Hello. I’m struggling to hand-launch an AR-Wing Pro in take-off mode. I’ve failed four times so far, and the nose is starting to get pretty worn out. It always follows the same pattern: after launch, it suddenly rotates to the left and crashes headfirst. Previously, when I flew this aircraft with iNAV 6.0, I was able to take off without any issues. I’m getting flash data, so could you take a look at it?
@ilove04s2k welcome to the community.
Some configuration is incorrect. Post a link to the .bin log file.
Thank you for your reply.
I will share the Bin file of my crash. Here you go.https://drive.google.com/file/d/1oFamtwYKZGByM59ysz1_z7A8edVmVvDT/view?usp=sharing
It’s torque roll. Change TKOFF_THR_MAX to 80% or even less. TKOFF_THR_DELAY to 4sec.
I think it’s natural to turn left with a torque roll, but the aircraft is already heavy (4 cells of 5200mAH Lipo) and the wind doesn’t pass over the wing, so I think there’s a chance that the aircraft won’t lift off if I lower the throttle. Since the aircraft takes off normally with the same iNAV Throttle setting (100%) and Motor Delay (100msec), I think the cause is a delay in elevon control, including torque roll response.
Sorry, but ardupilot would not be able to fly at all if there were a delay of this magnitude in the Elevon control system.
I suspect that you threw the plane too steeply into the sky. When thrown, the pitch (red line) exceeds 75° and then drops to around 45° within the first half-second. Imagine trying to drive your car up a 45° incline and accelerate at the same time. You would find that the acceleration is significantly lower than when driving horizontally.The roll angle was already over 45° and the ground speed is around 4 m/s.
From my experience, throwing at a flatter angle makes more sense, particularly during automatic take-off. This is because acceleration is significantly better and there is a higher probability of exceeding the stall speed earlier.
Rolf
Thank you for your very convincing explanation. I may have angled it too high. I launch from the back so it’s difficult to adjust the angle, but I’ll try not to raise it too high as much as possible.
better focusing on hand launch technique rather than wondering what is wrong with the FC
AR WING don’t have grip on the fuselage so it must swing it for the launch, my successful launch ratio is 10 out of 10 with this technique, and the key is….
as the video title i wrote 
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Slinging it is the way to go. It’s worked well for the wings I have built.
Thanks for the advice. I also have an AR900 and have never had any problems with it. It’s light and has a grip.
I would like to know the meaning of slinging.