Originally Posted by
27/09
Andy,
The laws of physics can show why Mr Wright et al were not pursuing a folly.
Right now logic says this concept will not fly, current laws of physics, economics and logistics can show what this will likely not work. True, never say never, but tell me how you think this might work.
Originally Posted by
neville_nobody
Go have a look at the 80 odd year history of tiltrotor operation and tell me what Uber knows that everybody else doesn't. If Boeing have trouble with the concept why on earth are a IT company going to solve it? Unless someone has a technological breakthrough this is going to be a nonstarter. That's before you even start thinking about battery powered aircraft.
Whilst I agree with you that a tilt wing/rotor is a desirable, perhaps necessary aspect of a viable eVTOL solution, I think to suggest that Boeing "having trouble with the concept" as a bar to all others being successful is painting with a broad brush indeed! Sure there's been some issues since the XV15 days and the V22 isn't without issues but that hasn't stopped the roll-out of the V280 nor the AW609. All of these craft are monsters compared with what I think is necessary for an Über air taxi business model They also offer good lessons in what actually works in real life.
Having said that, I believe the air taxi idea, whilst one way of attracting funds to aid development, is a step too far too quickly. Sure, it may come eventually but I think a personally-owned eVTOL, perhaps starting in the experimental category - possibly even as an E-AB makes more sense, at least initially It's undoubtedly a huge new area of possibility with lots to explore and many lessons to learn. The technology will be developed. The real question is where and who will own the rights to it...
As far as it being a viable possibility, I believe it already is now with current tech. I haven't seen any proposals made public that to me look aerodynamically viable but I have been doing my own design calcs on a single-seater concept and at 650-ish kg MTOW yields a 135kt/250km/h cruise speed for a 100km/54nm range with a VTOL each end. That's about 25-30kWh worth of energy, I think. One key question remaining is what reserves are likely to be required for electric aircraft since demanding 30mins when the maximum range flight time is only 25mins seems a bit extreme and would kill the idea dead at this point in technology.
As far as Über et al being IT companies and not aerospace companies, I don't see the issue here since it isn't skills or expertise they offer but rather financial muscle and backing. The real expertise needed is usually readily available if you have money to spend.
No, I don't believe we'll have viable air taxis in the time frame predicted here but we sure as hell should be playing about in this sandpit well before five years has elapsed.