can go slightly upwind wind, too - if empty.
Fully loaded, top speed drops to ~15 km/h, but the wind has to blow diagonally from the back for that. Perpendicular to the wind, speed is around 7 km/h, and going upwind is impossible.

Cool thread!

Was going to make a similar thread but never got around to it. So here seems as good a place as any.

The velocipede struck me as the sort of riding vehicle you might see in some fantasy settings.

(http://www.photo-museum.org/wp-content/uploads/2015/02/velocipede-niepce-invention.jpg)

Its essentially a foot-powered bike. Made of wood and the sort of thing dwarves or elves might make. Especially dwarves.

And then theres this. Just because its so fantastical that it should be in a fantasy setting.

(https://3.bp.blogspot.com/-FkH3of_Suzo/VRdVNFS6GvI/AAAAAAAABr4/auXwlhf7Y2s/s1600/Scientific%2BAmerican%2Bvolume%2B20%2BMarch%2B6%2B1869%2B-%2BUnicycle%2Bor%2BFlying%2BYankee%2BVelocipede.jpg)

My PCs were trying to haul their loot, supplies and wounded in a wagon. They were attacked on the road near a frozen lake and their mules were killed. So they rigged up the wagon like a big sled, built sails* and crossed the lake to safety -launching a couple of fireballs at the ice under the giants and winter wolves chasing them. I gave out big XP bonuses for taking the howling winds I mentioned in passing just to describe the wintry weather and surprising me with their ingenuity.

* An extra bonus for the PC who insisted on taking the tapestries even though they were bulky and a pain in the ass to carry, and everyone else wanted to leave them behind.

Sail wagons are cool as fuck and I only wish I'd thought of them way back when.

I really hope the valuable resource they are all delivering at high speeds, and even warranting piracy and boarding actions, is produce or chilled confections. Somehow Mad Max over lettuce and ice cream seems like a thing that needs to happen.
:cool:

Shipping ice was one adventure one of my characters ended up on once. In that case it was a sand-sled style sail ship rather than a wagon. I believe the DM was inspired by the ones from Martian Chronicles. The ice was mined through a gate to the plane of ice and shipped fast to the capitol and some other major cities.

What was it for? I never found out.

Smoothies and ice-cream man. http://www.amusingplanet.com/2013/01/ancient-ice-houses-of-iran.html

"flying yankee velocipede".  Man oh man.

Quote from: RPGPundit;969496"flying yankee velocipede".  Man oh man.

I guess "Hand Powered Monowheel" was too mundane for the tabloids.

You may find this useful: http://physicsbuzz.physicscentral.com/2015/05/the-physics-of-sailing-how-does.html

TL;DR:  Much of what makes sailing work is unique to the naval medium (water drag, shape of the hull, the keel).  You can't tack in a landship, for instance.  This makes using them for regular trade routes fairly pointless, as you can pretty much only run before a following wind.

Personally I wouldn't bother with that level of physics detail, though.  Once you start looking into vector mechanics and sail positions, it gets harder and harder to ignore the fact that the whole notion is impractical.

One option is catamaran style hulls with knife keels on a very fine silt sea or something.

That is what I thought as well (having experience sailing). This outfit claims their sail-wagons _can_ tack into the wind: https://www.detourvegas.com/pages/safe-use-of-toys

I wonder if it is the 3 wheel design, the sail-rig, or something else....

Very small, very lightweight hull and the center of gravity is low enough that the weight of the person in the skiff (this isn't a wagon by any stretch of the imagination) creates enough drag to mimic the effect of the keel in a boat.  Plus the outrigger style wheels keep it from flipping when it tacks.

I should probably clarify: "you can't tack in a landship" because all the designs that seem to pop up have the center of gravity very high off the ground with minimal drag from the wheel contact.  Add in outriggers and you're probably all right, but tipping is going to be a real hazard.

I suppose if you just wanted something that looked plausible enough you could scale up the three-wheeled skiff design and hand-wave any issues with wind force/weight ratios.

