In a medieval society, an ethnic group lives most of their lives aboard airships. These airships are rudimentary, perhaps holding only enough room for a single family. They consist of slender wooden hulls, large bags of hydrogen for lift, and leather wings for shifting trajectory. Due to the lack of propellers, they generally follow prevailing winds. However, a significant issue with this lifestyle presents itself: food.

What organisms and techniques could these people use to create a nomadic society amongst their airships?

Please keep the technology around medieval levels.

• I'm not sure pastoralist is the right word for this, as that implies actually tending flocks of pasturing animals. However, plenty of nomads follow herds, etc. You could definitely have a migrant people in this kind of situation. Nov 15 '21 at 21:29
• @coppereyecat Yeah, nomadism is the word he's looking for, of which pastoralism is one possibility. Nov 15 '21 at 21:31
• Another vote for trading here. Just because you live a nomadic life in an airship doesn't mean you can't trade for food. In fact, the single family in a small vessel made me think immediately of the old narrow boat families. They provided transport for goods and bought food. If your airships could drift on predicable trade winds, maybe up and down a series of narratively helpful terrain features, they could fill this niche. Nov 16 '21 at 8:09
• You underestimate vastly how hard it is to contain hydrogen. It's definitely not "around medieval levels" Nov 16 '21 at 21:00
• How are they producing the hydrogen? Nov 17 '21 at 6:51

# Hunting birds bring nearby food sources back to the airships

• Falcons for migrating birds
• Cormorants for fish

Falconry is a Eurasian hunting method dating from the 13th Century BCE and well into the Late Medieval Period c. 1500 CE. The falcons fly out to catch small game and bring it back to the handler.

In your scenario, each airship has one or more of these birds, which are trained to retrieve migrating birds as they pass nearby and bring them to the airships. I believe a reasonable active range is at least 0.6 mile / 1 km away from a handler in calm conditions (having observed this myself at falconry displays).

Consider the traditional Chinese cormorant fishing rafts, where the fisher and the birds have a symbiotic relationship; the cormorant eats a portion of the total catch as "reward" for helping the fisher. In fact if you add buoyancy controls to your airships, then they could even descend to near sea-level and allow actual cormorants to fish for them.

• Issue: birds are smarter than fish. Even fish can learn to avoid nets; birds will definitely learn to avoid the nomadic airships miles away. Nov 16 '21 at 18:40
• That's a great picture, but you should credit where you got it. Nov 16 '21 at 19:10
• That's absolutely right @chrylis , thank you! I've added it below the image. Nov 17 '21 at 19:34
• @Neinstein that might be a valid point. I guess it could be alleviated by having a lead airship which only has seeds or fish out to attract birds to it, and the second airship further back has the hunting birds. Prey birds may still go for the "safe, easy" food source on the lead ship despite the danger of the second one. Nov 17 '21 at 19:48

However, a significant issue with this lifestyle presents itself: food.

I like airships as much as the next person[1], but all the numbers involved in them are against your medieval society. Especially if "pastoral" and "nomadic" implies "poor", as shepherds traditionally are. Estimate a person at 150lbs, then a family of four are 600lbs. Add all the trappings of airship and life (gondola, gas bags, ropes, clothes, tools, water, some leeway, etc) and call it a minimum of 1,000lbs that needs to be lifted (I suspect I am erring on the low side). The Hindenburg could lift ~500,000 lbs (including its own mass). It took 250,000 dead cow intestines to make the lift bags for it.

By my conveniently estimated numbers your airships need to be at least 1/500th of a Hindenburg. Balloons ~6.5 meters long, 8 meters wide, 8 meters high, filled with 435 cubic meters of Hydrogen - 40 concrete mixer trucks sized. And will take 500 dead cows.

Compare the GoodYear Blimp which has 10-20x more Helium lift gas:

and even that would confine the family to live in something like this size:

Compare also the Airship America built in 1905, his company had an investment of \$75,000 which is over \$2,000,000 in today's money accounting for inflation. Then he started to fundraise for the airship.

