When i saw the first video for this helicopter some time back the pilot barely left the ground and there were concerns over the emergency parachute if there were problems with the engines
basically an explosive charge would fire the parachute up above the blades, but at the time there were worries over reliability.
with this video the stability seems to have been sorted out allowing the pilot to gain some pretty impressive height, although without that safety net of the shute I wouldn't want to go very high.
...without that safety net of the chute I wouldn't want to go very high.
Provided you have the altitude to set it up, a 'normal' helicopter is capable of safe power-off landing via autorotation. Don't know whether that applies to a simple weight-shift coaxial helicopter like this. It certainly would be disconcerting to fly this craft without some sort of plan B. (With paragliding, a reserve makes all the difference wrt enjoyment, especially in turbulent thermic conditions.)
I remember watching a film of the flight test of the OH-6 to determine the deadman's curve. On the last test the helicopter rolled like a ball, the blades flew off and the tail boom broke off. The test pilot climed out uninjured because the fuselage remained intact. Not much (any) protection on this bird.
Provided you have the altitude to set it up, a 'normal' helicopter is capable of safe power-off landing via autorotation. Don't know whether that applies to a simple weight-shift coaxial helicopter like this.
It looks like the blades are fixed pitch - which would mean no autorotation.
Not only are they fixed pitch, which makes autorotation impossible(you can't 'reverse pitch' to gain rotorspeed during the first part of the descent), but this is also a counter-rotating design, which introduces new problems...
A gearbox failure may cause the rotors to no longer rotate at speeds to counter the other's torque, sending the machine into an uncontrolled spin.
(counter-rotating gearboxes like this one are complex since they need to vary the torque of the props to rotate the machine if the pilot wants to face another way)
Unless that thing has a very good chute system, I'd consider it suicide to fly it.
Not only are they fixed pitch, which makes autorotation impossible(you can't 'reverse pitch' to gain rotorspeed during the first part of the descent), but this is also a counter-rotating design, which introduces new problems...
A gearbox failure may cause the rotors to no longer rotate at speeds to counter the other's torque, sending the machine into an uncontrolled spin.
(counter-rotating gearboxes like this one are complex since they need to vary the torque of the props to rotate the machine if the pilot wants to face another way)
Unless that thing has a very good chute system, I'd consider it suicide to fly it.
Ron Czapala
Posts: 2,418
Comments
basically an explosive charge would fire the parachute up above the blades, but at the time there were worries over reliability.
with this video the stability seems to have been sorted out allowing the pilot to gain some pretty impressive height, although without that safety net of the shute I wouldn't want to go very high.
Provided you have the altitude to set it up, a 'normal' helicopter is capable of safe power-off landing via autorotation. Don't know whether that applies to a simple weight-shift coaxial helicopter like this. It certainly would be disconcerting to fly this craft without some sort of plan B. (With paragliding, a reserve makes all the difference wrt enjoyment, especially in turbulent thermic conditions.)
John Abshier
It looks like the blades are fixed pitch - which would mean no autorotation.
A gearbox failure may cause the rotors to no longer rotate at speeds to counter the other's torque, sending the machine into an uncontrolled spin.
(counter-rotating gearboxes like this one are complex since they need to vary the torque of the props to rotate the machine if the pilot wants to face another way)
Unless that thing has a very good chute system, I'd consider it suicide to fly it.
A gearbox failure may cause the rotors to no longer rotate at speeds to counter the other's torque, sending the machine into an uncontrolled spin.
(counter-rotating gearboxes like this one are complex since they need to vary the torque of the props to rotate the machine if the pilot wants to face another way)
Unless that thing has a very good chute system, I'd consider it suicide to fly it.