LSA Octocopter?

CT4ME

CT4ME

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CT4ME
The "SureFly" by Workhorse. Under $200K? 2019?
SureFly-3-resized.jpg
 
Light-sport aircraft means an aircraft, other than a helicopter or powered-lift that, since its original certification... FAR 1.1
 
The runners look rather tall. I get you want the spinning props way above people's heads; but it must be an interesting challenge to climb into the vehicle.

Tim
 
Landing gear looks to be designed by a ironworks dude from the 30's; a bit overkill.
How about the frontal drag from the rotor supports? Helps keep the top speed below 50mph I'd guess.
 
And what happens when just one of those engines has a problem ? Is Steingar and me the only people who thinks to ask this ?
 
Art VanDelay said:
And what happens when just one of those engines has a problem ?
Click to expand...
I think the video said you could loose 2 or 3 motors and still maintain control. Looks like there are 8 electric motors being used. Kinda cool don't know about the 70 mile limit for a flight though
 
AKBill said:
I think the video said you could loose 2 or 3 motors and still maintain control. Looks like there are 8 electric motors being used. Kinda cool don't know about the 70 mile limit for a flight though
Click to expand...

I don't see how it would be controllable even after the loss of one motor. I'd like to see that demonstrated - from a safe distance away.
 
Art VanDelay said:
And what happens when just one of those motors has a problem ? Are Steingar and I the only people who think to ask this ?
Click to expand...

Good gawd man, lrn 2 grammar, lol. You're worried about the failure of one motor out of 8? Do we have to bring out the old joke about the dreaded 7-engine approach in a B-52? I'm sure the other 7 motors can compensate for the loss of one, at least to get it on the ground without too much damage. Now a complete power failure would be the big issue, unless they have a way of simulating the rotor resistance of an autorotation. Then again, the chances of the power failure may be negligible, but that's a tough pill to swallow when your life is on the line.
 
SoonerAviator said:
Good gawd man, lrn 2 grammar, lol. You're worried about the failure of one motor out of 8? Do we have to bring out the old joke about the dreaded 7-engine approach in a B-52? I'm sure the other 7 motors can compensate for the loss of one. Now a complete power failure would be the big issue, unless they have a way of simulating the rotor resistance of an autorotation. Then again, the chances of the power failure may be negligible, but that's a tough pill to swallow when your life is on the line.
Click to expand...

And how exactly do you think they do a hovering turn ? Seems to me you'd need all motors working for any kind of control authority.
 
Art VanDelay said:
And how exactly do you think they do a hovering turn ? Seems to me you'd need all motors working for any kind of control authority.
Click to expand...

So, they can't use controller logic to make rotor speed/pitch increases in the other 7 motors as needed to achieve the desired result? Why not have it operate like a septacopter at that point?
 
Art VanDelay said:
And what happens when just one of those engines has a problem ? Is Steingar and me the only people who thinks to ask this ?
Click to expand...
I guess this happens:

With eight independent motors each driving a single carbon fiber propeller, a backup battery power system, and a ballistic parachute to safely land in the event of emergency, the SureFly provides unparalleled safety for a personal aircraft.
 
Lowflynjack said:
I guess this happens:

With eight independent motors each driving a single carbon fiber propeller, a backup battery power system, and a ballistic parachute to safely land in the event of emergency, the SureFly provides unparalleled safety for a personal aircraft.
Click to expand...
From 50' up?
 
Art VanDelay said:
And how exactly do you think they do a hovering turn ? Seems to me you'd need all motors working for any kind of control authority.
Click to expand...

I would think so too. And from a statistical standpoint, the probability of one rotor out of four failing is far higher than the probability of one rotor alone failing.
 
AKBill said:
I think the video said you could loose 2 or 3 motors and still maintain control. Looks like there are 8 electric motors being used. Kinda cool don't know about the 70 mile limit for a flight though
Click to expand...

Lose two motors on the same "arm" and I don't think the chute would save you. I'll let some one else prove me wrong! -Skip
 
GeorgeC said:
If you have six or more rotors, you can fly OEI. I would be more concerned with loss of power, because they can't autorotate.
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I'd be concerned about lack of power.

My reading is that he is using the 600cc BMW iDrive engine driving two generators for indirect motor drive. Battery is only a backup energy source. That engine outputs a whopping 34 horsepower in automotive form.

Elsewhere, I am inferring that he is driving the little engine at double the automotive rated output (68 horsepower?)


