10 ms·

Helicopters and small planes already exist. We might have autonomous helicopters and small planes in the future, but flying car concept is flawed and not beca

Helicopters and small planes already exist. We might have autonomous helicopters and small planes in the future, but flying car concept is flawed and not because it's hard to build one. - Preflight checks and flight safety. Larry should first build normal small aircraft that can do without constant manual checks before flight. This is actually good subgoal to work with even without flying cars in mind. Reliable infrastructure that checks and calibrates instruments so reliably that you don't need manual checks would be revolution in aerospace. Just walking from your car into your future Cessna-Android and flying off would be sci-fi for aviators. - Energy consumption. No matter how energy efficient the engines are, hovering and short takeoffs use lots of energy. Flying with small wings with little lift is equivalent to driving monster trucks in full power. You don't want flying becoming everyday phenomenon until we have abundance of carbon free energy. - Noise and safety regulations, aviation regulations over urban areas. Flying cars are not happening in the suburbs or anyone where lots of people live. In the meantime try to get new helicopter landing sites approved in your neighborhood. If you have to take car to your flying car hangar, just have a small plane instead. Or walk to a buss station.

sievebrain 10y ago
Your first point makes sense, but if the flying cars are fully electric then I'm not sure how much of the work to make existing small aircraft totally reliable would be applicable to such a different machine. I guess that leads on to the question of, why not start by making an electric self-maintaining self-flying Cessna?
- Nokinside 10y ago
  Energy density of jet fuel and gasoline is something like 45-46 MJ/kg. All rechargeable lithium-whatever batteries have less than MJ/kg. Turboprops are efficient and reliable. They have good power-to-weight ratio. Currently electric motors are good only for things like gliders that need relatively little power.
  - prplhaz4 10y ago
    This link (recently on HN) provides an interesting analysis of the options: http://spectrum.ieee.org/aerospace/aviation/how-i-designed-a-practical-electric-plane-for-nasa http://spectrum.ieee.org/aerospace/aviation/how-i-designed-a... It seems like a fuel cell could be a viable option in the not-too-distant future, but still comes with a good number of trade-offs...
  - jp555 10y ago
    If self-flying taxi average flight times are 15 min, does this matter?
    - jacquesm 10y ago
      It does if you want to operate your self-flying taxi in an economically sound manner. All the time that it is on the ground it is not making money. Which means you'll be charging it when the number of requested rides is low, so you'll need to make a number (possibly quite a large number) of 15 minute rides before you get to recharge.
      - gohrt 10y ago
        15 minute flight, 15 minute back to depot, 5 minute battery swap, charge batteries at the depot.
  - sievebrain 10y ago
    Yes, I know, jet fuel is one of the most energy dense things out there. But the article talks endlessly about electric power being the key to a self flying car, so I assumed the whole discussion was contingent on that being practical.
  - lettergram 10y ago
    Blimps would also be viable. You can significantly reduce the required energy to get them to move
    - 10y ago
jackhack 10y ago
>>In the meantime try to get new helicopter landing sites approved in your neighborhood. Which takes us right back to the noise issue which needs to be solved, first. 'Till then, no way. Helicopters (nicknamed 'choppers' for good reason) buzzing over neighborhoods aren't exactly the average homeowner's dream. The "whapwhapwhapwhap" of a helicopter overhead, reverberating through a home, is just as desirable as open-pipe Harley Davidson motorbikes or roaring hotrods. That is to say, it's not. Other than a crash, I can't think of a surer way to put people off from air traffic than noise. (edit: grammatical typo: than->as)
- Gravityloss 10y ago
  IMO fenestron equipped helicopters are significantly more pleasant to listen to. There's no sharp slapping from the tail rotor.
- JDDunn9 10y ago
  I don't think cities have the ability to regulate helicopters. Airspace is regulated by the FAA, which pre-empts the states from regulating them further. I remember reading an article about some city where helicopter noise had become a problem and they couldn't do much about it. Although I suppose with enough complaints the FAA might change their rules.
  - arebop 10y ago
    Surely they can regulate use of land. What good is your helicopter without a helipad?
  - nsxwolf 10y ago
    Increase the amount of helicopter-style traffic by 10x, and eventually congress will make the FAA enact new regulations.
  - run4yourlives2 10y ago
    Airspace is regulated federally in most countries, but what you can build on the ground is almost always local in regulation. You might be allowed to fly overhead without he city being able to do much about it, but you won't be able to land or take off. (And to be honest, if the city complains to the federal regulators regarding noise, they almost always listen - almost every airport in a town has strict noise-reducing approach patterns for this reason already.)
kordless 10y ago
The primary problem with flying things is that they currently rely on atmospheric lift. Loss of lift equals death of occupants and vehicle. It's only when we transition to alternate means of lift that flying will be "safe" for public consumption and operation.
- cpncrunch 10y ago
  There are safety measures such as autorotation and airframe parachutes that can safely land the aircraft after an engine failure.
  - alphapapa 10y ago
    And what happens when a Cessna parachutes onto the roof of your house? Onto the middle of a busy street? etc. If we were all using flying cars, this would become a regular occurrence. It's just not practical at that scale.
    - skj 10y ago
      What happens when a car veers off the road into your living room?
      - PhasmaFelis 10y ago
        The basic design of roads and their surroundings mean that an out-of-control car is relatively unlikely to collide with a building, as opposed to another car, a utility pole, a divider/barrier, etc. Conversely, an aircraft falling over a built-up area is very likely to encounter a building, and even if it lands in a road, it's going to be harder for moving cars to spot and avoid than an out-of-control car would be.
      - TeMPOraL 10y ago
        Probably much less damage, because a typical car in the city is going much slower than a typical plane falling from the sky, and kinetic energy goes with square of velocity...
