Possible ATTI problem

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I mainly fly in GPS mode but last night decided to give ATTI mode a try as i like the sound of filming whilst drifting there was no wind a very calm evening, i let the phantom hover in a stationary position then flipped the switch to ATTI mode and it began moving backwards on its own .Now I know its supposed to drift but i was under the impression it would drift in the position you moved. Every time i tried to fly forwards or left/right it kept trying to go backwards. Does it need a IMU calibration? In GPS it hovers perfectly no slight drift and it yaws without any drifting problems either, really not sure whats causing this?
 
It drifts with the wind. If it is a 15mph wind it will go off at 15mph by itself!
There is nearly always a bit of wind or even thermals. Higher you go more wind there is.
 
It drifts with the wind. If it is a 15mph wind it will go off at 15mph by itself!
There is nearly always a bit of wind or even thermals. Higher you go more wind there is.
This was hovering only 7 ft high no wind at all I still dont think it should be automatically drifting backwards
 
Do you have anything 3rd party installed on the bird that might change its center of gravity?
 
Inspect your props, even for the smallest chips/crack or try new pair. Just cause it feels calm it doesnt take much for atti to drift
 
I will try another set of props didnt think of that, but surely it would affect GPS mode as well if they were out!
 
I will try another set of props didnt think of that, but surely it would affect GPS mode as well if they were out!
Unless they are way out, you wouldn't even notice in GPS mode.
 
Unless they are way out, you wouldn't even notice in GPS mode.
ok will try a new set i have tonight see what the outcome is
 
In atti mode there is only altitude control and the phantom will always drift randomly even without wind due to the prop wash etc... The pilot always has to make corrections to maintain control. This is considered manual control and only the gyros are keeping it stable and level.

It amazes me how many people have no clue how to fly the phantom without GPS control! IE. Atti mode

Go out and buy a $100 quadcopter that has no GPS and learn to fly manually and become a real RC pilot, it will save your butt down the road and your $$$$ phantom investment.
 
In atti mode there is only altitude control and the phantom will always drift randomly even without wind due to the prop wash etc... The pilot always has to make corrections to maintain control. This is considered manual control and only the gyros are keeping it stable and level.

It amazes me how many people have no clue how to fly the phantom without GPS control! IE. Addi mode

Go out and buy a $100 quadcopter that has no GPS and learn to fly manually and become a real RC pilot, it will save your butt down the road and your $$$$ phantom investment.
Ive flown ATTI mode on my fc40 and p2v+ before so dont start judging me like an idoit after only your fourth post but havent flown it on my P3A, the reason i was asking for any help is because when i have used ATTI mode before the various phantoms havent behaved like that especially with no wind and any accelaration on my behalf, surely if your flying in one direction it shouldnt automatically try to fly in the opposite direction! As you must be a REAL rc pilot im sure you can explain the reason! Oh and by the way its not "addi" mode its actually ATTI mode.... i.e not GPS mode!
 
I mainly fly in GPS mode but last night decided to give ATTI mode a try as i like the sound of filming whilst drifting there was no wind a very calm evening, i let the phantom hover in a stationary position then flipped the switch to ATTI mode and it began moving backwards on its own .Now I know its supposed to drift but i was under the impression it would drift in the position you moved. Every time i tried to fly forwards or left/right it kept trying to go backwards. Does it need a IMU calibration? In GPS it hovers perfectly no slight drift and it yaws without any drifting problems either, really not sure whats causing this?
I fly very often in ATTI mode since I find it much less boring. What you described seems to be perfectly normal for ATTI mode. I find it most stable at about 10 feet, but never really stationery. As I get higher, it becomes less stable for obvious reasons. Under 10 feet, especially under 5 feet, it becomes quite interesting.
 
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I fly very often in ATTI mode I find it much less boring. What you described seems to be perfectly normal for ATTI mode. I find it most stable at about 10 feet, but never really stationery. As I get higher, it becomes less stable for obvious reasons. Under 10 feet, especially under 5 feet, it becomes quite interesting.
when i have flown ATTI with past phantoms they were normally higher up, i was only trying something when i had it low and thought it was slightly odd behaviour, thanks for your help.
 
It drifts with the wind. If it is a 15mph wind it will go off at 15mph by itself!
There is nearly always a bit of wind or even thermals. Higher you go more wind there is.

not correct.
wind speed and p3 speed are correlated to the aerodynamics of the p3...
a plastic bag and a supersonic delta wing will have have different speeds at 15 mph winds hitting.

so the p3 comes somehow in between and i would say 10-12 mph..
 
When in question, yaw the phantom 45 degrees and turn ur body the same direction. If it still drifts back towords you, younhave a ship problem, if it drifts side to side, its the wind.
 
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I fly very often in ATTI mode since I find it much less boring. What you described seems to be perfectly normal for ATTI mode. I find it most stable at about 10 feet, but never really stationery. As I get higher, it becomes less stable for obvious reasons. Under 10 feet, especially under 5 feet, it becomes quite interesting.
Below 10' is very sketchy when trying to land. It drifts at a higher rate of speed in the final 5' in my case. I often try to catch it at 6' or so.
 
Below 10' is very sketchy when trying to land. It drifts at a higher rate of speed in the final 5' in my case. I often try to catch it at 6' or so.
I am not brave enough to hand catch in ATTI mode. I'll fly it relatively close to my location, then switch modes for the hand catch itself.
 
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I am not brave enough to hand catch in ATTI mode. I'll fly it relatively close to my location, then switch modes for the hand catch itself.

Yeah I think if I were forced to land in ATTI, I'd just put her down on her own. Otherwise if GPS were an option, it's hand catch all the way.
 
not correct.
wind speed and p3 speed are correlated to the aerodynamics of the p3...
a plastic bag and a supersonic delta wing will have have different speeds at 15 mph winds hitting.

so the p3 comes somehow in between and i would say 10-12 mph..

Not if the wing is at right angles to the flow!
This is pretty obvious I was speaking generally,,,,,
 

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