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didnt hold home point

keat63

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I put the mavic pro up to film a sunset.
It was a bit breezy but within what i thought it's capibilities.
It handled altitude up to 50m OK.
However at maximum altutide of 120m the wind was obviously much stronger than it was at ground level, to the point that I could visbly see the mavic being blown away.
Reducing altitude and pushing forward on the stick and I brought her home without issue.

This made me think about the GPS capabilites.
Should it have maintained it's own GPS location, without any intervention from me ????
 
@keat63 GPS no matter how many Sats you have locked, can not overcome a wind that is to strong for the drone to handle
at the 400ft altitude you took it to, the wind would have been much much higher than the drone was capable of flying in ,it had nothing to do with GPS
if you had not descended ,and the drone had continued to be blown downwind ,then that would have been classed as pilot error
 
It’s that old accuracy vs precision thing. The GPS is very accurate: it accurately knows the drones position even if off the course you want. The drone‘s precision in flight is only as good as the conditions allow it to be.

Good for you in observing an issue and taking charge to correct it! So many “I flew my drone 4 miles out to sea with a tailwind and couldn’t get it back!” tales are based in inattention to conditions. You were watching what you were doing!
 
The Pro is rated at 40mph max speed so if the win d ws moire than that, it won't cope.
Well done for acting like a pilot@
 
A drone can fly "only so fast" with respect to the air, it changes its air speed by changing its tilt and the angle of tilt is software limited, thereby imposing the airspeed limit.
When the wind speed ( which is cited relative to the ground ) exceeds the drone's maximum air speed the drone can not hold its position relative to the ground.
As an aside, this behaviour is modified when flying downwind as less tilt is required to reach the maximum allowed GROUND speed i.e the tilt will be limited such that the maximum allowed ground speed is complied with (or nearly complied with lol). I have had a mavic mini RTH downwind in, or VERY near, the hover position. The reason being the wind speed was very near the RTH speed.

Two qualifications to the above,
1) assuming you were flying in one of the two slower modes, switching to sports mode might have increased the maximum allowable tilt and thereby the maximum air speed ( I am not sure how the MP is programmed I.e. if in one of the slow modes and so as to hold position in a strong wind, is its tilt limited to that of the slow mode or will it be allowed to tilt to the maximum of sports mode).
2) in some drones (thinking of the Minis) the maximum air speed is sometimes or always reduced when the gimbal is pointed down, I am not sure if this applies to the MP nor am I sure if it has been 'fixed' in the Minis.

Defens sorry but providing there is sufficient GPS for the drone to establish its position this partial flyaway has absolutely nothing to do with "accuracy vs position" it is simply that the drone was unable to fly up wind fast enough to maintain its position
 
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If you are asking whether the drone would automatically descend to hold horizontal position, then no. It tries to maintain its three dimensional position as best as it can, but as others have said, at some point can't overcome winds.
 
i have just read the OPs post again ,and i dont think that he is asking about different modes to fly against the wind
my reply was based purely on his assumption,that he thought that because it was in GPS mode, it would be able to hold its position ,regardless of the wind strength
yes that is what would normally happen if the drone had a GPS lock ,as apposed to going into Atti mode where it would drift with the wind
if my analogy is wrong then i apologise in advance
 
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This made me think about the GPS capabilites.
Should it have maintained it's own GPS location, without any intervention from me ????
Apart from the confusion about wind that's already been explained above, ....
Your drone doesn't attempt to stay at the home point.
Fly anywhere and take your hands of the sticks and the drone stays where it is and holds position. (if possible).
It doesn't return to the home point and hover there..
 
A drone can fly "only so fast" with respect to the air, it changes its air speed by changing its tilt and the angle of tilt is software limited, thereby imposing the airspeed limit.
When the wind speed ( which is cited relative to the ground ) exceeds the drone's maximum air speed the drone can not hold its position relative to the ground.
As an aside, this behaviour is modified when flying downwind as less tilt is required to reach the maximum allowed GROUND speed i.e the tilt will be limited such that the maximum allowed ground speed is complied with (or nearly complied with lol). I have had a mavic mini RTH downwind in, or VERY near, the hover position. The reason being the wind speed was very near the RTH speed.

Two qualifications to the above,
1) assuming you were flying in one of the two slower modes, switching to sports mode might have increased the maximum allowable tilt and thereby the maximum air speed ( I am not sure how the MP is programmed I.e. if in one of the slow modes will its tilt be limited to that of the slow mode or will it be allowed to tilt to the maximum of sports mode in order to hold position in a strong wind).
2) in some drones (thinking of the Minis) the maximum air speed is sometimes or always reduced when the gimbal is pointed down, I am not sure if this applies to the MP nor am I sure if it has been 'fixed' in the Minis.

Defens sorry but providing there is sufficient GPS for the drone to establish its position this partial flyaway has absolutely nothing to do with "accuracy vs position" it is simply that the drone was unable to fly up wind fast enough to maintain its position
Oh, I agree! Wind pushed the drone harder than it could resist to keep station. Just saying that the GPS can only tell the drone where it should be, not that it can hold that position.
 
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Keat63. I’m a bit confused. Your title states “didn’t hold home point”. The home point is recorded when the drone is started and there are enough GPS satellites acquired by the drone to record the home point. I’m thinking what you meant was that the drone was not holding position when no stick commands were given due to the strong upper winds. Which members have clarified in their posts.

And to Defens, Post #10, my understanding is that GPS does not tell the drone where it should be. It just gives you, via the controller, the drones location on the face of the earth and allows the drones software to hold position when no stick inputs are given, if sufficient satellites are locked onto by the drone.

I'm certainly open to any correction to my posts by fellow members.
Happy flying all.
 
Keat63. I’m a bit confused. Your title states “didn’t hold home point”. The home point is recorded when the drone is started and there are enough GPS satellites acquired by the drone to record the home point. I’m thinking what you meant was that the drone was not holding position when no stick commands were given due to the strong upper winds. Which members have clarified in their posts.

And to Defens, Post #10, my understanding is that GPS does not tell the drone where it should be. It just gives you, via the controller, the drones location on the face of the earth and allows the drones software to hold position when no stick inputs are given, if sufficient satellites are locked onto by the drone.

I'm certainly open to any correction to my posts by fellow members.
Happy flying all.
Oh good heavens - I’m getting sucked into one of these interminable semantics discussions! Fun Flyer, the GPS keeps track of position, just as you said. And if you are hovering in place, with no stick input, some combination of GPS and other firmware keeps the drone on station, as you also said. Now, in what way does the GPS NOT tell the drone where it should be when hovering?
 
Oh good heavens - I’m getting sucked into one of these interminable semantics discussions! Fun Flyer, the GPS keeps track of position, just as you said. And if you are hovering in place, with no stick input, some combination of GPS and other firmware keeps the drone on station, as you also said. Now, in what way does the GPS NOT tell the drone where it should be when hovering?
🤣🤣Defens. Yup. As stated interminable semantics. All in the interpretation of the GPS world and how it interacts with our wonderful drone technology. At the end of the day hope continues to provide us both with great drone experiences.
Love the technology when out flying my friends Cessna 177 Cardinal using ForeFlight on my iPad. So much useful information garnered from this technology.
 
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Apologies for the late response and any confusion in my question.

My basic understanding that it ought to have held it's gps location, so in effect fighting against the headwind.
Of course if the headwind was faster that the drone can fly, I assume it would lose ground, and get carried away.

What I ought to have done, is apply some stick input to see if it could cope with the headwind at such altitude.
Instead, I reduced altitude and then gave some stick input.
 

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