Hacker News Reader

Comment by fortytw2 | Hacker News Reader

I think you're neglecting to think about moving people around in rural and or remote areas. Where I grew up (eastern NC) the ability to travel as-the-crow-flies would massively cut down on time to get places, many roads take 30-45 miles of driving to go what might be 15 miles in the air.

In that kind of area, there's not the population density to support any kind of mass transit (or even really taxis) and the distances are too far for biking to be practical. Readily available electric VTOL would revolutionize rural America. Not much to worry about in terms of air congestion, either.

View on HN

Indeed, Alaska has this problem and worse. The region relies heavily on seaplanes and short-take-off-and-landing aircraft for logistics. These eVTOL aircraft would be great in Alaska and especially in places without lakes. Places without a lot of flat area for landing, places like Papua New Guinea, have no good options at all right now, so these VTOL aircraft will be transformative.

It’s not that difficult to learn how to fly a helicopter, you only need 20h with instructor before the first solo flight. While that’s just the beginning it shows getting the basic controls down is not the problem. Thus, these VTOL aircraft are only going to be game changers if they are vastly cheaper, which seems unlikely.

The real issue is unit sales being so low. The R22 is a popular and ‘cheap’ helicopter ranking #8 in total sales, but it’s sold less than 5,000 units worldwide over 40 years.

PS: Fixed wing aircraft are popular because they have a huge range of inherent advantages. VTOL sounds great, but the downsides are enormous.

VTOL share most of those advantages of winged aircraft. The reason eVTOL may well be cheaper is that they have a lot fewer moving parts than a helicopter (and much lower vibration, plus using cheaper, lower-maintenance electric motors instead of turbine engines) and much less (and cheaper) fuel. But it'll take good designs. The Lilium one seems non-optimal compared to the Heaviside.

And don't rule out eSTOL. I think we'll see more of that.

Helicopters have an operating cost per hour an order of magnitude higher than a comparable payload conventional aircraft. The purchase price per payload capacity is also nearly an order of magnitude different. It's not the operator cost that determines the difference in price between helicopters and CTOL.

It's hard to claim they're cheaper when they have a fraction of the range of gas helicopters. It's apples to oranges, the flying cars now are equivalent to electric golf carts in performance.

For those cases where their range is sufficient, they are vastly cheaper. And their range is going to increase over the years as batteries improve.

Helicopters are VTOL, I don’t know what you think it means but it’s just ‘Vertical Take-Off and Landing”. https://en.m.wikipedia.org/wiki/VTOL “This classification can include a variety of types of aircraft including fixed-wing aircraft as well as helicopters and other aircraft with powered rotors, such as cyclogyros/cyclocopters and tiltrotors.”

Similarly, an electric helicopter would qualify as eVTOL. People generally aim for something more efficient in flight, but that’s a separate question.

You’re right. I meant VTOL with wingborne cruise, like the V-22.

> Fixed wing aircraft are popular

Even so, only about 1000 single engine piston airplanes are sold every year.

But they last forever. For instance, there are still lots of single engine Piper Cubs (popular in Alaska for STOL capability) from the 1940s maintained, in use, and for sale:

https://www.controller.com/listings/aircraft/for-sale/list/m...

(Additionally, a lot of general aviation aircraft have moved to turboprop in the last few decades.)

It's about 500 single-engine turboprops per year.

You're right, they last forever, and so the market for new aircraft is tiny. Really a vicious circle: high costs lead to low volume leads to high costs.

The economics hardly make sense for a congested city. Forget it for a remote area.

If the population can't support a few car-based taxis, how is it going to support a more complicated VTOL taxi?

I guess the article is actually about taxis specifically, but if the technology exists, they could definitely be sold as personal vehicles for travel along paths that are very long by road, but very short by air. Making rural less... rural, if that makes sense.

The market is probably there if someone could pull off a 1-2 seat VTOL that had maybe a 60 mile range.

I can't see such a vehicle being any cheaper or requiring fewer licences to operate than a helicopter. And helicopters are already available if travelling 20-30 miles in a straight line is a problem you need to fix.

You may be right, but I don't foresee the pilot being allowed to control the vehicle. I imagine governments creating laws before long that would require all drone type cars to use GPS, take off and land from designated areas and would not permit manual control unless you meet some criteria.

In which case unfortunately, again, I can only imagine it would be 100x easier to just automate a helicopter rather than make a "flying car"(whatever that means) and then automate it.

