Flying taxi at the Paris air show is quiet – too quiet | Hacker News Reader

Flying taxi at the Paris air show is quiet – too quiet

wsj.com

61 pointslxm83 comments

> “That could be a weedwacker,” a Thales spokeswoman, Beth Larson, added.

This just reminds me how thankful I am to live in a city that has outlawed gas powered weedwackers.

How does that work - are professional landscapers permitted them? I'm so jealous of this but I doubt it would ever work here, in a large, bay area city.

It might just not work. I lived in a place where gas powered landscaping equipment was illegal and it was widely ignored.

It's a historic city with small lots which probably makes it a lot easier, and I think the ban only covers certain areas. I couldn't tell you all the details because I only moved here recently, but they banned selling a few years before banning using them. I do see some commercial landscapers still using those wide ones that you sit on like a throne and control with joysticks or something, and I'm sure a lot of people without permission still use gas powered but not on my street.

Electric trimming apparatus exist. On a 14 gauge extension cord you can safely have things on an ordinary 120 volt circuit with a 1500 watt motor, so there is more than enough power. Noisy, yes, but not as polluting as a small two-stroke engine and not nearly as loud.

There are cordless trimmers and leaf blowers. The run time isn’t great but they can use the same battery. Expensive to buy lots of batteries for whole day, and hard to charge on the truck. But I’m sure they will figure out some solution like quiet generator on truck, or multicharger to extension cord from house.

Solar panel and big batteries on truck, with backup generator?

EGO has a commercial line of battery powered equipment. In certain areas all electric lawn care can extract a premium even if gas powered equipment is legal.

The Stihl line are great - but pricey.

I hope to never start a 2 stroke again.

It will have to work. https://www.consumerreports.org/emissions/california-ban-on-...

Internal combustion blowers and line trimmers are legal here. All my neighbors have switched to electric blowers. The lawn guy also runs a fully electric setup with mowers, trimmers and blowers.

It’s not legislated. The battery gear is just simpler and more reliable. And the fact it’s quieter is a bonus.

Washington, DC, has outlawed gas-powered leaf blowers, and they seem to have mostly disappeared. Honestly I don't know about trimmers.

I’ve been so pleased with the overall ergonomics of my battery-powered lawn equipment that I’m not sure I’ll ever use gas-powered again. They usually operate around 80 decibels, they perform very well, and I’ve never had to deal with spilling gas or oil. I’m pretty sure I’ll never buy gas lawn equipment again.

I'm dreading a bit a future where the skies are swarming with flying taxis. Every urban view is guaranteed to be ruined long-term if this "takes off".

Still, maybe it would be ok to have this trade-off to solve traffic.

I'm more worried about risks of these falling from sky or making emergency landings all over the place. Specially in 10 or 20 years when maintenance goes south... Or someone hacks one for their own fun use.

Don't worry, your AR goggles will filter out whatever elements you don't like in a given scene. Personally I think it would probably look pretty cool so I'll leave them in.

Can the AR goggles make other people pretty? That would improve my quality of life.

I mean, even now, all the real time filters on Tiktok and Instagram are already capable of giving a no lag experience. When the more powerful AIs get stuffed into handheld devices, I expect them to paint the world however you want.

Apple is in prime position to do this btw. Their hardware is uniquely suited to AI stuff and now that they have officially step into the AR business, it is probably going to be strange.

Won't take long for Shallow Hal to become reality!

in your view, is our view of the night sky ruined by commercial airline flights overhead?

Commercial airline flights are packed with 100s of people and fly very high. Flying taxis are for n < 4 (likely n=1) people and fly low. That's like comparing bus networks with private cars.

Yes, and I want all those container ships out of the ocean too because they are ruining beach bathing. /s

Now that I think about it more, New York City made a pretty smart decision a long time ago to ban rooftop helipads.

There used to be a shuttle helicopter service from the roof of a tall office building near Grand Central station, to nearby airports, which was shut down after a helicopter tipped over on its side, throwing blades over the edge and killed five people.

https://gothamist.com/news/in-1977-five-were-killed-in-helic...

Interesting. Superman the Movie was filmed at the same time as this. I wonder if the helicopter scene (where Superman first goes public and saves Lois Lane) was influenced by this? Or maybe it was just putting to screen a pre-existing fear.

Are Americans ready to give up everything rather than admit that dismantling public transit/street-cars/rail and creating zoning restrictions for giant single housing-only residential areas was a bad idea and will cripple traffic for generations?

Autonomous cars do not solve traffic. Flying taxis will not solve traffic. Traffic is solved by abandoning the strange ideal of private cars/pick-up trucks with a single person inside.

Shared housing and shared transit has become gridlocked, initially because of industry forces and propaganda. But today, I think it remains for other reasons: Americans are scared of strangers (sometimes rightfully so) and public spaces are often depressing.

The interesting exception is commercial air travel, which to me embodies the worst parts of shared transit, yet is not considered socialist and dangerous here in the US.

