ArduCopter-3.0.1 released!

ArduCopter 3.0.1 has been released and is now available in the Mission Planner,, GitHub and the new Downloads Area.

Warning #1: Compass calibration and reducing interference is far more important than with 2.9.1b

Warning #2: GPS glitches can cause sudden and aggressive position changes while in loiter mode.  You may wish to reduce the Loiter PID P to 0.5 (from 1.0) to reduce aggressiveness (see image below of where this gain can be found in mission planner).

Warning #3: optical flow is not supported but will be back in the next release (AC-3.0.2 or AC-3.1.0).

Warning #4: loiter turns does not maintain altitude.  This bug will be fixed in AC-3.0.2.

Warning #5: This release has only been lightly tested on Traditional Helicopters.

Improvements over 2.9.1b include:

  • Inertial Navigation for Loiter and Auto meaning much more accurate control (Randy,Leonard,JonathanC)
  • 3D navigation controller follows straight lines in all dimensions between waypoints (Leonard,Randy)

         WPNAV_SPEED, WPNAV_SPEED_UP, WPNAV_SPEED_DN, WPNAV_ACCEL allows configuring speeds and acceleration during missions

  • "compassmot" to compensate for interference on compass from the pdb, motors, ESCs and battery.  (Randy,JonathanC) (Set-up video here)
  • Safety improvements:
    • simple Tin Can shaped Geo Fence
    • pre-arm checks to ensure all calibration has been performed before arming (can be disabled by setting ARMING_CHECK to zero).  (video description here)
    • GPS failsafe - switches to LAND if GPS is lost for 5 seconds
    • stability patch improvements to stop rapid climbs in very overpowered or overtuned copters
  • Circle mode improvements including "panorama" when CIRCLE_RADIUS set to zero (Randy,Leonard)
  • SONAR_GAIN parameter added to allow better tuning of sonar surface tracking
  • CH8 auxiliary switch (same features as CH7)
  • works on PX4 (some minor features still not available) (Tridge,PatH)

How to upgrade:

1. Make sure you are using Mission Planner 1.2.59 or newer (get it here)

2. Click on the MissionPlanner's Hardware, Install Firmware screen.  The version numbers should appear as "ArduCopter-3.0.1", then click the appropriate frame icon and it should upgrade as per usual.

3. Reduce the Loiter and Alt Hold PIDs if you have modified them from the defaults.  The modified PID values for the 3DR frame can be seen in the image below.

Note: Nav parameters have been combined with Loiter so do not be concerned if you can't find them.


4. Although not directly related to this release, if you purchased an APM prior to March of 2013, update your PPM encoder to the latest firmware (instructions here).

5. Try out the new version in stabilize mode first, then alt-hold, then loiter and finally RTL and Auto.

Numerous How-To videos are available:

Special Thanks to MarcoDaveC and the large number of testers on the pre-release thread who put their copters at risk during the extended testing period.  Some of their videos can be found hereherehereherehere and here.  Thanks also to MichaelO for the MP changes required for this release.

All feedback welcome.  Please put your questions, comments (good and bad!) below.

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  • First of all I am amazed with all of this and thankful to boot!  The Developers are fantastic.

    Randy, et al,

    I have a slight issue with RC5 that wasn’t present in prior versions. I have an APM 2.5 with External Compass(raised 10cm) mounted on a X560 quad, 3DR 850kv, simoneK ESCS.  It flies well on current release except for TB in loiter and occasional left roll “twitching”.  With RC5 I get roll and pitch spikes when the APM is stationary and disarmed.  What is really strange is the craziness that happens when I plug in the fight battery to the power module.  The HUD starts spinning around and the pitch and roll data points(mainly roll) are all over the place.  As soon as I remove the battery, she levels out and the occasional pitch/roll spikes return.

    I attempted to do accel calibration with and without the battery installed.  With battery the cal fails, without, it’s successful.  However, the craziness returns every time I plug in the battery.  I’m afraid to go any further with RC5 at the moment. I’ll revert back to the release version. Oh, this craziness occurs when MP is connected by 3DR radio or USB.

    I have included an tlog if anyone would be so kind to take a look.

    Battery plugged in at 13%
    Calibration attempt w/batt 19.7% (Failed)
    Removed battery at 20.4%
    Calibration attempt WO /batt at 22.5% (Successful)
    Battery plugged in at 24.9%

    Thanks all!


    2013-10-23 22-53-34.tlog
  • Moderator

    Randy, would it be possible to get this issue included in rc5 and/or the final release?

  • Hah wow! Before leaving for work, I flashed 3.1-rc5 on my discovery quad and took it out to fly during lunch. Amazing, like I have a new quad in my hands! This is in combination with my new external compass, which also makes all the difference.

    I set it up to do AutoTune which worked flawlessly first time. Took off, hovered a little in ALTH mode and flicked the Ch8 switch which engaged the AutoTune samba :D I could retrieve the quad when it wandered too far off inbetween, it resumed tuning everytime. It started doing sideways roll movements and proceeded with pitch tuning.

    DEV TIP: One thing that could be implemented as a usability feature is *something* that the quad could do to indicate that AutoTuning has finished. I assumed it was as soon as it hung still for a few moments after which I landed and disarmed it.

    All in all: this firmware version is a massive improvement, hats off to the devs!

  • Hi Randy,

    Can you please help me understand what is happening with INS_GYROFFS_X, INS_GYROFFS_Y and INS_GYROFFS_Z on each boot and duringa accel. calibration?

    Seems like these values change randomly each time i fly and they are affecting my artificial horizon as well as flight. I don't usually boot the copter on level ground (grassy area, never level) and these values seem to change every time and (I believe) affect my "level flight".

    If so, what is the purpose od accel. calibration and how to make them stop from changing, or at least have them be accuratly calculated every time.


    Thank you,


  • Here is 3.1 rc4 autotuned in all its glory :)

    Only thing new I am going to do from this is add the external compass.

  • Is there a way to fly in ACRO  mode with 60 deg pitch/roll limit removed?   I would like to be able to do flips by pulling on the sticks.  I am aware of the FLIP flight mode (toggle) which just does automatic flip.

    Are we getting 3.1 Halloween 2013 release?

  • Finally, I had a windless evening.. 3.1rc5 tunes perfectly in 5 minutes. The new folks just getting in are so fortunate.. Manual tuning is now a thing of the past. The auto-tune PIDS are flying so much better than I ever attained over the last year tuning manually..  Thanks Dev team for all your efforts..


  • Is there a reason why I cannot reverse radio channels using the RC6_REV, RC7_REV, etc. ???

    It works fine for RC1_REV up to RC4_REV but any channel higher has no effect.

  • RC5, great! 

    Just a quick check:

    I just saw that COMPASS_EXTERNAL is set to zero in this release. I have it earlier enabled and calibrated as well, as external one. Works great, just tell me please is this ok to remain as zero value, or I have to activate it with 1.

    Thanks again for Your efforts! 

    ps With this progression of developnent, I can bet  for at least 1 more breakthrough event till the New Year, glow motors and apm/pixhawk/else :)

  • Hi Guys. I'm hoping someone here can help me out. I just had a crash today using arducopter 3.0.1. I was flying in loiter, then when I switched to stabilise all motors stopped and the quad crashed. I can see from the logs that my throttle input was about 50% however throttle out decreased to almost zero when I switched to stabilise mode.

    Logs and more info is available here: .

    Here is throttle in and out. Any help will be greatly appreciated:)!

    Have a great day:)!


This reply was deleted.


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