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Joby Aviation

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Yes, in general terms this architecture is a good compromise of disc loading, low prop tip velocity (noise), transition characteristics and low drag aero performance, However it’s a rather complex solution, with will inherently has some challenges with safety.

I see six motor rotating actuators , flap actuators, landing gear actuators, primary flying control actuators and probably wheel brake actuators. Are the prop blades pitch controlled (suspect so) ? It would be reasonable to assume all are electrical and probably half of them will be dual for redundancy hence maybe 20 without vp props & 26 + with). Linear electric actuators have the added challenge that they’re considerably more jam prone than hydraulic. All of this kit will be subjected to lots of vibration so would not have a happy life. The potential for resonance by modal coupling requires a comprehensive investigation in all flight, ground and failure conditions;- seriously hard core vibration analysis but quite manageable.

So how does it compare to a helo? Well in essence one big power gear box on the helo is being replaced by a plethora of smaller low power gearboxes and ball screw drives. My guess is that a lot of the propulsion simplification gains are eroded by the increase in control system complexity. So it will be more in line with Helo safety standards than fixed wing. If VP props this will present a big problem;- just ask anyone who’s owned one. Operation costs largely depends on battery technology, which is not transferred from the auto sector, due to the operational cycle, in particular the large power demands for hovering its bespoke, therefore expensive. The large cyclic power demands tends to adversely impact battery life, thus this will dominate the cost. These cost are only known to a few close to the project and everyone else is just guessing.

The one area that’s unexplored within these concepts is all weather operation. If you’re business model is based on a commercial operation then it’s not a nice to have. Electric de icing is power hunger, props can present unique difficulties as do high performance CFRP sandwich structures. All this will impact availability and maybe range.

All that said, of all the eVTOL schemes, if any are worth a go, this is the one with the highest chance of working........but still no guarantee’s.
 
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TomcatViP

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The problem will also comes from traditional helicopters that could close the gap in cost with the advantages of safety and adaptability when realistic revenues and pricing from those platforms start to come into scrutiny.

The counter effect might be deadly for many models outhere.
 

yasotay

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While a very attractive aircraft I have to agree that the complexity, and thus operating cost will make it tougher to get past the bottom line, especially when there are other feasible options in the pipeline. If it were focused on longer ranges (like the northeast corridor in the US) than most EVTOL concepts, thus avoiding airports all together, there might be a more compelling argument.
 

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