This airship is also bigger, but the cost is surely non-trivial.

One idea you could take from The America is that wonderful equilibrator hanging down into the water. "Wellman and Vaniman’s idea was that as the airship lost lift at night, and settled toward the surface, the equilibrator would descend into the ocean; for every four feet the airship descended one gasoline tank would be lowered into the sea, reducing the airship’s load by 100 pounds and ultimately checking the ship’s descent. When the airship gained lift during the warmth of the day and began to rise, it would lift a number of the gasoline tanks into the air, increasing the ship’s load and thus checking its ascent.".

Make them water bottles instead of fuel tanks, and you have a low-tech way to control the airship's height while also having a way to trawl for fish or a ladder up/down to ground level. If they drifted slowly over land, and this dragged on the land, people could go down to hunt and socialise and come back up. If they could be tied to several buffalo harnesses, those could drag the airships along with the herd and keep all the tribe together.

However, a significant issue with this lifestyle presents itself: food.

Technology, boredom, exercise, dating and partying.

It might matter - where do they get their Hydrogen from? (It wasn't even discovered for 200+ years after medieval times on our Earth). Are they going to make it with chemistry, trade for it, or obtain it from a natural source? Any one of those could be a reason to land.

The lift bags? They might have to be partly ground-based to kill so many cows and process their intestines. That would give them plenty of time to preserve the meat for food. And as airship lift power goes up with gas volume, and volume goes up much faster than length and width, so adding a bit more size and a lot more volume would make it plausible to lift provisions long term.

The site linked below[2] estimates that stockpiling enough food for a person for a year weighs about 500lbs. It could be arranged that if they can make a 1,000lb-lifter, they can make a 2,000lb-lifter and bring months of food with them.

I think you could adjust these things with a bit of story telling license to make them able to preserve months of food at a time. They fly over the Great Plains, keep in contact with each other with long range signalling, every 6/9/12 months they all land together, hang out for a while killing and preserving salted buffalo and intestines, making repairs, trading, partying, then leave with enough food for another long time.

They can collect seeds, tempt birds in and catch them.

You haven't said why they have this lifestyle, in story terms. It must give them some benefit for the huge cost, effort, and risk involved. Is there something high up of great value? Do they make and sell maps? Capture animals which are naturally Hydrogen filled and flying high? Act as mercenary bomb-droppers for warring factions? Something like that could give them value to trade to get food from others.

[1] or perhaps a little more; did you know the Graf Zeppelin was the first vehicle to fly a million miles? That it had asbestos roofing over the smoking room to protect the lift bags? That it was the first vehicle to fly to the North Pole? That it was a post sorting office and funded mostly by stamp collectors getting mail sent through it? That it used to brush against clouds to collect water to replenish the ballast tanks? That there were people in each of the engine compartments who had to manually adjust the speed in response to the Captain's orders? That Steinway made a lightweight Aluminium Grand Piano for the Zeppelin company? That the Hindenburg used sonar pings down to the ground to measure altitude? That they invented fuel the same density as air, so as they burned fuel and emptied the tanks, the ship didn't get lighter? That they banned sausage making in Germany, Austria, Poland because they needed so many intestines for Zeppelin lift bags?

• With regard to that tiny cabin, I can't help but draw comparisons with the traditional cart/wagons of Gypsies. Which tend to be very compact indeed. I suppose the difference is that generally the cart/wagons tend to stop somewhere for the night and unpack, rather than being bedroom, bathroom, kitchen, storage and more for a whole family 100% of the time for days on end. Nov 16 '21 at 15:15
• @Ruadhan and be able to gather firewood instead of carrying it with you, walk alongside the horses, cook outside, yeah. Another interesting comparison is Joshua Slocum's boat The Spray in which he made the first solo sail trip around the world in 1895. That's a 12 meter long boat with one person living in it for a few weeks at a time before stopping to gather water and firewood. He had to bathe in the dinghy he kept on the outside, it had no toilet, etc. Spray was 12 meters long and weighed 18,000lbs. I'm assuming 6.5m long, 1,000lbs and 4 people. Wood is heavy. Nov 16 '21 at 16:44
• Not nomads then, vikings. Nov 17 '21 at 8:38
• In line with this answer: Square-Cube Law. It'd be more practical to have communal airships that several families use rather than an individual aircraft for each family, as you'll get far more "lifting power" the bigger you make the airship. Smaller aircraft that rely on buoyancy are just too difficult compared to much larger aircraft with more people.
– Iter
Nov 18 '21 at 1:26