The engine is already in use in BMW products in several ways. In the i3 car, it is used as a range-extender, and the same convenient form-factor of the compact, narrow and flat engine is that it also provides the motive power for BMW's super scooter C600.

In being purposed for range-extending, the characteristics of the motor are considerably revised as the engine serves as a low-emission, high efficiency electricity generator – peak output of the motor is almost halved in the process.​

Even so, the specs look to be anemic at best. And what aeronautical company uses "Curb Weight" on a technical spec for an aircraft??

http://workhorse.com/surefly
  • Piloted Vehicle designed to carry pilot and passenger or pilot and cargo
  • Curb Weight: 1100lbs. Max Takeoff Weight: 1500lbs
  • Gasoline Piston Engine drives dual generators to provide power to prop motors
  • Dual Lithium Battery Packs: 7.5kWh each, used for emergency landing power (5 minutes) in the event the gasoline generator fails
  • Ballistic Parachute
  • 70 mph top speed
  • One hour of flight time available per tank of gasoline
  • Flight ceiling of 4000 feet.
 
Cmon guys, think outside the box. Give some of these new stupid ideas time to flush themselves out. You all sound like you work for the FAA, lol.
 
Art VanDelay said:
And how exactly do you think they do a hovering turn ? Seems to me you'd need all motors working for any kind of control authority.
Click to expand...

I bet in the 1940s you were yelling that they're crazy for trying to fly faster than sound...."They'll just hit an invisible wall and die..."

Sarcasm aside, I think you're missing the spirit of this post COMPLETELY!!! Say it with me now, "Gee, that's a neat concept. But I wonder what they've put in place to overcome a potential loss of power in one or more of the engines."
 
vkhosid said:
I bet in the 1940s you were yelling that they're crazy for trying to fly faster than sound...."They'll just hit an invisible wall and die..."

Sarcasm aside, I think you're missing the spirit of this post COMPLETELY!!! Say it with me now, "Gee, that's a neat concept. But I wonder what they've put in place to overcome a potential loss of power in one or more of the engines."
Click to expand...

Also interested if the 4000' ceiling is power limited, or includes reserve power to maintain some type of altitude after a motor failure...
 
SoonerAviator said:
Good gawd man, lrn 2 grammar, lol. You're worried about the failure of one motor out of 8? Do we have to bring out the old joke about the dreaded 7-engine approach in a B-52? I'm sure the other 7 motors can compensate for the loss of one, at least to get it on the ground without too much damage. Now a complete power failure would be the big issue, unless they have a way of simulating the rotor resistance of an autorotation. Then again, the chances of the power failure may be negligible, but that's a tough pill to swallow when your life is on the line.
Click to expand...

Instruction #1 PULL THE CHUTE! PULL THE CHUTE!

ElPaso Pilot said:
Also interested if the 4000' ceiling is power limited, or includes reserve power to maintain some type of altitude after a motor failure...
Click to expand...

Might I remind you: When the engine stops in your CessBonGrumiper you come down. There is no "altitude hold" at all.

I imagine they could lose 1 engine on each corner and still get down safe. After that refer to instruction # 1

It's just new and different and probably no worse than any helicopter already in service.
Cut them some slack
 
Shepherd said:
Instruction #1 PULL THE CHUTE! PULL THE CHUTE!



Might I remind you: When the engine stops in your CessBonGrumiper you come down. There is no "altitude hold" at all.
Click to expand...

We have learned that even a 777 will struggle to maintain altitude when fuel is exhausted...
 
Clark1961 said:
We have learned that even a 777 will struggle to maintain altitude when fuel is exhausted...
Click to expand...

There it is. I don't know why none of us has thought of this before.
All we need to prevent engine failures and crashes is have at least one member of the press on board.
Maybe we could keep them in a little box with a glass cover that we break, in case we run out of fuel.
 
Shepherd said:
Instruction #1 PULL THE CHUTE! PULL THE CHUTE!



Might I remind you: When the engine stops in your CessBonGrumiper you come down. There is no "altitude hold" at all.

I imagine they could lose 1 engine on each corner and still get down safe. After that refer to instruction # 1

It's just new and different and probably no worse than any helicopter already in service.
Cut them some slack
Click to expand...

Just trying to get my head around the specs. I was actually hoping that 4000' was a derated number.

But, this "LSA" helicopter has a gross weight greater than a R22 (1500 pounds vs. 1370), and is powered by a 0.6L engine indirectly coupled via 2 generators, vs. the 6L O360 in the R22.
 
