There's no space to construct a runway. Are early planes still useful and promising technology?

Question

My setting exists on a huge vertical cliff with no top or bottom, and currently nearing the end of an steampunk-y industrial revolution, putting its tech level somewhere in the range of 1860s to 1910s. Everybody lives on relatively small and thin ledges or spaces carved out of the rock - the largest are up to 1km wide, but also heavily developed with cities, farms, etc, and too valuable to waste on airports.

They use airships to move cargo around (steam-powered hydrogen zeppelin types, with a couple of handwaves to explain abnormal lift capacity), but the technology level also is such that heavier-than-air aircraft should be at the very least discussed as a possibility already.

You can launch one by just pushing it off the cliff or dropping it from an airship I guess, but seemingly there's nowhere for this aircraft to return to, since there's no space to build a landing strip long enough to safely land on ("safely" even by the 1900s standards of safety).

In this environment, will airplanes be practical to use and develop (and threaten to replace airships)?

Answer 1

If you want something that will be more colorful and relevant to your own setting, heavier-than-air vehicles could be thought of as VTOL things: to launch them, you drop them. Only natural, it's how paper darts/planes are doubtless launched. But to land them, why would their first thought be a horizontal airfield?

They live on a cliff. To lose velocity in something moving there are two options: crash into the cliff (not good), or fly vertically up the cliff until they stall.

So, grab dangling winch cable and then fly vertically upwards until velocity is lost. Done right, winch should be able to reel in the loose cable and match speed with you as you slow down, so that the slowing plane stops being a flying thing, and becomes an object dangling on the end of a crane.

Impractical? Maybe. But VERY cliff-punk.

Answer 2

The first Carrier landing was 1911:

Now, in terms of space, that looks to be about 20-30 metres. 1911 is 1 year after the upper-limit of your tech level, however, I'm going to say that this was a function more of 'no need', since there were large areas of open field to land in - whereas in your world, this would be a primary requirement and so would have received greater attention for the problem.

In short: Yes, they would be useful. The technology to successfully do this existed in 1911 and so it completely in the realm of what you outlined.

Answer 3

Airships were aircraft carriers

Just after your world timeframe aircraft were launched and landed in airships. It is perfectly reasonable to make an airship your airport. And it’s cool!

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If your traffic isn’t too heavy you can use an airship as an aircraft terminal. It sails out to launch and catch aircraft.

But you could be right as well, living on a cliff, they may simply skip the airplane altogether. Airship technology eventually carried us fairly fast, and they had huge payload capacity. There are dirigibles today which can literally move a house! Australian company SkyLifter plans services that include moving aid or even portable hospitals to remote areas - like rural regions or disaster zones - that have poor infrastructure.

Answer 4

Absolutely!

Someone will definitely figure out about heavier than air transport, because air transport is important to this setting. There's a huge incentive to improve flight technology.

Flaps

Landing will take some space, but not too much. Birds flare their wings when they land on a branch to bleed off speed. Assuming your setting has birds and trees, someone would see this and steal the idea. Oversized wings (to allow low speed flight) and oversized flaps (to kill the remaining speed) would be used to slow the aircraft down and minimize run-way requirements.

And/Or "Tailhooks"

A zero-length runway could involve hanging a loop of rope from a ledge, and catching it with a hook, sort of like a carrier landing in our world. If the rope can play out with some resistance, then the pilot can cut the engine, lower the flaps, and fall until the rope reduces the speed to zero.

I don't know that I'd want to be the first test pilot, but if space is at enough of a premium it would occur to someone!

Answer 5

It's plausible to some degree. In large air carriers they "catch" fighter planes, which fly with a considerably higher velocity than 1910s airplanes, with a hook, more specifically a tailhook. Maybe something like that could work if the plane is small enough.

Another idea is the ornithopter. I don't know much about it but it was an idea that was always in the background as a potential flying technology until the airplane sort of "won". But why not? Maybe your civilization can develop something like that. People experimented with ornithopters in the 1910s for sure. Here is a modern ornithopter for fun.

If airplanes develop, I think they'll win over the slower airships in your world.

Answer 6

Too valuable to waste on airports.

FRAME CHALLENGE: This makes no sense unless your world also cannot justify land for roads, paths, or rails.

Air travel's benefit is that it only requires the space of a runway, and for that small amount of space you can cover a far greater distance in less time than road or rail. If your world cannot justify space for a few runways, then it also cannot justify space for roads, paths, or rails which collectively consume far more space and allow travel over much less distance at slower speeds for the space consumed. Therefore the reasoning that the land is too valuable to waste on airports to the extent that you would not even build a single runway holds virtually no water, especially if your ledge cities are some distance away from each other. That would justify one runway per city.

