How do I prevent flight in a cyberpunk future?

Question

~200 years into the future, most of mankind has been wiped out by war. The remainder lives in walled supercities, to protect them from the hazards of the wastelands - including a nation of machines intent on human extinction. I've been thinking of ways to give the humans a fighting chance, while also restricting long distance travel, one of them being to remove flight from the equation. This includes missiles, rockets and aircraft.

In a world where cybernetic mods, artificial intelligence and genetic engineering are day to day things, what reason would there be not to have any form of flight?

Edit: For clarity by aircraft I mean planes, helicopters and drones. Airships and gliders are slow enough to be shot down by almost anything so they don't matter.

Basically no faction should even want to consider investing in aircraft.

So I am seriously amazed by how much feedback this question got - you guys are awesome.I've chosen Tim B's answer because I feel it is the most comprehensive way to prevent all flight. Kudos to the AA platform ideas too, as well as the gen-modded attack birds.

Answer 1

In a last ditch effort to prevent extinction (possibly one that worked, after all people are still here) a team of scientists released a swarm of nano-machines into the atmosphere. They form a slight (insert colour of choice) haze in the air at a height of X meters above (insert sea level/ground level/some other measure/do you want to allow skyscrapers or not?). They rapaciously attack any material object entering the swarm and use the raw materials to add more machines into the swarm.

The swarm was created by technology lost in the war, so it is beyond anyone currently alive to defeat it.

Answer 2

How about active volcanism? Clouds of volcanic ash can make long-distance air travel essentially impossible. Like they did in Europe a few years back.

There are definitely geologic processes which can supply volcanic ash indefinitely. For example, mantle trap eruptions. You can also blame a lot on them in the area of climate change, ecological disarray, large areas of Earth turning inhabitable, etc.

What's more interesting - some military/general aviation flights might be possible, just not passenger long-range aviation.

Answer 3

So if just people aren't flying, then the machine nation can use EM cannons to knock down any form of powered flight. You could also have rival cities knocking each other down using EM cannons.

If you want to go REALLY crazy, you can design an aerial supercity, built solely by a rogue, but benevolent AI, that leaves everyone else alone until they enter a certain altitude. This way, all powered flight technology will be in the hands of this Aerial AI, and anyone who tries to reach any sort of useful altitude will be mercilessly shot down.

If genetic engineering is the norm, packs of hybrid, cybernetically enhanced birds, released by mistake, could hunt down vehicles in flight, in a similar fashion to the above idea.

Then again, if resources are scarce, you can always be forced to rely on some form of energy which is too inefficient to assist rockets/missiles/vehicles in flight, but that might defeat the point of having a cyber-punk era.

Answer 4

During the war thousands of orbital laser weapon platforms were launched. They target any aerial technology such as aircraft, drones, helicopters, missiles and rockets. These satellites were primary antiballistic missile systems but also possessed the capacity to destroy aircraft as well.

Since this two centuries the laser orbiters are extremely advanced. They can repair and maintain themselves. The Earth-based automated infrastructure to support the orbiters continues in well defended sections of the wastelands. The orbiters can change their orbits which will prevent aircraft flying during windows of opportunity when there aren't any orbiters overhead to bring them down.

This is essentially an advanced version of Strategic Defence Initiative, but one that actually works, is capable of precise targeting of structures and vehicles located on or near the surface of the Earth. Obviously, air vehicles of any kind are no exception.

This system has the ability to locate and target air vehicles anywhere on Earth. Particularly, if there are orbiters placed in higher orbits to give them greater overview of the Earth's surface. There is little chance that flight can take place in safety effectively anywhere on the planet.

Answer 5

Simply penalise energy.

Either there are no highly concentrated energy sources available - we've simply run out of oil - or our laws prevent us using it - high carbon tax, and biofuel use would mean people starve, there isn't enough farmland for both. Or go back to 2012-14 oil price trends and extrapolate them for the next four years...

(Nuclear - if you allow it - is a bit too heavy to fly!)

Cybersystems are OK - solar cells can run them easily, with near-infinite lifetime storage for tens or hundreds of Watt-hours (look at LTO cells if you need practical details - lithium titanate batteries can last 20000 to 50000 charge cycles - that's a century at one or two charge cycles a day).

So, our practical systems run on relatively low power - hundreds of watts tops - we can stay comfortably warm - or cool - through solar heating or heat pumps - electric bikes are pretty similar to current highway speeds and their LTO cells safely recharge to 80% in six minutes - but there are no energy sources left powerful enough to sustain flight.

Sure, you can run up a mountain and jump off with a hang glider, and the solar cells in its wings can keep you aloft at about 40mph, but it's too flimsy for anything more than summer afternoon recreation. Flying around the world on solar power - as today - is a stunt.