Shivetya 10y ago
So lets get silly here; granted I wanted a flying car ever since seeing a Spinner in Blade Runner. Deploy a balloon above the vehicle when not under power which reuses the helium when not moving beyond a set speed. Pretty sure it can be an airfoil in itself and compact enough to sit above the craft. When transitioning to full on flight it can be partially deflated to reduce its air resistance but still retain the shape needed for lift. Plus why do these air cars need such high speeds when flying? Since I am not a wiz at these things I am not sure how much balloon you need to compensate sufficiently for the vehicle weight. You don't need to compensate all of it, just enough so that when all power fails you don't hit the ground beyond the means of the occupants to survive. With modern electronics losing power at altitude should allow a glide landing.
- gambiting 10y ago
  To "reuse" the helium it would need to compress it again - and that uses a lot of energy. Not to mention that you would need a lot of helium, and helium, almost like hydrogen, has a tendency to escape from its containers so you need really heavy lead bottles to store even a few litres. It's not impossible, but it does not seem practical in any way.
  - nradov 10y ago
    Helium is typically stored in steel or aluminum pressure vessels. Not lead. Lead is heavier and more expensive, and it's soft enough that attaching valves can be problematic.
outworlder 10y ago
> Preflight checks and flight safety. Larry should first build normal small aircraft that can do without constant manual checks before flight. Omg, this. The amount of checks required for any sort of aircraft is ridiculous. A lot of it involves button pushing and checking status. This could be automated. For instance, for a cessna 150: STARTING ENGINE Mixture – RICH Carb heat – COLD Prime – AS REQUIRED Master switch -- ON Beacon Light – ON Throttle – OPEN 1/8” Prop Area – CLEAR Ignition – START Oil Pressure – CHK Radio – ON/SET Transponder – ON / STBY Wing Flaps – UP Mixture – LEAN 1 INCH READY TO TAXI Most of these things could be set automatically.
- cpncrunch 10y ago
  With modern FADEC engines, all of this is automated (from what I read...I've never actually flown anything with FADEC).
  - jeiting 10y ago
    The recent diesel installs with FADEC that Redbird has been doing in 172s have a one button run up: You just hold the breaks and hit a button and the FADEC does the run up and checks all parameters and gives you a go/no-go. FADEC - Full Authority Digital Engine Control
    - Natsu 10y ago
      And here I thought it was 'Automatic', but I haven't dealt with a FADEC since I wrote avionics test scripts almost 20 years ago.
    - rorosaurus 10y ago
      Very interesting. Do you know how this system handles eventual sensor failure?
- handedness 10y ago
  The examples you gave take no more than 30 seconds. Sure, FADEC can eliminate most of them, but they're quick. Other examples–checking the oil, the tank sumps, the intake, the tires, the flap tracks, the rudder bolt(s), the wing tips, the tailwheel springs, etc.–are the stuff that software largely can't replace, and are the more time-consuming part of taking off. Put another way, the latest fighter jets and commercial heavies still have significant visual preflights.
narrator 10y ago
You forgot the big one: Most small aircraft cannot fly in bad weather. If it's raining, windy, or even cloudy these things are going to be grounded if the pilot doesn't have an instrument rating.
- rileyteige 10y ago
  Not to mention icing conditions!
  - SpikeDad 10y ago
    Not to mention how little skill that a big percentage of people have just driving cars. Can't even get people to follow the speed limit - fat chance you'd get them to follow aviation regulations. Most people in cars that make mistakes end up in a crash but don't die. Everyone in a portable flying device that makes a mistake will die.
- the_watcher 10y ago
  Sure, but that's not a reason to just punt on trying to build a flying car. Larry Page has the money to invest both in stuff he thinks will change the world (which he does both independently and at Alphabet) as well as in things he just wants to exist.
- mtgx 10y ago
  They can be automatically disabled for when there's bad weather.
  - nibnib 10y ago
    That rules out selling any in large parts of the world then.
  - SpikeDad 10y ago
    Hahaha. The function of my flying car is controlled by - Meteorology? Now that's funny. I have respect for meteorologist (heck - for me it was either that or computer science) but even today local forecasting is not reliable enough to base the functionality of devices upon.
ams6110 10y ago
Flying cars, of course, are ridiculous. Best sentence in the article.
Natsu 10y ago
They could do some kind of drone and do all the safety checks regularly before dispatching them, perhaps. Then the people doing the checks only need to be at the site. Maybe also allow remote control that can take over in emergencies and keep a few pilots around for that. That said, convenient landing spots may not exist for many trips, so I have no idea what a good use case would be for this kind of thing.
the_watcher 10y ago
> Noise and safety regulations, aviation regulations over urban areas. Did you read the entire article? An entire section was devoted to how the rise of electric engines addresses the noise issue, as well as some of the safety issues by removing the bomb (internal combustion engine) from the vehicle.
stcredzero 10y ago
No matter how energy efficient the engines are, hovering and short takeoffs use lots of energy. What about electric vehicles with beamed power? The "heavy lifting" for a small electric aircraft could be done at the airport using beamed power, freeing up weight and increasing the effective range of the aircraft.
- TeMPOraL 10y ago
  The question is, how much power would be needed. It screams "military-grade futuristic microwave weapon" to me.
  - stcredzero 10y ago
    LASER!
    - TeMPOraL 10y ago
      Probably even worse / more dangerous.
      - stcredzero 10y ago
        But it sounds cooler!
- tempestn 10y ago
  Rather than beamed power, how about some sort of ground vehicle that launches the aircraft (or pushes it up to a given speed and then releases)?
  - stcredzero 10y ago
    The ground footprint for VTOL vehicles using beamed power is a lot smaller. Even a vertical accelerator built up the side of a skyscraper would have a larger footprint and higher costs.
ohazi 10y ago
> into your future Cessna-Android and flying off Dear god, please don't let Android anywhere near my airplane instruments and flight controls. It's like the exact opposite of a real-time system - practically guaranteed to hang and crash.

