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I don't doubt a quad copter could hit 10k feet, but I do doubt many people would go that high. The only way to control that would be via a remote telemetry and/

I don't doubt a quad copter could hit 10k feet, but I do doubt many people would go that high. The only way to control that would be via a remote telemetry and/or video link or via strict autonomous programming. A standard 250 class quad could likely hit that 3km in 1.5-3 minutes under full power. I know from my time build and flying that a flight time for a quad hovered (hah) around 15-20 minutes on average. That leaves 9-12 minutes of loiter time as max. Then you need to factor in the power cost of stabilizing the aircraft at the height. The wind will be shoving it around so the FC will need to be constantly fighting for position hold. I'd really love to see the math on the probability of a tiny quad intersecting the flight path of a firefighting aircraft at 3km altitude though. They are small and that's a LOT of open space. I can barely spot one against the open sky at a few hundred feet up. If these guys spotted one they must have amazing superhuman vision or amazing luck to have come within a very close distance. Personally I put most of the sightings into the mass-hysteria camp. I know there are idiots out there flying in controlled space, but I also think things are being blown way out of proportion. Edit: I found a site that did the speed/climd rate calculations. My numbers are bit off. The DJI, a common platform, could hit 3km in about 5.5 minutes and a 250 racing quad could do it in about 5. With about 20 minutes of battery power that leaves maybe 5-10 minutes of loiter time. DJI Phantom 2 Vision+: flight speed of 17 m/s (61 km/h) and a maximum climbing rate of 9 m/s 250 FPV Racing Quad: maximum flight speed of 18.5 m/s (67 km/h) and a maximum climbing rate of 10 m/s source: http://bpmsg.com/flight-speed-of-a-quadcopter/ http://bpmsg.com/flight-speed-of-a-quadcopter/

fnordfnordfnord 11y ago
10,000 ft has to be above or near the "service ceiling" of what a quad copter is even capable of. As altitude increases, air density decreases. The copter will have to work very hard, and will have less control force available. I think you're over-estimating the available power of a quad copter. I think it's a certainty that one would/should have a video system for operating without line-of-sight. Video systems are common in high-end equipment. >Personally I put most of the sightings into the mass-hysteria camp. I know there are idiots out there flying in controlled space, but I also think things are being blown way out of proportion. Yeah. Agreed. >>I found a site that did the speed/climd rate calculations. My numbers are bit off. The DJI, a common platform, could hit 3km in about 5.5 minutes and a 250 racing quad could do it in about 5. With about 20 minutes of battery power that leaves maybe 5-10 minutes of loiter time. 10,000 ft seems right at the edge of what the things can even do. They aren't going to be stable or easy to fly/land like a fixed wing aircraft would. edit: forgot part of my post. >I'd really love to see the math on the probability of a tiny quad intersecting the flight path of a firefighting aircraft at 3km altitude though. They are small and that's a LOT of open space. "Big Sky" theory doesn't give me as much comfort as it ought to. >I can barely spot one against the open sky at a few hundred feet up. If these guys spotted one they must have amazing superhuman vision or amazing luck to have come within a very close distance. This. I have a difficult time spotting full-sized aircraft in the air, and I have pretty good vision.
- votingprawn 11y ago
  > 10,000 ft has to be above or near the "service ceiling" of what a quad copter is even capable of. As altitude increases, air density decreases. Its "only" a 25% reduction in density, you can still get a fair amount of flying done at that altitude. My colleagues have been to Ecuador twice for field work and had no issues flying quads in Quito (9,300ft), no need to change control gains or anything like that. So I know its perfectly possible.
zobzu 11y ago
250mm quads fly 3-7mins and going straight up is not hovering, it takes a lot of power. I fear you dont know what you're talking about. Basically you can go 3k up then stay a minute and free fall down. Bigger quads can fly longer - albeit going up always takes most energy and many big quads also need energy to go down / can't free fall without crash
- lsaferite 11y ago
  Don't know about you, but I regularly got 15 minute flight times on my quads, so yes, I do know what I'm talking about.
  - zobzu 11y ago
    Dilated time bubble i guess!

fnordfnordfnord 11y ago

10,000 ft has to be above or near the "service ceiling" of what a quad copter is even capable of. As altitude increases, air density decreases. The copter will have to work very hard, and will have less control force available. I think you're over-estimating the available power of a quad copter. I think it's a certainty that one would/should have a video system for operating without line-of-sight. Video systems are common in high-end equipment. >Personally I put most of the sightings into the mass-hysteria camp. I know there are idiots out there flying in controlled space, but I also think things are being blown way out of proportion. Yeah. Agreed. >>I found a site that did the speed/climd rate calculations. My numbers are bit off. The DJI, a common platform, could hit 3km in about 5.5 minutes and a 250 racing quad could do it in about 5. With about 20 minutes of battery power that leaves maybe 5-10 minutes of loiter time. 10,000 ft seems right at the edge of what the things can even do. They aren't going to be stable or easy to fly/land like a fixed wing aircraft would. edit: forgot part of my post. >I'd really love to see the math on the probability of a tiny quad intersecting the flight path of a firefighting aircraft at 3km altitude though. They are small and that's a LOT of open space. "Big Sky" theory doesn't give me as much comfort as it ought to. >I can barely spot one against the open sky at a few hundred feet up. If these guys spotted one they must have amazing superhuman vision or amazing luck to have come within a very close distance. This. I have a difficult time spotting full-sized aircraft in the air, and I have pretty good vision.

votingprawn 11y ago
> 10,000 ft has to be above or near the "service ceiling" of what a quad copter is even capable of. As altitude increases, air density decreases. Its "only" a 25% reduction in density, you can still get a fair amount of flying done at that altitude. My colleagues have been to Ecuador twice for field work and had no issues flying quads in Quito (9,300ft), no need to change control gains or anything like that. So I know its perfectly possible.

zobzu 11y ago

250mm quads fly 3-7mins and going straight up is not hovering, it takes a lot of power. I fear you dont know what you're talking about. Basically you can go 3k up then stay a minute and free fall down. Bigger quads can fly longer - albeit going up always takes most energy and many big quads also need energy to go down / can't free fall without crash

lsaferite 11y ago
Don't know about you, but I regularly got 15 minute flight times on my quads, so yes, I do know what I'm talking about.
- zobzu 11y ago
  Dilated time bubble i guess!