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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

#251

Post by TylerE »

manquer wrote: post #245
s1dev wrote: post #239

Earlier quoted context omitted.

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 t…

No they wouldn't.

You're underestimating the age of the fleet.

The average GA aircraft is 50 years old, and that is likely to increase in the near-medium term as production of GA aircraft is practically zero.

Source: https://www.ainonline.com/aviation-news/business-aviation/20....

(Cirrus, mentioned above, produces about 300 aircraft a year - compare to the 100,000+ Ceessnas on GA fields, almost all of which are over 40 years old.

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

#252

Post by giosalinas »

looping__lui wrote: post #40

I love innovation and stuff. Radical ideas. But the aviation market is one of the most heavily regulated - bureaucracy beyond comprehension. Did you ever wonder why Piper or Cessna airplanes look EXACTLY what they did 50 years ago? And why the engines used in these planes (e.g., Lycoming) are referred to as “Lycosaurus”!? If you go for a sightseeing flight with a local aeroclub - you will find the pilot spending 30mi…

Seems like you lack of understanding about aviation in general.

You know why Piper/Cessna airplanes look exactly the same and keep using 50 year old engines? because of safety.

You know why pilot spends 30min pre-checking the aircraft? safety

You know why getting a pilot license is magnitudes more work? safety

Everything in aviation works around safety. If you want to innovate, sure, go ahead. If you want to innovate and do it safety and reliable, oops, that's going to cost you a lot and that's the same reason why there are not many players in aviation, engineering an aircraft or new powerplant is a big up-front cost with probably little return.

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

#253

Post by userbinator »

NickNameNick wrote: post #216
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…

Car horsepower and airplane horsepower are very different things. A car engine has to be able to maintain peak power output for a few seconds while accelerating. maybe a few seconds, unless you're towing a load up a hill or something. On level ground you're using a small but variable amount of your available power. An airplane engine has to maintain peak power for the entire climb-out, and a substantial fraction of t…

unless you're towing a load up a hill or something

This reminds me of how a lot of people are surprised when they find out the engine of a typical semi-truck has "only" a few hundred HP but several times the displacement of a passenger car engine rated at almost the same power. The car engine will wear out quickly at continuous full load, whereas the semi engine is designed to run at full load continuously. Ditto for engines driving generators and pumps --- full load is normal load.

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

#254

Post by bhupy »

runarberg wrote: post #222
renewiltord wrote: post #204

Earlier quoted context omitted.

It's always been the case. We linked the world via trade in search of making a rich man's food taste better. I don't think it's sad. I think it's wonderful. The rich 'subsidize' progress for everyone. All of the things you mention (except the 3-point seatbelt, perhaps) have a story just like this one with some guy saying things just like this guy and a veritable shower of lament with no effort behind it.

> 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…

“Trickle down theory” has not been “debunked” by economists because it’s not an actual economic theory. It’s a pejorative used to criticize tax cuts.

Also the fact that technological progress/experiment typically (but not always) targets the top end of the market and works its way down is not controversial.

This phenomenon is also not what most people mean by “trickle down economics” as it relates to the pejorative against tax cuts which, again, isn’t a real theory peddled by credible economists.

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

#255

Post by dreamcompiler »

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…

> I personally look forward to the mainstream introduction of diesel engines into the US market that are able to run on Jet-A.

Seconded. 50 years ago diesel engines were too heavy for light aircraft, but the weight problem with diesels has been solved.

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

#256

Post by dreamcompiler »

Stevvo wrote: post #229
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…

There's no technical reason light aircraft engines can't be a heck of a lot better than turbocharged, fuel-injected pistons. They could all be cheap turbojets designed for low altitude flight burning regular diesel at 10gph going 300 Knots, with far higher reliability than any piston. Unfortunately for the reasons you mentioned, and the myth that turbines can't be efficient at low altitudes, nobody is going to develo…

Eclipse tried it and went bankrupt. But it was a nice idea.

https://en.m.wikipedia.org/wiki/Eclipse_400

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

#257

Post by praveen9920 »

AtlasBarfed wrote: post #173
praveen9920 wrote: post #38

Earlier quoted context omitted.

One word: compliance. FAA has lot of restrictions to allow a planes to fly with pilot in it. Imagine convincing them that without pilot.

You know that passenger planes basically can land with autopilot now?

No they cannot. Not in all situations.

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

#258

Post by praveen9920 »

protomyth wrote: post #116
praveen9920 wrote: post #38

Earlier quoted context omitted.

One word: compliance. FAA has lot of restrictions to allow a planes to fly with pilot in it. Imagine convincing them that without pilot.

In limited situations that is happening now: https://www.garmin.com/en-US/autonomi/ Autoland has achieved FAA certification. It’s now available on select G3000® flight deck-equipped aircraft. And it’s coming to more soon.

With a pilot behind it.

Driver/Pilot less is not approved anywhere in US

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

#259

Post by dreamcompiler »

wpearse wrote: post #223
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…

US$5/gallon is about the same price as our vanilla automobile juice here in NZ. We pick up avgas (half the price) from the small airport near us if we’re doing strictly off-road activities in our vehicles (no fuel tax).

Interesting. I had assumed avgas was more expensive than auto gas everywhere but I guess not.

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

#260

Post by praveen9920 »

Jabbles wrote: post #56
praveen9920 wrote: post #38

Earlier quoted context omitted.

One word: compliance. FAA has lot of restrictions to allow a planes to fly with pilot in it. Imagine convincing them that without pilot.

I'm sure it would be a decade-long task. But I'm not sure it's monumentally harder than either the process for piloted aircraft, or the task of automating the aircraft in the first place. And you can much more easily demonstrate the limits of an automated aircraft. Simulated bird-strikes, thunderstorms, power-outages, emergency landing in fields, blinding by laser-pointers, stray bullets or whatever scenario the FAA…

It is not just about regulations for the sake of accidents only, It is matter of national security as well.
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