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Regional Air Mobility: Why we don’t plan to operate flights under 20km

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Re: Regional Air Mobility: Why we don’t plan to operate flights under 20km

#241

Post by [deleted] »

giarc wrote: post #82
hristov wrote: post #36

Earlier quoted context omitted.

Until you invent anti-gravity, VTOL will always be (i) very energy intensive, and (ii) and very disruptive to the surrounding environment. This is both in terms of noise and air turbulence. Self driving is something that may be solved and can become practical for popular use with current and near-term foreseeable technology. Everyday mass use VTOL is not. Sorry, the Jetsons lied to you.

>Everyday mass use VTOL is not. Sorry, the Jetsons lied to you. Many companies are working on this problem currently. I would say consumer accessible, piloted electric VTOL is closer than fully self driving vehicles.

[deleted]

Re: Regional Air Mobility: Why we don’t plan to operate flights under 20km

#242

Post by bobthepanda »

trynewideas wrote: post #235
bobthepanda wrote: post #139

Earlier quoted context omitted.

Lots of things are in fairly close proximity to highways, this is not really a solution. Crashing into the tower block next to a highway is still pretty bad. Lots of things in dense areas also are not necessarily on an easy route near a highway, so if that's the limitation you run into Concorde's old problem of "where can you actually fly this thing?"

I'm skeptical about the rest of it, but the article lightly covers using existing transport corridors (waterways, rail tracks, and to a lesser priority arterial roadways) as routes for these medium-range flights that explicitly avoid populated areas.

My issue with this is that most transport corridors are

1. not very wide in the first place. Any air vehicle could cross the width of your standard rail line or highway or river in seconds.

2. Surrounded by intensive land uses, because the transportation corridor itself provides valuable access. So vehicles don't have to go very far off the right of way to crash into something valuable where lots of people are.

Re: Regional Air Mobility: Why we don’t plan to operate flights under 20km

#243

Post by steffan »

hristov wrote: post #36
giarc wrote: post #4

I can't remember who said it or on which podcast, but they basically said that VTOL is the real game changer, not autonomous driving. Sure autonomous driving might be able to shave some time off of your commute, but you are still in a car and still driving on roads. VTOL is what really allows you to experience what the ultra wealthy with access to private jets and helicopters have experienced. Getting out of the city…

Until you invent anti-gravity, VTOL will always be (i) very energy intensive, and (ii) and very disruptive to the surrounding environment. This is both in terms of noise and air turbulence. Self driving is something that may be solved and can become practical for popular use with current and near-term foreseeable technology. Everyday mass use VTOL is not. Sorry, the Jetsons lied to you.

> Sorry, the Jetsons lied to you

No kidding. They promised Rosie and we got Roomba.

Re: Regional Air Mobility: Why we don’t plan to operate flights under 20km

#244

Post by steffan »

missedthecue wrote: post #164
mangecoeur wrote: post #51

Can an American please explain how a 3h41 minute car journey to Tahoe turns into an 8h49(!) train journey? Are your trains pulled by horses or something?

Amtraks stop for 20 minutes every 30 minutes to let passengers on and off at each stop. A car journey only stops if you need gas (15 minutes) or if you need to use personal facilities (10 minutes). Furthermore, an amtrak will only hit a top speed of 79mph, and only a few times during the journey, while a car can stay at 75mph for most the journey.

> while a car can stay at 75mph for most the journey.

You've never driven to Tahoe on a holiday weekend, I see

Re: Regional Air Mobility: Why we don’t plan to operate flights under 20km

#245

Post by manquer »

s1dev wrote: post #239
dreamcompiler wrote: post #205

Earlier quoted context omitted.

