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Going over a cliff

Whilst I understand that the drone will not automatically change its altitude, is there some way to see (other than LOS) that the terrain is rising?

The M2P will actually change altitude if tracking in some formats, and certainly the OA system will (ok, should) stop it from hitting rising ground in front.
But, in the main drone pilots shouldn't depend on ANY automated features, and either watch the drone if close by, or (in my preference most flights) watch the device view when flying forward.

The danger is with a few exceptions (goggles / camera head tracking), your field of view is out front generally, if rolling to the left or right, or backing up, arcing shots etc, (this applies to the M2P >) you will have the OA sensors protection, but again dangerous to always rely on that.
Fine things like foliage free fine branches, wires etc are not generally picked up by OA.

In Australia, the GPS signal is rarely affected, even if close to obstacles, I've never had trouble getting GPS locks inside my home when checking systems / settings etc before a planned flight.
But do keep it in mind if descending into tight valleys / crevices etc, as rare as most of our flights will be in a most open setting.
 
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I hadn't thought of the reverse scenario, flying into a hill!
Are you saying that the drone will not sense land rising, assuming a gentle slope up, on the controller?
Whilst I understand that the drone will not automatically change its altitude, is there some way to see (other than LOS) that the terrain is rising?
This could be scarier than dropping off a cliff :)
The VPS can, on its own, make it fly up hill IF the drone is moving slowly enough, I have done it, but give it some welly and it will not react quickly enough, I HAVE NOT done that, I find other ways to crash.

There is another protection system that can make it climb, OA,
Obstacle Avoidance but you'd do best to read the manual about that, it can scare the doda out of you at times.
 
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The M2P will actually change altitude if tracking in some formats, and certainly the OA system will (ok, should) stop it from hitting rising ground in front.
But, in the main drone pilots shouldn't depend on ANY automated features, and either watch the drone if close by, or (in my preference most flights) watch the device view when flying forward.

The danger is with a few exceptions (goggles / camera head tracking), your field of view is out front generally, if rolling to the left or right, or backing up, arcing shots etc, (this applies to the M2P >) you will have the OA sensors protection, but again dangerous to always rely on that.
Fine things like foliage free fine branches, wires etc are not generally picked up by OA.

In Australia, the GPS signal is rarely affected, even if close to obstacles, I've never had trouble getting GPS locks inside my home when checking systems / settings etc before a planned flight.
But do keep it in mind if descending into tight valleys / crevices etc, as rare as most of our flights will be in a most open setting.
good stuff, thank you
 
The VPS can, on its own, make it fly up hill IF the drone is moving slowly enough, I have done it, but give it some welly and it will not react quickly enough, I HAVE NOT done that, I find other ways to crash.

There is another protection system that can make it climb, OA,
Obstacle Avoidance but you'd do best to read the manual about that, it can scare the doda out of you at times.
thank you, very helpful
 
People have reported "getting stuck" lik
To be honest the 5m height limit above a good VPS lock thing doesn't quite 'gel' with my recollection of at least one thread.
s it possible that the 30?m height limit. for no GPS AND no VPS. could be triggered from the height at which the drone lost GPS?
That would, I think, be a better fit with my recollection of the 'story'.
 
To be honest the 5m height limit above a good VPS lock thing doesn't quite 'gel' with my recollection of at least one thread.
s it possible that the 30?m height limit. for no GPS AND no VPS. could be triggered from the height at which the drone lost GPS?
That would, I think, be a better fit with my recollection of the 'story'.
This is a separate issue and not related to the OP's questions .... but
I've examined the data from three cases where the drone was flown into a canyon or similar environment where the skyview (and hence satellites) was blocked.
When the drone was lowered toward the bottom and came within VPS range, the drone was not able to climb more than 16 feet above the floor (or ledge) that VPS detected when the drone got close enough.

Here's the relevant section of a DJI manual:
Height is restricted to 16 ft (5 m) when the GPS signal is weak and Infrared Sensing System is operating.
Height is restricted to 98 ft (30 m) when the GPS signal is weak and Infrared Sensing System is not operating.

