I think in the case of flying taxi's is just that it is a moronic idea tho.
I expect the exact same is true for birds - the kinds of effects that allow birds to fly with so little energy compared to a propeller-based aircraft are almost certainly not scalable, due to the fundamental properties of air as a gas. As far as I know, bird flight is made possible by complex turbulence effects induced by the microscopic structure of their feathers. It's very unlikely this effect could skale to 100kg of weight.
Piloted ornithopter: https://www.youtube.com/watch?v=a-qS7oN-3tA
Human-powered ornithopter: https://youtu.be/0E77j1imdhQ?si=Dd5hLla27Pz8gJNe&t=100
Also, Quetzalcoatlus northropi could've been powerful enough to carry a human.
The dream of “order a flying taxi on your phone and it takes you wherever you want in five minutes” isn’t really compatible with aviation safety culture (at least at the pilot level in the US). That’s not to say it can’t be done, but you probably need a lot of really good PR people to figure out how to say “we want to remove the safety controls from this so we can make money with it” and have people buy it.
¹one of the few times the US has been forced to back down admit fault, and agree to changes. https://www.usatoday.com/story/news/nation/2025/12/17/united...
Maaaaybe instead of the tunnels and bridges, to increase throughput during rush hours, but even then we’re trying to have fewer vehicles in Manhattan, not more.
Also, I cannot imagine what it would be like to go through an intersection during the winter. You would be hit with a wall of cross-cutting wind tunneling down 50 blocks that no airborne device is going to handle well. Absolute nightmare.
That's where the problem is.
When Airbus was doing the math on these a few years ago, the pilot cost was also one of the main concerns, so it was "autonomous or bust", and they ended up investing a lot on the autonomous side (not just the aircraft but also urban traffic management, etc).
https://en.wikipedia.org/wiki/2025_Potomac_River_mid-air_col...
Literally any failure of the aircraft means you die.
https://stopthechopnynj.org/safety-and-terrorism/?utm_source...
And yet!
How is that any different from an automobile navigating the ridiculously crowded streets?
In a place with fewer pedestrians I'd buy that airborne vehicles might have a higher chance of hitting a person because they could crash somewhere that a traditional taxi couldn't. But when the place is packed wall to wall with people an arms length away I don't think that applies anymore. At least it doesn't seem self evident to me.
At the same time an aircraft is much more precarious. If anything in the fuel, engine, transmission, props, or control surfaces go wrong it will come down and fast. They have much more potential energy than a car (because they are high up). They also typically have much more kinetic energy because they have to move faster to maintain lift if they are fixed winged, or they have to have fast rotating parts if they are rotary winged.
Even a 20 m flight height means the taxi will reach 72 km/h before it hits the ground.
Would you rather be hit by Skoda Octavia travelling at around 20mph out of control, or a "flying taxi" travelling at 110mph out of control?
Because that's how fast it would be travelling when it fell on you.
To fill with other uses, say pedestrians.
Taxi falls, pedestrians get crushed bellow, but now the vehicular speed isn't 20-30 mph tops, but the terminal velocity of the vehicle.
mv^2 is mean.
flying taxi startups, drone companies, jetpack companies, and all the other fantastical flying startyps keep trying to say they have applications in mountain rescue, but i'm pretty sure that's providing a lot more benefit to the flying taxi startup's pitch deck than it is to any mountain rescue operation.
The things people will do to not build bike paths.
Not that helicopters make any more sense. The city needs some car bans, and yes, bicycles are part of replacing that. But only mass transit will be able to move enough people when there's a foot of slush on the ground.
This is a coastal city at a fairly run-of-the-mill latitude, people build functional bike networks in much worse.
There needs to be an entire wholesale change in both infrastructure and culture to make bike-commuting workable in most extant cities.
Relatively speaking, the infrastructure is the easy part.
I think we'll get to the heat death of the universe before bike-commuting in Houston, Texas would ever be "a thing".
You know we have these things called "helicopters", right?
Are we — as a species — really going to spend until eternity grovelling around on the ground?
If not, then we need personal aircraft.
Other than wait to be on the ground again?
Even birds spend the majority of their times on the ground.
It is not. Wilderness rescues are extremely resource constrained due to the costs involved coupled with the fact that those in need of rescue were fully aware of the risks before they set out. There's a severe limit to how many tax dollars will go towards bailing adults out of situations of their own making. Lowering costs would quite literally save lives.
The earliest cars were replacing the animal muscle power of carriages--a trivially easy feat given that the most primitive steam and combustion engines easily 10x both the raw power, power-to-weight, and power-density of a team of horses.
You can't fly within 500 feet of any person, vehicle, or structure.
At 500 feet, literally any failure of the aircraft means you die about seven seconds later.
* Any failure tends to turn flying things into unguided missiles
* Noise is extremely hard to control -- I did an FAA helicopter discovery lesson, and oof
* Cities tend to have difficult to manage wind currents and hit-or-miss visibility. I was in a skyscraper across from one hit by a helicopter trying and failing to land in 2019 -- there's reasons for city no-fly zones
* Limited landing sites makes them highly situational in the first place, unless you want your streets to be helipads, which you don't
These are all fairly intrinsic and not mitigable. I can think of more issues more in the sticks, but you get the idea.
Imagine being in a flying car. Nope nope nope!
If ground vehicles side-swipe, it's just an insurance claim. If flying vehicles sideswipe, it's a Problem(tm).
That makes me skeptical of all of these (minus the wind currents in cities, that might have taken a little longer).
It is not only not unique, but in fact extremely common for startups to be grifts around impossible technical promises, live a few years off gullible investors who have way more money than sens and/or for whom losing a few million dollars on a long shot is just as bad as me wasting a few dollars on a gizmo off Temu I know probably won't work, and which then die out because their ideas obviously couldn't work.
They even sometimes find a niche by pivoting to some vaguely related tech. Say, while flying taxis obviously won't work, a startup trying to build them might find itself developing into a small company building helicopter propeller blades for some specific niche.
Here's my sanity check when reading something like this on hn: What do you have me believe about the founder/investors? I understand that it's fun and common around here to be arrogant enough to presume that other people are absolute idiots, who are incredibly bad at their jobs, but I am not interested. If all you can bring are "duh" ideas, then that's a red flag.
Unless you can bring really insightful ideas, I am going to err on the side of the people who put years of their time into it and the people who put millions of dollars into it
Are they still going to be wrong? Of course. Am I likely to think the sidechair hn commentator is simply missing something in the bigger picture? Yes (and I can think of multiple concrete things in this case)
I don't know if a silent, fail-safe, and efficient method of flight is physically impossible or not, but I do know this is low on the list of applications it would be first seen in.
EDIT: I'm looking at the air taxi companies this thread started with, and no, they have not solved any of the relevant problems.
Many people are against helicopters on the grounds of noise, safety and pollution. Electric taxis will be welcomed once they are certified and economical. They only need to do better than helicopters.
[0] - https://stopthechopnynj.org/frequently-asked-questions/
Do you believe helicopters are noisy because they're not electric ? Your electric taxi will do the same thing: they need propellers. Propellers that can carry up to 1 ton are fucking loud.
Electric taxis will never be welcomed because they are a dumb idea.