Copter-3.3 beta testing

Warning #1: an issue has been found with Tower's Pause button which can cause the vehicle to fly to an old position if the vehicle has not sent a position update to Tower in some time.

Warning #2: Copter-3.3.2 fixes a bug found in Copter-3.3.1's desired climb rate initialisation which could lead to a sudden momentary drop when switching from Stabilize or Acro to AltHold, Loiter or PosHold.

Warning #3: Copter-3.3.2 fixes an issue found in Copter-3.3.1 which could lead to hard landings in RTL or AUTO if the WPNAV_SPEED_DN was set too high (i.e. >400 or 4m/s) and/or the WPNAV_ACCEL_Z was set too low (i.e. <100 or 1m/s/s).

Warning #4: a bug was found in Copter-3.3 which could cause a sudden crash if you abort a Take-off initiated from a ground station.  Video description is here.  The bug is fixed in Copter-3.3.1 so we recommend upgrading.

Note #1: AC3.3-rc8 corrected a long standing bug in the HDOP reporting.  HDOP values will appear about 40% lower than previously but this does not actually mean the GPS position is better than before.
Note #2: if upgrading from AC3.2.1 the vehicle's accelerometer calibration needs to be done again.
Note #3: set SERIAL2_PROTOCOL to "3" and reboot the board to enable FrSky telemetry like in previous versions.
Note #4: the wiki will be updated over the next few weeks to explain how to use the new features

Copter-3.3.1 is available through the mission planner.  The full list of changes vs AC3.2.1 can be see in the ReleaseNotes and below are the most recent changes since AC3.3.

Sadly this version (and all future versions) will not run on the APM2.x boards due to CPU speed, flash and RAM restrictions.

Changes from 3.3:

1) Bug fix to prevent potential crash if Follow-Me is used after an aborted takeoff

2) compiler upgraded to 4.9.3 (runs slightly faster than 4.7.2 which was used previously)

Changes from 3.3-rc11:

1) EKF recovers from pre-arm "Compass variance" failure if compasses are consistent

Changes from 3.3-rc10:

1) PreArm "Need 3D Fix" message replaced with detailed reason from EKF

Changes from 3.3-rc9
1) EKF improvements:
    a) simpler optical flow takeoff check
2) Bug Fixes/Minor enhancements:
    a) fix INS3_USE parameter eeprom location
    b) fix SToRM32 serial protocol driver to work with recent versions
    c) increase motor pwm->thrust conversion (aka MOT_THST_EXPO) to 0.65 (was 0.50)
    d) Firmware version sent to GCS in AUTOPILOT_VERSION message
3) Safety:
    a) pre-arm check of compass variance if arming in Loiter, PosHold, Guided
    b) always check GPS before arming in Loiter (previously could be disabled if ARMING_CHECK=0)
    c) sanity check locations received from GCS for follow-me, do-set-home, do-set-ROI
    d) fix optical flow failsafe (was not always triggering LAND when optical flow failed)
    e) failsafe RTL vs LAND decision based on hardcoded 5m from home check (previously used WPNAV_RADIUS parameter)

Thanks for your testing!

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    • I think you're referring the the beta release notes.  It's now a stable version, go for it!

  • I have a question about tuning the yaw parameters.  Something I never gave much though to.  Doing a little research (ok, maybe a lot but not getting anywhere) I found vibration being introduced by yaw corrections.  I'm currently have trouble getting my gimbal footage smooth on a 960mm X8 running 3.3 and wondered if this could be the problem and gimbal tuning hasn't improved anything.  The main reason I thought this may be a yaw tuning issue is the mention from others that their units oscillated on takeoff which I have the same issue.  I get a strong pulsing/oscillation on takeoff which goes away once off the landing gear.  What's the best way to check this?

  • I updated from rc-12 beta to 3.3 stable.  At the end of a short flight yesterday I went from PosHold to Loiter and found the stick inputs reversed on pitch and not working on roll.  Switched back to PosHold and sticks were back to normal.  Unnerved me enough that I landed and did not go back up due to wind and congested flight area (trees).