Practically, the only way round this limitation would be liquid hydrogen, which has its own problems : if you can't smelt a high enough grade of steel any more to make a completely flawless pressure vessel with vacuum walls (think Thermos flask), it's practically impossible and hopelessly dangerous to try.

We still have high technology - we can refine and process silicon objects up to a foot across - basic solar cells, as well as all other semiconductor devices - and if that goes wrong, nothing big explodes.

What we're missing is massive scale - and again, high energy density - plant like a steelworks. More because we no longer need such obsolete technology, and nobody's willing to dig up the coal, than because of its inherent impossibility.

Answer 6

The Robots have wiped humanity because they are equipped with the highest-end Ground-To-Air weaponry. They have impressive tracking system, adaptative ammo, heat-sensitive missiles, and an excellent perception. You just can't fly over without being detected, and if you are detected, you're going down.

Their Ground-to-Ground weaponry is strong, but clever thinking can beat it. There's however no way to beat them in the air.

Answer 7

Consider a variant of MAD: both humans' and machines' survival completely depends on certain structures extremely well protected from ground attack but extremely vulnerable to aerial attack. Consider as well that both sides have the ability to wipe out other party completely but doing so will result in "dead man hand" attack by other party. Both parties know that pursuing flight or even being perceived to have means of flight or attempting to fly will be considered as a mortal threat and will trigger an immediate all-out attack by other side. So now you have both sides extremely reluctant to go that way.

Answer 8

Gravity Pockets. Since the war was brutal and global, with use of subparticle weapons, strange eposodes of gravity anomalies are popping up randomly. This makes every aircraft to sooner or later experience the fate of intantanious stone-like falling down and crashing. Or if flying between these pockets - randomly imploding in the air.

Make it that the gravity anomalies pop up higher above the ground, this way only aircraft would be affected. :)

Answer 9

World Wide No Fly Policy

A city & world-wide array of very long distance laser cannons could detect any airborne movement and shoot it down from far away. Space-based satellite laser reflectors can allow stationary high powered lasers to take aim at targets even over the horizon by shooting up at the sattelite reflector which then directs the laser down onto any target attempting to take off.

Answer 10

A different way to go about it, without resorting to advanced technology, would simply be the proliferation of Manpads (portable missiles like Stingers) that can target aircraft. These are a big issue now, with the US and others worried about them falling into the hands of terrorists, so in a post-apocalytic scenario they could be widely available to wasteland dwellers who use them to shoot down anything that flies to scavenge the wreckage. The missiles payloads are small enough that they aren't really useful against your walled city (if the walls are thick and high enough). So while the technology for flight exists, flight would be too dangerous.

Answer 11

Entirely removing flight above a certain altitude would be difficult. At minimum it would certainly devastate the bird population. Gliders for low energy environments. Rockets for vacuum environments.

Atmospheric shield

Within that 200 years, something went wrong causing the planet to lose atmosphere. A planetary shield was built. It doesn't follow the terrain contours, intersecting with mountains and such. It's ovoid in shape, keeping with the average ovoid shape of the planet. It only keeps gasses in; liquids and solids can get through it. Now that 200 years has passed, the shield still works but there's no atmosphere above it.

Artificially Intelligent, Self Replicating Anti-Aircraft Guns

The thing about AI is they are single minded and goal driven. The goal they are built on is the one they optimize for. The planet, at one time, needed a really good AA defense. One was designed and built. It includes factories and mining capability oriented towards the ability to replicate and upgrade. It's only interested in keeping the skies free. It's constantly building new, better AA emplacements. Birds were considered necessary at the time and it was easier to "teach" the AI to shoot down fast flying things rather than teaching it to differentiate between a bird and a slow drone. Localized defenses around the emplacements prevent sabotage.

Decades later, they have AA beyond anything the current population can design. It's entirely AI driven and, after a long period of getting stuff shot down, nobody bothers with high speed aircraft any more. (Though there is a kind of race to see if one can build an aircraft that is faster than everybody else but won't be targeted by the AA. It's very entertaining. Occasionally somebody produces something with a combination of dexterity, speed, and stealth needed to avoid the guns and win a race, but it doesn't last very long before the guns advance enough to take them out, usually a few days. The bets on how long they'll last can get pretty high.)

Technological Singularity

There's no flesh and blood people ever since it was discovered how to upload your brain. It's been like that for 200 years. I was one of the first generation. I remember what it was like but it's better in here where you don't have to hurt or grow old or see family die. We still have our wars but they're done in the Games now. Everybody wants computing power and memory space so those are the rewards but everybody works towards creating more computronium. Though, it's mostly automated now.

I do miss somethings. Space doesn't really exist anymore. Sure, you can go out there, but there's nothing to go to. The stars, the planets, our sun, they're all just paintings on a background you can never reach.

