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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

#161

Post by errantspark »

Alupis wrote: post #135
yread wrote: post #122

Earlier quoted context omitted.

Couldn't you come up with some smart way of changing the throttle of the engines to keep you stable. Bit like these fins www.youtube.com/watch?v=4rCWnI8r_EQ

No. You're effectively in a liquid, and that liquid is moving very quickly up and down, left and right. You can see in the video you linked to, it's not all that effective, even while stationary in a boat. Plus, the drag penalty related to some extra appendage like this would be severe. It would take a LOT to keep you precisely in the same 6-axis position - and there's no way a system could react quick enough because…

To be clear I don't think that a bunch of motors with low latency control solve the problem of flying straight in turbulence. I think that it will allow for exploration of a new space of clever approaches to mitigate turbulence for craft with low inertia.

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

#162

Post by renewiltord »

runarberg wrote: post #132
tmh79 wrote: post #113

Earlier quoted context omitted.

I dunno man, im getting kind of jaded as I get older. "True moonshot" to me seems more like cheap clean water for everyone, or a real way to sequester carbon, not a way for rich folks to get to their country cottages faster.

True. This kind of technology would be a game changer for poorer rural communities with limited infrastructure and vast distances. Places like Greenland or East Congo. But this article did not mention this benefit at all. All they seem to care about is getting rich people between places they already can.

This is just basic marketing. You sell to the guy who can buy.

The Tesla company was started in 2003 to productionize the AC tzero. In 2005, the Roadster was conceived as the product it became and Tesla and Lotus tied up.

The Secret Master Plan arrived in 2006. So yeah, that's just how it goes. Because there is an army of people who lament things targeted at rich people, but that army does not participate in progress, either in money or in sweat.

The intelligent futurist always ignores them because they contribute nothing.

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

#163

Post by looping__lui »

renewiltord wrote: post #151
looping__lui wrote: post #126

Earlier quoted context omitted.

Let me rephrase: The innovation you describe (which is cool and needs certification) bumped the price for a new airplane from about 50k in the 70s (I guess we may be talking 200k in today’s money) to close to 1MM USD. And that innovation is “just” glass cockpit, and some more advanced avionics. Not changing the principles - you fly a bit faster, a bit safer but still need a license and do all the preparation and chec…

You only pay the R&D costs once. All you're saying is that you have to put a lot into R&D, but that's all on the I side of ROI. It was the same with SpaceX, the I part was huge. The question is whether you can make the R part work. And if you have scale, then the R part moves differently. It's the same with the first car you build. The first Tesla Roadster cost tens of millions to make. The second Tesla Roadster cost…

Well, the R side pops up when they optimistically tell you that your 20 min commute is going to cost 70 USD...

SpaceX is exactly the WORST example in this context: they just went ahead without all the bureaucratic overhead you find at NASA; they weren’t exactly transporting people at the beginning but cargo... And they had a pretty clear market with fat margins; those margins were fat due to the (unnecessary) overhead other agencies created.

You can’t do that in this case.

Put a bit differently: you can probably guess the magnitude of costs for a car to develop. In this case, I would be more than surprised if the get within a 10x magnitude in the end for their cost estimate and EVER get it certified. Again: there are currently NO guidelines how to certify that...

An example from Airbus and the A400 flagship:

https://en.m.wikipedia.org/wiki/Europrop_TP400

“Several technical problems delayed the engine's certification test program and pushed the entire A400M aircraft program into further scheduling adjustments. The engine delays were primarily due to problems with completing the full authority digital engine control (FADEC) software to the satisfaction of the civil authorities. More specifically, Europrop determined in mid-2008 that the engine worked correctly, but the FADEC software still did not meet EASA requirements.[27] Since the A400M was intended for humanitarian missions, the aircraft also needed to have a civil certification. Europrop did not realize that this meant the FADEC also had to show traceability and accessibility, so EASA denied civil certification of the software. Because of this problem, the first A400M test aircraft, which was flight-ready by September 2008, was not permitted to fly. Europrop had to triple the size of its workforce to fix the issue,[28] resulting in a FADEC system consisting of over 275,000 lines of code, which was four times more complex than the FADEC software for the largest civil jet engine.[29] Other problems included numerous plane subsystems providing insufficient logging to the main aircraft computer.[30]”

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

#164

Post by missedthecue »

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.

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

#165

Post by Alupis »

errantspark wrote: post #161
Alupis wrote: post #135

Earlier quoted context omitted.

