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High altitude rotors at sea level

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Hi all

I was just wondering if anyone has tried the High altitude rotors at sea level and what difference does it make?

Is it just a matter of more lift or is there more speed as well? How does this affect the stability of the filming?

Thanks

Keith
 
Hi all

I was just wondering if anyone has tried the High altitude rotors at sea level and what difference does it make?

Is it just a matter of more lift or is there more speed as well? How does this affect the stability of the filming?

Thanks

Keith
Don't do it is the simple answer.
This has been discussed previously (there are threads already pondering the same question)
Please see my post #4 in this thread......
High altitude 1360x prop question FINALLY answered...
 
Great thanks
Jump over to the post @The Editor linked - the advice of "just don't do it" isn't exactly evidence based. I posted a response over there so have a read. Use at your own discretion, but DJI GO should be giving you any warnings if there were any issues so until then keep an open mind.
 
I tried last week. I got a warning message from dji go 4, "Propeller error ..." followed by a warning "Do not use Plateau Propellers at low altitude".

I guess, the propeller for high altitude can cause overload to the motors and escs due to their pitch create more load at same rpm. As long as you do not push the trottle up too high, it is safe. But we do not know how far the trottle go that will start damage to motors and escs.
 
I tried last week. I got a warning message from dji go 4, "Propeller error ..." followed by a warning "Do not use Plateau Propellers at low altitude".

I guess, the propeller for high altitude can cause overload to the motors and escs due to their pitch create more load at same rpm. As long as you do not push the trottle up too high, it is safe. But we do not know how far the trottle go that will start damage to motors and escs.
Brilliant - that's exactly what you'd hope for in the event they caused issues. Would you mind posting a screenshot next time you get the chance? I take it the notification is one of the in-flight pop-up's in the top left of the screen? I haven't found a single person whose actually reported that error before so it's good to know.
 
The Dji's products are improved in many ways, though not perfect yet. The previous I1 may not contain sensor or part of firmware to detect the type of propeller mounting. So no one reports the error.
 
The Dji's products are improved in many ways, though not perfect yet. The previous I1 may not contain sensor or part of firmware to detect the type of propeller mounting. So no one reports the error.

It's actually easy for the I1 to figure it out. All the controllers does is look at the current draw barometric pressure and the gps altitude and it compares it to what it expects to be running.
 
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The Dji's products are improved in many ways, though not perfect yet. The previous I1 may not contain sensor or part of firmware to detect the type of propeller mounting. So no one reports the error.
It's an interesting theory. It must be able to detect the RPM/current change and knows environmental conditions to produce that performance are't realistic - ie the air can get considerably thinner than at sea level (via elevation) but not denser. Aside from that it would have absolutely no idea what propeller you put on it. It's a real shame the DJI tech guys are so useless, it would be nice to have clarity on it.
 
It's actually easy for the I1 to figure it out. All the controllers does is look at the current draw and the gps altitude and it compares it to what it expects to be running.
I find the fact it automatically assumes the propellers have been swapped to be the most interesting part because it can;t actually know they have been swapped. There's no sensor dedicated to identifying the props.

And there weren't "motor overloaded" errors or anything else like that to suggest it was actually causing issues, so the propeller notification seems neither here nor there. It's just telling you it knows you're up to something haha.
 
It's an interesting theory. It must be able to detect the RPM/current change and knows environmental conditions to produce that performance are't realistic - ie the air can get considerably thinner than at sea level (via elevation) but not denser. Aside from that it would have absolutely no idea what propeller you put on it. It's a real shame the DJI tech guys are so useless, it would be nice to have clarity on it.

actually sea level air can get denser. The highest ever recorded atmospheric pressure was 32in/hg at an 850ft elevation which corresponds to a altitude of 2000+ Feet BELOW sea level. The Motor Overload warning is based on current consumption plotted against the IMU's speed/acceleration output. So yes it's easy for the flight control system to figure out what props are on it
 
actually sea level air can get denser. The highest ever recorded atmospheric pressure was 32in/hg at an 850ft elevation which corresponds to a altitude of 2000+ Feet BELOW sea level. The Motor Overload warning is based on current consumption plotted against the IMU's speed/acceleration output. So yes it's easy for the flight control system to figure out what props are on it
Googling "highest recorded barometric pressure" and posting it doesn't justify you're argument in any way. It actually proves mine - what's to say you aren't flying in those ridiculous conditions instead of swapping the props? The copter can't differentiate that.
 