Flight is limited but it's not such a big deal since you can just teleport everywhere. There's no supersonic aircraft since they eat up terrain generation CPU time like crazy. Biplanes are fun but they don't get very high. (The Realists say it makes things more realistic, but the rest of us know it's because the governments use the clear areas for top secret research and such.)

Most people today don't know it, but they never quite got the taste of chicken right.

Answer 12

Here's a stalemate. The outer earth has become a prison planet, conquered by a rival civilization (Civilization B) who migrated to space during the war and enslaved (or brainwashed) much of Civilization A. The survivors of 'A' kept themselves from falling by simply holding off 'B', so the war never ended, but they've adapted so well to the condition that they've been able to thrive and grow as a technological society. 'A' developed massive colonies and pathways underground as a means of holding of 'B'. Flying is the easiest way to get detected by the security system covering the earth. Equally detectable is B's bots when attempting to access A. Stalemate ;]

Answer 13

Assuming they have any means to control weather, you can explain "world-wide no-fly zone" in a way similar to "The Matrix" movie:

Corporations build lots and lots of data centers => there is not enough space below ground, so they build skyscrapers of data centers => building above ground means no earth for countering interference (for example, UV rays and solar radiation) => corporations use heavy clouds to block sun and radiation from space => (optional) something goes wrong and these heavy clouds become storm clouds.

Not the greatest explanation, but hey...

Answer 14

The WMD used during the war disrupted climate balance - the weather is violently and chaotically changing, with bursts of wind, rain, hail, tornadoes etc. Nothing that we do not have today, just more frequent, sudden and completely unpredictable. This makes flying extremely dangerous and generally not worth investing into.

Answer 15

Architecture. Small, tightly packed roofs of varying levels would make landing a pain. Also having layer cakes of construction mean you can't actually get to the places you want to go to by air.

Better alternatives airplanes might be kinda obsolete when you have high speed trains that are just as fast. You might have exotic ground effect craft that're just as fast and silent. Also, less likely to hit a building.

Geography and weather Massive geoengineering projects littering the wastelands, making level flight implausible. Great huge storms of dust clogging up engines - like that icelandic volcano. Have them random enough (or have man made ones as a standard weapon) would stop airflight

Answer 16

My 5 cents:

Microparticles from the war

Advanced materials used before the war had the unfortunate side effect of crumbling into microscopic particles that are both sharp and light, making them hazardous for anyone flying (or driving!) into a cloud of them. Open areas with strong winds could cause particle storms equivalent to sandstorms to form even on short notice. These storms could easily rip apart anything, be it flying or not.

Dust clouds, smog etc.

Clouds that block so much sunlight that solar power is not really an option and other sources of energy are better used in heat production. Also the clouds could contain something that block conventional combustion engines, like particles, dust or something similar. Maybe even something a bit flammable to make rocket engines hazardous too.

Other notes

Anything you do, keep it logical and don't let yourself get caught up by something completely fake. Don't make long distance flight completely impossible. Admit to your audience that it could be possible, but in the current circumstances it is not feasible or would need considerable effort, and would probably result in the craft being detected and intercepted by opposing factions.

Keep it simple. Don't overdo it by adding something too deus ex like orbital cannons destroying everything that lifts off by 5 meters or something that complicated. You just end up with questions like where they get all their power, how can they watch every nook and cranny all the time and so forth. And in the end you probably forget their godlike abilities at some point and make the plot illogical. The element that hampers air travel should be something so integral to your world that you can use to explain many things, not just the flight part.

Answer 17

Due to extensive damage to the ozone layer, a rare natural phenomenon has occured that has severely lowered the existing layers around the earth to ensure the thickness can be maintained without holes inside. As a direct result of this phenomenon, all existing layers around the earth have been cramped together, and instead of the regular kilometres- they only take up a distance of 5km apart. (the ozone layer, being in the stratosphere- is now only 6-8km away).

Due to the nearest layers being so close to earth, the amount of oxygen in the top layers of the earth is so thin nothing like a conventional engine can function on any altitude above 5 km. This restricts all use of conventional air planes.

The reason why the air planes can't function at that altitude is simply because there's not enough air to hold them up.

http://spaceplace.nasa.gov/review/dr-marc-technology/rockets.html

Answer 18

Fossil fuels have been completely depleted, or are located in areas that for some reason can't be accessed. Even though other technologies have advanced, there has been no breakthrough regarding battery power, so batteries are still heavy and have low power density. This means they are not useful for flying, or are limited to use in ultra-light glider-like planes, which are trivial to shoot down.

Answer 19

Two options:

Either the population on earth increased so much that flying for any particular individual would be seen as unequal in society, rendering it impossible without public outcry. That is "why can that person fly but not me?" and everyone not being able to fly due to the immense population size.

The other option is that earth's magnetosphere has wakened and flying would require extensive shielding from radiation. This would either be too expensive or even impossible, weighing too much or some similar explanation.