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Max ceiling??

#1
Anyone know the max ceiling of a multirotor? I want to take a tricopter up to Mt. Fuji. The the mountain tops at 12,300ft and I assume that's asl. Anyone took a mulitrotor up a mountain anywhere or the highest altitude?
 

PHugger

Church Meal Expert
#2
I listen to a photography podcast - Tips From The Top Floor with Chris Marquardt
He runs a Photography workshop in the Himalayan mountains fairly regularly.
One of his partners on the trek is a videographer named Jon Miller.
The last trek Jon took a Multirotor with him.

Here is some video from the 2014 trek -

Here is some BTS video from Jon's site about his 'drone' a TurboAce Matrix E quadcopter -

Base camp on Everest is over 17,000 ft.
So - I would guess you would be OK as long as you are allowed to fly in Japan.





PCH
 

PHugger

Church Meal Expert
#5
The lack of air at altitude is a problem. Propeller driven aircraft during WWII had a hard ceiling above which they could not fly. To gain an advantage the super charger was developed. It compresses the air entering the engine and allowed them to fly higher. It also boosted their performance and they had more power. Look up the history of the Corsair, Hellcat or Mustang. The thinner the air, the less effective the propellers will be. Eventually your multirotor will climb until the thrust diminishes to the point where it can only support it's weight and no higher.


PCH
 

Cyberdactyl

Misfit Multirotor Monkey
#6
Exactly right.

And that's why in the movie "Red Planet" when AMEE, the robot that lands with the crew, releases her "drone", it is basically a physics blooper.

The Martian atmosphere at ground level is roughly equal in density to earth's at 110,000 feet. Absolutely impossible for a multirotor to fly with any mass at all.
 
#7
Exactly right.

And that's why in the movie "Red Planet" when AMEE, the robot that lands with the crew, releases her "drone", it is basically a physics blooper.

The Martian atmosphere at ground level is roughly equal in density to earth's at 110,000 feet. Absolutely impossible for a multirotor to fly with any mass at all.
But in the movie, there was oxygen provided by the algae and the little alien bugs if I remember right . The density could have become similar to earths. Those Everest videos were amazing. He was using a quad with 15in props. I'm at a disadvantage. I'm running 1450kv suppo motors with 22a ipeaka ESC's rotating 8x4.3 props. Is the bat bone a good platform to upgrade? The climbing season isn't till July so I have some time.
 

Craftydan

Hostage Taker of Quads
Moderator
Mentor
#8
. . . not to mention the 0.006 Standard Atmosphere pressure would be unbreathable, even if it had plenty of bug made O2. Heck, plant's can't even use the CO2 because the whole transpiration process won't work at those pressures -- it's so thin it suffocates plants . . . and makes parachutes inadequate, which is why we use rocket platforms and airbags. Nope -- rotorcraft are worthless there, but Mt Fuji? piece of cake ;)
 

Cyberdactyl

Misfit Multirotor Monkey
#9
But in the movie, there was oxygen provided by the algae and the little alien bugs if I remember right . The density could have become similar to earths.
I'm not sure how it would be possible for an organism on the planet to raise the density of the atmosphere to such an extent to allow AMEE's copter to fly, and not be noticed in the span of a few years. As CD said, sure the O2 percentage might have risen, but the energy involved to raise the atmospheric pressure from converting a solid or liquid to fly a copter would have been teraformingly staggering, well beyond even the most liberal conjecture.

But the critical disconnect was the copter was designed for the Martian atmosphere as they were expecting it.
 
#10
Yeah true, it's been a few years since I seen the movie. I couldn't remember of the time frame. Atmospheric conditions and development ain't my strong suit so I'll let y'all have this one haha. Charged a couple batteries and did a few test flights in the cold to fine tune everything. In a full throttle climb the left boom dips. I'm going into the mixer setting and lowering the throttle on channel 2 while channel 1 is 127. Still dips a bit though. I wonder if cg could be the problem Everything else is great though. It's not a huge problem. So I'm not too worried about it. Slowly gonna start getting FPV gear.
 

Craftydan

Hostage Taker of Quads
Moderator
Mentor
#11
Can you lift the boom by control while at WOT? If you can, it's probably more ESC lag than imbalanced power.

I've seen a boom dip on a throttle punch get fixed with upgraded ESCs -- are you running Flashed ESCs? That's one of the more obvious performance improvements everybody talks about.

It's also possible it could be a vibe effect -- Punch the throttle and the increased vibe from that motor is throwing off the gyro readings causing the board to slow that motor -- could also be on the opposing motor, but if it's vibe it would be acting on that axis.
 

cranialrectosis

Faster than a speeding faceplant!
Mentor
#13
Dan is right. The dipped boom can be a sign of a struggling motor.

Did you synch ESCs (all motors start at the same time)?

When you stop the rotors does the motor on the boom that dips stop first?

Does the motor on the boom that dips get hotter than the other motors when you fly? Does the ESC?

Before you add weight and stress to the copter with FPV gear, you want to know if that motor is having issues. :)