sievebrain 10y ago

Your first point makes sense, but if the flying cars are fully electric then I'm not sure how much of the work to make existing small aircraft totally reliable would be applicable to such a different machine. I guess that leads on to the question of, why not start by making an electric self-maintaining self-flying Cessna?

Nokinside 10y ago
Energy density of jet fuel and gasoline is something like 45-46 MJ/kg. All rechargeable lithium-whatever batteries have less than MJ/kg. Turboprops are efficient and reliable. They have good power-to-weight ratio. Currently electric motors are good only for things like gliders that need relatively little power.
- prplhaz4 10y ago
  This link (recently on HN) provides an interesting analysis of the options: http://spectrum.ieee.org/aerospace/aviation/how-i-designed-a-practical-electric-plane-for-nasa http://spectrum.ieee.org/aerospace/aviation/how-i-designed-a... It seems like a fuel cell could be a viable option in the not-too-distant future, but still comes with a good number of trade-offs...
- jp555 10y ago
  If self-flying taxi average flight times are 15 min, does this matter?
  - jacquesm 10y ago
    It does if you want to operate your self-flying taxi in an economically sound manner. All the time that it is on the ground it is not making money. Which means you'll be charging it when the number of requested rides is low, so you'll need to make a number (possibly quite a large number) of 15 minute rides before you get to recharge.
    - gohrt 10y ago
      15 minute flight, 15 minute back to depot, 5 minute battery swap, charge batteries at the depot.
- sievebrain 10y ago
  Yes, I know, jet fuel is one of the most energy dense things out there. But the article talks endlessly about electric power being the key to a self flying car, so I assumed the whole discussion was contingent on that being practical.
- lettergram 10y ago
  Blimps would also be viable. You can significantly reduce the required energy to get them to move
  - 10y ago