Interesting, thanks for that take on the design aspects.


Oh, if anyone is interested in how to use the ship stats that I put up for the Sailing Wagon, I have begun to preview my new rules for the Earthdawn 4E Ship & Mass Combat system over in the Design, Development, & Gameplay forum. Link: http://www.therpgsite.com/showthread.php?37161-Earthdawn-4E-Ship-and-Mass-Combat

I think these types of vehicles would fit in quite well in certain "Wasteland-y" parts of the Earthdawn setting.

Quote from: daniel_ream;969673You may find this useful: http://physicsbuzz.physicscentral.com/2015/05/the-physics-of-sailing-how-does.html

TL;DR:  Much of what makes sailing work is unique to the naval medium (water drag, shape of the hull, the keel).  You can't tack in a landship, for instance.  This makes using them for regular trade routes fairly pointless, as you can pretty much only run before a following wind.

Personally I wouldn't bother with that level of physics detail, though.  Once you start looking into vector mechanics and sail positions, it gets harder and harder to ignore the fact that the whole notion is impractical.

One option is catamaran style hulls with knife keels on a very fine silt sea or something.

What about if I wanted to make this all Mad Max 'n shit with technobabble? Could I feasible pass "solar-powered battery-ran gyroscopic keels?" It'd give the resistance needed; will it need a 3-axis chassis (like some atlas globes) with a lockable mechanism?

Given fresh salads and ice cream, and Mad Max's Aunty Entity (Tina Turner) and Imperator Furiosa (Charlize Theron), it sounds like a marriage made in gonzo, high concept heaven. "I need the Pinkberry fro-yo, now! And bring back endives, we're hosting a dinner party tomorrow night!" "... many pirates shall die on the salt pan today, my love."

Quote from: daniel_ream;969673You may find this useful: http://physicsbuzz.physicscentral.com/2015/05/the-physics-of-sailing-how-does.html

TL;DR:  Much of what makes sailing work is unique to the naval medium (water drag, shape of the hull, the keel).  You can't tack in a landship, for instance.

Of course you can tack in a landship. You can do it even better than in a watership.

QuotePersonally I wouldn't bother with that level of physics detail, though.  Once you start looking into vector mechanics and sail positions, it gets harder and harder to ignore the fact that the whole notion is impractical.

It isn't impractical at all.

I have simulated a few designs (using NASA software to simulate the airfoil effects of the sail :cool: ), and they work - as should be expected, since they work in real life, too.

I will put together a document with achievable top speeds, depending on wind speed and direction, for those who are interested.

Quote from: Pyromancer;970964I have simulated a few designs (using NASA software to simulate the airfoil effects of the sail :cool: ), and they work - as should be expected, since they work in real life, too.

Does your NASA software simulate tipping over because you have a giant airfoil on top of a narrow body with the center of gravity three feet off the ground?

Quote from: daniel_ream;971072Does your NASA software simulate tipping over because you have a giant airfoil on top of a narrow body with the center of gravity three feet off the ground?

No. The tipping over part is done by my own software - this isn't rocket science, exactly.
Regarding the "narrow body": Look again at my first sketch. The wagon has an axle track of 7 m (23 feet for you Americans) for exactly this reason. The danger of tipping over is still present, but this is what skill rolls are for.

I find it irritating that you insist that sail wagons are infeasible when they existed and still exist in reality. The problem with sail wagons isn't that they don't work, it's that they need a special kind of landscape to make any sense. A landscape like this:
(https://upload.wikimedia.org/wikipedia/commons/thumb/9/90/OmnogoviLandscape.jpg/800px-OmnogoviLandscape.jpg)

That is the ship of the desert, not a sail wagon, they spit.

Quote from: Pyromancer;971106I find it irritating that you insist that sail wagons are infeasible when they existed and still exist in reality.

"They exist" and "are infeasible" aren't mutually exclusive.

