SureFly – a personal helicopter designed for safe and easy flight
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Re: SureFly – a personal helicopter designed for safe and easy flight
#2What is the benefit of more, smaller rotor blades over fewer, larger ones?
I thought that the area of air that the blades worked on scaled with pi-r-squared, which favours fewer larger rotor blades, as seen on most helicopters?
Re: SureFly – a personal helicopter designed for safe and easy flight
#3What is the benefit of more, smaller rotor blades over fewer, larger ones? I thought that the area of air that the blades worked on scaled with pi-r-squared, which favours fewer larger rotor blades, as seen on most helicopters?
I can't think of any benefits of this layout other than reducing the size of the landing field you'll need. And I guess less complexity on the part of the rotors, no tail rotor with associated dangers etc.
I can think of some significant downsides though.
1. This is fixed pitch, not collective pitch. That means any change in the attitude of the aircraft requires one or more sets of rotors to change their speed of rotation. This means that you need top notch electronic control systems, gyros etc. to mediate between pilot input and what the aircraft does. These electronic systems are sensitive and fragile and degrade with time. And when they let go, it's spectacular.
2. A loss of any one of the 8 motors is a Jesus Christ, yank the ballistic parachute moment. This is likely a hull-loss event as there will be all sorts of load-bearing parts with the job of absorbing the opening shock of the parachute. These will at minimum require inspection prior to the aircraft being certified airworthy again.
3. related to 2 above, this aircraft has no capacity for autorotation whatsoever. A traditional rotary-wing helicopter with collective pitch can autorotate safely in to a controlled landing in the event of an engine failure. If you lose an engine in this, and your ballistic chute tangles or doesn't deploy properly, you are proper fucked.
It's cool, and quad-copters are fantastic cargo and gp platforms. But I would never fly in one.
Re: SureFly – a personal helicopter designed for safe and easy flight
#4I thought gasoline turbine generators are sort of here (used in hybrid buses), womder why they stuck with piston generator.
Also, any ideas what battery pack you’d need to do the same 70miles?
Re: SureFly – a personal helicopter designed for safe and easy flight
#5Wait:
- Curb Weight: 1100lbs
- Max Takeoff Weight: 1500lbs
So... you, your passenger, and any cargo combined can't weigh more than 400 pounds? That's a pretty serious limit for people hoping to transport multiple adults. And "precision agriculture" or the sorts of practical uses they discuss all go right out the window.
Re: SureFly – a personal helicopter designed for safe and easy flight
#6Flying fixed-pitch copters is risky. The question is: more risky than driving in traffic? More than taking the bus or swimming or eating fatty foods or a hundred other things we do without blinking?
Still, it'll have to have a measured safety record before I'd want to fly it. Better yet, automate it to go from heliport to heliport in a crowded city, a sort of aero-lyft. So I don't have the chance to screw anything up. Because I'm thinking the human operator is going to be the root of any accident stats. Imagine a swarm of these over your city, with humans in control.
Re: SureFly – a personal helicopter designed for safe and easy flight
#7Wait: - Curb Weight: 1100lbs - Max Takeoff Weight: 1500lbs So... you, your passenger, and any cargo combined can't weigh more than 400 pounds? That's a pretty serious limit for people hoping to transport multiple adults. And "precision agriculture" or the sorts of practical uses they discuss all go right out the window.
Its perfectly fine for two adults + a bit of cargo for immediate use.
Re: SureFly – a personal helicopter designed for safe and easy flight
#8Wait: - Curb Weight: 1100lbs - Max Takeoff Weight: 1500lbs So... you, your passenger, and any cargo combined can't weigh more than 400 pounds? That's a pretty serious limit for people hoping to transport multiple adults. And "precision agriculture" or the sorts of practical uses they discuss all go right out the window.
I'm sure the Max Take Off weight is even lower at altitude and in warm weather. I've noticed most R22 pilots are pretty skinny.
Re: SureFly – a personal helicopter designed for safe and easy flight
#9Wait: - Curb Weight: 1100lbs - Max Takeoff Weight: 1500lbs So... you, your passenger, and any cargo combined can't weigh more than 400 pounds? That's a pretty serious limit for people hoping to transport multiple adults. And "precision agriculture" or the sorts of practical uses they discuss all go right out the window.
The BMI chart maxes out healthy weights at 192. So unless you have two NBA players or something, it should work well for most but perhaps not all healthy people.
Re: SureFly – a personal helicopter designed for safe and easy flight
#10What is the benefit of more, smaller rotor blades over fewer, larger ones? I thought that the area of air that the blades worked on scaled with pi-r-squared, which favours fewer larger rotor blades, as seen on most helicopters?
I can't think of any benefits of this layout other than reducing the size of the landing field you'll need. And I guess less complexity on the part of the rotors, no tail rotor with associated dangers etc. I can think of some significant downsides though. 1. This is fixed pitch, not collective pitch. That means any change in the attitude of the aircraft requires one or more sets of rotors to change their speed of rot…
> A traditional rotary-wing helicopter with collective pitch can autorotate safely in to a controlled landing in the event of an engine failure.
But not in the event of a propeller or pitch-control failure. Also probably single propeller failure in this quad will mean "we lost 1/8 of power, we must land". Also if you lose gasoline engine, you have battery backup for 5min.