Lots of innovation has happened in aircraft electronics. The powerplant? Not so much. Most light aircraft engine designs are four or more decades old, and the only ones cheap enough for a moderately-priced aircraft have carburetors. I don't think you can even buy a car these days with a carburetor, but with airplanes they're still standard, even though fuel injection makes a lot more sense in an airplane than in a ca…

The problem with the 100LL phase-out is that you have over 70 years of engines and fuel systems designed to work with leaded fuel. In order to complete the phase-out you either need to: force people to put a new $30K+ engine into a The FAA has been attempting the second route for some years, but to date has not been terribly successful. The first route has been done successfully in other regions such as the EU, but I…

You have a sensible third option which is how automotive changed for the most part.

Grandfather in current planes and mandate new models to use new fuel only. Over time, perhaps lot longer than cars(planes do have longer life) you will have changed all of them.

Had they started it in 80's and 90's same time as auto-mobiles, most planes would have changed by now.

Every industry faces the same challenges to transform technology, they are able to move forward without as much difficulty as aviation ?

Re: Regional Air Mobility: Why we don’t plan to operate flights under 20km

#246

Post by danaliv »

jessriedel wrote: post #203
aphextron wrote: post #194

Earlier quoted context omitted.

Aviation regulations are written in blood. They are the only reason you can step into an aircraft with a reasonable expectation of making it safely to your destination. Disasters are generally not caused by obvious large issues, but a multitude of smaller compounding, seemingly benign causes that could otherwise be easily dismissed. The massive body of regulation around aviation is a direct result of this. Each one i…

That regulations are motivated by avoiding deaths does not mean that they are effective at that, or even if they are effective that they are worth the costs. Regulations that specify specific safety equipment, rather than specifying target error rates or bonds/liability, are the worst because they get enacted and then stay on the books for decades unchanged.

They aren’t motivated by it. They’re a result of it. Practically every rule or standard in the book can be traced to a crash. Mode C veil? Aeromexico 498, 82 dead. Radio comms standardization? Tenerife, 583 dead. CRM: United 173, 10 dead. Altitude requirements while being vectored to an approach (91.175(i)): TWA 514, 92 dead.

I could go on.

The answer to “why can’t we just” in aviation is “because people died.” The FAA doesn’t make rules just to make them. They make them because aviation is unforgiving and it will kill you and your passengers if you screw it up.

Re: Regional Air Mobility: Why we don’t plan to operate flights under 20km

#248

Post by danaliv »

stickfigure wrote: post #209
aphextron wrote: post #194

Earlier quoted context omitted.

Aviation regulations are written in blood. They are the only reason you can step into an aircraft with a reasonable expectation of making it safely to your destination. Disasters are generally not caused by obvious large issues, but a multitude of smaller compounding, seemingly benign causes that could otherwise be easily dismissed. The massive body of regulation around aviation is a direct result of this. Each one i…

> Each one is almost always a direct response to a particular incident that killed people ...in 1970. Not saying that all aviation regulations are bad, but the fact that carburetors are still used in general aviation is pretty damning.

Nothing damning about it. It works.

I know seven people who have experienced engine failures in general aviation airplanes. Not one had anything to do with the carburetor.

Re: Regional Air Mobility: Why we don’t plan to operate flights under 20km

#249

Post by deepnotderp »

runarberg wrote: post #225
deepnotderp wrote: post #220

Earlier quoted context omitted.

Access to transportation is a stronger predictor of economic mobility than growing up in a two parent household, early test scores or the crime rate. So yes, it is in fact, extremely socially beneficial.

Note that in many cases access is not only restricted by availability, but also affordability.

Time of commute is also a major factor.

Re: Regional Air Mobility: Why we don’t plan to operate flights under 20km

#250

Post by [deleted] »

dzhiurgis wrote: post #240
runarberg wrote: post #222

Earlier quoted context omitted.

> The rich 'subsidize' progress for everyone This sounds like an HN version of trickle down theory which I thought had been thoroughly debunked by economists. It’s funny but, I’ve always been under the impression that the opposite were true in standard economics, the poor—with their labour—are the once who subsidize the rich. I find it hard to believe that the economics of progress are any different. Let me draw up s…

Sir, this is not reddit.

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