Since much of tacking before the wind relies on the wind not simply blowing the ship sideways because the drag force of the keel pushes against the water, does your much-vaunted software take into account how high the coefficient of friction between the wheel and the very tiny contact area between them and the ground needs to be to keep that from happening?  I'm assuming the wheels have wooden or iron rims and not, say, vulcanized rubber.

It's from an empire founded by snakemen, I think we left behind Feasible and raced over into Cool a while back.

Quote from: daniel_ream;971318"They exist" and "are infeasible" aren't mutually exclusive.

Since much of tacking before the wind relies on the wind not simply blowing the ship sideways because the drag force of the keel pushes against the water, does your much-vaunted software take into account how high the coefficient of friction between the wheel and the very tiny contact area between them and the ground needs to be to keep that from happening?  I'm assuming the wheels have wooden or iron rims and not, say, vulcanized rubber.

I use iron rims in my model. It turns out the wagen tips over way before the wheels starts skidding sideways. Again, this part isn't rocket science. You can calculate that on the back of a napkin, and you should do it yourself, if you are still skeptical. Since you know complicated words like "coefficient", you must be smart, so I'm sure you are able to do so.

Long story short, no gyroscopes needed, just wider axles on the catamaran? Also have the flat salt pan roughly as big as Kansas. Gotcha! :cool:

Quote from: Opaopajr;971363Long story short, no gyroscopes needed, just wider axles on the catamaran? Also have the flat salt pan roughly as big as Kansas. Gotcha! :cool:

Or bigger. Like the Sahara desert or Siberia sized bigger. And dotted with isolated outcroppings of rock carved into citadels and natural springs that well up from the rock. So there is someplace to go in your sail wagon.

Quote from: Bren;971365And dotted with isolated outcroppings of rock carved into citadels and natural springs that well up from the rock. So there is someplace to go in your sail wagon.

That's exactly the idea I had:

[ATTACH=CONFIG]1097[/ATTACH]

That's an Agarthanian fortress, approximately.

Quote from: Pyromancer;971368That's exactly the idea I had

The mesa looks good. Obviously the foreground should be much more level so the wagons can sail along...though perhaps there are 'shoals' around some of the 'islands.'

Apologies if you already mentioned that rock outcroppings and if it seemed like I was nabbing your idea. Some sort of isolated towns extend the sea of sand metaphor as these are the island analogs for this place. And obviously some sort of settled lifestyle is probably necessary to support the existence of the sail wagons.

Quote from: Opaopajr;971363Long story short, no gyroscopes needed, just wider axles on the catamaran?

If you make the axle track wider, you can tolerate stronger sideway forces, and that means you can a) go faster, and b) sail closer to the wind. With a narrow axle track, you can only sail before the wind.

For similar reasons - the longer lever arm -  a modern "high rig" / "bermuda rig" (as shown in my first sketches here) isn't as suitable for sailing wagons as the more old fashioned, and lower, latin rig. So the more appropriate for the timeframe and more stylish design actually makes more sense from an engineering standpoint, too.

Edit: Spoilers might also help, but I'll have to crunch the numbers to see if the effect is worth the effort.

And I know, all of this doesn't matter in actual play. But it satisfies me if I know that it isn't all bullshit and "magic", but has a basis in reality.

Ok, spoilers ("wings") can add a few km/h at high speeds that are unsafe anyways, so aren't worth it.

OK, what sort of average speed can I expect from this thing, given the utility of cargo transport? I'm sure any peak 100 mph speeds drop considerably once we get a few bushels of lettuce on there. Basically, at what sort of speed range should I assume for my Mad Max boarding battles for salads and chilled confectionary?

40+ for grocer ships?
80+ for gelato ships?

Quote from: Opaopajr;971635OK, what sort of average speed can I expect from this thing, given the utility of cargo transport? I'm sure any peak 100 mph speeds drop considerably once we get a few bushels of lettuce on there. Basically, at what sort of speed range should I assume for my Mad Max boarding battles for salads and chilled confectionary?

40+ for grocer ships?
80+ for gelato ships?

