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

lilium.com

131–140 of 334 posts

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

#131

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…

Totally agree about the certification. It's so annoying having to do stuff like managing the mixture. There is absolutely no chance I'm going to be better at that than even the most basic FADEC system. Every car since the early 90s has done away with the choke, but for some reason in a 2020-built C172 I still have to do this... :X I would argue that this insistence on safety certification makes actual flights less sa…

Lycoming/clones with fuel injection, you typically only mess with mixture when starting and stoping them.

There is of course a minority religious sect within GA who follow lean-of-peak theory and mess with their mixture constantly for better mileage (and possibly better wear, but that can go either way).

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

#132
post #113

This to me is a true moonshot and venture-worthy idea. Some of these concepts may be technically or economically infeasible—it's a major risk—but the pay-off for human wellbeing is phenomenal. I wish we celebrated more companies like these, but it seems like most of them are met with (well-earned) skepticism rather than genuine curiosity. The world of atoms is harder than software, but it's awaiting disruptions like…

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.

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

#133

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…

You paint it to in a overly negative light, in my opinion. Much of the processes and procedures in place are not just functional, but behavioral training and conditioning to enable the pilot to troubleshoot mid-flight problems. It's like a highly capable human runtime exception debugger that will save the lives of everyone on board.

Some FAA regs and procedures are written in blood, but most are written in a way to prevent blood in the future.

I also like to echo the products Garmin is incorporating to increase the UX in the cockpit. They address some of the things you outline.

Remember, aviators aren't engineers, they are operators. The license requirement is there to ensure that pilots can do basic things like triage, malfunction diagnostic, ad hoc solution generation, energy management, communicate, etc.

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

#134

This isn't going to be certified and allowed for part 135 operations inside at least a decade. Boeing can't keep their jets from crashing due to simple trim control software, what makes anyone think the FAA is going to go along with these flights over densely populated areas? This feels a lot like when everyone was scrambling to start helicopter taxi services which promptly crashed and burned... Helicopters were a ma…

Fly routes over freeways so they crash there.

Society will learn to tolerate 4-6 deaths at a time, but not on the 737 scale.

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

#135
post #122
post #33

Earlier quoted context omitted.

Most of the "uncomfotrable-ness" of smaller aircraft is how easily they are blown around in the wind, which is not insignificant at safe operating altitudes. This aircraft proposal will not be able to negate the effect. Think small boat on a lake - even with azimuth thrusters, still bobs up and down back and forth with the waves. Larger boats don't experience the effect as much, due to mass - same with large airliner…

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 it would first need to detect the movement, accounting for normal wind-speed, etc. Any solution here would be heavy, induce drag, eat through batteries/fuel, and introduce a lot of new failure modes that don't exist with traditional aircraft and could be unrecoverable in the event of a failure (stuck appendage or azimuth thruster-like propeller in wrong direction, destroying lift).

Things are quite different just 1,000 feet off the ground, and even worse 5,000 ft or 10,000 feet. The wind speed can get extreme, averaging 100mph at 10,000 ft[1].

For people accustomed to flying in these small aircraft, you get used to it. But for people already nervous about flying, or not familiar with small aircraft, the sudden movement can be very disorienting and scary.

People often underestimate the aviation industry. It's incredibly safe, and very stable. A lot of innovations were paid for with blood during the early days of aviation, which led to it's maturity. Innovation, at this point in aviation's history, is very challenging and requires very deep understandings - even mature organizations like Boeing struggle with this from time-to-time, and they have a ton of experience in developing extremely reliable aircraft for not just transport, but combat and more.

Unfortunately, far too often, things like this startup's solution are dreamt up by people that don't understand the problem domain and don't have a lot of experience in the field. They look from afar, and confidently state they know a solution no one else has thought of or tried, and the entire industry is simply doing things so obviously wrong. Fortunately, they often find out why things are the way they are within a reasonable time frame and don't blow all of their investor's money or get people killed. Time will tell here.

