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Every time I see a multirotor carrying people, I think of the many times while building them at the beginning of the drone renaissance that I saw 4/6/8 bladed multirotors have an AP failure, a blade break, a speed controller overheat, etc etc and it fell out of the sky, literally.

These do not have a glideslope!

Sure, a ballistic chute might prevent an onboard tragedy but I continue to wonder about what the flying car gets parachuted onto. What fires get started? Who gets crushed?

Super cool tech. Huge accomplishment for the engineers involved.

I want to know how this makes a safe unpowered descent.




Statistically speaking, powerplant failure is not a leading cause of accidents for general aviation aircraft. A small popup thunderstorm will rip this thing to shreds like confetti. A moderately gusting 30-40kt crosswind will result in this thing landing upside down in a ditch. A lightning strike from 10-20 miles away will result in an entire wing shearing off. Hit some precip on a cold day and structural icing will take this thing down in minutes.

Speaking as a pilot, if I were flying (or being flown) by this thing, the electric powerplant would be the least of my worries.


This is why they'll never work in areas with weather as such. Certainly limits the geographical areas where they would be practical.

In rain, people would have to resort to ground based transport, so it doesn't really solve the problem. Transportation has to deal with weather. In the future, when batteries are light and powerful enough to run heavy aircraft (ie. Less vulnerable to light winds) vstol craft will be more practical. So much is waiting on Kw per AA sized battery.


Meteorologist here. Every place on Earth has weather as such. Frequency is different for different places, but everywhere experiences those conditions multiple times a year (at altitude, hazardous conditions as such are far more frequent than on the surface).


I don't know much about this aircraft but this appears to be a winged aircraft which unlike quadcopters and helicopters,losing an engine or rotor does not translate to a crash(?) because it had n number of rotors on each side,if one is lost,you lose altitude maybe and turn off matching rotors on the other side,which naively appears safer than a helicopter.


Wings don't help if you are below the stall speed.


Isn't that true for all winged aircrafts?

By all means let's hold the Heaviside to the same high safety standard as other aircrafts, but not higher.


> Isn't that true for all winged aircrafts?

Indeed it is, and my comment should be read in the context of the post I am replying to. Having wings gives Heaviside an advantage over purely multi-rotor aircraft most of the time, but during VTOL operations, there is a stage where the wings do not help.

Helicopters have an advantage over all other VTOL aircraft in that they can autorotate, though this is especially tricky in lightweight helicopters, on account of a lack of rotor inertia.


Emergency JATO? :D


Could be, I hope so. I really want to ride in one if they are indeed safe. With all of those motors and props in the air, that's a whole bunch of parasitic drag if it is able to glide.


For public transport or work commute,they don't need to fly that high. Maybe worst case they will be allowed at low altitude over water ways or low enough to where pre-emptive air-bag deployment would make it safe. In many ways hover craft is safer than cars I think,mostly because of the space available and lack of breaks (they say most car fatalities happen when people hit the break out of panic).


>I want to know how this makes a safe unpowered descent.

the wings seems to be enough for reasonable unpowered gliding. The canard design naturally helps prevent stall. And i'd be surprised if the engines on production models aren't split into 2 completely independent groups (given their number - 3 per/wing - on that prototype i think they aren't split) with completely separate power, controllers, etc, so even relatively serious failure would still leave you with half the engines - that would allow while uncomfortable, yet still controlled even vertical landing from lower hover which i'd suppose would be the worst situation to lose engines.


This is one of the reasons why this craft and the Airbus vahana craft have at least eight motors and propellers.

Serious camera carrying octocopters for filming are strongly preferred over quad and hexacopters. They often carry $60,000 RED or Arri camera+lens combos. In a quad, motor failure is a guaranteed crash. In a hex, it's extremely dicey. Octocopter design with eight separate ESCs is safer.

In many cases the battery system is still 1+0 non redundant, however. As is the flight controller.


> I want to know how this makes a safe unpowered descent.

That's likely one area where a helicopter would have a significant advantage.


Losing a motor isn’t really an issue on multirotors so long as you have >4 blades. Most autopilots have the ability to compensate for a motor loss.




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