I will compile a list soon, since this strongly depends on wind force and direction. But for optimal conditions, those speeds are possible.
In my current writeup, I require additional skill rolls for speeds over 35 mph and rolls on "structural integrity" of the wagon for speeds over 45 mph.

I have have similar rules for some of the smaller airships and sailing boats in my Earthdawn rules. My Speed Step table maxes out just above 55 mph, tho. I know modern ships can top that, but most historical ones of the types we are emulating (drakkar, karver, Mediterranean galley, etc) could not. Interestingly (this is the part where FASA mashed Elric up with Atlantis), the Theran Empire's flying castles have the highest normal running speed. Of course, they do use slave power (like, mana ripped from the slaves all Dark Crystal style)...

Anyway. Most smaller ships in my system have to make a Hazard check at wind speeds above a certain mark, and the smallest simply cannot be operated in certain higher wind speeds. Wind speed also adds modifiers to the local Hazard level. So, a Badlands like pictured would have a High Hazard Level (9), with a +1 for winds under 25mph, +2 for above 25mph, and +3 for severe storms or winds above 30 mph. Navigation tests at the start of each turn can apply some temporary Hazard Level bonuses reducing the current rating. Then, roll the rating as a Step vs 13.

I really like how this thread has gone. I'll have to think about where these land ships fit in my home game.

How common are these landships? The more common they are the more the setting will suggest that there must be fairly regular wind currents from point A to point B and then back again. Possibly in a large circular route such that from orbit it light look like the area has a cloud spot or ring perpetually circling that region.

Or something like the tide that regularly sweeps in and then out.

Quote from: Bren;971377The mesa looks good. Obviously the foreground should be much more level so the wagons can sail along...though perhaps there are 'shoals' around some of the 'islands.'

Apologies if you already mentioned that rock outcroppings and if it seemed like I was nabbing your idea. Some sort of isolated towns extend the sea of sand metaphor as these are the island analogs for this place. And obviously some sort of settled lifestyle is probably necessary to support the existence of the sail wagons.

There are a few cases of sail wagons being used on the Great Plains,including at least one that traveled over 600 miles from Kansas City to Denver (over 600 miles) in 30 days (https://www.kshs.org/kansapedia/wind-wagons/12239). Which is quite remarkable considering that by going from east to west, they were going against the prevailing winds. It's also remarkable because it's true that most of Kansas and a good chunk of Colorado are prairie, there are hills, woods and other speed-bumps: It's NOT like Death Valley and other completely flat lands.

Not to mention 4 river crossings and climbing over 4200 feet of elevation.

Quote from: Elfdart;972062There are a few cases of sail wagons being used on the Great Plains

From the same article:

QuoteThe few wind wagons that were built undoubtedly traveled further in the press than they did on the prairie

Taking the reports of Midwestern newspapers at face value in the mid-nineteenth century is like asking Nicodemus Legend to defend your town from bandits.

As I said before, "possible" and "feasible" are not the same thing.

Also buried in that article:

QuoteA crank and band wheels allow it to be propelled by hand when wind and tide are against them.

Quote from: daniel_ream;972166Also buried in that article:

QuoteA crank and band wheels allow it to be propelled by hand when wind and tide are against them.

I read that. My thought was that a crank for motive power must have worked real well. :rolleyes:

Quote from: daniel_ream;972166From the same article:



Taking the reports of Midwestern newspapers at face value in the mid-nineteenth century is like asking Nicodemus Legend to defend your town from bandits.

As I said before, "possible" and "feasible" are not the same thing.

Also buried in that article:

If it's good enough for the papers 150 years ago, it's good enough for a FANTASY GAME.

Quote from: Kyle Aaron;971350It's from an empire founded by snakemen, I think we left behind Feasible and raced over into Cool a while back.

Shhhhh! Someone might post several times that snakemen aren't "feasible" either.

