Larry Page’s startups working on flying cars • Hacker News Board

Re: Larry Page’s startups working on flying cars

#71

Post by Gravityloss » Thu, Jun 09, 2016, 2:43 PM UTC

jackhack wrote: post #58

Nokinside wrote: post #21

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 infra…

>>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-p…

IMO fenestron equipped helicopters are significantly more pleasant to listen to. There's no sharp slapping from the tail rotor.

Re: Larry Page’s startups working on flying cars

#72

Post by adwf » Thu, Jun 09, 2016, 2:46 PM UTC

knodi123 wrote: post #65

adwf wrote: post #52

Earlier quoted context omitted.

Not necessarily. If a car is twice as efficient, but has to travel three times as far because of the windy road system, the flying car will have it beat in a straight line.

> travel three times as far because of the windy road system, Ironic choice of words. The winding road system adds distance to your commute, but a windy airspace adds air-miles to your commute. That is, a flying car doesn't travel through the same amount of air when going 1 ground mile in different directions.

Haha, completely unintentional. Very good point though.

Personally I don't think flying cars will take off (ha, done it again...) for quite some time, if only for risk reasons. Think about just how many car accidents there are every day, now imagine every accident ending with a 100m death plunge from the sky. I just can't see it going mainstream for a long time.

Re: Larry Page’s startups working on flying cars

#73

Post by drzaiusapelord » Thu, Jun 09, 2016, 2:48 PM UTC

Nav_Panel wrote: post #62

drzaiusapelord wrote: post #46

Earlier quoted context omitted.

This doesn't solve the parking problem. Sure, you get to work a bit faster but now you need to put that thing down. In a downtown area where there's a major price premium for parking. Getting to work in 10 minutes instead of 30 is going to be attractive and that'll raise parking demand, but there's only going to be so much parking available. Tearing down profitable office buildings to make flying car parking lots wil…

> This doesn't solve the parking problem. Sure, you get to work a bit faster but now you need to put that thing down. In a downtown area where there's a major price premium for parking. What I envision instead is an extension of the office park concept, but suddenly there's no traffic congestion. You could have massive suburban/exurban growth and still have incredibly short commutes -- employees fly to their offices…

Except its the dense urban areas with the serious traffic and the kinds of people with the disposable income to consider a $300,000 vehicle who are probably going to be the main buyers here.

I think suburban people probably aren't as motivated and if this stuff can't handle skyscrapers then the concept is pretty much dead outside of recreational usage.

Re: Larry Page’s startups working on flying cars

#74

Post by dekhn » Thu, Jun 09, 2016, 2:50 PM UTC

adwf wrote: post #52

dekhn wrote: post #41

Earlier quoted context omitted.

The efficiency argument doesn't work: moving up against gravity will always be more expensive.

Not necessarily. If a car is twice as efficient, but has to travel three times as far because of the windy road system, the flying car will have it beat in a straight line.

I think you'll need to adjust that from "three times", to "90 times" for the physics and math to work.

Re: Larry Page’s startups working on flying cars

#75

Post by 6stringmerc » Thu, Jun 09, 2016, 2:54 PM UTC

skykooler wrote: post #64

Kind of odd how, with all the little schematics of flying cars on that page, Terrafugia is nowhere to be found.

Their new design, the TF-X, is the first schematic...

Re: Larry Page’s startups working on flying cars

#76

Post by sievebrain » Thu, Jun 09, 2016, 2:54 PM UTC

Nokinside wrote: post #33

sievebrain wrote: post #28

Earlier quoted context omitted.

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?

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.

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.

Re: Larry Page’s startups working on flying cars

#77

Post by 6stringmerc » Thu, Jun 09, 2016, 2:55 PM UTC

joakleaf wrote: post #13

Related is this one-man drone by a Chinese company which should being test flights in Nevada: http://www.ehang.com/news/146.html "Drone" because the on board computer handles all the flying (just pick a destination).

And hopefully one that won't have any issue with 8 rotating blades coming into contact with wildlife or squishy humans.

Re: Larry Page’s startups working on flying cars

#78

Post by dekhn » Thu, Jun 09, 2016, 3:06 PM UTC

jonnycowboy wrote: post #45

dekhn wrote: post #41

Earlier quoted context omitted.

The efficiency argument doesn't work: moving up against gravity will always be more expensive.

There are always tradeoffs... airplanes move more or less at a steady speed, and are much more aerodynamic than cars, which spent quite a bit of time stuck in traffic. Thus in many cases planes are more efficient than cars (despite needing to lift).

Airplanes have to go faster than the stall speed. Stall speed is typically ~60mph or more, and air resistance goes up as the square of the speed (times the aerodynamc cross section). Airplanes aren't really that much more aerodynamic than modern cars.

Re: Larry Page’s startups working on flying cars

#79

Post by JDDunn9 » Thu, Jun 09, 2016, 3:11 PM UTC

I just emailed the people at Moller this week asking them what the biggest challenge in making a flying car was. Their reply was:

Thanks for reaching out to Moller International. Your question is a good one, with a multitude of answers. For now, I’ll explain 3 of the biggest factors. First, there is a lot of FAA and government regulations regarding aircraft. Airworthiness certification is a lengthy process, and depending on the level at which a company wishes to test, operate, and potential sell their aircraft, the process can take anywhere from a few months to a few years. Second, as stated previously, time is a major factor not only for development, but also testing, marketing, etc. In aviation, there are no “unimportant” parts at 10,000 ft. Safety is always a top priority throughout the entire process. Third, and finally, funding. Companies like Moller International depend greatly on their investors and supporters to keep the lights on. Until there is a product being sold, and cash being brought in regularly, a company must depend on some other source of funding. Aircraft programs are not known to be easy and cheap; these programs are some of the more expensive ones out there, especially in the private sector. With all of this said, all of us here at Moller International are working hard to ensure the latter two have as minimal an impact as possible. We have been working in cooperation with the FAA to get things going as quickly and safely as possible. Let me know if you have any other questions.

Re: Larry Page’s startups working on flying cars

#80

Post by marssaxman » Thu, Jun 09, 2016, 3:12 PM UTC

Nav_Panel wrote: post #62

drzaiusapelord wrote: post #46

Earlier quoted context omitted.

This doesn't solve the parking problem. Sure, you get to work a bit faster but now you need to put that thing down. In a downtown area where there's a major price premium for parking. Getting to work in 10 minutes instead of 30 is going to be attractive and that'll raise parking demand, but there's only going to be so much parking available. Tearing down profitable office buildings to make flying car parking lots wil…

> This doesn't solve the parking problem. Sure, you get to work a bit faster but now you need to put that thing down. In a downtown area where there's a major price premium for parking. What I envision instead is an extension of the office park concept, but suddenly there's no traffic congestion. You could have massive suburban/exurban growth and still have incredibly short commutes -- employees fly to their offices…

Wait, now - you want to exacerbate sprawl and worsen suburban inefficiency, and this is supposed to be a benefit? I think you have just convinced me that personal flying vehicles are a terrible idea to be opposed at all costs.