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Comment by engineer_22 | Hacker News Reader

You repeatedly mention engines, but I'd point out there are no engines on this craft. This craft has electric motors.

I don't know if electric motors are more reliable than ICE, but I speculate that they are.

------ Edit, my opinion below:

VTOL is a HUGE WIN. It's the holy grail of flight. Fixed wing aircraft are inconvenient because they need a mile of flat blacktop for takeoff and landing.

Affordable eVTOL craft could change general aviation forever. The problem with helicopters is insane maintenance overhead and low fuel efficiency. The problem with fixed wing is you can't land it in your back yard. EVTOL is interesting in that it could bridge the gap between these two to provide a personal aircraft that has the best of both. Napkin math shows it's possible, and we're seeing some really cool products now.

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The VTOL only matters if it’s cheap. Most of the airports in the US are lightly used because general aviation is expensive, not because people are thinking “I would buy/charter a plane, but driving 20min to the local airfield is just not convenient enough”.

Typical general aviation aircraft (which this seems comparable to) need <1/4 mile runway (e.g. a Cessna 172 is less than 1000ft) which in the US means ~20k available airports.

My point being, the reason those airports are lightly used is driven by cost not that they inconvenient.

In any decent sized metro area inconvenience is a big deal.

My family had a weekend at a popular vacation spot about 80 miles from where we live (about 2 miles from the downtown area of Melbourne, Australia).

The drive takes roughly two hours door to door.

We’re in a suburb that happens to be on the right side of the city to be close to the GA airport, but it would be a 20 minute drive to the airport, say a 30-minute flight, and another 20 minute drive from the destination airport to our accommodation. If you could do the transitions between car-plane-car in less than 20 minutes total I’d be very surprised; net result, you’re saving maybe 30 minutes on the trip.

If you could put VTOL ports within 10 minutes walk of each destination (say 500 metres) you could cut the trip down to less than an hour.

To be fair, the amount of luggage you’d have to carry/push in this scenario might well still tip the balance in favour of the car for the holiday trip, but there are plenty of other scenarios where similar trips are made without the need to carry a mass of luggage where the VTOL is a massive win.

Fair points, but it think my point is this

Cost to drive (.50/mile) = $40x2 (round trip)= $80 @4hrs

General aviation 20min+45min (Cessna 172) + 20min= 1hr 25min x2 is 2hr 50 min (let’s call it 3hr) 1.5 hrs flying time @$300hr (let’s exclude cost of ground transport) means $450. So $270 to save an hour

If vtol saves another 2.5hrs for $270 and has the same cost profile, Than that’s great, you’re still spending >$100hr on time savings (and this optimistic, because I think most uses cases have lower ratio of airport travel time to flight time, you would then need to value your time at >$285k a year (pre tax @30% and 2000 hrs a year), which is not that huge a group of people

Yep, agreed - though I suspect it's a rather larger group than those who currently charter helicopters for transport.

For most people, "motor" and "engine" are synonyms. Is there a technical difference between the two terms?

There are people who feel strongly that one is only for electric, on non-electric, or combustion, or thermodynamic, or other classes of thing, kind of like a boat-vs-ship distinction. It is certainly more common to talk about an electric motor than an electric engine, for example.

That said, both terms have been used for a very long time for a very wide range of overlapping things. MIT has a nice history[0] of the words and why they are essentially synonyms in most cases (with engine being more appropriate to use in non-mechanical contexts like search engines and economic engines and motor being more appropriate to use as a gerund like motoring through something or motoring around the countryside).

[0] https://engineering.mit.edu/engage/ask-an-engineer/whats-the...

I thought the term was originally "motor engine" (a piece of engineering that produces motion) in the same way we can have a "compute engine" or a "siege engine" or a similar name for any other _ingenious_ creation.

From there we tend to shorten it to either motor or engine. Perhaps in current times people here the terms "combustion engine" and "electric motor" most commonly and assume there is an implied distinction.

I would trust motors over an engine any day. Look at the contraption that is an ICE: You have fuel-, oil-, and air-delivery systems... you have ignition systems... you have mechanical parts violently changing directions thousands of times per minute...

A motor is metal spinning in a magnetic field, powered by chemical reactions in a battery.

Which seems more likely to fail?

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