OK, so let's say I have four snakemen, averaging 140 lbs, on a catamaran 80 miles away, going SE perpendicular to the seasonal NorEaster, trying to intercept a noon Gelato shipment riding the headwinds with a skeleton crew to Nuevo Laredo 200 miles away, how early should these snakemen sun themselves to warm up if the gelato has pralines, which ups its resale tremendously?
:confused:
Thanks in advance! :cool:

They need to be rolling before they wyverns take to the skies.  They won't like that cuase its a bit early for the cold bloods.  But by noon, if they send up the falcons they should spot their quarry.

Patience, patience! I'm working on a document that will help you to answer all these questions, but I'm doing this in my free time. :cool:

Quote from: Opaopajr;972414OK, so let's say I have four snakemen, averaging 140 lbs, on a catamaran 80 miles away, going SE perpendicular to the seasonal NorEaster, trying to intercept a noon Gelato shipment riding the headwinds with a skeleton crew to Nuevo Laredo 200 miles away, how early should these snakemen sun themselves to warm up if the gelato has pralines, which ups its resale tremendously?
:confused:
Thanks in advance! :cool:

I think it all depends on if you grip the coconut by the husk.

Regardless of realism, I love the idea of desert cultures using huge ships that glide along the sands via wind power.

Me too! I've collected some concept art (much of it is from Monster Hunter 4):

Images:
https://vignette4.wikia.nocookie.net/deathbattlefanon/images/8/8a/Dah%27ren.gif/revision/latest?cb=20150908222929
https://s-media-cache-ak0.pinimg.com/736x/d9/40/3a/d9403a71deac2b1e5de802f5e36890e3.jpg
http://www.allamassor.se/uploadBilder/news/bb.aspx.jpg
http://33.media.tumblr.com/c361e0c66f97f64709f69d93a713d625/tumblr_inline_nkweubEO9d1toqqyz.png
https://vignette2.wikia.nocookie.net/monsterhunter/images/f/fc/LocLacCity01.jpg/revision/latest?cb=20100311201126
http://www.n-sider.com/images/inline_images/inline-4-4028-3.jpg
http://68.media.tumblr.com/9a2627364d76525b1a28ab42bc24472f/tumblr_mne0ljGmX51ssr51lo1_1280.jpg
https://s-media-cache-ak0.pinimg.com/originals/6d/dd/dc/6ddddc7cb0822ae4238d718f43eaddea.jpg

Threads:
http://theminiaturespage.com/boards/msg.mv?id=246646

[/SIZE]

It's done:
http://www.drivethrurpg.com/product/216526/


Deep in the Gobi desert, there lies the Kingdom Agarthi. Once a powerful empire ruled by ruthless snakemen and their human underlings, the snakemen are now a distant memory, and the humans mostly feud and plot among themselves. Only now and then, one or another of the factions sends out an expedition to trade with the humans out there, the Mongol steppe nomads to the North, or Chinese villagers to the East. For gold and precious stones, they barter slaves, food, and news from the outer world. This is the only time Agarthanian sail wagons are ever seen outside the desert...

Sail wagons are an exotic means of transportation, but they are ideally suited for dried out salt lakes or flat desert plains. In reality, the ancient Chinese used them, and they made a very minor comeback in modern times. But the idea is sound and workable with medieval or even ancient technology.

This document contains three different sail wagon designs that can be included into your campaign world:
1) A cargo sail wagon – used to transport goods and optimized to run with a small crew
2) A scout sail wagon – fast and optimized to tack. Same stats can be used for private pleasure crafts
3) A battle sail wagon – full of soldiers, mostly used for escort duty or punitive raids

Each wagon comes with schematics and tables for top speed, dependent on wind speed and wind direction. Wagon speed is given in meters per second, kilometers per hour, miles per hour, and feet per game round (10 seconds).

Sail wagons are suitable for medieval, fantasy and post-apocalyptic game worlds. This supplement gives you all you need to incorporate it into the game system of your choice.
http://www.drivethrurpg.com/product/216526/

And for those who are interested in the physical backgrounds I used to calculate the speed values I give:
http://www.drivethrurpg.com/product/216527/

Congrats.

Good job!