actually sea level air can get denser. The highest ever recorded atmospheric pressure was 32in/hg at an 850ft elevation which corresponds to a altitude of 2000+ Feet BELOW sea level. The Motor Overload warning is based on current consumption plotted against the IMU's speed/acceleration output. So yes it's easy for the flight control system to figure out what props are on it
And 2000 feet is hardly anything. High altitude props are for use at 2500-5000 metres.

Also, why would the "Motor Overloaded" warning have any correlation to IMU/gyro information? It doesn't really matter what the aircraft is doing so much as what each individual motor is doing. The way to aleviate overloaded motors is to power them down and invariably the copter will slow down, but the issue actually has nothing to do with speed or attitude.
 
Googling "highest recorded barometric pressure" and posting it doesn't justify you're argument in any way. It actually proves mine - what's to say you aren't flying in those ridiculous conditions instead of swapping the props? The copter can't differentiate that.

No need to google that, and ridiculous condition? a winter day in death valley has a density altitude of 1,200 to 1,800 feet below sea level and yes I've flown both my I1 and my full size plane in those conditions

As for the I1 differentiating what prop is on it. Why wouldn't it, all the info is there in the flight control package, it's just math and it's free. The simple fact that it reports "Motor Overload" means it's calculating instantaneous torque which it would have to do to calculate the RTH point due to battery capacity
 
And 2000 feet is hardly anything. High altitude props are for use at 2500-5000 metres.

Also, why would the "Motor Overloaded" warning have any correlation to IMU/gyro information? It doesn't really matter what the aircraft is doing so much as what each individual motor is doing. The way to aleviate overloaded motors is to power them down and invariably the copter will slow down, but the issue actually has nothing to do with speed or attitude.


You are missing the point and not understanding what it's calculating for flight performance. It totally matters what the aircraft is doing for their control law to work.
 
You are missing the point and not understanding what it's calculating for flight performance. It totally matters what the aircraft is doing for their control law to work.
Nup - you're missing the point that it has minimal to do with literal control of the copter. It's obviously important for the FC to know all those parameters as it flies itself, but it doesn't directly have any bearing on triggering a motor overloaded error. Flying straight up at full throttle can trigger it just the same as flying flat stick pitch can - it's all about throughput and not attitude.
 
Nup - you're missing the point that it has minimal to do with literal control of the copter. It's obviously important for the FC to know all those parameters as it flies itself, but it doesn't directly have any bearing on triggering a motor overloaded error. Flying straight up at full throttle can trigger it just the same as flying flat stick pitch can - it's all about throughput and not attitude.

I never said it was about altitude, I said it was about Current vs calculated performance
 
I never said it was about altitude, I said it was about Current vs calculated performance
The Motor Overload warning is based on current consumption plotted against the IMU's speed/acceleration output.

Speed and attitude are inherently linked on a copter. But just because they are a means of inducing power output through the motors doesn't mean an overloaded motor has anything to do with them. An overloaded motor doesn't discriminate over what state of the copter is in - if it's pulling to much current it's pulling too much current.
 
No need to google that, and ridiculous condition? a winter day in death valley has a density altitude of 1,200 to 1,800 feet below sea level and yes I've flown both my I1 and my full size plane in those conditions

As for the I1 differentiating what prop is on it. Why wouldn't it, all the info is there in the flight control package, it's just math and it's free. The simple fact that it reports "Motor Overload" means it's calculating instantaneous torque which it would have to do to calculate the RTH point due to battery capacity
Again, citing one specific fact about one specific place and comparing it to one other specific location that you happen to fly doesn't make the two of those things universal facts.

The point is how can it differentiate between environmental conditions and a change in prop? Those two variables have the same affect on power output of the motors and subsequent flight performance, but according to you it just knows which is which?
 

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