Yes, I agree that a smooth transition will be unlikely if not impossible. It's not clear how to escape the spiral.

Zoning restrictions are a red herring. Even cities with liberal or nonexistent ones (Houston) have traffic issues, and even the most adamant anti-zoning activists rarely want to raise their kids next to a gas station or a liquor store.

It's the downtown-suburb hub-spoke city model, where everyone ends up on the road at the same time driving in the same direction.

Look at some cities designed from scratch with cars in mind like https://en.wikipedia.org/wiki/Irvine,_California The office complexes are decentralized, surrounded by shopping plazas, parks and schools which are then encircled by apartments, then semi-detached residences, and finally detached single family houses. Everyone with a job at one of the office parks can live closer to their specific job without affecting the traffic patterns of the other neighborhoods.

Even though it's very car-centric (with I-5 and 405 going through it), has next to zero public transport, is home to a regional airport, Irvine consistently ranks in the top 10 places for living / retiring / growing up / bringing up kids / park access metrics.

Where I live every supermarket and every kiosk is a liquor store and people raise their kids just fine.

And here government have monopoly on hard stuff. And people are happy to live closer to their stores... I have never heard anyone anywhere to say they don't want to live next to one. Though generally they are next to super and hypermarkets.

Individual transport will never "solve traffic".

I'm not arguing with you, I mostly believe the same. There are many cities though where public transport is such a foreign concept, that partial solutions will have to be a stepping stone for something better later.

Anyone have a sense of how the energy needed to fly something like this compares to driving an electric car the same distance?

We would have hover cars like we predicted decades ago if it is energy expensive. Lifting a vehicle and passengers is always costly in energy.

It is really a basic physics question, no? Air has little mass, and so provides poor thrust under Newton's third law of motion compared to a tire on the earth.

A car on the ground will always be more efficient than something which dumps its energy into air.

A small plane can carry 1-4 people at 120 MPH consuming about 11 gallons an hour, for a "MPG" of about 11 (miles in the air don't exactly translate to ground because air flows but it evens out over time).

Even with modern efficiencies available, I doubt they'd do more than double that, so a car would still easily win, unless the car had one person in it and the plane 4.

Time to resurrect the zeppelin, of course with better safety measures.

Airships never really went away, but "hydrogen go bang" is hardly their only problem sadly.

Hydrogen doesn't "go bang" unless mixed with the proper amount of oxygen. Usually, it just burns nice and smooth. Not much of a difference for anyone riding the airship though.

>>Usually, it just burns nice

Great choice of words to calm the passengers as we lose all our air worthiness.

wouldn't you recover the energy back while landing in same sense with car breaks that recharges the battery

There is constant energy expenditure to stay in air. Unlike with ground or sea vehicles that don't need it.

Yes, the technical term for that is "lift induced drag".

No, it's just drag. Extended landing gear is also a constantly expenditure but generates no lift.

> Extended landing gear is also a constantly expenditure but generates no lift

Negligible lift. Fluid flowing around an object generates lift. Drag is more intuitive; if there is drag, there is lift. (They're just components of the aerodynamic force relative to the direction of relative fluid flow.)

That's about the MPG of a hummer, so it's at least the same order of magnitude of cars.

Cars can't cross over lakes and mountains so there are advantages to having an airplane inefficient or not.

A Long-EZ carries 2 people and goes 1600 miles on 52 gallons of gas. So 31 MPG. That's at a cruise of 144 MPH.

So more like 3 times better performance is available with a modern design... Kind of makes you wonder...

https://en.wikipedia.org/wiki/Rutan_Long-EZ

I'd assume that for very short trips lift off and landing consume a large fraction of the total fuel.

Not for a typical small plane. Takeoff fuel burn isn't that much higher than cruise, and descend and approach fuel burn is similarly lower due to reduced power.

There are people who hypermile on planes and they have all sorts of tricks, including using updrafts when possible.

The most extreme ones fly without an engine at all (gliders).

I doubt that those techniques work very well in areas where you'd be able to run a successful air-taxi business.

The wind component averages out over time or is slightly in favor of the aircraft because you would aim for optimal wind by selecting a preferred altitude.

But air miles and car miles are not equal. The car route is nearly always longer, even in flat terrain roads don't usually go in a straight line to the destination. Adding in mountains or water makes that worse for the car.

For example driving Amsterdam to Barcelona is 1554km according to Google Maps. The flightplan route is 1236km and usually the really flown route is a bit shorter if ATC allows. That's 20% less miles for the airplane.

I think (not an expert though) that a multicopter like this is fundamentally less efficient than a helicopter. It has to do with the surface of the rotary wing (many small props cover less surface than a single big one).

I know that's not answering the question about the car (btw electric or not doesn't fundamentally change the energy question, except that electric cars like Tesla tend to be heavy, I would say), but still I find it interesting.

> many small props cover less surface than a single big one

Well, things change when you make a lot of small props.

