No ailerons in auto modes, apart from manual mode

Hi All!

I’m configuring an EasyStar II with an APM 2.5 board and am running into a peculiar problem: in manual mode, all ailerons work fine (Channel 1 en Channel 5). When engaging ANY other mode, the ailerons freeze to neutral and don’t work at all. (stuck at 1503). no matter how much I move the craft around, it’s not doing anything. Rudder and elevator are functioning as planned.

I run the APM through PPM in on pin 1, pin 2&3 are bridged.

I’ve attached two screenshots: manual mode shows channel 1 and 5 correctly, the input equals the output. In the second screen shot (stabilize), the output is set at 1502 and will not move, not through user input nor through moving of the aircraft.

Any help is much appreciated!



Hi Jeroen,

We’re having the same problem with our Pixhawk on a bixler. All control surfaces operate fine in manual mode, but the ailerons (and only the ailerons) stop moving in all other modes. There seems to be no stabilization effect on the roll because of this.

Did you ever find a solution to your problem?


Found the solution and wanted others to know how to fix this problem:

Under the full parameter list, Mission Planner/APM Planner has incorrectly set the reversed servo channels to “0” instead of “-1” as they should have been. Changing those functions from 0 to -1 fixed the problem. In other words, for the ailerons coming out of channel 1 on the Pixhawk that were not functioning properly, changing RC1_REV from 0 to -1 got them working properly in stabilize mode. If I wanted the ailerons to move the opposite direction, I would adjust RC1_REV to 1 instead of -1.