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Cora – Kitty Hawk's prototype air taxi [video]

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Re: Cora – Kitty Hawk's prototype air taxi [video]

#181
post #143
post #24

Earlier quoted context omitted.

I agree. People talking about flying cars sound a lot like people demanding faster horses. Or flying horses. I do not think the American dream of a private car scales too well to the future, be it with rubber wheels or tiny propellers. Especially given the population growth. Instead, a brief visit to Singapore, for example, will convince anyone what the future of transportation looks like. A public transport system,…

How safe is Singapore public transportation and walking? The reason I ask is that neither are as safe as driving here in the US which i consider a major blocker in the public transportation utopia people keep dreaming up. Relevant discussion I have had about this topic: https://news.ycombinator.com/item?id=16462803

The reason public transport and walking can be unsafe is the us has deliberate policies making it so. We have more police presence on roads, and less on transport. We have urban design explicitly supporting the car, with human unfriendly design. Look at how many roads have no side walks or bike paths. A 1 mile journey in many areas is unsafe without a car. We need a massive rethink of how we design cities, and there are issues at all levels of government. Federal government tax incentives favor single family detached homes, and Grant money goes towards expanding infrastructure in an unsustainable and unsafe manner.

Re: Cora – Kitty Hawk's prototype air taxi [video]

#182
post #140
post #137

Earlier quoted context omitted.

Yeah that'd be the link it's the first image on the page.

The image/graph you're referencing illustrates "United States total primary energy consumption by fuel in 2015". Total, not electric. You were discussing production of electricity, which is shown in the table I linked on that page to be 32%.

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Re: Cora – Kitty Hawk's prototype air taxi [video]

#183

Earlier quoted context omitted.

> A Cirrus SR22 can go 1,200 miles on 80 gallons of gas. That's roughly speaking 15 miles per gallon - better than many pickup trucks or large SUVs. Sure, let's take the most energy efficient aircraft and compare it to the least energy efficient passenger vehicles??? I mean, how can one even pretend that is a fair comparison. More generally for energy efficiency, it is well known that the most efficient trip is a sho…

We do seem to have different value systems. I believe applying energy to make human lives better is a great thing! Electricity usage in the western world is getting greener fast. Total usage is going down, not up. This isn't going to reverse either of those trends. There's a popular perception that all aircraft burn energy like an oil refinery on fire. The reality is that small piston aircraft are approximately as fu…

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Re: Cora – Kitty Hawk's prototype air taxi [video]

#184
post #140
post #137

Earlier quoted context omitted.

Yeah that'd be the link it's the first image on the page.

The image/graph you're referencing illustrates "United States total primary energy consumption by fuel in 2015". Total, not electric. You were discussing production of electricity, which is shown in the table I linked on that page to be 32%.

Wait, how does that make sense?

What kind of energy if not electrical is coal being used to produce?

Re: Cora – Kitty Hawk's prototype air taxi [video]

#186

A lot of negative comments here. I must say I'm impressed and I applaud these people for building an innovative working thing and taking it to production. No pilot - mind blown. And sure, this might not be the solution to humanity's overall mobility, but heck I can see it being useful in many ways.

Sadly negative comments are the norm here on hacker news. No matter how amazing the news, the top comment is usually a snarky takedown of the linked article.

(It's nice to see the top comment on this one is actually positive!)

Re: Cora – Kitty Hawk's prototype air taxi [video]

#187

Earlier quoted context omitted.

Agree with most of what you say, but two open questions- debt alone on $500k amounts to $180/day (10yr am, 6%). Then there’s cost of energy, dead time during recharge, dead leg trips to the next customer, dead let to charge port, maintenance will be rigorous even if the plane doesn’t need it because FAA. Landing fees while be high for urban landing points, plus ground crew at some locations. “Max $100/hr” is way low,…

Great video on the Pan Am building rooftop helicopter service to NYC area airports. https://www.youtube.com/watch?v=8nbz5VFilxY

This was an awesome video; I had no idea this type of thing ever existed. Thanks for sharing!

Re: Cora – Kitty Hawk's prototype air taxi [video]

#188

Contrary to almost every comment here so far, this is both innovative and energy efficient. Let's talk energy efficiency first. Once it's up in the air, it's has a similar profile to a normal single engine airplane. A Cirrus SR22 can go 1,200 miles on 80 gallons of gas. That's roughly speaking 15 miles per gallon - better than many pickup trucks or large SUVs. And that's while going 180 mph. Slower is more fuel effic…

> On the revenue side, this would replace a two hour trip across a city in traffic with a fifteen minute flight. If a city takes two hours to cross in traffic, that's a clear sign it needs a subway or monorail.

Which both cost billions over billions, and you will not achieve that good connection for the majority of citizens with just one line.

Re: Cora – Kitty Hawk's prototype air taxi [video]

#189
post #107

I don't like that they're touting no emissions. Electricity has to be generated and in the US that's mainly coal. Hybrid vehicles are closer to having it right where running the car charges it and you can get by burning significantly less fuel. Strictly electrical has not been shown to be an energy saver or a flag bearer of emissions reduction. In many cases so far it has been a cause of more pollution than modern en…

An airplane powered by fuel cannot be zero emissions. If you don't make any changes to a 737, it will continue to emit the same amount of CO2 etc. until the end of time, regardless of what happens in the rest of the energy sector.

This vehicle can be zero emissions today, if the power required is generated by wind/solar/hydro/etc. Sure, with today's grid's it won't necessarily be ZE, but it can be, and as time progresses and grids get updated with more and more renewable energy, it's effective emissions will continue to go down, with no changes needing to be made to the vehicle itself.

That's important.

Re: Cora – Kitty Hawk's prototype air taxi [video]

#190

I just gave a talk on flying cars. It turns out technical difficulty is not the reason we don't have flying cars, or self-driving cars. Innovation is one way new technologies can change the world. For example, the reason we have skyscrapers is due to the elevator brake. Elevators have existed in some form or another for over 2,000 years. But without the modern innovation of the elevator brake, nobody felt safe being…

What unless ? This is fun. I understand most of the engineering is in regression, but still making things that fly is fun. Only problem is money.
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