A few runways would enable the society with a unique capability, and what you would be giving up is a small amount of land that would be otherwise be used for facilities which already exist elsewhere. Instead of a dozen farms an zero runways, you would have eleven and a half farms and two runways since a farm is far larger than a runway.

The aircraft in your specified time period also did not require very long runways compared to modern aircraft.

Answer 7

Powered Gliders

I could easily see aircraft evolving from gliders in this setting, a glider or parachute is a fast fun way to descend the giant cliff. maybe even much cheaper than an airship. Someone straps an engine to one to travel longer distances or just to prove it works. this gives you a nice smooth development for more engine power without needing to start with one powerful enough to get full lift.

I imagine gliders and parachutes get invented a lot earlier with the ever present fall risk, so the development might not even take much longer.

Answer 8

If you don't have to start out above your landing site to land on it, or end up above it to take off, you can land on an upward slope, and take off on a downward one.

Answer 9

Frame Challenge: Space is not actually a limiting factor

Just build the runway OVER the Hangers. Many aircraft carries already take advantage of this idea. In general, both airplanes and airships need about 3 times as much hanger space as is thier top-down profile. The thing is that early airplanes did not need big runways. The first functional aircraft carrier was the HMS Argus which only had a deck space of about 3500m$^2$. By creating a flat top building where the roof is the runway, and the bottom is the hangers, you could fit a runway and hangers for about 20 WWI style airplanes into a 1/2 acre space. Even using modern farming techniques, 1/2 an acre is barely enough space to feed a single human being; so, sacrificing this little bit of farmland would be a pretty small ask for a fleet of 20 planes.

This means that with just a little bit of creativity, you need exactly as much space for airplanes as you do for airships that are as small as airplanes. So, even if your airships were 1000 times as buoyant as Earth based airships, they'd still be in danger of being replaced (or at least supplemented) due to thier higher air resistance and lower top speeds.

Answer 10

Dolven Aetodromes

With all that vertical real estate, your people can easily bore into the huge rocky surface. They could create their aerodromes to any length they need and likely any width or height. Spacious hangars could be bored to either side of the runway too!

The relatively low speed & power of old aeroplanes means relatively short runways and the barn storming skills of early airmen would translate very easily to the skill of approaching a stone wall with a relatively small opening to aim for!

Answer 11

Do you have lakes or seas? Then you don't need runways

Today we think of runways as a basic requirement for planes. It wasn't always that way.

Smooth concrete runways cost a lot to build, and even more to maintain because concrete degrades badly with weather. Aircraft design in the 1920s had advanced far faster than the financial willpower to build runways, and you couldn't achieve the necessary takeoff and landing speeds on a bumpy grass runway. As a result, all high-performance planes were seaplanes. The trophy for speed around a course was a seaplane competition for the simple reason that you couldn't get that performance from a plane with a low enough stall speed to tolerate grass runways. Most major airliners were seaplanes too, partly for the same reason, and partly also because they leveraged the existing port infrastructure and port connections to the rest of the country.

Then WW2 happened. Suddenly national defence in all countries required the construction of vast numbers of concrete runways suitable for high-performance fighters and bombers. Post-war, concrete runways built for bombers formed the starting point for almost every major airport in Europe today, and many around the rest of the world. It's notable that countries without large flat areas of useable land have had problems getting connected to the world airline routes, requiring such extreme measures as reclaiming land from the sea to get long enough runways - a similar problem to the OP's world. And some places such as Canada still make extensive use of floatplanes.

In short (or in Short), floatplanes are your best answer to a world without runways - because they were the answer our world came up with too.

Answer 12

Putting the "Hang" in "Hangar"

Your setting allows for very high power-to-weight ratios in your very lightweight aircraft.
This allows pilots to effectively come to a dead halt hovering vertically in mid-air, which means that the usual means of landing is to hover nose-up under an arrangement of docking-hooks and be attached to one of them. This is achieved essentially using boathooks to manipulate the docking hook onto a loop on the nose of the plane.

Once attached, the ground-crews reel in the aircraft and you're home. The ground-crews can then add further hooks to the wing-tips and tail of your aircraft, rotate you horizontal and lift you into a boarding and maintenance station.

When it's time to leave, the nose and wing-tip hooks are disconnected, and the aircraft is lowered down below the Hangar facility.
To "take off", you are simply dropped into open space once your propellers are spun up.

