I'm very new to flying and have a flamewheel.  My 16 year old son decided to "play with it" one day last week while I was at work.  When I got home, five of the Graupner 8" x 5" props were toast.  I ordered a set of Gemfan 9443's and installed them today.  With the Graupners, it was very well mannered.  It hovered very nicely and I could control it very well.  With the new props, it will act like it's going to hover when it gets to about 3 or 4 feet off the ground, and then it'll just take off straight up.  It's almost like the props were spooling up when close to the ground and then when they get 3 or 4 feet up, they unwind.  It shoots off like a rocket.  I literally have to move my stick almost to the point of shutting off the motors to get it to begin to descend.  I have the Naza V2 controller and a Spektrum D6i remote.  The motors are MT 2216's.  I have zero experience in setting up this thing.  I have done quite a bit of reading, but can't really find anything about adjusting the gains except for how you want the craft to feel when flying.  Should I need to adjust the gains?  Should I do another calibration of the Naza since it crashed?  Where am I going wrong other than I am completely lost on how to make adjustments?  As i've said before, hovering is out of the question at this point and landing is almost like a lawn dart.  I did adjust the motor idle speed to the lowest setting, hoping that would allow them to spin a little slower, but now, when taking off, they don't spin at all until I'm at 1/2 throttle.  Please don't beat me up very much.  I'm just looking for some help on a very complicated topic!  I appreciate any and all helpful replies!  If I've left out any pertinent info, please let me know!

I'll also add that I noticed the LED is flashing red very fast.  Like the low voltage indicator.   However, the battery is fully charged and I also turned off the voltage protection.  I held it firmly above my head while manipulating the throttle and it still seems very twitchy.  Almost too sensitive.  I'll push just past half stick and the motors start spinning at almost full speed.  Then when I start dropping the throttle, I have to get it almost to the lowest setting before they begin to slow down any.

After a crash is is advised to do a basic and advanced IMU calibration. And after that do a compass calibration at the field you will be flying from.

As far as your props. After a prop change you will need to adjust your gains. That is very important after a prop change.

I'm having issues with a different quad, but I have the Naza-M flight controller. I've been successfully flying Graupner 10x5 carbon fiber props for a couple of years and just experienced the same type problem when upgrading to 12" props.

As far as I can tell the Naza flight controller has default gains set for a particular prop size and weight. Deviating from this requires the gains to be adjusted, however it's not intuitive as to which gains would offset persistent climbing. Intuition would suggest BASIC GAIN > VERTICAL, but that doesn't seem to do it.

I've seen this issue reported here and elsewhere, and respondents either hate on the Naza, blame it on something unrelated like the compass or IMU. If they do hit the dartboard it's usually something vague and less than helpful, as in you have to adjust your gains after changing prop size. I'm not criticizing that answer, but think it would be tremendously helpful if someone could clue us in as to WHAT gains should be changed and in what direction when increasing prop size.

justinlee1 Posted at 2015-6-30 03:52
I'm having issues with a different quad, but I have the Naza-M flight controller. I've been successf ...

Here is our wiki info on gains and gains tuning.
This should help.

http://wiki.dji.com/en/index.php/Gains_Setting