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Can anyone chime in how this aircraft is so energy efficient? It seems like the props on the wing will give a ridiculous amount of drag. Also, one of the key re

Can anyone chime in how this aircraft is so energy efficient? It seems like the props on the wing will give a ridiculous amount of drag. Also, one of the key requirements for an energy efficient rear prop plane is super laminar air going to through the rear prop for efficient thrust. The wing design seems to remove this advantage. Edit: Also, I thought smaller props for vertical flight is significantly less efficient than one large prop like a helicopter? That being said, I always had a soft spot for aircraft startup after working at one in my younger days. Pretty interesting to see how this ends up especially with Sebastian Thrun on the team.

assblaster 9y ago
I don't know for sure, but I think that autorotation of the multiple vertical rotors provide substantial lift even if they're not being actively driven, similar to the tree seeds that autorotate as they fall.
- Someone1234 9y ago
  Auto rotation converts air speed (i.e. drag) into lift. That may slightly reduce the relative costs of drag (by providing benefit) but it still has to be overcome by forward momentum.
  - fastball 9y ago
    But that's probably more of an issue for max speed than it is for efficiency, which would explain why it's operating speed is only 150kmph.
- syntaxing 9y ago
  I wonder if the auto-rotation is enough to overcome the drag from the huge wake they produce. The wake has to be almost the size of the aircraft with the wings oriented as so.
- mnw21cam 9y ago
  If you look carefully during the video, you can see that while in forward flight the rotors are aligned and locked in a forward position, which presumably reduces drag a fair amount. But yes, I can still imagine them producing a lot of drag.
- jccooper 9y ago
  From the video the rotors seem to park in fixed wing flight. The extra large hubs may be designed for lift generation, however.
starpilot 9y ago
It's not. It has a range of 60 miles and cruise speed of 93 mph, giving an endurance of 40 minutes. In fixed-wing forward flight, this aircraft is slower than an R22 designed in the 1970s, which can fly 240 miles at 110 mph. I have no doubt that they spent a lot of time optimizing the rotor/disk hubs on this thing for forward flight, but anyway you slice it, it's a very messy wing. That has compromised its performance in both forward and hovering flight, while gaining mechanical simplicity. What this is is a first step, and as battery tech improves, this is the right direction. But the performance is not impressive. This is like a self-driving electric golf cart you ride to get from your doorstep to the entrance of your gated community, in a world of Honda Civics that go 500 miles on a single tank.

assblaster 9y ago

I don't know for sure, but I think that autorotation of the multiple vertical rotors provide substantial lift even if they're not being actively driven, similar to the tree seeds that autorotate as they fall.

Someone1234 9y ago
Auto rotation converts air speed (i.e. drag) into lift. That may slightly reduce the relative costs of drag (by providing benefit) but it still has to be overcome by forward momentum.
- fastball 9y ago
  But that's probably more of an issue for max speed than it is for efficiency, which would explain why it's operating speed is only 150kmph.
syntaxing 9y ago
I wonder if the auto-rotation is enough to overcome the drag from the huge wake they produce. The wake has to be almost the size of the aircraft with the wings oriented as so.
mnw21cam 9y ago
If you look carefully during the video, you can see that while in forward flight the rotors are aligned and locked in a forward position, which presumably reduces drag a fair amount. But yes, I can still imagine them producing a lot of drag.
jccooper 9y ago
From the video the rotors seem to park in fixed wing flight. The extra large hubs may be designed for lift generation, however.

starpilot 9y ago

It's not. It has a range of 60 miles and cruise speed of 93 mph, giving an endurance of 40 minutes. In fixed-wing forward flight, this aircraft is slower than an R22 designed in the 1970s, which can fly 240 miles at 110 mph. I have no doubt that they spent a lot of time optimizing the rotor/disk hubs on this thing for forward flight, but anyway you slice it, it's a very messy wing. That has compromised its performance in both forward and hovering flight, while gaining mechanical simplicity. What this is is a first step, and as battery tech improves, this is the right direction. But the performance is not impressive. This is like a self-driving electric golf cart you ride to get from your doorstep to the entrance of your gated community, in a world of Honda Civics that go 500 miles on a single tank.