Answer 13

If your airships have "abnormal" lift capacity, then I suspect airplanes will not be a thing unless they have even more abnormal lift capacity.

Another factor is the the layout of your civilisation: how much horizontal travel vs vertical travel is there? Airplanes are faster at horizontal travel, but airships much better for vertical travel.

Do you have an abundant energy source? Especially for vertical travel the energy requirements of an airplane will be much, much bigger than for an airship.

Do you have rail infrastructure? To me it seems like horizontal railway lines coupled with vertical airship lifts could be a great transportation system.

Answer 14

Remember that early planes often made do with fields and the like as take-off and landing surfaces. Admittedly they also periodically "ground looped" due to the imperfections of those surfaces.

Seaplanes are another possible solution that doesn't need runways. They may need to struggle harder to take off, though.

Answer 15

TL;DR: This question literally asks for a super-heavy dose of a handwavium... There is no way to do it otherwise...

Long answer: ... so the answer is also a super-heavy frame challenge.

First, some problems with the setup:

1. Vertical cliff with no top or bottom means super-strong downdraft and updraft air currents. They alone will make Zeppelins unworkable, as they would probably need to have a mechanism to completely deflate in order to descend...
2. Updrafts and downdrafts are also heavily dependent on time of day and intensity of the sunlight, which has multiplying effect on already insane ones from #1
3. Air currents will provide so much energy via windmills that it will make steam power literally superfluous. Steam engines arose from the combined need for more coal to be mined and not enough manpower, with basically unlimited power from windmills this makes no sense.
4. Steam power requires a lot of fuel and water to work. Especially early engines were super-inefficient (like: used more coal for unit of travel that they could pull). They were slow and heavy, but offered a lot of pull power at low rpm. However, only after refinement and other improvements they revolutionized transportation.
5. Steam power requires a lot of displacement, meaning that - for example - steam equivalent of 12 hp ICE engine Wright brothers used would be almost 10 times larger, weighing maybe 40 times more. This makes development of powered air flight impossible, as I don't see a way to build an airframe sturdy enough yet light enough for flight to support it. But then again, maybe air currents from #1 would help... Anyway, low rpm means not enough rpm for propeller to generate enough power to provide lift.
6. What are the sources of coal and water to feed the always hungry steam engine? Both would be extremely scarce in the "infinite cliff" setup without deep mining (regardless if the shafts are vertical or horizontal).
7. Mining in a hard rock is very difficult - mountains are usually from granite, which is super-difficult to mine without dedicated tools. Where does the steel (which means iron and coal and trace elements) come from to achieve that? Is the setting a "survivors of an advanced civilization" type?
8. Last but not least - farmland. Where did it came from? Farming requires about 2 acres per person if vegetarian, and don't kid yourself if you think you can go vegan. If one of the biggest ledges is 1km wide, it needs to be 8 km long to accommodate that big of a farmland for a 1000 people. Yes, you could do a lot with multi-level farming (top: soil to farm, lower level(s) for storage, composting for fertilizer etc), but to some extent only... You have to have enough fertile soil to start.
9. Going back to airplanes - where does the petrol for their petrol ICE engines come from (assuming anyone comes around to invent one, given that they are superfluous to already superfluous to needs steam)? Wright Brothers Flyer had 12 HP engine weighing about 170 pounds, yet for example 13 HP Gaar-Scott machine weighs about 20000 pounds, maybe third of which is the engine itself... And unlike petrol engines, steam engine gets more efficient the bigger it gets (i.e. compound steam engine). So you have to have ICE petrol engine for airplanes...

Now for the gains of the setup:

1. Due to updraft and downdraft (and it will be mostly updraft), persons could travel between ledges basically effortlessly: just open an umbrella on the edge of that ledge and swoosh! - up you go. Landing on the other ledge can be tricky, but... I'm sure someone will figure out how much lift one person needs to go up and then how big a parachute (if any) needs to be to land.
2. Same goes for cargo - going up is minor problem of big enough kite, going down just requires rough calculation of shape and ballistic trajectory to make the... "jump"
3. Any airplane development could happen around aerodynamically changing configuration: enough wing surface and plane goes up on updraft, retract most of it and it goes down. Literally no need for any kind of engine, just pure physics. And people not afraid of awesome turbulence everywhere, of course.
4. Updraft would offer enormous power-generation capability, which makes lifts super-easy to power.

Without more details on the world you're building only way for you to go is, as mentioned in the beginning, handwavium.

