ArduCopter 3.2.1-rc2 (release candidate #2) has completed beta testing and has been released as the official version available through the mission planner and other ground stations.

Changes from AC3.2 are listed below and in the ReleaseNotes:
1) Enhancements:
    a) reduced twitch when passing Spline waypoints
    b) Faster disarm after landing in Auto, Land, RTL
    c) Pixhawk LED turns green before arming only after GPS HDOP falls below 2.3 (only in flight modes requiring GPS)
2) Safety Features:
    a) Add desired descent rate check to reduce chance of false-positive on landing check
    b) improved MPU6k health monitoring and re-configuration in case of in-flight failure
    c) Rally point distance check reduced to 300m (reduces chance of RTL to far away forgotten Rally point)
    d) auto-disarm if vehicle is landed for 15seconds even in Auto, Guided, RTL, Circle
    e) fence breach while vehicle is landed causes vehicle to disarm (previously did RTL)
3) Bug Fixes:
    a) Check flight mode even when arming from GCS (previously it was possible to arm in RTL mode if arming was initiated from GCS)
    b) Send vehicle target destination in RTL, Guided (allows GCS to show where vehicle is flying to in these modes)
    c) PosHold wind compensation fix
    d) prevent infinite loop with do-jump commands pointing at each other
    e) pixhawk memory corruption fix when connecting via USB
    f) vehicle stops at fence's alt limit in Loiter, AltHold, PosHold (as it did in AC3.1.5)
    g) protect against multiple arming messages from GCS causing gyro calibratoin failure

Thanks to Raph for the video.  This is actually a video from AC3.2 until we have one specific to AC3.2.1.

Views: 57475

Reply to This

Replies to This Discussion

No need to re-move and re-install.  You can press CTRL-F and select refresh parameters and that will download an XML file from github with all of the parameters listed.


I've been told that sonar altitude hold is not present on APM 2.0, due to code space, is it right? In this case, what should I do to have it back?

Thanks a lot,


Sonar seems still enabled

BTW, this is where you can enable/disable features and then compile the code yourself.

I had crashed yesterday, it was my first flight with 3.2.1rc2.   I don't know if it is related to the version or just a coincidental issue.

I live where it is difficult to get good GPS due to high tension power lines running very near my back yard.  So the first part of the log is  sitting idle on the ground waiting for more satellites.  

I got tired of waiting when I got to 7 sats, and HDOP 2.1  

I decided to just take off and see how stabilize and alt hold were looking.

I armed and took off and it handled extremely well, Stabilize was effortless, taking off and landing was great, could'nt even feel ground effect.   

I hovered around in my small fenced in back yard for a minute or two in alt hold.  Suddenly, the copter rolled 90 deg, went to full throttle went for about 30 feet a foot off the ground  and crashed into the wooden fence at a high speed.  It did quite a bit of damage and my NEX5r departed, broke out a whole in the fence and the camera tumbled 50 feet or so into my neighbors yard!

I don't know what could cause a full throttle state, but it was scary. this is a 6s 750 size quad with 15.5 inch CF props, and large pancake motors... It is a real monster when it is out of control at WOT. 

I have attached the tlog and the flash log in case someone could look at it to see if they can spot the problem.  I have a lot of rebuilding to do, and I hope to find out where my problem is before I re-embed to problem in the repaired copter. All the action is in the last two minutes..  you will see that the only two flight modes I was in were Stab and Alt-hold.  At the end there were some GPS and Compass health issues, but I think that was when the copter came apart and was stuck in the fence..  the compass/gps was hang in from the wires  :-(


What a pitty. Some time ago, with another vers I had similar issue, but using the gps, i put a cheap camera near the gps, it lost signal and when I change to loiter the copter rolled 45 deg and flies a full trottle, I inmediatly change to stab and luky no consecuences but if you don't use gps modes it couldn't be the problem and the gps and compass gitch ocurrs before the problem, thats normal when you crash, perhaps a hardware fail? motors, props, esc, etc. all working well? interesting to know the real issue. 

My most "unpredictable and unexplainable" flight events have  been near powerlines and wire routers. They were all in "assisted" flight modes.

I am no longer attempted to fly assisted modes in "noise saturated" urban environments. Good speed with your repairs.

Discovered the Cause!

Thanks guys for the feedback,, I think I have found the problem.

I mentioned in my earlier post that the force of hitting the fence caused my camera to propel through the hole in the fence into my neighbors yard..

Indeed, there was no sight of the camera and it's heavy duty gimbal, (1.5 lb's total weight) and there was a large hole in the fence, and it looked like there was something in the hedge at the other side of the yard that I thought had to be the camera..

After getting a chance to talk to the neighbor, and searching for it, it didn't turn up in his yard, what I saw turned out to a water sprinkler, not the camera..

So back to my back yard, looked around and bingo!  the camera and gimbal were on the ground exactly below where the trouble began!   (I do have some tall weeds that was hiding it)

This means the camera/gimbal fell off the frame causing the CG to shift radically and what initiated the flyaway, and was not caused by it.

The camera was mounted a rides on a rail.  That railsystem supports the camera/gimbal , in the front part of the copter, and the 6S-4500 MAH battery pack was on the rear rail to counter weight the Camera/Gimbal.

 This would have made the copter very tail heavy suddenly when the camera\gimbal fell off.. 

Examining the wreckage revealed that the gimbal was mounted on a plate that was mounted to the rail system and the screw heads had pulled though the holes, I should have put some washers. there.  I didn't realize that the pound and a half of weight could stress the plate to the extent that it did.

At least I can repair it and have confidence that I know what happened and don't have to worry about a undiagnosed problem lurking to surprise me again.

FYI, I am surprised that I didn't see the camera go.. A lot of stuff happened in just a second or two. I might have glanced at my ground station for an instant or something.

This also strengthens my awareness of what can go wrong, and the danger that is present with large copters


Good news Richard, It's great when you know what had happen to enjoy next flyes; thank's for share your bad experience I learn more from others experiences.;) 

What gps do you use?

Hi Richard

It is the 3DR GPS/Compass

I know this isn't as precise as I would like, but it is the one shopped with the 3DR PIXhawk, the combo mag GPS, I don't know the manufacture and model (of the actual sensor) . It comes in a nice plastic case and mounts on a mast.


I know this is pricey but I had much better luck with this  I think I had a few bad flight from poor gps count and I know for sure I had a couple because of slightly damaged wires to the 3dr gps.

ps the build quality was really good. Better than others on eBay. 

Reply to Discussion


© 2020   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service