Depending on the specific region of the aetherial seas you're looking at, Skyherd folk might follow any one of several great flockbeasts of the sky!

In the warm lands of Irinsurea, skyherd folks follow after the air buffalo as they wander from current to current, wallowing in the warmdraughts of the midverticals. These creatures are a wonder to behold! Large puffy starfish shaped behemoths, their bodies are little larger than an ordinary water buffalo calf but it's the great hydrosacks that make them so impressive. Land dwellers fear the coming of the air buffalo herds, taking their sky darkening movements are ill omens of doom. And they're right to dread! Although the only serious threat the air buffalo ever really pose is a near constant rain of piss and a drizzle of watery poo. It is for this reason that the Curellians invented three kinds of brollies: the parasolelh, a nice, light & gaily coloured thing to provide a little shade on hot sunny days; the paraplueya, a sturdier device to ward off showers of rain; and the paramerda, to shield from the seasonal effluvium.

In the drier climes of Phazzanea, the Windwardens hunt the riparhinoceros. This is a deadly beast, and no lazy floater! Bull riparrhinoceroi gallantly and bravely defend the rivers of air above the wafting grasslands below. Their long pointed nose horns seem like the sharp prows of a war galley, though in reality, they are more for display than for actual combat! Though occasionally a particularly rough display of prowess will cause the rupture of another beast's hydrosack!

• nice etymologies for your umbrellas Nov 16 '21 at 20:24
• @ermatveit --- Well, two out of three are just ordinary Occitan words; the third one is an extrapolation! Nov 16 '21 at 22:04

# Aerial Trawling!

Your pastoral airships often pass over large bodies of water - many wind patters hug the coasts of continents. When they're feeling hungry, drop the nets! Trawling nets can catch huge amounts of fish and other sea creatures, and fish (unlike migratory animals) are almost always a reliable source of food year-round near the coastlines.

Your airships gain a special advantage when choosing fish rich areas, the trawling will slow them down significantly, allowing them to linger over these areas for an extended period of time!

(Assuming your okay with altering the world slightly) add some animals in the surrounding area to eat.

Like various birds(or just increase their numbers in the area to make it work).

Or change a few migrational behaviors and have those birds ALSO follow the wind, same as your airships (idk if they already do, some birds, I assume more often no).

Also, make sure these people are okay with eating flying bugs, cause thats the most reliable source of food I can think of up there.

Hope this helps

They can follow/search for migrating birds and use them as food supply. Ducks and geese, for example, are already used by humans as food. They could stock on them when they get the chance, so to build storage for meager times.

Together with that, when the winds bring them above the sea, they could throw nets or lines and fish.

Last but not least, they could lower down a single hunter with an harpoon like weapon attached to a rope, who could use it to hunt large game or fish, and then recover it by pulling the rope. This would work on open sea or prairie-like environments.

• To play on your idea of lowering a hunter: For a neat steampunk vibe, they could have clockwork bombsights. They precision-drop a harpoon on some unsuspecting animal and then reel it back in to consume at leisure. May as well use their altitude for power! Nov 15 '21 at 20:10

And they could live as Kings.