[1] http://www.kitegen.com/en/technology/wind-data/

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

#136

> If we imagine for a moment that you work in an office in Palo Alto, you could now choose to live in Hayward (5 min flight, $25), downtown San Francisco (10 min flight, $50), or even San Rafael (15 min flight, $70). This is a strange example to include in here – that's a pretty expensive (one-way?) commute.

Right? Because SF isn't already expensive enough without having to compensate employees for $700/week ($36,000/yr) in commuting expenses. (Or for employees to be able to justify that on their own dime...)

It wouldn't have to be every day; it'd save 1hr+ over driving or train; many people in the Bay Area market for this have an effective rate of compensation over $100/hour.

With sufficiently-enlightened regulation (for which I wouldn't hold my breath), these could run, for example, from the rooftops of Google buildings in Mountain View to the rooftops of their Embarcadero-SF building. Or downtown Palo Alto to a downtown SF pier. Etc.

If physically possible, safe, & available for the prices they're claiming, this would have a big market. And, competitors, like the Larry Page-backed 'Kitty Hawk': https://www.bizjournals.com/sanjose/news/2020/06/04/larry-pa...

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

#137
Flying a single person or two, with VTOL? That's an incredibly high expenditure of energy per person-meter traveled. Much higher than regular aviation, which itself requires a lot of energy.

Considering the prospects for decreasing availability of fossil fuel, and questions of climate impact, it seems to me that this is not sustainable on a mass scale, at all. I would guess this initiative will either become an alternative for the very-rich to using helicopters, or not get off the ground.

(... ok, that pun was a little underhanded, I admit.)

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

#138

Earlier quoted context omitted.

Yeah, what I'm not clear on is: what's the cost to fly from SF to Lake Tahoe in a helicopter? If it's a lot more than the $250 that Lilium is promising, what is it that makes Lilium cheaper? Is it just the up-front investment in scale and the route network?

Unrealistic business plan estimations not factoring in the true costs of operating an aerial vehicle... It’s a bit like “soon to be plane owners” that don’t quite pay attention when they are told the spark plug for their Cessna is 50USD, they need 8 for 4 cylinders and replace them rather frequently ;-) Changes when they realize that those companies chartering out planes for less than 200 USD/h probably don’t make lo…

> It’s a bit like “soon to be plane owners” that don’t quite pay attention when they are told the spark plug for their Cessna is 50USD, they need 8 for 4 cylinders and replace them rather frequently ;-)

That's supposed to be the promise of electric aircraft: almost all serviceable parts go out the window, just as with electric cars. Construction and maintenance costs are reduced to a fraction of what they are for mechanical systems. And because these are VTOL, ground expenses are likewise reduced.

Batteries are still rather expensive, though, and energy density sucks. The advantages may not be able to compensate, at least not sufficiently to hit a price point that appeals to a wider, non-millionaire market.

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

#139

This isn't going to be certified and allowed for part 135 operations inside at least a decade. Boeing can't keep their jets from crashing due to simple trim control software, what makes anyone think the FAA is going to go along with these flights over densely populated areas? This feels a lot like when everyone was scrambling to start helicopter taxi services which promptly crashed and burned... Helicopters were a ma…

Fly routes over freeways so they crash there. Society will learn to tolerate 4-6 deaths at a time, but not on the 737 scale.

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?"

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

#140

Earlier quoted context omitted.

Black hawks are quiet enough for specops teams to use them in urban raids like the Bin Laden one.

The rotorcraft used for the Bin Laden raid weren't standard Black hawks. The modifications probably required huge trade-offs in cost/performance and might still not be quiet enough for daily use in urban/residential areas.

Still not exactly anti-gravity.

Lilium boasts: "As well as a customized electric motor, it contains innovative liner technology which means the aircraft will be inaudible from the ground when flying above 400m and will only be as loud as a passing truck while taking off." https://lilium.com/the-jet

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