I don’t know about the legal or other regulatory logistics cost of operating a helicopter, but the physical maintenance requirements for helicopters are likely far far higher than a potential electric vtol vehicle.

Why? Imagine a vehicle that in practicality performs the exact same job as a helicopter, has the same or actually worse failure modes than helicopters(helicopters can at least autorotate, most proposed "flying cars" can neither glide nor autorotate) and now tell me why would such a vehicle have any lower maintenance requirements? Sure it might use an electric motor instead of an engine, but surely safety would require the exact same maintenance regimen as an actual helicopter. This is not going to be a car that you can bring for an inspection once per year, pay £30, change some oil, cabin air filter and be done. It's going to be as costly as any other air-worthy machine to own, in which case any kind of comparisons to a personal car are frankly out of the window, and anyone who thinks they could build a business around one could build a business right now using existing machines. That's not to say that innovation shouldn't happen, quite the contrary - but the whole talk of "flying cars" for your Joe Shmoe is just a pipe dream.

I can think of some reasons: (1) redundancy, (2) economies of scale, and (3) changed regulatory regimes.

The flying car designs I've seen have no true redundancies. They look like they would be dangerously unstable if they tried to run on fewer than all motors.

The Volocopter has 18 rotors (fixed, electric motor, with 1 degree of freedom - doesn’t get much simpler) attached to 9 battery packs, and at least 4 can fail (even more when they are “nicely” distributed) and it's still controllable and landable. And they could still throw in a ballistic rescue parachute.

Unless of course the power supply fails, in which case we're back to the point I brought up earlier - you have neither autorotation nor gliding to fall back on, the vehicle just falls out of the sky like a brick - the parachute would help but I'm not sure how feasible that is.

Which power supply? According to the poster there are 9 separate battery packs which, presumably, are the power supplies.

> Why?

As people already pointed, redundancy. Those systems have a lot of engines.

The simplest ones have fixed engines, and the most complex ones have then engine move in a single axis. Both are much simpler than an helicopter.

Electrical motors inherently require less maintenance, what isn't as large a change as it seems.

All the e-VTOL designs I have seen can glide, what places them on the same category as airplanes, that require much less maintenance than helicopters.

> Both are much simpler than an helicopter

They are mechanically simpler, but aerodynamically and electrically vastly more complex. These designs are only possibly due to modern engineering, otherwise they would have been invented before the helicopter.

It's mechanical complexity that brings unreliability and high maintenance.

Electrical complexity is more reliable by orders of magnitude, and aerodynamics won't fail mid-flight.

Just to be clear, the VTOL in this article appears to be a light-sport aircraft (LSA) with a canard wing configuration. I assume it can glide like a normal LSA, though I won't swear to it. It is not an oversized quad-copter.

That said, if it is an LSA, at least in the US, it would have to meet the normal LSA or E-LSA regulations. Including the service schedule, which is less onerous and non-LSA general aviation, but still far more than a car.

Just getting rid of metal structural components would be a huge boost, that's why the Cabri G2 has zero life limited parts while the R22 has... many. The state of civil rotorcraft is analogous to that of commercial jets 25 years ago. All metal parts, little to no computerization. This isn't inherent to flying cars vs. conventional helicopter configurations, just due to the extremely risk-averse nature of the rotary-wing industry. Helicopters today are very under-optimized but still work pretty well. Think of how shitty old cars were in mileage and maintenance, but still got the job done, while new cars typically last over 100,000 miles.

Helicopters are much harder to fly than any of the flying cars in development. To become licensed for one, you're looking at spending around $20,000 in instruction and flying time. That's why so many helo pilots are ex military. Flying cars also put more emphasis on the noise reduction. Both of these priorities give them greatly reduced performance (speed and range) relative to conventional helicopters.

One imagines a similar middlebrow dismissal lobbed at those flying camera drones that started selling for personal use about ten or fifteen years ago... We already had UAVs; why would anyone think multiple tiny electric rotors were better?

A helicopter is enormously complex mechanically, hard to operate, and either failure prone (piston engine) or expensive (turbine). Sure an electric VTOL could be cheaper to operate.

The same way Alaska supports STOL and seaplane taxis.

It's also useful for people who live in island clusters, or islands that are short hops to a mainland. Boats are slow and often not on demand.

That’s a really interesting observation. Especially when it seems like all the automakers designs on selling subscriptions to an electric car on-demand fleet seems nonsensical for rural areas.

Reply on news.ycombinator.com