No. You're effectively in a liquid, and that liquid is moving very quickly up and down, left and right. You can see in the video you linked to, it's not all that effective, even while stationary in a boat. Plus, the drag penalty related to some extra appendage like this would be severe. It would take a LOT to keep you precisely in the same 6-axis position - and there's no way a system could react quick enough because…

To be clear I don't think that a bunch of motors with low latency control solve the problem of flying straight in turbulence. I think that it will allow for exploration of a new space of clever approaches to mitigate turbulence for craft with low inertia.

Maybe. I'd like to see myself.

But, I'm highly skeptical for a lot of reasons. This design in particular introduces a lot of turbulent flow over the lift surfaces, and is going to require a lot of fancy logic to ensure the aircraft can remain stable with one or more of it's motors failing. It ads a lot of complexity, to a vehicle where simplicity keeps you safe, particularly at low altitudes where seconds matter when there's a problem.

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

#166

Post by looping__lui »

rklaehn wrote: post #119
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…

If US and EU are so buerocratic that innovation is impossible, there will still be a big market for viable VTOL electric planes in the rest of the world. Just like most 3rd world countries these days have better 4G coverage than supposedly 1st world countries like Germany, or rural US.

Check out: https://m.youtube.com/watch?v=_5K7cpxeXnc&feature=youtu.be

And guess the country :-)

I would never start such a business in the US or Europe.

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

#167

Post by getpost »

pdelbarba wrote: post #19
tschwimmer wrote: post #16

To me this marketing just looks like a slightly less expensive helicopter. It's great that we can travel to our ski trips or vacations a bit faster but it's not going impact the mobility needs of 95% of people. Why isn't anyone working on improving commutes through dense cityscapes? It's obviously a much harder problem but it's also a more important one.

I absolutely guarantee this will be anything but less expensive. You can get an R44 with better range and payload for a couple hundred thousand. This will be an electronic nightmare requiring extensive certification and maintenance efforts. Cessna can't even sell ridiculously old designs for reasonable prices due to certification overhead.

It might be less expensive due to the electrical powerplant. It will take a while before there is enough of a track record to know for sure. But, for example, electric cars are much lower maintenance than gas cars, as Tesloop as shown.

https://cleantechnica.com/2017/09/05/10492-tesla-model-s-mai...

https://www.tesloop.com/blog/2018/7/16/tesloops-tesla-model-...

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

#168

Post by runarberg »

byw wrote: post #157
tmh79 wrote: post #113

Earlier quoted context omitted.

I dunno man, im getting kind of jaded as I get older. "True moonshot" to me seems more like cheap clean water for everyone, or a real way to sequester carbon, not a way for rich folks to get to their country cottages faster.

This type of vehicle could be a game-changer for emergency response and rescue though.

Helicopters and ambulances are already pretty good at that. This vehicle seems to have some added restrictions (like landing capabilities) which would make it less good.

Helicopters are really expensive to operate though, so perhaps this vehicle could fit in if frequent flights would have to be made to a place without a road connection, such as to provide an emergency relief after big disaster.

Where it could be a game-changer is transporting people and light cargo in rural communities with limited infrastructure, such as East Congo or Greenland.

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

#169

Post by renewiltord »

looping__lui wrote: post #163
renewiltord wrote: post #151

Earlier quoted context omitted.

You only pay the R&D costs once. All you're saying is that you have to put a lot into R&D, but that's all on the I side of ROI. It was the same with SpaceX, the I part was huge. The question is whether you can make the R part work. And if you have scale, then the R part moves differently. It's the same with the first car you build. The first Tesla Roadster cost tens of millions to make. The second Tesla Roadster cost…

Well, the R side pops up when they optimistically tell you that your 20 min commute is going to cost 70 USD... SpaceX is exactly the WORST example in this context: they just went ahead without all the bureaucratic overhead you find at NASA; they weren’t exactly transporting people at the beginning but cargo... And they had a pretty clear market with fat margins; those margins were fat due to the (unnecessary) overhea…

That's a $250 flight which is mostly labour turned into a $70 flight without the labour. That's a marginal cost thing. It goes in a different part of the book.

I'm not saying this is doable but those numbers show nothing.

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

#170

Post by AtlasBarfed »

abraxas wrote: post #52

If flying in this involves the all-cavity search like for all other passenger flights then forgetaboutit. I'll take a train ride 3x as long just to avoid the hassle of the airport experience.

Or by the time it becomes reality, certainly highway self-driving will be a thing and you can take 2x the time but sleep/surf/work/whatever over 95% of the distance.

That said, it is so light that maybe it would be in range of consumer cost.

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