As you cannot disable VPS for any DJI Fly using drone, the second sentence is redundant.

It would appear to be dopey programming on DJI's part, but it's only a problem in very particular circumstances and not likely to affect most flyers.
 
This is a separate issue and not related to the OP's questions .... but
I've examined the data from three cases where the drone was flown into a canyon or similar environment where the skyview (and hence satellites) was blocked.
When the drone was lowered toward the bottom and came within VPS range, the drone was not able to climb more than 16 feet above the floor (or ledge) that VPS detected when the drone got close enough.

Here's the relevant section of a DJI manual:
Height is restricted to 16 ft (5 m) when the GPS signal is weak and Infrared Sensing System is operating.
Height is restricted to 98 ft (30 m) when the GPS signal is weak and Infrared Sensing System is not operating.

As you cannot disable VPS for any DJI Fly using drone, the second sentence is redundant.

It would appear to be dopey programming on DJI's part, but it's only a problem in very particular circumstances and not likely to affect most flyers.
Do you remember if one of the flights was in mountain country somewhere in continental North America and the guy saved the drone by flying it along the canyon to an area where the rim was just low enough for the drone to escape to the road side? By "just low enough" I mean there was only a few feet of clearance between the drone and the ground.
 
Do you remember if one of the flights was in mountain country somewhere in continental North America and the guy saved the drone by flying it along the canyon to an area where the rim was just low enough for the drone to escape to the road side? By "just low enough" I mean there was only a few feet of clearance between the drone and the ground.
That rings a bell.
But the others resulted in lost drones because there was no way to bring the drone up.
 
Do you remember if one of the flights was in mountain country somewhere in continental North America and the guy saved the drone by flying it along the canyon to an area where the rim was just low enough for the drone to escape to the road side? By "just low enough" I mean there was only a few feet of clearance between the drone and the ground.
If the ground slopes up in such a way that the drone can stay vertically within 5m of the sloping surface, then VPS won't prevent it flying like that up out of the canyon until it gets high enough to regain GPS signal.

But if the sides of the canyon are steeply vertical, then the drone will be prevented by the VPS from rising any higher than 5m from the bottom of whatever is visible to the VPS height sensors.
 
Here's the relevant section of a DJI manual:
Height is restricted to 16 ft (5 m) when the GPS signal is weak and Infrared Sensing System is operating.
That would be the one that applies when descending into a steep canyon and losing GPS reception, but having a solid VPS view of the canyon's floor. Then the VPS will prevent the drone rising higher than 5m from the canyon floor.

The intent there is, if you're flying indoors (or elsewhere) without GPS and relying on VPS to hold position, then DJI wants to prevent the drone ascending out of VPS range where you'd be left with only Atti mode, as though Atti is something to always be avoided.

Height is restricted to 98 ft (30 m) when the GPS signal is weak and Infrared Sensing System is not operating.
This one, I believe, is intended for, let's say, you're flying in circumstances with an unreliable GPS signal AND it's too dark for VPS to get a good positional fix. In that case DJI limits the height to 30m because they figure Atti mode in the dark at greater than 30m should be avoided?

I don't understand why they would combine weak GPS and Infrared Sensing though, since the GPS is for horizontal position hold, whereas the Infrared sensors are for height measurement. Shouldn't that refer to the Optical sensor instead, since that's the one used for horizontal position hold in the absence of GPS?

In any case, this second condition shouldn't come into play in the scenario of taking off and descending into a steep canyon, as the height measurement would be registered as a negative barometric height while descending into the canyon. If the GPS signal is weak AND the VPS system is not operating because it's too dark or not yet within range of the bottom of the canyon, then height would be limited to 98ft (30m) above the zero height registered at takeoff from the lip of the canyon's edge.
 
Maybe a lot of new flyers are as confused as I am.
I have a Mavic 2 Pro....I have the maximum altitude set to 400 feet. When the drone reaches 400 feet it stops climbing and issues a warning; "you have reached maximum altitude" and I happily fly around at 400'.
But what happens when I go over the edge, I am now at 1400 feet and, although there is no magnetic attraction, the drone is designed not to allow it to fly at that altitude, so what happens?