jackhack 10y ago

>>In the meantime try to get new helicopter landing sites approved in your neighborhood. Which takes us right back to the noise issue which needs to be solved, first. 'Till then, no way. Helicopters (nicknamed 'choppers' for good reason) buzzing over neighborhoods aren't exactly the average homeowner's dream. The "whapwhapwhapwhap" of a helicopter overhead, reverberating through a home, is just as desirable as open-pipe Harley Davidson motorbikes or roaring hotrods. That is to say, it's not. Other than a crash, I can't think of a surer way to put people off from air traffic than noise. (edit: grammatical typo: than->as)

Gravityloss 10y ago
IMO fenestron equipped helicopters are significantly more pleasant to listen to. There's no sharp slapping from the tail rotor.
JDDunn9 10y ago
I don't think cities have the ability to regulate helicopters. Airspace is regulated by the FAA, which pre-empts the states from regulating them further. I remember reading an article about some city where helicopter noise had become a problem and they couldn't do much about it. Although I suppose with enough complaints the FAA might change their rules.
- arebop 10y ago
  Surely they can regulate use of land. What good is your helicopter without a helipad?
- nsxwolf 10y ago
  Increase the amount of helicopter-style traffic by 10x, and eventually congress will make the FAA enact new regulations.
- run4yourlives2 10y ago
  Airspace is regulated federally in most countries, but what you can build on the ground is almost always local in regulation. You might be allowed to fly overhead without he city being able to do much about it, but you won't be able to land or take off. (And to be honest, if the city complains to the federal regulators regarding noise, they almost always listen - almost every airport in a town has strict noise-reducing approach patterns for this reason already.)

kordless 10y ago

The primary problem with flying things is that they currently rely on atmospheric lift. Loss of lift equals death of occupants and vehicle. It's only when we transition to alternate means of lift that flying will be "safe" for public consumption and operation.

cpncrunch 10y ago
There are safety measures such as autorotation and airframe parachutes that can safely land the aircraft after an engine failure.
- alphapapa 10y ago
  And what happens when a Cessna parachutes onto the roof of your house? Onto the middle of a busy street? etc. If we were all using flying cars, this would become a regular occurrence. It's just not practical at that scale.
  - skj 10y ago
    What happens when a car veers off the road into your living room?
    - PhasmaFelis 10y ago
      The basic design of roads and their surroundings mean that an out-of-control car is relatively unlikely to collide with a building, as opposed to another car, a utility pole, a divider/barrier, etc. Conversely, an aircraft falling over a built-up area is very likely to encounter a building, and even if it lands in a road, it's going to be harder for moving cars to spot and avoid than an out-of-control car would be.
    - TeMPOraL 10y ago
      Probably much less damage, because a typical car in the city is going much slower than a typical plane falling from the sky, and kinetic energy goes with square of velocity...

Shivetya 10y ago

So lets get silly here; granted I wanted a flying car ever since seeing a Spinner in Blade Runner. Deploy a balloon above the vehicle when not under power which reuses the helium when not moving beyond a set speed. Pretty sure it can be an airfoil in itself and compact enough to sit above the craft. When transitioning to full on flight it can be partially deflated to reduce its air resistance but still retain the shape needed for lift. Plus why do these air cars need such high speeds when flying? Since I am not a wiz at these things I am not sure how much balloon you need to compensate sufficiently for the vehicle weight. You don't need to compensate all of it, just enough so that when all power fails you don't hit the ground beyond the means of the occupants to survive. With modern electronics losing power at altitude should allow a glide landing.

gambiting 10y ago
To "reuse" the helium it would need to compress it again - and that uses a lot of energy. Not to mention that you would need a lot of helium, and helium, almost like hydrogen, has a tendency to escape from its containers so you need really heavy lead bottles to store even a few litres. It's not impossible, but it does not seem practical in any way.
- nradov 10y ago
  Helium is typically stored in steel or aluminum pressure vessels. Not lead. Lead is heavier and more expensive, and it's soft enough that attaching valves can be problematic.