Well, if this particular model is directed at being the "flying car" of the future, I don't know why it would need to go above 4,000' AGL. If that's an MSL figure, it's much more problematic unless you're always flying near sea-level with temps not getting too high. Normally service ceilings are in MSL, but who knows what they were quoting. I figure this is aimed at running 20-30 miles each way to work/shopping, and not likely getting much higher than 2K' AGL depending on airspace rules and obstacles.
 
SoonerAviator said:
Well, if this particular model is directed at being the "flying car" of the future, I don't know why it would need to go above 4,000' AGL. If that's an MSL figure, it's much more problematic unless you're always flying near sea-level with temps not getting too high. Normally service ceilings are in MSL, but who knows what they were quoting. I figure this is aimed at running 20-30 miles each way to work/shopping, and not likely getting much higher than 2K' AGL depending on airspace rules and obstacles.
Click to expand...

The airfoil only cares about density altitude, not AGL.

Density altitude right now in Phoenix is 4219', at 11:00 am. Airport elevation is 1135'. As you mentioned, this will be a coastal toy.
 
ElPaso Pilot said:
The airfoil only cares about density altitude, not AGL.

Density altitude right now in Phoenix is 4219', at 11:00 am. Airport elevation is 1135'. As you mentioned, this will be a coastal toy.
Click to expand...

Agreed, the only reason I questioned AGL/MSL is that the little tidbit of specifications doesn't allude to whether the ceiling is limited by airfoil or electronically limited by controller software. I could see them limiting the altitude ceiling if there was some concern about being able to safely return to ground under battery power, and being up at 10K AGL would require a >2K'/min descent which would exhaust the emergency batteries (5 min).
 
SoonerAviator said:
Agreed, the only reason I questioned AGL/MSL is that the little tidbit of specifications doesn't allude to whether the ceiling is limited by airfoil or electronically limited by controller software. I could see them limiting the altitude ceiling if there was some concern about being able to safely return to ground under battery power, and being up at 10K AGL would require a >2K'/min descent which would exhaust the emergency batteries (5 min).
Click to expand...
I'm thinking its a 68 hp, minus electric generating losses, minus 8 electric motor losses, minus 16 blades worth of prop losses, plus a 1500 pound gross weight physics limitation...
 
ElPaso Pilot said:
I'm thinking its a 68 hp, minus electric generating losses, minus 8 electric motor losses, minus 16 blades worth of prop losses, plus a 1500 pound gross weight physics limitation...
Click to expand...
... minus half of the props chopping through dirty airstreams.
 
Now what is going to happen to that chute as it passes through those three remaining spinning rotors? Hmm?
 
SoonerAviator said:
I'd think the same thing that happens when the Cirrus chute passes through the propeller . . .
Click to expand...
Even at the worst of times, it's unlikely that the spinning propeller on a cirrus would be behind the chute in the slipstream. It's virtually guaranteed on this contraption.
 
Salty said:
Even at the worst of times, it's unlikely that the spinning propeller on a cirrus would be behind the chute in the slipstream. It's virtually guaranteed on this contraption.
Click to expand...

I'm glad I'm not the only one with the same thought.
 
Pull the handle bend over and kiss your butt good by.
 
Well, lookie here. If this doesn't look like quite the interesting system -- not applicable to the OP topic, of course.

Clever use of zip ties that I hadn't considered on an airframe yet. o_O

 
ElPaso Pilot said:
Well, lookie here. If this doesn't look like quite the interesting system -- not applicable to the OP topic, of course.

Clever use of zip ties that I hadn't considered on an airframe yet. o_O

Click to expand...
What could go wrong?
 
Salty said:
Even at the worst of times, it's unlikely that the spinning propeller on a cirrus would be behind the chute in the slipstream. It's virtually guaranteed on this contraption.
Click to expand...
My comment was somewhat tongue-in-cheek. When you pull the CAPS in the Cirrus, it cuts fuel/power to the engine, right? This mostly negates much of the worry about the prop cutting through parachute cord. Entanglement is another issue. What would keep them from doing the same thing with this octocopter? Pull the chute, all power to rotors stops, and that pretty much removes most of the risk of having the rotors slicing-n-dicing parachute cord. In addition to that, I'd also think that they'd have a short length of abrasion-resistant cabling that would withstand any impact from a freewheeling rotor. I'm not saying this project ever gets off the ground (pun intended), but I sure think that even the most inept engineers could figure out a way to make it work with a fairly high success rate.
 
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