Trade was important in the Middle ages (specially in the second half). But it was hard, slow, and dangerous. Roads were poor, mountains, rivers, marshes, etc, were huge obstacles, make trade hard and dangerous. The Middle ages lacked good infrastructure. Being able to move through air means many natural obstacles aren't obstacles any more (although crossing seas may still be dangerous, and crossing oceans is probably out of the question). Merchants would pay a premium to be able to trade more quickly. (Not to mention an airship could avoid crossing through towns and cities which levied tolls, and they be harder to rob).

## Warfare

An alternative way to live like Kings.

They could act as mercenaries. A siege of a town or castle will have a very different outcome if the town or castle could be bombed from the sky. Even if airships would only be used for reconnaissance, the side which has access to airships has a major benefit.

• Warfare is a good point: especially in the Medieval Period, mercenary bands formed around the availability of specific advanced technologies like early arbalests, firearms, etc; so, if some group had access to airships, they would be prime candidates for the mercenary lifestyle... however, I have to disagree with trade. Airships are very expensive to make and operate compared to boats or wagons for thier carry capacity. They would have to stick to very high profit, low weight commodities along very specific trade routes to have any hope of making a profit at all. Nov 16 '21 at 20:17

## Nomads Can Not Survive This Way

The biggest problem with this scenario is that the nomads have no control over where they go. They could have a perfectly good method for feeding themselves in their preferred biome, but then get blown into a desert or mountain range or tundra and then all starve to death because their method of feeding themselves become undoable in the new biome. Remember, the whole point of being a nomad is that you get to choose where to go to find more resources when you need them. This makes your nomads better off just footing it wherever they want to go than being dragged randomly where they may or may not want to be.

On top of this, airships are a huge investment in terms of both upfront cost, and maintenance; so, you need to justify that cost with some added benefit. While a family could perhaps survive on an airship, you can not expect hydrogen containment to be perfect. They would have to frequently stop, collect tons of fuel and appropriate minerals to melt rocks in large, and specially designed kilns that can capture the escaping gasses, then run compressors that are frankly WAY past medieval technology to separate the hydrogen from other gases. They would also need to maintain the compressors which is a whole other technological hurdle.

This is not even including what other resources you may need like a regular supply of proper lubricant's, waxes, patching material, and what ever else you may need. In short, airships NEED a sedentary port of operations to provide for all of its many needs which a nomadic life style can not provide. Not only would these things make it easy to be taken away from your preferred environment for food, but they would also take you away from your preferred environment for producing hydrogen gas as well!

## How to Improve the idea

For starters, switch from hydrogen to hot air. While a hot air balloon may seem like more maintenance because you are always burning fuel to keep it in the air, you can afford to be much less selective in your fuel source. Your nomads could burn pretty much what ever they find be it wood, grass, coal, etc. to keep them aloft. This also removes the need for industrial era machining, to be able to make and maintain your compressors.

Second, they need some way to control where they are going. This means you need some manner of propulsion. Since you are already burning wood to keep your airship aloft, it does not take a lot of ingenuity to find some way to convert some of the updraft from the flame into propulsion using a simple windmill/propeller system. You will not get the sort of thrust you may see out of something more advanced like an internal combustion or steam engine, but that is okay since you really need to move fast.

So with these two changes, you now have a viable nomadic life style: You can choose where to go, and you can be flexible with what you find when you get there. This just leaves 1 very important detail to address before we can answer your actual question. Why do your nomads invest so much time and effort into building and maintaining expensive hot air balloons instead of going by foot or draft animal?

The best answer I can see for this is a very long and inhospitable migration route. Most nomads do not move around randomly, but choose to travel between known spots that are good to be at different times of year. Many nomadic tribes would travel back and forth between places that may be good hunting grounds in one place for winter and good foraging grounds in another place for summer... but what happens when you put a harsh environment like a mountain range between the two? Normally this could be deal breaker because the trip would just end up killing too many people to make, but if each good spot is adequately bad at the wrong time of year, these nomads may have to make the trip anyway. So for many generations, this tribe makes the trip, with people dyeing along the way until someone discovers they can fly using hot air. So, they start making the trip by hot air balloon saving lives and justifying the cost.

