this post was submitted on 04 Nov 2023
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Noise is absolutely a concern for flying things. The reasons we don't yet have flying cars is not because they're too expensive, but because they're too loud. And this is specifically why the FAA won't let me commute to work in an ultralight.
The police want Bladerunner spinners so bad they can taste it. And the reason they can't have them — or more helicopters — is the noise.
That's not the only reason why flying cars haven't arrived. Getting a license to fly is about the price of a new car. Bad weather is no flying. Air Traffic Control can't handle thousands of commuters. Flying cars are pretty big so parking is going to be even more of an issue.
Also, imagine drunk flyers in bad weather.
Ground traffic collisions can also cause collateral damage, but more often than not those are constrained to the roads or their immediate vicinity where not many people live. An aerial collision may happen above residential areas, and even slight fender benders may mean a double crash (...on little Timmy mowing the lawn).
Also, there's no air bag in the world that can save you in a crash.
Road traffic is easy to direct and regulate with road signs, lanes, lights, painted lines. Good luck herding cats a hundred (hundreds of) yards above ground. It's not a huge problem with planes because there are not as many of them and they fly at vastly different altitudes. Not the case with personal flying cars.
With ground traffic, you only need two blinkers (or two sets). Some drivers even struggle with using that two properly. Good luck for getting them to use more.
And that's just the top of my head, I'm sure there are like 2634 other reasons.
They're working on next generation air traffic control, that is automated and also can handle drones whizzing around next to flying cars, but developing that isn't fast or cheap or deploy and will need extra equipment on the ground and in the cockpit.
...and that's still just for the drones.
I can't imagine an "open to the general public" flying car system that didn't involve huge amounts of automation, basically self-flying planes. A modern jet liner is effectively self-flying already. And, even though the pilots are rarely required to take direct control over the jets the alcohol limit is 0% and they're not even allowed to drink within 8 hours of a flight. So, to have a scenario with "drunk flyers in bad weather" you'd need a system with looser rules than current aviation, and less automation that current aviation.
No, but there are parachutes.
Besides, most fiction involving flying cars also involves automated flying cars. Sure, often the "hero" takes direct control of the car and does some crazy maneuvers with it, but in the futures where flying cars exist, autopilots are extremely advanced, and most commuters just hit the button and relax. In addition, if an autopilot did exist, it could become "driver assist" if the human decides to take "direct control". So, even in a future with frustrated aerial commuters who get "sky rage" and decide to take over flying from the autopilot, a "pilot assist" program could still interpret what they want and limit the danger they pose to themselves or other craft.
The F-16 is almost 50 years old now, and for those 50 years it has been impossible for pilots to fly it with "assists off". The plane was designed from the start to be dynamically unstable. A pilot simply couldn't control it without computer assistance. The pilot uses a fly-by-wire system where their inputs are interpreted by computers that do the right thing while still maintaining stability and so-on. A future flying car would pretty obviously be designed the same way.
Yeah, as I was writing that, I was thinking about '80s flying car lanes. It's like a flow of cars with constant speed. But the 'drunk flyers' bit meant that we are humans. You're also not allowed to drive drunk on the roads. That doesn't prevent people from still doing that.
Good that you've mentioned the F-16, I'm just watching a video on them by Real Engineering on YouTube. I can only recommend the channel, and I'm not even an engineering nerd. Well, not yet.
EDIT: Yeah, a few more minutes into the video I think we both watched the same : ).
I haven't watched a video on the F-16 for ages. I am just an aviation fan and have heard many stories of the F-16 over the years.
I don't know if it's mentioned in that video, but the early days of the F-16 were really interesting. It was the first ever fly-by-wire fighter, so there were lots of design issues to work out. The very first versions of the F-16 (maybe still the YF-16 at that stage) used a side-stick that didn't move at all, it was designed to be pressure-sensitive so pilots could pull lightly to put a little bit of elevator pressure on, or pull hard to go to the elevators' max deflection. The problem was that pilots never knew when they had reached the limits, so they pushed as hard as they could on the stick. Observers said that you could actually see a twitch in the control surfaces when pilots were at the max, and the twitch was due to being able to see the pulse of the pilot.