Maybe we are talking about different drones or I am really confused. My drone knows exactly how high it is, it feeds me that information instantly in real time as it is ascending or descending - it is visible on my controller and when I get too high or too low it warns me, isn't that the purpose of the sensors?


My concern is, if the drone is "locked" at a maximum altitude of 400 feet, it flies over a cliff and is now 1400 feet, will it descend to its maximum height restriction of 400 feet and if RTH is activated will it "force" itself to climb above the maximum set altitude.

What am I not getting?
It uses the distance from your point of launch which is typically darn close to your controller to calculate AGL.
 
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The drone calculates altitude relative to the altitude of its launch point. This means if you start on a hill you can fly greater than 400' AGL; if you launch from a valley you might hit the altitude limit at actual ground level.

The legal limits in your country are another matter, but the software limits are based on where you launch from.
Exactly. Not sure why folks don't read the owners manual. It explains this. Also just check out DJI's sites and their videos. Tons of pro shots and videos are in the mountains. One would think, "how are they able to do that legally."

It's because they are doing it legally. Read the manual. Better yet, just get some proper basic training. It's easy and cheap.
 
It uses the distance from your controller to calculate AGL.
Your drone doesn't do anything to calculate the height above ground level.
That's explained already in this thread.
If you think your drone is telling you the height above ground level, you should read through this thread and find some useful information.
 
Maybe a lot of new flyers are as confused as I am.
I have a Mavic 2 Pro....I have the maximum altitude set to 400 feet. When the drone reaches 400 feet it stops climbing and issues a warning; "you have reached maximum altitude" and I happily fly around at 400'.
But what happens when I go over the edge, I am now at 1400 feet and, although there is no magnetic attraction, the drone is designed not to allow it to fly at that altitude, so what happens?


Maybe we are talking about different drones or I am really confused. My drone knows exactly how high it is, it feeds me that information instantly in real time as it is ascending or descending - it is visible on my controller and when I get too high or too low it warns me, isn't that the purpose of the sensors?


My concern is, if the drone is "locked" at a maximum altitude of 400 feet, it flies over a cliff and is now 1400 feet, will it descend to its maximum height restriction of 400 feet and if RTH is activated will it "force" itself to climb above the maximum set altitude.

What am I not getting?
Take a part 107 course. This is easily explained. It's been explained above. I think everyone should get their part 107 if they are going to be flying. Great Intel to be learnt and just makes you a better UAV operator.

You have a good question, but for reals this would help you along with everyone else who has never taken it.
 
Your drone doesn't do anything to calculate the height above ground level.
That's explained already in this thread.
If you think your drone is telling you the height above ground level, you should read through this thread and find some useful information.
That's not what I was saying or meant, but thanks. No where did I say "drone" dude. Can you not read or do you just love to troll people with your 12,000+ comments. Most of which are argumentative in nature.
 
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That's not what I was saying or meant, but thanks.
Well your wording was very bad.
It (presumably your drone?) uses the distance from your controller to calculate AGL.
Distance from controller is unrelated to height.
Nothing is calculating your AGL height.
It's up to the flyer to estimate that for themselves.
 
Well your wording was very bad.
It (presumably your drone?) uses the distance from your controller to calculate AGL.
Distance from controller is unrelated to height.
Nothing is calculating your AGL height.
It's up to the flyer to estimate that for themselves.
Your words, go back to grade school and learn to read. You made up a crap load of assumptions based off your own insecurities and inability to read. Meta 4 quit trolling, the pure fact that the majority of your 12,000+ comment history shows that you get off arguing with people online.
 
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Would you kindly explain the above please because I too am completely baffled by what you are attempting to say.
Point of launch which is typically from where your remote is unless you're taking off from a launch pad else where. Or you're not flying VLOS. Pretty sure those commenting just want to troll and know exactly what I was saying.
 
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