Welcome to PhantomPilots.com

Sign up for a weekly email of the latest drone news & information

Phantom went crazy on GPS flight mode

Discussion in 'General Discussion' started by Miika, Aug 31, 2013.

  1. Miika

    Joined:
    Aug 31, 2013
    Messages:
    221
    Likes Received:
    1
    Location:
    Helsinki, Finland
    I'm not sure what happened today, but on two of my flights using GPS MODE the Phantom went crazy.

    I got really good GPS before I started the flight (0 red blinks). I'm beginner so I decided to stay with the GPS mode.

    After around 6 minutes of perfect flying (Phantom responded as it should in GPS mode) and then Phantom just went bezerk. Started climbing and moving into a direction it wasnt supposed to, because I had all the controls in the neutral. As it started to come down it moved very fast and took a curve before going down to bushes. It's not a problem if you can keep the Phantom in the air above obstacles (trees etc). But the problem was that the it came down by itself and by all means it wasnt a landing type of situation.

    The same thing happened twice, even when I had a good GPS. I'm pretty freaked about this incident, because I dont want to destroy my Phantom.

    Any comments on this?

    Few questions:
    -Is it possible that Phantom goes crazy on GPS mode because of some issue with the GPS signal.
    -How strong the wind needs to be to make Phantom fly like crazy (I didnt fly Phantom at high altitude and it wasnt windy)
     
  2. martcerv

    Joined:
    May 27, 2013
    Messages:
    1,002
    Likes Received:
    2
    GPS signal will change during the flight and just because you have a good signal on takeoff doesnt mean it wont get worse as you get closer to trees or any objects getting in between the phantom and a clear line to a big chunk of sky. It is capturing satellites in all directions and so the closer you get to any object the more likely it will lose some satellites. If it sees less then 6 satellites it will automatically revert to ATTI mode so best to only fly GPS mode in areas that have a clear view to the sky in all directions.

    If your in a place that likely may drop GPS reception I think your better off flying there in ATTI mode as this way you will know what to expect, if its changing between GPS and ATTI mode as signal gets stronger and weaker it will behave fairly unpredictably. If you expect it to be in GPS mode and it reverts to ATTI this can easily catch you out especially in gusty winds where it will go from holding position to drifting in the wind without you realizing why in most cases.

    If your a beginner then best to avoid flying in any areas with big mountains, buildings or trees that may cause GPS reception to be hit and miss. Regarding winds with a strong GPS signal I have flown it in up to about 60kmh speeds and it can hold position quite well, but I am pretty comfortable with ATTI and manual modes and can easily fight any winds if I need to. If your not used to flying ATTI mode and you lose GPS reception even a gentle breeze may catch you out very quickly.

    If you panic and lose control its quite likely you will also move the throttle up or down without noticing altering its altitude when trying to yaw. If you let go of the sticks and it has switched into atti mode the wind will knock it around quite a bit so beware of this and try and maintain a visual of the rear LED so you can tell if its flashing green or yellow.
     
  3. Miika

    Joined:
    Aug 31, 2013
    Messages:
    221
    Likes Received:
    1
    Location:
    Helsinki, Finland
    Thanks martcerv for the good reply!

    Hopefully learning to fly in altitude mode fixes the issue of Phantom Gone Rogue Because Of GPS :). I knew before I bought the Phantom that only way to get good video with it is to learn to fly without the GPS. So now I need to learn how to fly with it. I guess starting carefully flying on low altitudes and in open will help me out.

    Can altitude mode fail? So can the sensors that maintain the altitude fail and make the Phantom go down / crash. Hopefully Phantom doesnt use GPS to figure out the altitude. I'm not sure if its only the AR Drone 2.0 but it has a small camera on the bottom that it uses to maintain the position...
     
  4. martcerv

    Joined:
    May 27, 2013
    Messages:
    1,002
    Likes Received:
    2
    GPS mode is still good to use its just you need to be aware of possible obstructions that could reduce the satellite reception. If your out in the open and have a good gps signal on takeoff this should remain all flight its only when you get closer to other objects that its most likely to drop out. Practicing flying in ATTI will help you out as then if gps lock is lost for some reason you will still be able to maintain control.

    If you lose GPS reception then it wont hold position, RTH may not work and neither will home lock mode. This is the reason you need to try and take good look at your intended flying area to understand possible hazards that can reduce GPS signal. If your only learning and flying just gps mode ifs best to avoid flying in such locations until you are comfortable flying without gps.

    The altidue hold isnt using the gps but other sensors mostly the barometer I would think. If the phantom isnt overweight and setup properly altitude hold is pretty good in both gps and atti modes. Its unlikely to fail but very easy for you to move the left stick off center without realizing. Nothing is fail proof but in over 200 flights mine has never had any issues in ATTI mode.