Answer 16

From a purely aerotechnical standpoint, it's not a problem. Short-space recovery of aircraft can be done in any number of ways. Some aircraft have such a low stall speed that they can take off and land in a matter of feet. In the video below, you can see a plane take off in just 15 feet and land in the space of 10 feet. That is just about the overall length of the plane itself, so the aircraft needs essentially maybe 20 feet of runway. And that's a relatively modern plane that is at least capable of carrying a person. By the time it lands, it's no faster than a walking pace.

https://www.youtube.com/watch?v=hPakbghLe38

It depends somewhat on what kind of performance you want your planes to have, but there is rarely only one solution to a technical problem. We use long, wide open runways because we want fast, heavy planes that are easy, safe, and more comfortable to land, but that doesn't mean that runways are the only way to launch and recover planes.

Launching and recovering heavy, fast planes could be a bigger challenge, but still solvable.

The very first plane, the Wright Flyer, was launched with a catapult. The engine was underpowered- so it could sustain flight but the aircraft could not take off by itself. In early attempts they could use the wind to get the Flyer airborne, but wind was not a reliable method. The catapult was a small tower with heavy weights and a pulley and rope system- when released, the weights would pull the Flyer about 50 feet along a rail at which the pilot nosed up the plane and would become airborne. This is a neat approach for your world, because you're trading horizontal space for vertical space by using a right-angle pulley. Modern aircraft carriers use catapults driven by steam and electric motors rather than dropping counterweights.

Landing a fast/heavy plane can be done in different ways. Others have already mentioned tailhook systems used on aircraft carriers. Those systems also have a crash net that can be used in the event the tailhook fails (but nets + propellers or jet engines is a bad time). Entire aircraft have been landed with parachutes. They have been snagged out of the air by moving arms. They have been stopped on short runways by using retrorockets.

Answer 17

Just buy some land.

There isn't "no place to land", as the scenario is described there are many square kilometers of flat space, the problem is just that they're already occupied. This is just another resource-based challenge of developing powered flight that's no different than obtaining any other resource like metal, fabric, or gasoline - you just have to pay for it. The Wright brothers invested thousands of dollars of their own money obtaining the materials to build their airplane, not to mention the value of their years' worth of work. Potential inventors of the airplane in this world just need to invest some money in land in addition to materials and labor. The invention of the airplane already required overcoming a significant financial barrier to entry, buying land is fundamentally no different than buying anything else you need to fly.

The only way this doesn't work is if land is truly a priceless commodity that can't be bought or sold for any price, but that doesn't really make sense on a world of infinite scale where the livable area can indeed be expanded, albeit at some cost. This might slow the development of the airplane as it will result in an additional cost that wouldn't otherwise be present, but at some point, someone will deem buying (or creating) 0.001 square kilometers of flat space worthwhile.

Answer 18

Autogyros! Also known as gyroplanes, gyrocopters, and perhaps other names.

People figured out the basics of vertical flight long before helicopters were practical, they kept running into control issues if power was applied to the main rotor. Later on there were improvements in materials and machining to allow for cyclical control of blade pitch and blades that were flexible and yet strong enough to hold up to the forces imposed by such an application.

Autogyros show up in some steampunk fiction because they have that "look" of technology from about 1900 to 1920. They aren't all that practical if there's a runway for takeoff and landing so they died out pretty quickly. If there's a cliff to launch off from then getting the forward motion for vertical lift is possible. When needing to land the need for forward motion is not necessary, the aircraft can come in to land by autorotation of the lift propeller.

I have seen unmanned airplanes make a vertical landing by use of an oversized propeller and computers to aid in control of the flaps, elevators, and other control surfaces on the airplane. My guess is this worked because there was enough air over the control surfaces to allow diversion of some of that airflow to prevent the airplane from spinning like a helicopter that lost it's tail rotor. Maybe with some practice, an airplane optimized for this maneuver, and a bit of "handwavium", this is possible with a human on an airplane using 1890 to 1910 technology. Some application of the autorotation might help in this too.

I'll agree with other answers that with things like arresting wires on landing, catapults on takeoff, taking advantage of headwinds/updrafts/etc., skilled piloting, and other techniques used on early aircraft carriers that it would not take too much "handwavium" to make it plausible for airplanes to work in tight places. If space is too tight for even those options then perhaps an autogyro is what would fit. Flying up a cliff face and then drop power for the plane to fall onto some kind of hook to catch it might work. That's taking some risks though, far more than some kind of autorotation on an autogyro. At least given what I know of aircraft, and that might not be saying much.