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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small info.

I tried to upgrade from 2.4x to 2.5 using MP, board is 1280 and after eeprom 116->117 message there was message about being unable to update. Board can not boot, or connect over MP again.

I'll try to upgrade it over arduino.

I've restored it to 2.4.1 using Arduino with logs disabled.

2.5 can not fit on 1280 :(

First, let me congratulate the development team with their efforts. It's great to see arducopter moving on. 

I just had time to fly 2.5, uploaded from APM 1.1.53, but unfortunately in my case it doesn't perform as well as 2.4.1. I had a better flying experience with 2.4.1. I'm flying APM 1.4 on a stock GAUI 330x frame. I first tried to fly with the default parameters but just as in case of  2.4.1 the defaults are very smooth when flying indoor or with no wind but just not responsive enough to be controllable in windy conditions. 

In my case version 2.4.1 was rock stable and very controllable with 'ninja' parameters RATE_*_D 0,009, RATE_*_I 0,1, RATE_*_P 0.189 an d STAB_*_P 12. I could easy fly  this in very windy contions. Alt-hold was fine but I never managed to get any decent loiter. (see attached parameter files)

I had to reduce these to 0.007, 0,070 and 0,15 in 2.5.0 to tame the quad, but it is still more twitchy and not quite as well controllable. However I must say there was a lot of wind (~4 Bft.). 

Is it maybe true that the improvements are only for APM 2.0 hardware?


Wait?! I thought you'd seen my video - there was no chance of that performance with 2.4.1!

Go on, go on, go on!

I had the quick drop on first attempt, i think because i went straight in alt-hold mode. After a quick hover all was fine.

I only have an APM 1 and its made a huge difference for me. I've had to back off on the settings slightly but Ive ended up with even more locked-in precise flying -- oh until this morning when i accidently set my home position under a tree whilst sheltering from the rain - then couldn't get my hands back in the TX protector quick enough... one broken arm on my DJI frame...- think i got it on video though ;)

Loiter is very stable and smooth...on the air about 40 meters.

congratulation develop team....

thank you 


Gerrit, I think this is just a case that you will need to retune your parameters.  The performance of your quad should only be better with this release.

A big thanks to the Dev team, the hard work is appreciated!

Just uploaded v2.5 using MP and checking config and I noticed something which may cause confusion or problems.

When using Ch6 Opt for "In Flight Tuning", the instructions in the Wiki seem to differ from the experience in MP (v 1.1.53).

To achieve the upper and lower values for Rate P (for example) between 0.065 and 0.145, the wiki example implies values of 65 and 145 should be entered, i.e. a multiplier of 1000 should be applied. However if entered, they result in considerably higher figures appearing for the low and high limits. The result is an abnormal Rate P value, which may cause issues (i suspect).

The link to the Wiki page is:

The text is located here "In Flight Tuning" -> "Method 1" -> Third Paragraph.

Just a note to everyone, actually an addendum to the initial thread posting because I think a significant aspect of this release was missed.

Major credit to Tridge again on this one, because not only is the DCM better, more accurate and more stable, it's actually FASTER!  Whereas previously we were struggling to achieve the desired (correct me if I've got the numbers wrong) 200hz rate on the code, it is now running well over that, and in fact can push close 300hz.  This is a significant improvement, and will again allow us to add more features in the future without the CPU getting bogged down.

So once again, (as with the parameter changes) Tridge has managed to both fix a problem AND improve performance.  Truly remarkable.

You're correct, MP has changed, I'll change the wiki.

Yes... Some thing happen to me... Broke all kinds of stuff...  AMP2.....2.5...

stock param execpt Stab_P Stab_Yaw...

On large Tri-Copter

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