After a short time, General Dynamics switched to a side stick that had some range of motion, so that pilots knew when they were at the limits of the controls and didn't keep pushing.
Yeah, they mentioned it in the video. That whole plane is just an awesome thing. It's crazy how many modern sounding features they could shove into it so long ago.
As for the stick, AFAIK the pilots couldn't tell the difference between moving it with 40% or 60% of the force needed, and the feedback loop was delayed.
I guess it's just the timing then, because these were the main points of the video too.
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The amount of energy required to keep something in the air instead of using the ground is also astronomically bigger
Not really. Many planes can get about 20 miles per gallon traveling at about 180 miles per hour. That's slightly more than a family car, but not astronomically more.
The big differences are that there's effectively no "traffic" in the air, so once you dial in a cruise speed you stay at that speed for the entire flight. In a car you can get stuck in stop-and-go traffic. There's also the lack of "rolling resistance" in the air. Even if you're going a steady speed on a highway your tires are a source of drag. On the other hand, taxing and taking off can burn gallons of fuel, so unless you're going for a fairly long flight that's a significant part of the fuel burn. Also, planes go in a straight line, whereas cars have to follow highways. But, the total fuel cost of the trip really includes the trip to/from the airports.
But, fundamentally, the fuel economy of cars and airplanes is pretty similar.
The average person can barely drive without murdering someone. Flying is even more complex than that, the noise is just a small problem compqred to that.
Flying cars would almost certainly not be directly piloted. Even in movies, by the time humanity has flying cars, it has automation to handle those flying cars.
We have flying cars, they are called airplanes or more specifically civil utility aircraft. You know, like the Cessna 172.
Flying vehicles aren't more mainstream because of the cost. A new plane can cost over half a million dollars while a used plane can easily be over a hundred thousand dollars. And that's just the cost of the plane.
The other reason is because the rules are more strict and are actually enforced. If a pilot flew their plane like the average person drives their car they would be sitting in jail await trail for attempt murder.
I think you're missing the cars part of flying cars.
Like, the dream isn't to drive your car to the airport and get into an airplane. The "car" part of flying cars is about having one in your driveway.
You can get a used Cessna for under $60k:
https://www.trade-a-plane.com/search?category_level1=Single+Engine+Piston&make=CESSNA&model=175&listing_id=2421983&s-type=aircraft
https://www.trade-a-plane.com/search?category_level1=Single+Engine+Piston&make=CESSNA&model=150L&listing_id=2420732&s-type=aircraft
https://www.trade-a-plane.com/search?category_level1=Single+Engine+Piston&make=CESSNA&model=150H&listing_id=2423454&s-type=aircraft
But, the issue isn't the up-front cost. Because a plane isn't a flying car, you have to store it somewhere, and that isn't cheap. Even just tying it down outdoors can be more than $150/month. Then there are the operating costs, which are much higher than cars: insurance, annual inspections, fuel, maintenance, etc.
The Webster dictionary defines a car as a vehicle that moves on wheels which airplanes definitely are.
You can have your airplane in your driveway (or more commonly your grage). They are called fly-in communities and are more common than you think.
If you're having to resort to the dictionary definition, you know you're flailing.
The idea behind a flying car is that everyone could have one in their driveway (not the rare people who live in fly-in communities) and that they can use a combination of driving and flying to get places. That's what all the flying-car companies are working towards, that's what people dream of having. Having to live right next to an airport, or having to drive their car to the airport to get their plane isn't the "flying car" dream.
I'm sure being too loud is an issue, but it's not the issue. That's like saying the reason we don't all have castles is due to municipal zoning laws. Sure, that would make having a castle harder, but it's not the issue.
Yes, "flying cars" are loud, but that's a minor issue compared to the other ones. They're expensive to operate. They're dangerous both to their passengers and to people on the ground. They're extremely expensive. The infrastructure isn't available. They'd require training to operate, etc.
If you could wave a magic wand and make all those other problems disappear, the noise issue would still be a blocker. But, the noise issue isn't the biggest current blocker.