ArduCopter 2.5 released!

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!


You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –


  • Developer

    Thanks to the whole team and to all users who knew how to wait!
    Ehm... why the thread is under the section "ArduPlane"? :P

  • Congratulations dev team, this release looks really great.

    On the other hand last reports on Y6 where not that good.

    Has Anyone flown a Y6 with 2.5 successfully??  I'm worried about last messages reporting a turning behaviour on take off... unflyable...


  • Randy.

     Can, the rc_speed to 500hz?

  • Awesome! Thanks guys!!

  • ready and loaded in the morning quad large field test apm 1, 10x4.5, lv EZ4, frame and engine 650v2 XAircraft, 10amp esc, 1350 kg, 900xbee, bat 2650,
    thank you all.

  • Moderator

    hmmnn...something I've just noticed after another quick flight, when I switch to ALT_HOLD (was done at 2m high) the quad drops like a stone! On the ground and still in ALT_HOLD it won't take off until the throttle stick is almost at full? Normal hover for me is about 55% stick travel.

  • Fantastic!!! Thanks for all the hard work guys. Now though I'm wondering should I wait for a week or so and see what the general feed back is, and stick with the natural 2.4.1 ?? Or just load and try..hmmm.. thinking thinking ..

  • Moderator

    Thank you to all involved, great job! We had to wait a while but it's now here.

    Just had a test flight in the garden with the official v2.5 on APM2 (although I did fly 40 minutes yesterday with a recent git version) and all is good, I did not have a leaning incident which has been something that has been plaguing my quad. It's a X525 frame with KDA20-20L motors, HK SS 25A ESC's, 3 or 5 Ah 3S batteries, 11x4.7 APC SF props, weight 1.3kg. Default params.

    Looking forward to more trouble-free flights

  • Wow...!

    I'm ready to go now.....I've be waiting on this very cool update to put my new

    hexa up for the first time with it's new reasoning abilities !!!

    After watching the vid ... I am glad I waited .


    Yipee !!!


    Thanks so much to All for getting IT done !!!





  • I can't wait to try this! Awesome job everyone :)

This reply was deleted.


DIY Robocars via Twitter
RT @a1k0n: I'm gonna try to do proper offline reinforcement learning for @diyrobocars and throw away all my manual parameter tuning for the…
21 hours ago
DIY Robocars via Twitter
RT @circuitlaunch: DIY Robocars & Brazilian BBQ - Sat 10/1. Our track combines hairpin curves with an intersection for max danger. Take tha…
DIY Robocars via Twitter
RT @SmallpixelCar: Had an great test today on @RAMS_RC_Club track. However the car starts to drift at 40mph. Some experts recommended to ch…
Sep 11
DIY Robocars via Twitter
RT @gclue_akira: 世界最速 チームtamiyaのaiカー
Sep 10
DIY Robocars via Twitter
RT @DanielChiaJH: Always a good time working on my @diyrobocars car at @circuitlaunch. Still got some work to do if I’m to beat @a1k0n howe…
Sep 10
DIY Robocars via Twitter
RT @SmallpixelCar: My new speed profile for @RAMS_RC_Club track
Sep 10
DIY Robocars via Twitter
RT @SmallpixelCar: Practiced at @RAMS_RC_Club today with my new @ARRMARC car
Aug 28
DIY Robocars via Twitter
Aug 24
DIY Robocars via Twitter
RT @gclue_akira: 柏の葉で走行させてるjetracerの中身 #instantNeRF #jetracer
Jul 4
DIY Robocars via Twitter
Cool web-based self-driving simulator. Click save when the AI does the right thing
Jul 4
DIY Robocars via Twitter
RT @donkey_car: Human-scale Donkey Car! Hope this makes it to a @diyrobocars race
Jun 25
DIY Robocars via Twitter
Jun 25
DIY Robocars via Twitter
Jun 16
DIY Robocars via Twitter
RT @GrantEMoe: I won my first @diyrobocars @donkey_car virtual race! Many thanks to @chr1sa @EllerbachMaxime @tawnkramer and everyone who m…
Jun 13
DIY Robocars via Twitter
RT @gclue_akira: JetRacerで自動走行したコースを、InstantNeRFで再構築。データセットは別々に収集 #jetracer #instantNeRT
Jun 13
DIY Robocars via Twitter
RT @SmallpixelCar: SPC 3.0 Now the motor also works. This car is doable. I just need to design a deck to mount my compute and sensors. http…
Jun 13