This one has an entire ring of them, and they fit a larger outer diameter than a helicopter would. That's quite possibly the reason they are quiet, because they have more propeller area, operating on a smaller speed.

Very likely, here the amount of noise is a better guideline for efficiency than the usual characteristics of the basic design.

(There is no mention of the cost. It is the first thing to suffer when increasing the propeller area.)

Anyway, about the car question, the article says it is as noisy as a small grass mower... I guess an electrical car is much more silent than this.

A friend working on this type of technology mentions that altering the frequency at which sound is emitted to those outside the human hearing range can make a big difference.

One small propeller is less efficient than one big propeller. What drives the efficiency really is the ratio of propeller surface area to mass. So a lot of small propellers are roughly as efficient as a big one. Actually bonus point for the propellers being twisted, which is not possible on helicopters.

There are videos online of a cyclist pedaling a craft with enough energy to lift off the ground. Mind you, it was a purpose built craft in a very staged environment with an Olympic level cyclist, but you can still use that as a baseline for how much energy you need to lift a human aloft.

18 motors - that's the kind of high availability that feels safe.

I'd be interested in whether the power source is a SPOF.

The company hasn’t disclosed its pricing model, and the aircraft’s limited routes and capacity—one pilot and one passenger—might curb broad use initially.

Why would you put a pilot in the aircraft? He's not actually controlling the balance of the rotors, so why can't he be remote? If computer control fails the thing is cratering regardless of what the pilot does. Putting him in it is just wasting energy for no reason. "The pilot is less likely to run into something if he'd die along with the passenger" is that it?

Maybe the pilot is collateral to prove to the customer that the company has some stake in the thing not crashing.

No, there are aviation laws that require a human pilot to be present.

I absolutely want a pilot in the aircraft. Things go wrong and fail, you need someone trained to respond

Fly-by-wire systems have proven very safe. Most Airbus passenger jets are, for instance. But radio links for remote piloting are less reliable, because interference can be impossible to predict.

> why can't he be remote?

If the pilot is remote, then there is a radio link somewhere. That increases the surface for failure. It is hard to keep a reliable radio link.

I wonder if this has a parachute? If not, I'd feel better in other drone designs that have wings that would let you glide, which would also be better for range.

The picture shows it is registered as D-M... which is german ultra-light (600 kg max). They are required to have one, unless it can auto-rotate. Maybe there's additional exceptions. And the production model might not be ultra-light.

An electric multicopter would be wonderful for short distance over either water (e.g. PR main island to Vieques) or mountains (not having to have access roads, or being able to go straight-line for passengers, and a much longer route with switchbacks from a major road back into mountains. Eagerly awaiting aircraft like these; something <$500k and 100kg (ideally 200kg) of load, low speed, 30 mile range would be perfect.

There seems to be many entrants to this new sector of aircraft manufacture. I'm always left with the same 2 questions, unanswered.

1. What's the generic name for these aircraft vs "Helicopters?" 2. Whats the advantage of these aircraft vs Helicopters?

1. I think we’re still deciding. 2. Quieter, easier to pilot, no fuel smell or storage.

on the other hand . no range.

1. I propose "more quiet helicopter"

1. I call that a multicopter. There are specialized names for multicopters: if it has 4 props, "quadcopter". 6 props: "hexacopter". Octocopter, etc. Some names give an indication on the configuration. Say you have something that looks like a quadcopter (so a square with one prop on each vertex), but each prop is doubled (so there are 8 in total: 2 "squares" on top of each other). Then I call that a "coax octocopter".

Same for VTOL (vertical takeoff and landing) vehicles. I usually use VTOL to mean "a fixed wing" (i.e. something that looks like a plane) that takes off and lands vertically, but there are different configurations. A "tiltrotor" will have the rotors facing up when taking off, and then the rotors will tilt to face forward during flight. A "tailsitter" will have fixed rotors, but the vehicle will takeoff like a rocket (so "sitting on its tail", I guess), and then transition to forward flight.

You can refer to this list before naming that -copter

https://en.wikipedia.org/wiki/IUPAC_numerical_multiplier

If enough of us are saying Tetracopter, it will stick.

I vote for aeromobile.

2. I wonder, too. In terms of energy, I think the helicopter is the most efficient (it has to do with the surface covered by the prop, where one big rotor covers a bigger surface than many small ones).

Then in the startup world, I think it is more sexy to VCs, because that's new. Who would be interested in an autonomous helicopter? That's has-been, right?

Tldr: flying around an extremely loud airshow with constant roaring of low flying jetengines drowning out the accompanying max 'epicness' accompanying mood sountrack blaring from the PA, the engines of this vehicle failed to turn enough heads up from people that were on their phones, according to published wsj infomercial by wannabe flying taxi seller.

Looks like fun and games until someone puts their hand through prop.

Will this be any better than helicopter from noise point of view? Or safety?

Any machine can be perilous; cars don't have a good track record compared with planes.

Debut of Volocopter’s electric-powered air cab is drowned out by roaring jets and helicopters at air-industry bazaar

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