By going with a mountain range as the dividing feature, you provide a landscape that is dangerous to pass by foot, easy to pass by balloon, and should have enough trees that on a long journey you can set down to gather more wood as needed.

So to answer your question, they do not gather food from the air, they transport the food they need while traveling, but they use their airship to go to where the food is at different times of year.

• you can't tack with airships.
– ths
Nov 17 '21 at 17:54
• Expanding on the comment from @ths, tacking uses the opposing forces on the keel and sails to be able to redirect the energy from the wind and move the ship in a different direction than just with the wind. Without a keel in the water, an airship can only travel with the wind. Nov 17 '21 at 19:32
• @MichaelRichardson I do not know of any experiments that prove or disprove that you can tack in an airship, but even with opposing forces, you can not move forward with the sum of a static and backwards vector. The forward(ish) vector is caused by the same principle that allows an airplane to fly. The shape of the sail when turned more or less into the wind creates a suction on the windward face pulling the ship at 90deg to the wind; so, if you can face 20deg forward and left of the wind without collapsing your sail, it will pulls you 70deg forward and right of the wind. Nov 18 '21 at 16:25
• I think the real limiting factor here is not that you need your a keel in water, but that sails big enough to work would have to be prohibitively large. Nov 18 '21 at 16:25
• @ths In case you are right, I've added an additional suggestion that could achieve the same thing if one is willing to slightly bend the rules on "medieval" tech, which I think the OP is willing to do since he already suggested hydrogen balloons. Nov 18 '21 at 16:55

## By Landing

Unless I'm missing something, what is stopping your airship nomads from landing? Historic nomads followed wild herds or shepherded their own, and gathered wild produce from the land. This means moving mostly with the seasons- not every week, or necessarily every month. This also meant their movements were cyclical.

Airships are good for travel, but chock full of logistical challenges for daily living. To be the most nomadic, they could land to hunt food and prepare other supplies weekly at minimum. To be less nomadic (but much more unique), they can cycle between multiple established, resource-rich settlements which other peoples can't reach because of distance and geography. The numerous permanent implements for daily medieval life - looms, mills, wells, forges, wood shops, storehouses - all stay on the surface, patiently waiting for the next time their owners visit

It depends how easily they can change elevation/land, and at what cost. Without effective propulsion they can still change direction by picking up different air streams moving in different directions at different levels, or land and take off for trading etc... but to do that they need to be able to change elevation cheaply and easily. That basically means either doing so without valving lift gas or their lift gas being so cheap, and widely available, that they don't care how much they use. Neither of those is easily justifiable with technology available in the historical period you've elected to work from.

If they can't change elevation/land cheaply for trade and hunting etc... then you're going to have to look at enriching the airborne biome to the point where it can sustain hunter-gather type activity by small groups who are permanently aloft. The sky would have to have a similar travel rate calorie density to that of a neolithic forest, that is there would have to be roughly the same amount of available food calories per hour of travel along the steerable routes as what used to be obtainable in the old-growth European forests that my ancestors used to inhabit. Hunting and/or gathering might be aided by available technology but unless they can farm the sky that would only lead to depletion of food resources see what happened to whales, herring, tuna, wolves, beavers, anything else we nearly hunted to extinction.

Lots of good advice pointing out the big flaw where do they get the gas?

So, to make this interesting, I'm going to give your world one big difference - it already has floating sky animals. (Am possibly inspired a bit by the Gossamers in Wen Spencer's Elfworld). These sky cows have different intestinal flora that generate hydrogen and there's an equivalent of krill that floats.

There may also be lower gravity that makes this all a bit easier.

This reduces the navigation issue - there are bands of sky krill in the prevailing winds, so it becomes a closer maritime analogy than you may have started with. A semi-agrarian but more hunter/gatherer society can drift in these winds.

The Wooden hulls could be light timbers such as bamboo which gives interesting scarcity issues - finding a good timber crop on a mountain.