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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]

#141

Post by WhompingWindows »

Mononokay wrote: post #135
Kequc wrote: 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…

They said this was starting in NZ, which is quite different than the US in terms of energy sources.

Yes, New Zealand had 40% renewable energy in 2016, which is 4th in the OECD in terms of energy share [0]. They are also an island, thus they have an incentive to generate their own energy and store it in battery-powered vehicles, rather than importing fossil fuels from afar.

[0]: http://www.mbie.govt.nz/info-services/sectors-industries/ene...

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

#142

Post by CodeWriter23 »

product50 wrote: post #72
Quanttek wrote: post #17

I must say I'm against this development. First of all, even if electric, this is certainly a very inefficient way of transportation that will 'waste' a lot of energy to transport maybe 4 people. The resulting price of this technology will result in the 99% stuck on the ground while the only te 1% can afford the fare. And even if it becomes a regular mode of transportation, do you really want these planes to fly over…

Typical cynical hacker news comment. Have you seen any numbers wrt mileage? Do you know if this will be debuted as a taxi which can transport users vs. something one can own? Have you seen any wrt emissions vs. a normal suv which carries a family of 4? I am amazed how you can come to this conclusion without knowing anything about the product.

I’m amazed you missed the parts where everyone in the video referred to it as an “air taxi”.

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

#143

Post by mrep »

clon wrote: post #24
Quanttek wrote: post #17

I must say I'm against this development. First of all, even if electric, this is certainly a very inefficient way of transportation that will 'waste' a lot of energy to transport maybe 4 people. The resulting price of this technology will result in the 99% stuck on the ground while the only te 1% can afford the fare. And even if it becomes a regular mode of transportation, do you really want these planes to fly over…

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

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

#144

Post by clon »

mrybczyn wrote: post #87
clon wrote: post #19

Earlier quoted context omitted.

I think it being autonomous is integral to it being a "success". Energy density is still a major limitation and doing away with the pilot can be one way to make the numbers work economy wise. A flesh and bone pilot will come at a substantial weight penalty, effectively reducing the utility of this 2 seater by half. As a licenced pilot myself, I am with you, however. Would not climb into this death trap as a self load…

Seeing the rates of "single vehicle accidents" in small aircraft piloted by amateurs, I'm happier with the autonomy. Also, autonomy in the sky seems easier than autonomy on the ground. If Thrun is involved, chances are it will work pretty well...

> Also, autonomy in the sky seems easier than autonomy on the ground.

This is debatable.

A car has only 1 degree of freedom. An aircraft typically has 3 degrees of freedom.

A car rests on solid ground. An aircraft is submerged in a fluid medium.

A ground vehicle can adjust it's speed to the conditions, if necessary slow down if confidence levels get lower, or even go backwards. An aircraft is typically subject to an aerodynamic envelope.

As for the sky being empty, take a look at this harrowing story of a biz jet encountering the wake turbulence of a A380. Airframe written off, crew earn their lifetime salary. Autopilot took 13 seconds to conk out.

https://avherald.com/h?article=4a5e80f3

Turns out modern aircraft following airways to a precision of mere meters has increased such incidences. In the olden days pilots where often a bit off the track. To simulate this sloppiness in flying rigor, a thing called SLOP has been conceived, for Strategic Lateral Offset Procedures.

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

#146

Post by tantalor »

ape4 wrote: post #25
js3dev wrote: post #5

KittyHawk is not an Alphabet startup. It is no affiliated with Alphabet. The title is misleading.

Another article on HN today says it has personal funding from Larry Page. ie not Alphabet.

Source for that: http://www.businessinsider.com/google-cofounder-larry-page-f...

"not clear how much"

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

#147

Post by syntaxing »

BatFastard wrote: post #136
syntaxing wrote: post #118

Earlier quoted context omitted.

I don't get how it is physically possible that this plane is energy efficient? The smaller prop, the less efficient the thrust conversion. You also need laminar air for rear props to be efficient. The drag on the wings should create a ridiculous wake behind the aircraft. I would love to learn how KittyHawk are trying to mitigate these problems (which are huge constraints even for major players).

It is all relative on efficiency IMHO. And since it is electric which can be powered by "clean energy" how do you measure it.

Efficiency is not relative especially when it comes to mechanical movement. It is quantifiable data and nature does not care whether the energy is "green" or "clean". Energy is energy regardless how it is produced. Though the best data they can provide is the lift to drag ratio at cruise speed. This will give us a pretty good idea on how this aircraft performs.

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

#148

Post by danielvf »

willglynn wrote: post #138
ransom1538 wrote: post #70

Small planes have had parachutes for quite some time [1] now and have saved many lives. Why on earth would this company put people up into the air unmanned without one? [Personally, if a parachute was onboard I wouldn't mind jumping into one.] https://www.youtube.com/watch?v=kQyrPVIIQdE

> [Personally, if a parachute was onboard I wouldn't mind jumping into one.] The cabin opens in a clamshell fashion and that appears to be the only way in or out. Opening the canopy mid-flight would probably result in shearing it off once it catches even a small amount of air. From there, you're left with exit point that's ahead of the wing, ahead of the main propeller, and ahead of the rather wide tail section. Mayb…

The Cirrus has a whole aircraft parachute - you can see it used here: https://www.youtube.com/watch?v=J94sGh8fQN8

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

#150

Post by CodeWriter23 »

seanmcdirmid wrote: post #114
Kequc wrote: 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…

> Electricity has to be generated and in the US that's mainly coal. Huh? Coal is only 30% of the USA’s energy production, natural gas is higher at 34%. https://www.eia.gov/energyexplained/index.cfm?page=electrici... The other points in your post are equally dubious, do you have sources?

Are you suggesting natural gas generation is “Green”?
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