    Will try again later.

    The other strange thing is that when I went to pull the logs there were 46 showing even though I almost always erase after downloading.

    • Developer


      Sticks reversed is almost always caused by accidentally having simple mode or super-simple mode activated.  If you have a dataflash log we can have a look.

      • Why does simple or super-simple mode reverse the sticks?

        I have been using these settings turned on (super simple mode), in case I'm far away and can't see the orientation of the quad, I increase the chance of getting the quad back to me.

        If these modes can reverse controls so easily, perhaps I shouldn't use it! Can you elaborate more on this issue and in what cases it can reverse?

        If it's such an issue, will it be fixed? It sounds very dangerous if it can cause a reverse of controls, especially when the exact reason for this mode is to help prevent you from losing orientation!

        Yes, I know how to fly reversed orientation! Please let's not get into a discussion about learning how to fly.

        Thanks for any advice!

        • Developer

          Hi Rich,

          Super simple or simple mode doesn't reverse the sticks. There isn't a problem with GPS glitches.

          The only way super simple or simple mess people up is when they have it turned on accidentally or when they don't understand how it works and loose orientation.

          These modes have been a part of Arducopter for longer than I have. There is nothing to fix. If a person doesn't like the mode then don't fly in that mode.

          • Leonard, thanks for the reply. This is as I thought also.

            I only wanted to use simple or super simple to help when/if the aircraft is too far away to visually see what is going on.

            As as example, years ago, when I first started learning to fly helicopters, I had a flight where due to strong wind, and not paying enough attention to the distance, the heli got too far away, and I couldn't tell if I was flying back towards myself, or further away. Finally, with the help of a few people, we decided that it was getting larger, and therefore flying back towards myself.

            When I read about super and super simple mode, I thought that it sounded like a perfect way to solve an issue such as this.

            But then people started mentioning doom and gloom! LOL

            I would expect it to get confusing if I flew behind myself, but I never try to do this, it's not natural for me at all.

            I'll test it some more and see. Perhaps I should put it on a switch, right now I have it on a flight mode like altitude hold, but not on all flight modes.

            Thanks again for everyone's input, it certainly give me more to think about.

            • Rich:something that you need to do if you only use simple mode as safe mode is remember that always you have to position your copter in front of you and watching the backward part to you to take off, if not, when you switch to simple in an emergency the copter isn't going to respond as your espectative, the mode works cool if you have that caution, I prefer than super simple, included with compass interferences you can come back your copter, you can remedy with aileron stick in that case, I fly a lot with compass interferences waiting a gps+ext (that just today arrives :D ) and used simple a lot. Yes, experts Rc pilots hate it....but is not my case ;)

              • Yes, thanks for the tips!!

                As an old time RC heli pilot, I always take off with the tail pointed at me, it's an old habit that is hard to kill!

                • As an old time RC heli pilot, I always take off with the tail pointed at me, it's an old habit that is hard to kill!

                  As a not so old time pilot, I do this as well even though I started out on multirotors. I personally LOVE simple mode [no so much super simple]. When I started out it was on multiwii and I didn't even know about things like level [horizon], headfree [simple], or any other assist and it took me probably 2 months just to be able to not break a prop or arm per flight :( Then I leaned about hooking up the FC to the pc and enabling different flight modes and a whole new world opened to me. The pure fun part, not the oh god am I going to crash again part. 

                  My issue flying these things is when they get 50 or so feet out and up they kind of all just turn black to me and I can no longer "see" which way they are pointing. LEDs help a lot but even so when I get 200 or 300 feet then even the LEDS just kind of look white so I lose orientation a LOT. 

                  With simple mode that is not an issue to me as it no longer matters where the MR is facing. My controls are consistent and I can play around more actually flying it instead of worrying about crashing it :)

                  I also have it on a switch but I tend to enable it before take off so I know exactly which way my controls are at all times. I don't use it all the time but when I do I really am glad it is there.

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