AR Wing pro with Ardupilot and Matek f765 Auto takeoff failure

The first flight was a crash I think there is a problem with auto takeoff, TKOFF_LVL_PITCH=15 but the plane went down, what am I doing wrong, please help…


Anyone for help???

Please share your flight log.

Did you fly your vehicle in manual mode?
Did it fly well in it?
Please share your .bin file from your SD card for a detailed look. (786.8 KB) I didn’t fly it in manual mode yet, because I can’t throw and steer at the same time, that’s why the autolaunch feature is so important to work. Hopefully you can point me in the right direction.

As a rule my maiden flight is ALWAYS in manual mode.
Always check your CG. I built this arplane, it’s pretty slick but the CG is a PITA.
I had to add a 5oz lead ballast by filling the nose of the aircraft behind my runcam nano.
I insulated the lead ballast with electrical tape in stuck in the gap in the middle of the nose and secured it in place. When the 3300ma 4S battery is installed I can balance it with my fingers on the cg points perfectly. That was the first test. The second test is to be SURE ARDUPILOT has RCMAP_ROLL and RCMAP_PITCH set correctly. ALSO check SERVO1_FUNCTION, SERVO2_FUNCTION, and SERVO3_FUNCTION. Be sure left elevon, right elevon, and throttle are set correctly. It’s entirely possible that you have the SERVO Functions rand the rmap settings reversed. If it’s reversed you can have proper control surface movements by r/c but incorrect from the autopilot. I know first hand because when I was a newbie I did it. But my preflight checklist included checking r/c action with the control surfaces, r/c range test, roll plane to left, right, up, and down while checking the control surface movement.

Here’s what you need to test:
Input - Action
Roll right - Left elevon goes up and right elevon goes down
Roll left - Right elevon goes up and left elevon goes down
Pitch down - Both elevons go up
Pitch up - Both elevons go down
If your movements are incorrect then you need to adjust which servo output is left/right and the reversals of each elevon.

From the video it appears that either your CG is tail heavy, Ardupilot servo config is wrong, combination of both …

So the easiest thing to do is double check your CG
Next: Double check your ardupilot config, specifically SERVO functions and RC Map.

Hopefully this helps and you will be in the air in no time.

Hi Jerry, thanks for the reply. As a matter of fact afterwards it seems that I did do everything right, except for the TKOFF_LVL_PITCH value that was advised by Painless 360 to 15 degrees which is not enough, I only changed this to 30 degrees, and TKOFF_THR_MAX,95 I set to 100 last week and I had my very successful maiden and second flight with auto takeoff and RTL, FBWA and CRUISE worked like a dream.
I already added 82 Grams of lead before in the nose which was spot on.
Now hoping for better weather so I can fly some more!

Awesome! I have been too chicken to to try Auto Takeoff! LOL… You gave me some useful information.
Here’s my maiden and my 2nd flight. I’m still keeping the flights short because I am still tuning parameters. For the first launch a friend tossed the wing sidearm like a frisbee. Second launch a friend (also my club’s safety officer) did an overhead launch. Hopefully next week I’ll test CRUISE, RTL, and Waypoints.


2nd flight with throws reduced to 80%, 20% EXPO on the Elevons

Do you have some video of your successful flight ?

Hi Jerry, Cool video and a beautiful location also. Nice to see everything is working as expected for you.
I have a video, but the quality is poor, I already ordered a new VTX and antenna from TBS, hopefully I get better range than.

I now have to manually switch the power level on the VTX, but what I don’t understand is that the range seems to get worse while I switch from 200mw to 1000mw, you’d expect it to get better not worse.
We’ll I guess I still have a lot to learn about antenna’s transmitters etc.

Hopefully the wetter gets better soon so we can have some fun!

That’s an awesome flight! Very stable.
It looks like you have a nice location to fly as well.

I am going to attempt to take my arwing out further along the river inlet. The r900 telemetry range is not optimal. It drops out often even with the flight pattern of my 1st flight. I am forced to just time my flight and turn audio telemetry alerts off.

Well I hope you have nice weather for your next flight.

I had similar issues switching vtx power. Make sure the antenna polarization is the same on your aircraft and receiver. Also sometimes at high power and low altitude you end up receiving reflections. The reflections mess up the video. I use RHCP antennas on my aircraft and goggles… and 200mw at the field where I fly. The video I posted was from the locally recorded video from the aircraft.

  1. Do you use Jumper R900 receiver? Which range do you get with it?
  2. Which transmitter do you use?

Telemetry range is horrible and not very useable. I am going to switch my AR pro to a standard mavlink telemetry config.
I am more than likely going to dump R9 and switch to tbs crossfire.

The internal 2.4ghz pcb antenna is also sub par. I bought my Jumper T-18 to consolidate my FrSky, spectrum, and R9 equipped models to one transmitter. I can’t. My original ACCT FrSky QX7 has 4x the range of my T-18. My spectrum dx 8e has 3 times the range of the T-18.

Also because R9 telemetry range is limited I have to fly old school and limit flights by time. I wanted to have realtime bearing, elevation, speed, pitch, roll, amperage, and flight battery voltage… but jumper dropped the ball. At the moment I still need to bring 3 radios to my club’s airfield.

Range depends on location.

I wouldn’t fly farther than 2.2km with R9, 1.2km with good old FrSky ACCT, and 900m with Spectrum DSMX

I use a R900 reciver with a jumper T-18
2.2km max so far…rssi -75db I won’t fly.farther than that

Thank you for your fast response! I’m a bit confused as for the exact receiver you are talking about. You’ve mentioned at least two in your posts: R900 and R9 - are they Jumper R900 and FrSky R9? Do you use both of them or was is a typo?

Yes I use the FrSky and the jumper r900 receiver with my T-18. Tx range is ok but telemetry cuts out early. Only useable when close, like on the ground.