Problem on take-off

Roaddogg · May 22, 2016

After flying several locations with my P3P today with no problems ... Towards the end of the day, every time I took off it seemed to pull really bad and not hover well. Any suggestions? Thanks.

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konidair · May 23, 2016

Have you tried to upload your logs on Healthydrones and look for errors(or better post it here)?

Roaddogg · May 23, 2016

Very new flyer and not sure how to upload to healthydrones or here... Sorry, I have no experience with these procedures (I probably should learn this).

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konidair · May 23, 2016

It's ok to be new, I consider myself a new flyer too

I learnt about Healthydrones from this forum and I believe uploading the flight log should be the first thing to do when troubleshooting drone issues. Depending on the hardware and software you use there a few different ways for uploading your flight logs but don't worry, it's all explained here: HealthyDrones.com - Innovative flight data analysis that matters

FantomFlier · May 23, 2016

Roaddogg said:
After flying several locations with my P3P today with no problems ... Towards the end of the day, every time I took off it seemed to pull really bad and not hover well. Any suggestions? Thanks.

You need to provide a bit more information - describe what you mean by "pull really bad" and "not hovering well". What are the symptoms?

An observation: One thing which may be affected by "several locations" is the compass, which in turn could affect hover stability.

Roaddogg · May 23, 2016

Thanks for the replies. The first problem I noticed was that the bird drifted hard to the left right after auto takeoff. I shut her down and when I tried again it was a bit better but was drifting towards me. After I got it up I noticed that it seemed to be pulling to the left a bit and I was fighting with it to keep it stable. After that I changed locations and did a quick test and after takeoff it was again drifting towards me. FYI - I do believe that I got a quick message saying something like ... compass problem - move to another spot (which I did and got a safe to fly).

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Kima kim · May 23, 2016

Roaddogg said:
Thanks for the replies. The first problem I noticed was that the bird drifted hard to the left right after auto takeoff. I shut her down and when I tried again it was a bit better but was drifting towards me. After I got it up I noticed that it seemed to be pulling to the left a bit and I was fighting with it to keep it stable. After that I changed locations and did a quick test and after takeoff it was again drifting towards me. FYI - I do believe that I got a quick message saying something like ... compass problem - move to another spot (which I did and got a safe to fly).

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I guess you need to calibrate the compass before you fly it on it's maiden flight and from every other new location.

Mimoid · May 23, 2016

1) Compass calibration? Read up on how and when to do this. I would think that this is the main cause for the issue you are experiencing,

2) Wind? Sometimes wind gusts can make the Phantom struggle really hard to stay in one place, specially if you are hovering low.

3) Satellite locks? You are not accidentally flying in Atti mode, are you? Make sure that you have at least 8-9 satellites, the screen says something like "P-GPS Safe to fly", and the indicators on the aircraft are blinking slowly in green.

//Tom

Mimoid · May 23, 2016

Kima kim said:
I guess you need to calibrate the compass before you fly it on it's maiden flight and from every other new location.

Do not recalibrate on every new location. If you once have achieved a good and solid calibration, there is absolutely no need to calibrate the aircraft again (unless you have travelled really far, like 100 km or more).

Quite the contrary, a compass calibration should be approached with the uttermost caution - it should not be done unless absolutely necessary, and should always be followed by a dedicated and strictly controlled test flight afterwards. I would think that the majority of the reported flyaways with the P3 can be attributed to incorrectly performed compass calibrations.

//Tom

msinger · May 23, 2016

Roaddogg said:
Very new flyer and not sure how to upload to healthydrones or here... Sorry, I have no experience with these procedures (I probably should learn this).

You'll see more information in your log if you upload it to my log viewer instead.

SteveAikens · May 23, 2016

What is "cell deviation" and what does it mean?

CCDD · May 23, 2016

I just went through a very similar issue on a "brand new" replacement P3P from DJI. Ended up having to send it back for a replacement again and finally, all is set. Not matter where I attempted to fly. it was going left right after takeoff and had to immeidately land to avoid a catastrophe. No compass calibration or IMU cal. did anything to alleviate issue.

Mimoid · May 23, 2016

SteveAikens said:
What is "cell deviation" and what does it mean?

It's abnormalities in the battery cells (there are four cells in the Phantom Intelligent Battery). Minor deviations may be appearing already from start and will be increasing with age. They are quite normal. Major deviations should not occur.

//Tom

Roaddogg · May 23, 2016

Thanks for the good info... I will upload the flight log sometime tonight. I have one more question... Is it safe to do calibrations (IMU, Compass, and Gimbal, or for that matter firmware updates) with the PolarPro filter? Man, I'm getting paranoid!!

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Mimoid · May 23, 2016

CCDD said:
I just went through a very similar issue on a "brand new" replacement P3P from DJI. Ended up having to send it back for a replacement again and finally, all is set. Not matter where I attempted to fly. it was going left right after takeoff and had to immeidately land to avoid a catastrophe. No compass calibration or IMU cal. did anything to alleviate issue.

Yes, could have been a defect in the motors, the FC, or the sensors. Not easy to know... But the main thing is that it is fixed!

Roaddogg said:
Thanks for the good info... I will upload the flight log sometime tonight. I have one more question... Is it safe to do calibrations (IMU, Compass, and Gimbal, or for that matter firmware updates) with the PolarPro filter? Man, I'm getting paranoid!!

Sent from my iPod touch using PhantomPilots mobile app

Filters should not be a problem, but make sure that the Phantom is as level as possible during IMU and gimbal calibration. I usually remove the propellers, place a glass pane on the propeller shafts (from an IKEA picture frame) and use a spirit level on this glass pane to make sure that the Phantom is completely horizontal in each direction. If there is a slight tilt, I just put pieces of paper under the landing gears to level them out.

Also, try to make sure not to have a too high ambient air temperature while doing the IMU calibration, otherwise the Phantom will need to warm up to that temperature on consecutive startups for the self-checks, which might take a lot of time. You really don't have to put the Phantom into the freezer, just strive for roughly the same ambient air temperature as what will be normal for your flying.

//Tom

SteveAikens · May 23, 2016

Mimoid said:
It's abnormalities in the battery cells (there are four cells in the Phantom Intelligent Battery). Minor deviations may be appearing already from start and will be increasing with age. They are quite normal. Major deviations should not occur.

//Tom

Thanks Tom. It appears it's not a real concern in my case. I have a few [red] deviations shown in the report but then they go on just fine. Interesting.