Version 2.5 of the ArduCopter code is now available in the AP Mission Planner and in the downloads area!



  1. The first ArduCopter code release optimized for the APM 2.  Leans and drift should be much reduced or even eliminated for most users.  This was accomplished through a number of core improvements to the DCM implementation by Tridge like this one and this one.
  2. Loiter and waypoint following should be improved due to a D term bug fix, some tuning and the improved DCM performance mentioned above.
  3. On start-up, the yaw heading is updated with first successful mag read (so you should no longer see the slow rotation from north to your actual heading).
  4. Increased output rate to ESCs to 490hz.  This update rate is also user selectable using the new RC_SPEED parameter.
  5. hexa copter stability patch bug fix (should resolve slight flattening when pitching forward and accelerating very rapidly).
  6. improved baro filtering
  7. fix to dataflash logging of Mag heading
  8. addition of H1 swash plate type and bug fix for proactive yaw compensation for collective pitch changes for TradHelis.



The default PIDs are optimized for a 3DR/Jdrones quad with 850 motors and 10" props. If you're using more powerful motors/props, start by turning down Rate Roll P in 25% steps.

While some testers have reported very good flights with the default PIDs, some have reported that this release is a little "sharper" due to the DCM improvements and have found they needed to:

     reduce stabilize P by 10% (i.e. 4.5 -> 4.2)

     reduce stabilize D by 30% (i.e. 0.15 -> 0.10)

     increase rate D from 0 to 0.001

Tuning loiter can be tricky.  Refer to the discussions which will appear below for more community feedback on what parameters work best.


Please post your feedback in this discussion.  For enhancement requests  and bug report, please add them to the arducopter issues list.  When possible please include logs (tlog and/or dataflash) and tell us whether you're using APM1 or APM2 and what version of the software you're using (presumably 2.5 but tell us anyway!).


Thanks for this release go to the developers (both in the core team but also those who have provided bug fixes through the issues list) and also the community members who participated in the previous release thread and provided some great detailed information in the form of issue reports and logs which allowed us to nail some bugs!


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In 2.4.1... In Stab.. I could lean forward a lot.. like 30-40 deg.. and all the motors would speed up and the copter would accelerate  across the field with any change in altitude.

2.5.. this fantastic feature is gone… or there some parm I need to change.. ?

Eddie Weeks

@Gerrit: you must reduce Stab and Rate parameters with 2.5, especially STAB_D and RATE_P.
RATE_D 0.009 i think is too high, i use 0.008 in my heavy X8 and 0.003 in my little xquad.
Im my X8 "STAB_D is 0" due diagonal wobbling just if i put this parameter to 0.002.

Marco what setting are you using on your X8 quad? Before on my X8 I had Stab Pitch/Roll at P 3.800 I 0.001 IMAX 40 . Will this be OK with 2.5 do you think?  Also what about D? Ive no idea what that does because not used it in 2.4.1.

Also how have you got your motor speeds now setup with the independent channels for each?

also did you test fail safe and RTL and how did they go?

(To Boris Rabusic) : Same problem here...No more communications, dead hexa, so trying to download arduino...However v2.41 was not working fine with my foldable hexa x, so not sure if it is worth it to go back to 2.3 ... Are 1280 boards doomed ?  :(

Short video of what my Y6 has been doing with v2.5.  I have tweaked and tuned till I am stumped.  Flew good in stabilize with 2.4.1.  In the video the wobbling is almost non stop.  It is also yawing bad on its own.  Using APM1/2560.  I know that it is not a hardware problem.  If I reload earlier stable firmware versions it flies great.

Devs, Thank you so much for all your work! You are truly a great team!

I have a  question and please forgive me if this has been addressed somewhere else. Is the camera pitch and roll on the APM2 working on this release? or should i wait for a future release?

Have a great day flying!


update... Set Thro Trim to 530.. then the alt hold worked again.....

Tuned Loiter but unable to stay in a 100x200 field... out of options..

Thanks Marco,

I re-tuned the quad to the guide in this post and set the value of STAB_D to 0.000. This is better now. (btw wouldn't it be a good idea to post this method on the wiki?) 

I still have a yaw issue, sometimes the quad will yaw about 45-90 deg to the right (CCW) when power is increased. this can happen on throttle input, but also when alt-hold is engaged and the quad is compensating.

But wind has increased to 5 Bft so I'll have to stop flying. I think i'll compare 2.4.1 to this setting of 2.5.0 on a less windy day.

I have attached my current settings. 


  Is the camera pitch and roll on the APM2 working on this release?

Seemed to work on my x-quad. I have issue of Gimball servos affecting the voltage of the board - especially connecting to MP is an issue. Disconnecting the servoleads to the servos makes the issue dissapear.

Many thanks on my behalf to the developers! :-)

Heikki, i had the same problem,solved it by mounting a 5 amp ubec

well, if someone can remove non essential part of code (for example waypoints etc), it would fit.

I've tried to disable logging, but still it misses small amount of memory..

I need help please.

I flew today with my octo and the new firmware v.2.5. I found a problem that I can not disarm the motors after the AUTO TRIM mode. It continue to run despite the throttle is at 0I have to cut the battery to stop the motors.


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