outworlder 10y ago

> Preflight checks and flight safety. Larry should first build normal small aircraft that can do without constant manual checks before flight. Omg, this. The amount of checks required for any sort of aircraft is ridiculous. A lot of it involves button pushing and checking status. This could be automated. For instance, for a cessna 150: STARTING ENGINE Mixture – RICH Carb heat – COLD Prime – AS REQUIRED Master switch -- ON Beacon Light – ON Throttle – OPEN 1/8” Prop Area – CLEAR Ignition – START Oil Pressure – CHK Radio – ON/SET Transponder – ON / STBY Wing Flaps – UP Mixture – LEAN 1 INCH READY TO TAXI Most of these things could be set automatically.

cpncrunch 10y ago
With modern FADEC engines, all of this is automated (from what I read...I've never actually flown anything with FADEC).
- jeiting 10y ago
  The recent diesel installs with FADEC that Redbird has been doing in 172s have a one button run up: You just hold the breaks and hit a button and the FADEC does the run up and checks all parameters and gives you a go/no-go. FADEC - Full Authority Digital Engine Control
  - Natsu 10y ago
    And here I thought it was 'Automatic', but I haven't dealt with a FADEC since I wrote avionics test scripts almost 20 years ago.
  - rorosaurus 10y ago
    Very interesting. Do you know how this system handles eventual sensor failure?
handedness 10y ago
The examples you gave take no more than 30 seconds. Sure, FADEC can eliminate most of them, but they're quick. Other examples–checking the oil, the tank sumps, the intake, the tires, the flap tracks, the rudder bolt(s), the wing tips, the tailwheel springs, etc.–are the stuff that software largely can't replace, and are the more time-consuming part of taking off. Put another way, the latest fighter jets and commercial heavies still have significant visual preflights.

narrator 10y ago

You forgot the big one: Most small aircraft cannot fly in bad weather. If it's raining, windy, or even cloudy these things are going to be grounded if the pilot doesn't have an instrument rating.

rileyteige 10y ago
Not to mention icing conditions!
- SpikeDad 10y ago
  Not to mention how little skill that a big percentage of people have just driving cars. Can't even get people to follow the speed limit - fat chance you'd get them to follow aviation regulations. Most people in cars that make mistakes end up in a crash but don't die. Everyone in a portable flying device that makes a mistake will die.
the_watcher 10y ago
Sure, but that's not a reason to just punt on trying to build a flying car. Larry Page has the money to invest both in stuff he thinks will change the world (which he does both independently and at Alphabet) as well as in things he just wants to exist.
mtgx 10y ago
They can be automatically disabled for when there's bad weather.
- nibnib 10y ago
  That rules out selling any in large parts of the world then.
- SpikeDad 10y ago
  Hahaha. The function of my flying car is controlled by - Meteorology? Now that's funny. I have respect for meteorologist (heck - for me it was either that or computer science) but even today local forecasting is not reliable enough to base the functionality of devices upon.

ams6110 10y ago

Flying cars, of course, are ridiculous. Best sentence in the article.

Natsu 10y ago

They could do some kind of drone and do all the safety checks regularly before dispatching them, perhaps. Then the people doing the checks only need to be at the site. Maybe also allow remote control that can take over in emergencies and keep a few pilots around for that. That said, convenient landing spots may not exist for many trips, so I have no idea what a good use case would be for this kind of thing.

the_watcher 10y ago

> Noise and safety regulations, aviation regulations over urban areas. Did you read the entire article? An entire section was devoted to how the rise of electric engines addresses the noise issue, as well as some of the safety issues by removing the bomb (internal combustion engine) from the vehicle.

stcredzero 10y ago

No matter how energy efficient the engines are, hovering and short takeoffs use lots of energy. What about electric vehicles with beamed power? The "heavy lifting" for a small electric aircraft could be done at the airport using beamed power, freeing up weight and increasing the effective range of the aircraft.

TeMPOraL 10y ago
The question is, how much power would be needed. It screams "military-grade futuristic microwave weapon" to me.
- stcredzero 10y ago
  LASER!
  - TeMPOraL 10y ago
    Probably even worse / more dangerous.
    - stcredzero 10y ago
      But it sounds cooler!
tempestn 10y ago
Rather than beamed power, how about some sort of ground vehicle that launches the aircraft (or pushes it up to a given speed and then releases)?
- stcredzero 10y ago
  The ground footprint for VTOL vehicles using beamed power is a lot smaller. Even a vertical accelerator built up the side of a skyscraper would have a larger footprint and higher costs.

ohazi 10y ago

> into your future Cessna-Android and flying off Dear god, please don't let Android anywhere near my airplane instruments and flight controls. It's like the exact opposite of a real-time system - practically guaranteed to hang and crash.